* [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
@ 2022-09-08 15:04 ` Jisheng Zhang
0 siblings, 0 replies; 10+ messages in thread
From: Jisheng Zhang @ 2022-09-08 15:04 UTC (permalink / raw)
To: Paul Walmsley, Palmer Dabbelt, Albert Ou, Guo Ren
Cc: linux-riscv, linux-kernel
Testing tools/testing/selftests/timens/vfork_exec.c got below
kernel log:
[ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
[ 6.842255] Oops [#1]
[ 6.842871] Modules linked in:
[ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
[ 6.845861] Hardware name: riscv-virtio,qemu (DT)
[ 6.848009] epc : vdso_join_timens+0xd2/0x110
[ 6.850097] ra : vdso_join_timens+0xd2/0x110
[ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
[ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
[ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
[ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
[ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
[ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
[ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
[ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
[ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
[ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
[ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
[ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
[ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
[ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
[ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
[ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
[ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
[ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
[ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
[ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
[ 6.877484] ---[ end trace 0000000000000000 ]---
This is because the mm->context.vdso_info is NULL in vfork case. From
another side, mm->context.vdso_info either points to vdso info
for RV64 or vdso info for compat, there's no need to bloat riscv's
mm_context_t, we can handle the difference when setup the additional
page for vdso.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
---
since v1:
- add "Fixes" tag
- fix build error when CONFIG_COMPAT is enabled.
arch/riscv/include/asm/mmu.h | 1 -
arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
2 files changed, 95 insertions(+), 84 deletions(-)
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
index cedcf8ea3c76..0099dc116168 100644
--- a/arch/riscv/include/asm/mmu.h
+++ b/arch/riscv/include/asm/mmu.h
@@ -16,7 +16,6 @@ typedef struct {
atomic_long_t id;
#endif
void *vdso;
- void *vdso_info;
#ifdef CONFIG_SMP
/* A local icache flush is needed before user execution can resume. */
cpumask_t icache_stale_mask;
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 69b05b6c181b..8ca3b821e1b5 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
extern char compat_vdso_start[], compat_vdso_end[];
#endif
+enum vdso_abi {
+ VDSO_ABI_RV64,
+ VDSO_ABI_RV32,
+};
+
enum vvar_pages {
VVAR_DATA_PAGE_OFFSET,
VVAR_TIMENS_PAGE_OFFSET,
@@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
return 0;
}
-static void __init __vdso_init(struct __vdso_info *vdso_info)
-{
- unsigned int i;
- struct page **vdso_pagelist;
- unsigned long pfn;
-
- if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
- panic("vDSO is not a valid ELF object!\n");
-
- vdso_info->vdso_pages = (
- vdso_info->vdso_code_end -
- vdso_info->vdso_code_start) >>
- PAGE_SHIFT;
-
- vdso_pagelist = kcalloc(vdso_info->vdso_pages,
- sizeof(struct page *),
- GFP_KERNEL);
- if (vdso_pagelist == NULL)
- panic("vDSO kcalloc failed!\n");
-
- /* Grab the vDSO code pages. */
- pfn = sym_to_pfn(vdso_info->vdso_code_start);
-
- for (i = 0; i < vdso_info->vdso_pages; i++)
- vdso_pagelist[i] = pfn_to_page(pfn + i);
-
- vdso_info->cm->pages = vdso_pagelist;
-}
-
#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)(vvar_page);
-}
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a task
- * changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- struct vm_area_struct *vma;
- struct __vdso_info *vdso_info = mm->context.vdso_info;
-
- mmap_read_lock(mm);
-
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
- unsigned long size = vma->vm_end - vma->vm_start;
-
- if (vma_is_special_mapping(vma, vdso_info->dm))
- zap_page_range(vma, vma->vm_start, size);
- }
-
- mmap_read_unlock(mm);
- return 0;
-}
-
static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
{
if (likely(vma->vm_mm == current->mm))
@@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
},
};
-static struct __vdso_info vdso_info __ro_after_init = {
- .name = "vdso",
- .vdso_code_start = vdso_start,
- .vdso_code_end = vdso_end,
- .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
- .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
-};
#ifdef CONFIG_COMPAT
static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
@@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
.mremap = vdso_mremap,
},
};
+#endif
-static struct __vdso_info compat_vdso_info __ro_after_init = {
- .name = "compat_vdso",
- .vdso_code_start = compat_vdso_start,
- .vdso_code_end = compat_vdso_end,
- .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
- .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
+static struct __vdso_info vdso_info[] __ro_after_init = {
+ [VDSO_ABI_RV64] = {
+ .name = "vdso",
+ .vdso_code_start = vdso_start,
+ .vdso_code_end = vdso_end,
+ .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
+ .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
+ },
+#ifdef CONFIG_COMPAT
+ [VDSO_ABI_RV32] = {
+ .name = "compat_vdso",
+ .vdso_code_start = compat_vdso_start,
+ .vdso_code_end = compat_vdso_end,
+ .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
+ .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
+ },
+#endif
};
+
+static void __init __vdso_init(enum vdso_abi abi)
+{
+ unsigned int i;
+ struct page **vdso_pagelist;
+ unsigned long pfn;
+
+ if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
+ panic("vDSO is not a valid ELF object!\n");
+
+ vdso_info[abi].vdso_pages = (
+ vdso_info[abi].vdso_code_end -
+ vdso_info[abi].vdso_code_start) >>
+ PAGE_SHIFT;
+
+ vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
+ sizeof(struct page *),
+ GFP_KERNEL);
+ if (vdso_pagelist == NULL)
+ panic("vDSO kcalloc failed!\n");
+
+ /* Grab the vDSO code pages. */
+ pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
+
+ for (i = 0; i < vdso_info[abi].vdso_pages; i++)
+ vdso_pagelist[i] = pfn_to_page(pfn + i);
+
+ vdso_info[abi].cm->pages = vdso_pagelist;
+}
+
+#ifdef CONFIG_TIME_NS
+struct vdso_data *arch_get_vdso_data(void *vvar_page)
+{
+ return (struct vdso_data *)(vvar_page);
+}
+
+/*
+ * The vvar mapping contains data for a specific time namespace, so when a task
+ * changes namespace we must unmap its vvar data for the old namespace.
+ * Subsequent faults will map in data for the new namespace.
+ *
+ * For more details see timens_setup_vdso_data().
+ */
+int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma;
+
+ mmap_read_lock(mm);
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ unsigned long size = vma->vm_end - vma->vm_start;
+
+ if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
+ zap_page_range(vma, vma->vm_start, size);
+#ifdef CONFIG_COMPAT
+ if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
+ zap_page_range(vma, vma->vm_start, size);
+#endif
+ }
+
+ mmap_read_unlock(mm);
+ return 0;
+}
#endif
static int __init vdso_init(void)
{
- __vdso_init(&vdso_info);
+ __vdso_init(VDSO_ABI_RV64);
#ifdef CONFIG_COMPAT
- __vdso_init(&compat_vdso_info);
+ __vdso_init(VDSO_ABI_RV32);
#endif
return 0;
@@ -240,14 +254,14 @@ arch_initcall(vdso_init);
static int __setup_additional_pages(struct mm_struct *mm,
struct linux_binprm *bprm,
int uses_interp,
- struct __vdso_info *vdso_info)
+ enum vdso_abi abi)
{
unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
void *ret;
BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
- vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
+ vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
/* Be sure to map the data page */
vdso_mapping_len = vdso_text_len + VVAR_SIZE;
@@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
}
ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
- (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
+ (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
if (IS_ERR(ret))
goto up_fail;
vdso_base += VVAR_SIZE;
mm->context.vdso = (void *)vdso_base;
- mm->context.vdso_info = (void *)vdso_info;
ret =
_install_special_mapping(mm, vdso_base, vdso_text_len,
(VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
- vdso_info->cm);
+ vdso_info[abi].cm);
if (IS_ERR(ret))
goto up_fail;
@@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
if (mmap_write_lock_killable(mm))
return -EINTR;
- ret = __setup_additional_pages(mm, bprm, uses_interp,
- &compat_vdso_info);
+ ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
mmap_write_unlock(mm);
return ret;
@@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
if (mmap_write_lock_killable(mm))
return -EINTR;
- ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
+ ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
mmap_write_unlock(mm);
return ret;
--
2.34.1
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
@ 2022-09-08 15:04 ` Jisheng Zhang
0 siblings, 0 replies; 10+ messages in thread
From: Jisheng Zhang @ 2022-09-08 15:04 UTC (permalink / raw)
To: Paul Walmsley, Palmer Dabbelt, Albert Ou, Guo Ren
Cc: linux-riscv, linux-kernel
Testing tools/testing/selftests/timens/vfork_exec.c got below
kernel log:
[ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
[ 6.842255] Oops [#1]
[ 6.842871] Modules linked in:
[ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
[ 6.845861] Hardware name: riscv-virtio,qemu (DT)
[ 6.848009] epc : vdso_join_timens+0xd2/0x110
[ 6.850097] ra : vdso_join_timens+0xd2/0x110
[ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
[ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
[ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
[ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
[ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
[ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
[ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
[ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
[ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
[ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
[ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
[ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
[ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
[ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
[ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
[ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
[ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
[ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
[ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
[ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
[ 6.877484] ---[ end trace 0000000000000000 ]---
This is because the mm->context.vdso_info is NULL in vfork case. From
another side, mm->context.vdso_info either points to vdso info
for RV64 or vdso info for compat, there's no need to bloat riscv's
mm_context_t, we can handle the difference when setup the additional
page for vdso.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
---
since v1:
- add "Fixes" tag
- fix build error when CONFIG_COMPAT is enabled.
arch/riscv/include/asm/mmu.h | 1 -
arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
2 files changed, 95 insertions(+), 84 deletions(-)
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
index cedcf8ea3c76..0099dc116168 100644
--- a/arch/riscv/include/asm/mmu.h
+++ b/arch/riscv/include/asm/mmu.h
@@ -16,7 +16,6 @@ typedef struct {
atomic_long_t id;
#endif
void *vdso;
- void *vdso_info;
#ifdef CONFIG_SMP
/* A local icache flush is needed before user execution can resume. */
cpumask_t icache_stale_mask;
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 69b05b6c181b..8ca3b821e1b5 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
extern char compat_vdso_start[], compat_vdso_end[];
#endif
+enum vdso_abi {
+ VDSO_ABI_RV64,
+ VDSO_ABI_RV32,
+};
+
enum vvar_pages {
VVAR_DATA_PAGE_OFFSET,
VVAR_TIMENS_PAGE_OFFSET,
@@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
return 0;
}
-static void __init __vdso_init(struct __vdso_info *vdso_info)
-{
- unsigned int i;
- struct page **vdso_pagelist;
- unsigned long pfn;
-
- if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
- panic("vDSO is not a valid ELF object!\n");
-
- vdso_info->vdso_pages = (
- vdso_info->vdso_code_end -
- vdso_info->vdso_code_start) >>
- PAGE_SHIFT;
-
- vdso_pagelist = kcalloc(vdso_info->vdso_pages,
- sizeof(struct page *),
- GFP_KERNEL);
- if (vdso_pagelist == NULL)
- panic("vDSO kcalloc failed!\n");
-
- /* Grab the vDSO code pages. */
- pfn = sym_to_pfn(vdso_info->vdso_code_start);
-
- for (i = 0; i < vdso_info->vdso_pages; i++)
- vdso_pagelist[i] = pfn_to_page(pfn + i);
-
- vdso_info->cm->pages = vdso_pagelist;
-}
-
#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)(vvar_page);
-}
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a task
- * changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- struct vm_area_struct *vma;
- struct __vdso_info *vdso_info = mm->context.vdso_info;
-
- mmap_read_lock(mm);
-
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
- unsigned long size = vma->vm_end - vma->vm_start;
-
- if (vma_is_special_mapping(vma, vdso_info->dm))
- zap_page_range(vma, vma->vm_start, size);
- }
-
- mmap_read_unlock(mm);
- return 0;
-}
-
static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
{
if (likely(vma->vm_mm == current->mm))
@@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
},
};
-static struct __vdso_info vdso_info __ro_after_init = {
- .name = "vdso",
- .vdso_code_start = vdso_start,
- .vdso_code_end = vdso_end,
- .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
- .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
-};
#ifdef CONFIG_COMPAT
static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
@@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
.mremap = vdso_mremap,
},
};
+#endif
-static struct __vdso_info compat_vdso_info __ro_after_init = {
- .name = "compat_vdso",
- .vdso_code_start = compat_vdso_start,
- .vdso_code_end = compat_vdso_end,
- .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
- .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
+static struct __vdso_info vdso_info[] __ro_after_init = {
+ [VDSO_ABI_RV64] = {
+ .name = "vdso",
+ .vdso_code_start = vdso_start,
+ .vdso_code_end = vdso_end,
+ .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
+ .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
+ },
+#ifdef CONFIG_COMPAT
+ [VDSO_ABI_RV32] = {
+ .name = "compat_vdso",
+ .vdso_code_start = compat_vdso_start,
+ .vdso_code_end = compat_vdso_end,
+ .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
+ .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
+ },
+#endif
};
+
+static void __init __vdso_init(enum vdso_abi abi)
+{
+ unsigned int i;
+ struct page **vdso_pagelist;
+ unsigned long pfn;
+
+ if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
+ panic("vDSO is not a valid ELF object!\n");
+
+ vdso_info[abi].vdso_pages = (
+ vdso_info[abi].vdso_code_end -
+ vdso_info[abi].vdso_code_start) >>
+ PAGE_SHIFT;
+
+ vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
+ sizeof(struct page *),
+ GFP_KERNEL);
+ if (vdso_pagelist == NULL)
+ panic("vDSO kcalloc failed!\n");
+
+ /* Grab the vDSO code pages. */
+ pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
+
+ for (i = 0; i < vdso_info[abi].vdso_pages; i++)
+ vdso_pagelist[i] = pfn_to_page(pfn + i);
+
+ vdso_info[abi].cm->pages = vdso_pagelist;
+}
+
+#ifdef CONFIG_TIME_NS
+struct vdso_data *arch_get_vdso_data(void *vvar_page)
+{
+ return (struct vdso_data *)(vvar_page);
+}
+
+/*
+ * The vvar mapping contains data for a specific time namespace, so when a task
+ * changes namespace we must unmap its vvar data for the old namespace.
+ * Subsequent faults will map in data for the new namespace.
+ *
+ * For more details see timens_setup_vdso_data().
+ */
+int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma;
+
+ mmap_read_lock(mm);
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ unsigned long size = vma->vm_end - vma->vm_start;
+
+ if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
+ zap_page_range(vma, vma->vm_start, size);
+#ifdef CONFIG_COMPAT
+ if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
+ zap_page_range(vma, vma->vm_start, size);
+#endif
+ }
+
+ mmap_read_unlock(mm);
+ return 0;
+}
#endif
static int __init vdso_init(void)
{
- __vdso_init(&vdso_info);
+ __vdso_init(VDSO_ABI_RV64);
#ifdef CONFIG_COMPAT
- __vdso_init(&compat_vdso_info);
+ __vdso_init(VDSO_ABI_RV32);
#endif
return 0;
@@ -240,14 +254,14 @@ arch_initcall(vdso_init);
static int __setup_additional_pages(struct mm_struct *mm,
struct linux_binprm *bprm,
int uses_interp,
- struct __vdso_info *vdso_info)
+ enum vdso_abi abi)
{
unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
void *ret;
BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
- vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
+ vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
/* Be sure to map the data page */
vdso_mapping_len = vdso_text_len + VVAR_SIZE;
@@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
}
ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
- (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
+ (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
if (IS_ERR(ret))
goto up_fail;
vdso_base += VVAR_SIZE;
mm->context.vdso = (void *)vdso_base;
- mm->context.vdso_info = (void *)vdso_info;
ret =
_install_special_mapping(mm, vdso_base, vdso_text_len,
(VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
- vdso_info->cm);
+ vdso_info[abi].cm);
if (IS_ERR(ret))
goto up_fail;
@@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
if (mmap_write_lock_killable(mm))
return -EINTR;
- ret = __setup_additional_pages(mm, bprm, uses_interp,
- &compat_vdso_info);
+ ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
mmap_write_unlock(mm);
return ret;
@@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
if (mmap_write_lock_killable(mm))
return -EINTR;
- ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
+ ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
mmap_write_unlock(mm);
return ret;
--
2.34.1
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
2022-09-08 15:04 ` Jisheng Zhang
@ 2022-09-09 3:48 ` Guo Ren
-1 siblings, 0 replies; 10+ messages in thread
From: Guo Ren @ 2022-09-09 3:48 UTC (permalink / raw)
To: Jisheng Zhang
Cc: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv, linux-kernel
Great job! I've tested it on rv32-rootfs, and everything seems to be working.
Tested-by: Guo Ren <guoren@kernel.org>
On Thu, Sep 8, 2022 at 11:13 PM Jisheng Zhang <jszhang@kernel.org> wrote:
>
> Testing tools/testing/selftests/timens/vfork_exec.c got below
> kernel log:
>
> [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
> [ 6.842255] Oops [#1]
> [ 6.842871] Modules linked in:
> [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
> [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
> [ 6.848009] epc : vdso_join_timens+0xd2/0x110
> [ 6.850097] ra : vdso_join_timens+0xd2/0x110
> [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
> [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
> [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
> [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
> [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
> [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
> [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
> [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
> [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
> [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
> [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
> [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
> [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
> [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
> [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
> [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
> [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
> [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
> [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
> [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
> [ 6.877484] ---[ end trace 0000000000000000 ]---
>
> This is because the mm->context.vdso_info is NULL in vfork case. From
> another side, mm->context.vdso_info either points to vdso info
> for RV64 or vdso info for compat, there's no need to bloat riscv's
> mm_context_t, we can handle the difference when setup the additional
> page for vdso.
>
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
> ---
>
> since v1:
> - add "Fixes" tag
> - fix build error when CONFIG_COMPAT is enabled.
>
> arch/riscv/include/asm/mmu.h | 1 -
> arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
> 2 files changed, 95 insertions(+), 84 deletions(-)
>
> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> index cedcf8ea3c76..0099dc116168 100644
> --- a/arch/riscv/include/asm/mmu.h
> +++ b/arch/riscv/include/asm/mmu.h
> @@ -16,7 +16,6 @@ typedef struct {
> atomic_long_t id;
> #endif
> void *vdso;
> - void *vdso_info;
> #ifdef CONFIG_SMP
> /* A local icache flush is needed before user execution can resume. */
> cpumask_t icache_stale_mask;
> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> index 69b05b6c181b..8ca3b821e1b5 100644
> --- a/arch/riscv/kernel/vdso.c
> +++ b/arch/riscv/kernel/vdso.c
> @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
> extern char compat_vdso_start[], compat_vdso_end[];
> #endif
>
> +enum vdso_abi {
> + VDSO_ABI_RV64,
> + VDSO_ABI_RV32,
> +};
> +
> enum vvar_pages {
> VVAR_DATA_PAGE_OFFSET,
> VVAR_TIMENS_PAGE_OFFSET,
> @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
> return 0;
> }
>
> -static void __init __vdso_init(struct __vdso_info *vdso_info)
> -{
> - unsigned int i;
> - struct page **vdso_pagelist;
> - unsigned long pfn;
> -
> - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> - panic("vDSO is not a valid ELF object!\n");
> -
> - vdso_info->vdso_pages = (
> - vdso_info->vdso_code_end -
> - vdso_info->vdso_code_start) >>
> - PAGE_SHIFT;
> -
> - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> - sizeof(struct page *),
> - GFP_KERNEL);
> - if (vdso_pagelist == NULL)
> - panic("vDSO kcalloc failed!\n");
> -
> - /* Grab the vDSO code pages. */
> - pfn = sym_to_pfn(vdso_info->vdso_code_start);
> -
> - for (i = 0; i < vdso_info->vdso_pages; i++)
> - vdso_pagelist[i] = pfn_to_page(pfn + i);
> -
> - vdso_info->cm->pages = vdso_pagelist;
> -}
> -
> #ifdef CONFIG_TIME_NS
> -struct vdso_data *arch_get_vdso_data(void *vvar_page)
> -{
> - return (struct vdso_data *)(vvar_page);
> -}
> -
> -/*
> - * The vvar mapping contains data for a specific time namespace, so when a task
> - * changes namespace we must unmap its vvar data for the old namespace.
> - * Subsequent faults will map in data for the new namespace.
> - *
> - * For more details see timens_setup_vdso_data().
> - */
> -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> -{
> - struct mm_struct *mm = task->mm;
> - struct vm_area_struct *vma;
> - struct __vdso_info *vdso_info = mm->context.vdso_info;
> -
> - mmap_read_lock(mm);
> -
> - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> - unsigned long size = vma->vm_end - vma->vm_start;
> -
> - if (vma_is_special_mapping(vma, vdso_info->dm))
> - zap_page_range(vma, vma->vm_start, size);
> - }
> -
> - mmap_read_unlock(mm);
> - return 0;
> -}
> -
> static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
> {
> if (likely(vma->vm_mm == current->mm))
> @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
> },
> };
>
> -static struct __vdso_info vdso_info __ro_after_init = {
> - .name = "vdso",
> - .vdso_code_start = vdso_start,
> - .vdso_code_end = vdso_end,
> - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> -};
>
> #ifdef CONFIG_COMPAT
> static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> .mremap = vdso_mremap,
> },
> };
> +#endif
>
> -static struct __vdso_info compat_vdso_info __ro_after_init = {
> - .name = "compat_vdso",
> - .vdso_code_start = compat_vdso_start,
> - .vdso_code_end = compat_vdso_end,
> - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> +static struct __vdso_info vdso_info[] __ro_after_init = {
> + [VDSO_ABI_RV64] = {
> + .name = "vdso",
> + .vdso_code_start = vdso_start,
> + .vdso_code_end = vdso_end,
> + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#ifdef CONFIG_COMPAT
> + [VDSO_ABI_RV32] = {
> + .name = "compat_vdso",
> + .vdso_code_start = compat_vdso_start,
> + .vdso_code_end = compat_vdso_end,
> + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#endif
> };
> +
> +static void __init __vdso_init(enum vdso_abi abi)
> +{
> + unsigned int i;
> + struct page **vdso_pagelist;
> + unsigned long pfn;
> +
> + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
> + panic("vDSO is not a valid ELF object!\n");
> +
> + vdso_info[abi].vdso_pages = (
> + vdso_info[abi].vdso_code_end -
> + vdso_info[abi].vdso_code_start) >>
> + PAGE_SHIFT;
> +
> + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
> + sizeof(struct page *),
> + GFP_KERNEL);
> + if (vdso_pagelist == NULL)
> + panic("vDSO kcalloc failed!\n");
> +
> + /* Grab the vDSO code pages. */
> + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
> +
> + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
> + vdso_pagelist[i] = pfn_to_page(pfn + i);
> +
> + vdso_info[abi].cm->pages = vdso_pagelist;
> +}
> +
> +#ifdef CONFIG_TIME_NS
> +struct vdso_data *arch_get_vdso_data(void *vvar_page)
> +{
> + return (struct vdso_data *)(vvar_page);
> +}
> +
> +/*
> + * The vvar mapping contains data for a specific time namespace, so when a task
> + * changes namespace we must unmap its vvar data for the old namespace.
> + * Subsequent faults will map in data for the new namespace.
> + *
> + * For more details see timens_setup_vdso_data().
> + */
> +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> +{
> + struct mm_struct *mm = task->mm;
> + struct vm_area_struct *vma;
> +
> + mmap_read_lock(mm);
> +
> + for (vma = mm->mmap; vma; vma = vma->vm_next) {
> + unsigned long size = vma->vm_end - vma->vm_start;
> +
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#ifdef CONFIG_COMPAT
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#endif
> + }
> +
> + mmap_read_unlock(mm);
> + return 0;
> +}
> #endif
>
> static int __init vdso_init(void)
> {
> - __vdso_init(&vdso_info);
> + __vdso_init(VDSO_ABI_RV64);
> #ifdef CONFIG_COMPAT
> - __vdso_init(&compat_vdso_info);
> + __vdso_init(VDSO_ABI_RV32);
> #endif
>
> return 0;
> @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
> static int __setup_additional_pages(struct mm_struct *mm,
> struct linux_binprm *bprm,
> int uses_interp,
> - struct __vdso_info *vdso_info)
> + enum vdso_abi abi)
> {
> unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
> void *ret;
>
> BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
>
> - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
> + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
> /* Be sure to map the data page */
> vdso_mapping_len = vdso_text_len + VVAR_SIZE;
>
> @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
> }
>
> ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
> - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
> + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
> if (IS_ERR(ret))
> goto up_fail;
>
> vdso_base += VVAR_SIZE;
> mm->context.vdso = (void *)vdso_base;
> - mm->context.vdso_info = (void *)vdso_info;
>
> ret =
> _install_special_mapping(mm, vdso_base, vdso_text_len,
> (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
> - vdso_info->cm);
> + vdso_info[abi].cm);
>
> if (IS_ERR(ret))
> goto up_fail;
> @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp,
> - &compat_vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
> mmap_write_unlock(mm);
>
> return ret;
> @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
> mmap_write_unlock(mm);
>
> return ret;
> --
> 2.34.1
>
--
Best Regards
Guo Ren
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
@ 2022-09-09 3:48 ` Guo Ren
0 siblings, 0 replies; 10+ messages in thread
From: Guo Ren @ 2022-09-09 3:48 UTC (permalink / raw)
To: Jisheng Zhang
Cc: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv, linux-kernel
Great job! I've tested it on rv32-rootfs, and everything seems to be working.
Tested-by: Guo Ren <guoren@kernel.org>
On Thu, Sep 8, 2022 at 11:13 PM Jisheng Zhang <jszhang@kernel.org> wrote:
>
> Testing tools/testing/selftests/timens/vfork_exec.c got below
> kernel log:
>
> [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
> [ 6.842255] Oops [#1]
> [ 6.842871] Modules linked in:
> [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
> [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
> [ 6.848009] epc : vdso_join_timens+0xd2/0x110
> [ 6.850097] ra : vdso_join_timens+0xd2/0x110
> [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
> [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
> [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
> [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
> [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
> [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
> [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
> [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
> [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
> [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
> [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
> [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
> [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
> [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
> [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
> [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
> [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
> [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
> [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
> [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
> [ 6.877484] ---[ end trace 0000000000000000 ]---
>
> This is because the mm->context.vdso_info is NULL in vfork case. From
> another side, mm->context.vdso_info either points to vdso info
> for RV64 or vdso info for compat, there's no need to bloat riscv's
> mm_context_t, we can handle the difference when setup the additional
> page for vdso.
>
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
> ---
>
> since v1:
> - add "Fixes" tag
> - fix build error when CONFIG_COMPAT is enabled.
>
> arch/riscv/include/asm/mmu.h | 1 -
> arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
> 2 files changed, 95 insertions(+), 84 deletions(-)
>
> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> index cedcf8ea3c76..0099dc116168 100644
> --- a/arch/riscv/include/asm/mmu.h
> +++ b/arch/riscv/include/asm/mmu.h
> @@ -16,7 +16,6 @@ typedef struct {
> atomic_long_t id;
> #endif
> void *vdso;
> - void *vdso_info;
> #ifdef CONFIG_SMP
> /* A local icache flush is needed before user execution can resume. */
> cpumask_t icache_stale_mask;
> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> index 69b05b6c181b..8ca3b821e1b5 100644
> --- a/arch/riscv/kernel/vdso.c
> +++ b/arch/riscv/kernel/vdso.c
> @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
> extern char compat_vdso_start[], compat_vdso_end[];
> #endif
>
> +enum vdso_abi {
> + VDSO_ABI_RV64,
> + VDSO_ABI_RV32,
> +};
> +
> enum vvar_pages {
> VVAR_DATA_PAGE_OFFSET,
> VVAR_TIMENS_PAGE_OFFSET,
> @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
> return 0;
> }
>
> -static void __init __vdso_init(struct __vdso_info *vdso_info)
> -{
> - unsigned int i;
> - struct page **vdso_pagelist;
> - unsigned long pfn;
> -
> - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> - panic("vDSO is not a valid ELF object!\n");
> -
> - vdso_info->vdso_pages = (
> - vdso_info->vdso_code_end -
> - vdso_info->vdso_code_start) >>
> - PAGE_SHIFT;
> -
> - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> - sizeof(struct page *),
> - GFP_KERNEL);
> - if (vdso_pagelist == NULL)
> - panic("vDSO kcalloc failed!\n");
> -
> - /* Grab the vDSO code pages. */
> - pfn = sym_to_pfn(vdso_info->vdso_code_start);
> -
> - for (i = 0; i < vdso_info->vdso_pages; i++)
> - vdso_pagelist[i] = pfn_to_page(pfn + i);
> -
> - vdso_info->cm->pages = vdso_pagelist;
> -}
> -
> #ifdef CONFIG_TIME_NS
> -struct vdso_data *arch_get_vdso_data(void *vvar_page)
> -{
> - return (struct vdso_data *)(vvar_page);
> -}
> -
> -/*
> - * The vvar mapping contains data for a specific time namespace, so when a task
> - * changes namespace we must unmap its vvar data for the old namespace.
> - * Subsequent faults will map in data for the new namespace.
> - *
> - * For more details see timens_setup_vdso_data().
> - */
> -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> -{
> - struct mm_struct *mm = task->mm;
> - struct vm_area_struct *vma;
> - struct __vdso_info *vdso_info = mm->context.vdso_info;
> -
> - mmap_read_lock(mm);
> -
> - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> - unsigned long size = vma->vm_end - vma->vm_start;
> -
> - if (vma_is_special_mapping(vma, vdso_info->dm))
> - zap_page_range(vma, vma->vm_start, size);
> - }
> -
> - mmap_read_unlock(mm);
> - return 0;
> -}
> -
> static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
> {
> if (likely(vma->vm_mm == current->mm))
> @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
> },
> };
>
> -static struct __vdso_info vdso_info __ro_after_init = {
> - .name = "vdso",
> - .vdso_code_start = vdso_start,
> - .vdso_code_end = vdso_end,
> - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> -};
>
> #ifdef CONFIG_COMPAT
> static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> .mremap = vdso_mremap,
> },
> };
> +#endif
>
> -static struct __vdso_info compat_vdso_info __ro_after_init = {
> - .name = "compat_vdso",
> - .vdso_code_start = compat_vdso_start,
> - .vdso_code_end = compat_vdso_end,
> - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> +static struct __vdso_info vdso_info[] __ro_after_init = {
> + [VDSO_ABI_RV64] = {
> + .name = "vdso",
> + .vdso_code_start = vdso_start,
> + .vdso_code_end = vdso_end,
> + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#ifdef CONFIG_COMPAT
> + [VDSO_ABI_RV32] = {
> + .name = "compat_vdso",
> + .vdso_code_start = compat_vdso_start,
> + .vdso_code_end = compat_vdso_end,
> + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#endif
> };
> +
> +static void __init __vdso_init(enum vdso_abi abi)
> +{
> + unsigned int i;
> + struct page **vdso_pagelist;
> + unsigned long pfn;
> +
> + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
> + panic("vDSO is not a valid ELF object!\n");
> +
> + vdso_info[abi].vdso_pages = (
> + vdso_info[abi].vdso_code_end -
> + vdso_info[abi].vdso_code_start) >>
> + PAGE_SHIFT;
> +
> + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
> + sizeof(struct page *),
> + GFP_KERNEL);
> + if (vdso_pagelist == NULL)
> + panic("vDSO kcalloc failed!\n");
> +
> + /* Grab the vDSO code pages. */
> + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
> +
> + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
> + vdso_pagelist[i] = pfn_to_page(pfn + i);
> +
> + vdso_info[abi].cm->pages = vdso_pagelist;
> +}
> +
> +#ifdef CONFIG_TIME_NS
> +struct vdso_data *arch_get_vdso_data(void *vvar_page)
> +{
> + return (struct vdso_data *)(vvar_page);
> +}
> +
> +/*
> + * The vvar mapping contains data for a specific time namespace, so when a task
> + * changes namespace we must unmap its vvar data for the old namespace.
> + * Subsequent faults will map in data for the new namespace.
> + *
> + * For more details see timens_setup_vdso_data().
> + */
> +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> +{
> + struct mm_struct *mm = task->mm;
> + struct vm_area_struct *vma;
> +
> + mmap_read_lock(mm);
> +
> + for (vma = mm->mmap; vma; vma = vma->vm_next) {
> + unsigned long size = vma->vm_end - vma->vm_start;
> +
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#ifdef CONFIG_COMPAT
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#endif
> + }
> +
> + mmap_read_unlock(mm);
> + return 0;
> +}
> #endif
>
> static int __init vdso_init(void)
> {
> - __vdso_init(&vdso_info);
> + __vdso_init(VDSO_ABI_RV64);
> #ifdef CONFIG_COMPAT
> - __vdso_init(&compat_vdso_info);
> + __vdso_init(VDSO_ABI_RV32);
> #endif
>
> return 0;
> @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
> static int __setup_additional_pages(struct mm_struct *mm,
> struct linux_binprm *bprm,
> int uses_interp,
> - struct __vdso_info *vdso_info)
> + enum vdso_abi abi)
> {
> unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
> void *ret;
>
> BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
>
> - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
> + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
> /* Be sure to map the data page */
> vdso_mapping_len = vdso_text_len + VVAR_SIZE;
>
> @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
> }
>
> ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
> - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
> + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
> if (IS_ERR(ret))
> goto up_fail;
>
> vdso_base += VVAR_SIZE;
> mm->context.vdso = (void *)vdso_base;
> - mm->context.vdso_info = (void *)vdso_info;
>
> ret =
> _install_special_mapping(mm, vdso_base, vdso_text_len,
> (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
> - vdso_info->cm);
> + vdso_info[abi].cm);
>
> if (IS_ERR(ret))
> goto up_fail;
> @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp,
> - &compat_vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
> mmap_write_unlock(mm);
>
> return ret;
> @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
> mmap_write_unlock(mm);
>
> return ret;
> --
> 2.34.1
>
--
Best Regards
Guo Ren
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
2022-09-08 15:04 ` Jisheng Zhang
@ 2022-09-15 18:02 ` Palmer Dabbelt
-1 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2022-09-15 18:02 UTC (permalink / raw)
To: jszhang; +Cc: Paul Walmsley, aou, guoren, linux-riscv, linux-kernel
On Thu, 08 Sep 2022 08:04:21 PDT (-0700), jszhang@kernel.org wrote:
> Testing tools/testing/selftests/timens/vfork_exec.c got below
> kernel log:
>
> [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
> [ 6.842255] Oops [#1]
> [ 6.842871] Modules linked in:
> [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
> [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
> [ 6.848009] epc : vdso_join_timens+0xd2/0x110
> [ 6.850097] ra : vdso_join_timens+0xd2/0x110
> [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
> [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
> [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
> [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
> [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
> [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
> [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
> [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
> [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
> [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
> [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
> [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
> [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
> [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
> [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
> [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
> [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
> [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
> [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
> [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
> [ 6.877484] ---[ end trace 0000000000000000 ]---
>
> This is because the mm->context.vdso_info is NULL in vfork case. From
> another side, mm->context.vdso_info either points to vdso info
> for RV64 or vdso info for compat, there's no need to bloat riscv's
> mm_context_t, we can handle the difference when setup the additional
> page for vdso.
Makes sense, but I think there's a lot more diff here than we need in
order to just fix the bug. Does something like the following still fix
it? Also at kernel.org/palmer/vdso-fix-v3 . Maybe it's a bit pedantic
, but this late in the cycle with everyone traveling I'd prefer to keep
the fixes smaller when possible.
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
index cedcf8ea3c76..0099dc116168 100644
--- a/arch/riscv/include/asm/mmu.h
+++ b/arch/riscv/include/asm/mmu.h
@@ -16,7 +16,6 @@ typedef struct {
atomic_long_t id;
#endif
void *vdso;
- void *vdso_info;
#ifdef CONFIG_SMP
/* A local icache flush is needed before user execution can resume. */
cpumask_t icache_stale_mask;
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 69b05b6c181b..58b8d73a4b1f 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -23,8 +23,10 @@ struct vdso_data {
#endif
extern char vdso_start[], vdso_end[];
+static struct __vdso_info vdso_info;
#ifdef CONFIG_COMPAT
extern char compat_vdso_start[], compat_vdso_end[];
+static struct __vdso_info compat_vdso_info;
#endif
enum vvar_pages {
@@ -114,15 +116,18 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
{
struct mm_struct *mm = task->mm;
struct vm_area_struct *vma;
- struct __vdso_info *vdso_info = mm->context.vdso_info;
mmap_read_lock(mm);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
unsigned long size = vma->vm_end - vma->vm_start;
- if (vma_is_special_mapping(vma, vdso_info->dm))
+ if (vma_is_special_mapping(vma, vdso_info.dm))
zap_page_range(vma, vma->vm_start, size);
+#ifdef CONFIG_COMPAT
+ if (vma_is_special_mapping(vma, compat_vdso_info.dm))
+ zap_page_range(vma, vma->vm_start, size);
+#endif
}
mmap_read_unlock(mm);
@@ -264,7 +269,6 @@ static int __setup_additional_pages(struct mm_struct *mm,
vdso_base += VVAR_SIZE;
mm->context.vdso = (void *)vdso_base;
- mm->context.vdso_info = (void *)vdso_info;
ret =
_install_special_mapping(mm, vdso_base, vdso_text_len,
>
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
> ---
>
> since v1:
> - add "Fixes" tag
> - fix build error when CONFIG_COMPAT is enabled.
>
> arch/riscv/include/asm/mmu.h | 1 -
> arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
> 2 files changed, 95 insertions(+), 84 deletions(-)
>
> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> index cedcf8ea3c76..0099dc116168 100644
> --- a/arch/riscv/include/asm/mmu.h
> +++ b/arch/riscv/include/asm/mmu.h
> @@ -16,7 +16,6 @@ typedef struct {
> atomic_long_t id;
> #endif
> void *vdso;
> - void *vdso_info;
> #ifdef CONFIG_SMP
> /* A local icache flush is needed before user execution can resume. */
> cpumask_t icache_stale_mask;
> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> index 69b05b6c181b..8ca3b821e1b5 100644
> --- a/arch/riscv/kernel/vdso.c
> +++ b/arch/riscv/kernel/vdso.c
> @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
> extern char compat_vdso_start[], compat_vdso_end[];
> #endif
>
> +enum vdso_abi {
> + VDSO_ABI_RV64,
> + VDSO_ABI_RV32,
> +};
> +
> enum vvar_pages {
> VVAR_DATA_PAGE_OFFSET,
> VVAR_TIMENS_PAGE_OFFSET,
> @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
> return 0;
> }
>
> -static void __init __vdso_init(struct __vdso_info *vdso_info)
> -{
> - unsigned int i;
> - struct page **vdso_pagelist;
> - unsigned long pfn;
> -
> - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> - panic("vDSO is not a valid ELF object!\n");
> -
> - vdso_info->vdso_pages = (
> - vdso_info->vdso_code_end -
> - vdso_info->vdso_code_start) >>
> - PAGE_SHIFT;
> -
> - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> - sizeof(struct page *),
> - GFP_KERNEL);
> - if (vdso_pagelist == NULL)
> - panic("vDSO kcalloc failed!\n");
> -
> - /* Grab the vDSO code pages. */
> - pfn = sym_to_pfn(vdso_info->vdso_code_start);
> -
> - for (i = 0; i < vdso_info->vdso_pages; i++)
> - vdso_pagelist[i] = pfn_to_page(pfn + i);
> -
> - vdso_info->cm->pages = vdso_pagelist;
> -}
> -
> #ifdef CONFIG_TIME_NS
> -struct vdso_data *arch_get_vdso_data(void *vvar_page)
> -{
> - return (struct vdso_data *)(vvar_page);
> -}
> -
> -/*
> - * The vvar mapping contains data for a specific time namespace, so when a task
> - * changes namespace we must unmap its vvar data for the old namespace.
> - * Subsequent faults will map in data for the new namespace.
> - *
> - * For more details see timens_setup_vdso_data().
> - */
> -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> -{
> - struct mm_struct *mm = task->mm;
> - struct vm_area_struct *vma;
> - struct __vdso_info *vdso_info = mm->context.vdso_info;
> -
> - mmap_read_lock(mm);
> -
> - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> - unsigned long size = vma->vm_end - vma->vm_start;
> -
> - if (vma_is_special_mapping(vma, vdso_info->dm))
> - zap_page_range(vma, vma->vm_start, size);
> - }
> -
> - mmap_read_unlock(mm);
> - return 0;
> -}
> -
> static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
> {
> if (likely(vma->vm_mm == current->mm))
> @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
> },
> };
>
> -static struct __vdso_info vdso_info __ro_after_init = {
> - .name = "vdso",
> - .vdso_code_start = vdso_start,
> - .vdso_code_end = vdso_end,
> - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> -};
>
> #ifdef CONFIG_COMPAT
> static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> .mremap = vdso_mremap,
> },
> };
> +#endif
>
> -static struct __vdso_info compat_vdso_info __ro_after_init = {
> - .name = "compat_vdso",
> - .vdso_code_start = compat_vdso_start,
> - .vdso_code_end = compat_vdso_end,
> - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> +static struct __vdso_info vdso_info[] __ro_after_init = {
> + [VDSO_ABI_RV64] = {
> + .name = "vdso",
> + .vdso_code_start = vdso_start,
> + .vdso_code_end = vdso_end,
> + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#ifdef CONFIG_COMPAT
> + [VDSO_ABI_RV32] = {
> + .name = "compat_vdso",
> + .vdso_code_start = compat_vdso_start,
> + .vdso_code_end = compat_vdso_end,
> + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#endif
> };
> +
> +static void __init __vdso_init(enum vdso_abi abi)
> +{
> + unsigned int i;
> + struct page **vdso_pagelist;
> + unsigned long pfn;
> +
> + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
> + panic("vDSO is not a valid ELF object!\n");
> +
> + vdso_info[abi].vdso_pages = (
> + vdso_info[abi].vdso_code_end -
> + vdso_info[abi].vdso_code_start) >>
> + PAGE_SHIFT;
> +
> + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
> + sizeof(struct page *),
> + GFP_KERNEL);
> + if (vdso_pagelist == NULL)
> + panic("vDSO kcalloc failed!\n");
> +
> + /* Grab the vDSO code pages. */
> + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
> +
> + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
> + vdso_pagelist[i] = pfn_to_page(pfn + i);
> +
> + vdso_info[abi].cm->pages = vdso_pagelist;
> +}
> +
> +#ifdef CONFIG_TIME_NS
> +struct vdso_data *arch_get_vdso_data(void *vvar_page)
> +{
> + return (struct vdso_data *)(vvar_page);
> +}
> +
> +/*
> + * The vvar mapping contains data for a specific time namespace, so when a task
> + * changes namespace we must unmap its vvar data for the old namespace.
> + * Subsequent faults will map in data for the new namespace.
> + *
> + * For more details see timens_setup_vdso_data().
> + */
> +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> +{
> + struct mm_struct *mm = task->mm;
> + struct vm_area_struct *vma;
> +
> + mmap_read_lock(mm);
> +
> + for (vma = mm->mmap; vma; vma = vma->vm_next) {
> + unsigned long size = vma->vm_end - vma->vm_start;
> +
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#ifdef CONFIG_COMPAT
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#endif
> + }
> +
> + mmap_read_unlock(mm);
> + return 0;
> +}
> #endif
>
> static int __init vdso_init(void)
> {
> - __vdso_init(&vdso_info);
> + __vdso_init(VDSO_ABI_RV64);
> #ifdef CONFIG_COMPAT
> - __vdso_init(&compat_vdso_info);
> + __vdso_init(VDSO_ABI_RV32);
> #endif
>
> return 0;
> @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
> static int __setup_additional_pages(struct mm_struct *mm,
> struct linux_binprm *bprm,
> int uses_interp,
> - struct __vdso_info *vdso_info)
> + enum vdso_abi abi)
> {
> unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
> void *ret;
>
> BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
>
> - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
> + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
> /* Be sure to map the data page */
> vdso_mapping_len = vdso_text_len + VVAR_SIZE;
>
> @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
> }
>
> ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
> - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
> + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
> if (IS_ERR(ret))
> goto up_fail;
>
> vdso_base += VVAR_SIZE;
> mm->context.vdso = (void *)vdso_base;
> - mm->context.vdso_info = (void *)vdso_info;
>
> ret =
> _install_special_mapping(mm, vdso_base, vdso_text_len,
> (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
> - vdso_info->cm);
> + vdso_info[abi].cm);
>
> if (IS_ERR(ret))
> goto up_fail;
> @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp,
> - &compat_vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
> mmap_write_unlock(mm);
>
> return ret;
> @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
> mmap_write_unlock(mm);
>
> return ret;
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
@ 2022-09-15 18:02 ` Palmer Dabbelt
0 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2022-09-15 18:02 UTC (permalink / raw)
To: jszhang; +Cc: Paul Walmsley, aou, guoren, linux-riscv, linux-kernel
On Thu, 08 Sep 2022 08:04:21 PDT (-0700), jszhang@kernel.org wrote:
> Testing tools/testing/selftests/timens/vfork_exec.c got below
> kernel log:
>
> [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
> [ 6.842255] Oops [#1]
> [ 6.842871] Modules linked in:
> [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
> [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
> [ 6.848009] epc : vdso_join_timens+0xd2/0x110
> [ 6.850097] ra : vdso_join_timens+0xd2/0x110
> [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
> [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
> [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
> [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
> [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
> [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
> [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
> [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
> [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
> [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
> [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
> [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
> [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
> [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
> [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
> [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
> [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
> [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
> [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
> [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
> [ 6.877484] ---[ end trace 0000000000000000 ]---
>
> This is because the mm->context.vdso_info is NULL in vfork case. From
> another side, mm->context.vdso_info either points to vdso info
> for RV64 or vdso info for compat, there's no need to bloat riscv's
> mm_context_t, we can handle the difference when setup the additional
> page for vdso.
Makes sense, but I think there's a lot more diff here than we need in
order to just fix the bug. Does something like the following still fix
it? Also at kernel.org/palmer/vdso-fix-v3 . Maybe it's a bit pedantic
, but this late in the cycle with everyone traveling I'd prefer to keep
the fixes smaller when possible.
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
index cedcf8ea3c76..0099dc116168 100644
--- a/arch/riscv/include/asm/mmu.h
+++ b/arch/riscv/include/asm/mmu.h
@@ -16,7 +16,6 @@ typedef struct {
atomic_long_t id;
#endif
void *vdso;
- void *vdso_info;
#ifdef CONFIG_SMP
/* A local icache flush is needed before user execution can resume. */
cpumask_t icache_stale_mask;
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 69b05b6c181b..58b8d73a4b1f 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -23,8 +23,10 @@ struct vdso_data {
#endif
extern char vdso_start[], vdso_end[];
+static struct __vdso_info vdso_info;
#ifdef CONFIG_COMPAT
extern char compat_vdso_start[], compat_vdso_end[];
+static struct __vdso_info compat_vdso_info;
#endif
enum vvar_pages {
@@ -114,15 +116,18 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
{
struct mm_struct *mm = task->mm;
struct vm_area_struct *vma;
- struct __vdso_info *vdso_info = mm->context.vdso_info;
mmap_read_lock(mm);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
unsigned long size = vma->vm_end - vma->vm_start;
- if (vma_is_special_mapping(vma, vdso_info->dm))
+ if (vma_is_special_mapping(vma, vdso_info.dm))
zap_page_range(vma, vma->vm_start, size);
+#ifdef CONFIG_COMPAT
+ if (vma_is_special_mapping(vma, compat_vdso_info.dm))
+ zap_page_range(vma, vma->vm_start, size);
+#endif
}
mmap_read_unlock(mm);
@@ -264,7 +269,6 @@ static int __setup_additional_pages(struct mm_struct *mm,
vdso_base += VVAR_SIZE;
mm->context.vdso = (void *)vdso_base;
- mm->context.vdso_info = (void *)vdso_info;
ret =
_install_special_mapping(mm, vdso_base, vdso_text_len,
>
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
> ---
>
> since v1:
> - add "Fixes" tag
> - fix build error when CONFIG_COMPAT is enabled.
>
> arch/riscv/include/asm/mmu.h | 1 -
> arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
> 2 files changed, 95 insertions(+), 84 deletions(-)
>
> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> index cedcf8ea3c76..0099dc116168 100644
> --- a/arch/riscv/include/asm/mmu.h
> +++ b/arch/riscv/include/asm/mmu.h
> @@ -16,7 +16,6 @@ typedef struct {
> atomic_long_t id;
> #endif
> void *vdso;
> - void *vdso_info;
> #ifdef CONFIG_SMP
> /* A local icache flush is needed before user execution can resume. */
> cpumask_t icache_stale_mask;
> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> index 69b05b6c181b..8ca3b821e1b5 100644
> --- a/arch/riscv/kernel/vdso.c
> +++ b/arch/riscv/kernel/vdso.c
> @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
> extern char compat_vdso_start[], compat_vdso_end[];
> #endif
>
> +enum vdso_abi {
> + VDSO_ABI_RV64,
> + VDSO_ABI_RV32,
> +};
> +
> enum vvar_pages {
> VVAR_DATA_PAGE_OFFSET,
> VVAR_TIMENS_PAGE_OFFSET,
> @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
> return 0;
> }
>
> -static void __init __vdso_init(struct __vdso_info *vdso_info)
> -{
> - unsigned int i;
> - struct page **vdso_pagelist;
> - unsigned long pfn;
> -
> - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> - panic("vDSO is not a valid ELF object!\n");
> -
> - vdso_info->vdso_pages = (
> - vdso_info->vdso_code_end -
> - vdso_info->vdso_code_start) >>
> - PAGE_SHIFT;
> -
> - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> - sizeof(struct page *),
> - GFP_KERNEL);
> - if (vdso_pagelist == NULL)
> - panic("vDSO kcalloc failed!\n");
> -
> - /* Grab the vDSO code pages. */
> - pfn = sym_to_pfn(vdso_info->vdso_code_start);
> -
> - for (i = 0; i < vdso_info->vdso_pages; i++)
> - vdso_pagelist[i] = pfn_to_page(pfn + i);
> -
> - vdso_info->cm->pages = vdso_pagelist;
> -}
> -
> #ifdef CONFIG_TIME_NS
> -struct vdso_data *arch_get_vdso_data(void *vvar_page)
> -{
> - return (struct vdso_data *)(vvar_page);
> -}
> -
> -/*
> - * The vvar mapping contains data for a specific time namespace, so when a task
> - * changes namespace we must unmap its vvar data for the old namespace.
> - * Subsequent faults will map in data for the new namespace.
> - *
> - * For more details see timens_setup_vdso_data().
> - */
> -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> -{
> - struct mm_struct *mm = task->mm;
> - struct vm_area_struct *vma;
> - struct __vdso_info *vdso_info = mm->context.vdso_info;
> -
> - mmap_read_lock(mm);
> -
> - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> - unsigned long size = vma->vm_end - vma->vm_start;
> -
> - if (vma_is_special_mapping(vma, vdso_info->dm))
> - zap_page_range(vma, vma->vm_start, size);
> - }
> -
> - mmap_read_unlock(mm);
> - return 0;
> -}
> -
> static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
> {
> if (likely(vma->vm_mm == current->mm))
> @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
> },
> };
>
> -static struct __vdso_info vdso_info __ro_after_init = {
> - .name = "vdso",
> - .vdso_code_start = vdso_start,
> - .vdso_code_end = vdso_end,
> - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> -};
>
> #ifdef CONFIG_COMPAT
> static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> .mremap = vdso_mremap,
> },
> };
> +#endif
>
> -static struct __vdso_info compat_vdso_info __ro_after_init = {
> - .name = "compat_vdso",
> - .vdso_code_start = compat_vdso_start,
> - .vdso_code_end = compat_vdso_end,
> - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> +static struct __vdso_info vdso_info[] __ro_after_init = {
> + [VDSO_ABI_RV64] = {
> + .name = "vdso",
> + .vdso_code_start = vdso_start,
> + .vdso_code_end = vdso_end,
> + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#ifdef CONFIG_COMPAT
> + [VDSO_ABI_RV32] = {
> + .name = "compat_vdso",
> + .vdso_code_start = compat_vdso_start,
> + .vdso_code_end = compat_vdso_end,
> + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> + },
> +#endif
> };
> +
> +static void __init __vdso_init(enum vdso_abi abi)
> +{
> + unsigned int i;
> + struct page **vdso_pagelist;
> + unsigned long pfn;
> +
> + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
> + panic("vDSO is not a valid ELF object!\n");
> +
> + vdso_info[abi].vdso_pages = (
> + vdso_info[abi].vdso_code_end -
> + vdso_info[abi].vdso_code_start) >>
> + PAGE_SHIFT;
> +
> + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
> + sizeof(struct page *),
> + GFP_KERNEL);
> + if (vdso_pagelist == NULL)
> + panic("vDSO kcalloc failed!\n");
> +
> + /* Grab the vDSO code pages. */
> + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
> +
> + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
> + vdso_pagelist[i] = pfn_to_page(pfn + i);
> +
> + vdso_info[abi].cm->pages = vdso_pagelist;
> +}
> +
> +#ifdef CONFIG_TIME_NS
> +struct vdso_data *arch_get_vdso_data(void *vvar_page)
> +{
> + return (struct vdso_data *)(vvar_page);
> +}
> +
> +/*
> + * The vvar mapping contains data for a specific time namespace, so when a task
> + * changes namespace we must unmap its vvar data for the old namespace.
> + * Subsequent faults will map in data for the new namespace.
> + *
> + * For more details see timens_setup_vdso_data().
> + */
> +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> +{
> + struct mm_struct *mm = task->mm;
> + struct vm_area_struct *vma;
> +
> + mmap_read_lock(mm);
> +
> + for (vma = mm->mmap; vma; vma = vma->vm_next) {
> + unsigned long size = vma->vm_end - vma->vm_start;
> +
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#ifdef CONFIG_COMPAT
> + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#endif
> + }
> +
> + mmap_read_unlock(mm);
> + return 0;
> +}
> #endif
>
> static int __init vdso_init(void)
> {
> - __vdso_init(&vdso_info);
> + __vdso_init(VDSO_ABI_RV64);
> #ifdef CONFIG_COMPAT
> - __vdso_init(&compat_vdso_info);
> + __vdso_init(VDSO_ABI_RV32);
> #endif
>
> return 0;
> @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
> static int __setup_additional_pages(struct mm_struct *mm,
> struct linux_binprm *bprm,
> int uses_interp,
> - struct __vdso_info *vdso_info)
> + enum vdso_abi abi)
> {
> unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
> void *ret;
>
> BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
>
> - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
> + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
> /* Be sure to map the data page */
> vdso_mapping_len = vdso_text_len + VVAR_SIZE;
>
> @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
> }
>
> ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
> - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
> + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
> if (IS_ERR(ret))
> goto up_fail;
>
> vdso_base += VVAR_SIZE;
> mm->context.vdso = (void *)vdso_base;
> - mm->context.vdso_info = (void *)vdso_info;
>
> ret =
> _install_special_mapping(mm, vdso_base, vdso_text_len,
> (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
> - vdso_info->cm);
> + vdso_info[abi].cm);
>
> if (IS_ERR(ret))
> goto up_fail;
> @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp,
> - &compat_vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
> mmap_write_unlock(mm);
>
> return ret;
> @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
> if (mmap_write_lock_killable(mm))
> return -EINTR;
>
> - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
> + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
> mmap_write_unlock(mm);
>
> return ret;
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
2022-09-15 18:02 ` Palmer Dabbelt
@ 2022-09-22 12:07 ` Jisheng Zhang
-1 siblings, 0 replies; 10+ messages in thread
From: Jisheng Zhang @ 2022-09-22 12:07 UTC (permalink / raw)
To: Palmer Dabbelt; +Cc: Paul Walmsley, aou, guoren, linux-riscv, linux-kernel
On Thu, Sep 15, 2022 at 11:02:19AM -0700, Palmer Dabbelt wrote:
> On Thu, 08 Sep 2022 08:04:21 PDT (-0700), jszhang@kernel.org wrote:
> > Testing tools/testing/selftests/timens/vfork_exec.c got below
> > kernel log:
> >
> > [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
> > [ 6.842255] Oops [#1]
> > [ 6.842871] Modules linked in:
> > [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
> > [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
> > [ 6.848009] epc : vdso_join_timens+0xd2/0x110
> > [ 6.850097] ra : vdso_join_timens+0xd2/0x110
> > [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
> > [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
> > [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
> > [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
> > [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
> > [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
> > [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
> > [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
> > [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
> > [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
> > [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
> > [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
> > [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
> > [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
> > [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
> > [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
> > [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
> > [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
> > [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
> > [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
> > [ 6.877484] ---[ end trace 0000000000000000 ]---
> >
> > This is because the mm->context.vdso_info is NULL in vfork case. From
> > another side, mm->context.vdso_info either points to vdso info
> > for RV64 or vdso info for compat, there's no need to bloat riscv's
> > mm_context_t, we can handle the difference when setup the additional
> > page for vdso.
>
> Makes sense, but I think there's a lot more diff here than we need in order
The reason of "a lot more diff" is moving the code to avoid forward declaration.
If you prefer smaller fix, I can provide a simpler one w/ forware
declaration. And provide a new clean up patch for next window, what do you
think?
Thanks
> to just fix the bug. Does something like the following still fix it? Also
> at kernel.org/palmer/vdso-fix-v3 . Maybe it's a bit pedantic , but this
> late in the cycle with everyone traveling I'd prefer to keep the fixes
> smaller when possible.
>
> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> index cedcf8ea3c76..0099dc116168 100644
> --- a/arch/riscv/include/asm/mmu.h
> +++ b/arch/riscv/include/asm/mmu.h
> @@ -16,7 +16,6 @@ typedef struct {
> atomic_long_t id;
> #endif
> void *vdso;
> - void *vdso_info;
> #ifdef CONFIG_SMP
> /* A local icache flush is needed before user execution can resume. */
> cpumask_t icache_stale_mask;
> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> index 69b05b6c181b..58b8d73a4b1f 100644
> --- a/arch/riscv/kernel/vdso.c
> +++ b/arch/riscv/kernel/vdso.c
> @@ -23,8 +23,10 @@ struct vdso_data {
> #endif
>
> extern char vdso_start[], vdso_end[];
> +static struct __vdso_info vdso_info;
> #ifdef CONFIG_COMPAT
> extern char compat_vdso_start[], compat_vdso_end[];
> +static struct __vdso_info compat_vdso_info;
> #endif
>
> enum vvar_pages {
> @@ -114,15 +116,18 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> {
> struct mm_struct *mm = task->mm;
> struct vm_area_struct *vma;
> - struct __vdso_info *vdso_info = mm->context.vdso_info;
>
> mmap_read_lock(mm);
>
> for (vma = mm->mmap; vma; vma = vma->vm_next) {
> unsigned long size = vma->vm_end - vma->vm_start;
>
> - if (vma_is_special_mapping(vma, vdso_info->dm))
> + if (vma_is_special_mapping(vma, vdso_info.dm))
> zap_page_range(vma, vma->vm_start, size);
> +#ifdef CONFIG_COMPAT
> + if (vma_is_special_mapping(vma, compat_vdso_info.dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#endif
> }
>
> mmap_read_unlock(mm);
> @@ -264,7 +269,6 @@ static int __setup_additional_pages(struct mm_struct *mm,
>
> vdso_base += VVAR_SIZE;
> mm->context.vdso = (void *)vdso_base;
> - mm->context.vdso_info = (void *)vdso_info;
>
> ret =
> _install_special_mapping(mm, vdso_base, vdso_text_len,
>
> >
> > Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> > Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
> > ---
> >
> > since v1:
> > - add "Fixes" tag
> > - fix build error when CONFIG_COMPAT is enabled.
> >
> > arch/riscv/include/asm/mmu.h | 1 -
> > arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
> > 2 files changed, 95 insertions(+), 84 deletions(-)
> >
> > diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> > index cedcf8ea3c76..0099dc116168 100644
> > --- a/arch/riscv/include/asm/mmu.h
> > +++ b/arch/riscv/include/asm/mmu.h
> > @@ -16,7 +16,6 @@ typedef struct {
> > atomic_long_t id;
> > #endif
> > void *vdso;
> > - void *vdso_info;
> > #ifdef CONFIG_SMP
> > /* A local icache flush is needed before user execution can resume. */
> > cpumask_t icache_stale_mask;
> > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> > index 69b05b6c181b..8ca3b821e1b5 100644
> > --- a/arch/riscv/kernel/vdso.c
> > +++ b/arch/riscv/kernel/vdso.c
> > @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
> > extern char compat_vdso_start[], compat_vdso_end[];
> > #endif
> >
> > +enum vdso_abi {
> > + VDSO_ABI_RV64,
> > + VDSO_ABI_RV32,
> > +};
> > +
> > enum vvar_pages {
> > VVAR_DATA_PAGE_OFFSET,
> > VVAR_TIMENS_PAGE_OFFSET,
> > @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
> > return 0;
> > }
> >
> > -static void __init __vdso_init(struct __vdso_info *vdso_info)
> > -{
> > - unsigned int i;
> > - struct page **vdso_pagelist;
> > - unsigned long pfn;
> > -
> > - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> > - panic("vDSO is not a valid ELF object!\n");
> > -
> > - vdso_info->vdso_pages = (
> > - vdso_info->vdso_code_end -
> > - vdso_info->vdso_code_start) >>
> > - PAGE_SHIFT;
> > -
> > - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> > - sizeof(struct page *),
> > - GFP_KERNEL);
> > - if (vdso_pagelist == NULL)
> > - panic("vDSO kcalloc failed!\n");
> > -
> > - /* Grab the vDSO code pages. */
> > - pfn = sym_to_pfn(vdso_info->vdso_code_start);
> > -
> > - for (i = 0; i < vdso_info->vdso_pages; i++)
> > - vdso_pagelist[i] = pfn_to_page(pfn + i);
> > -
> > - vdso_info->cm->pages = vdso_pagelist;
> > -}
> > -
> > #ifdef CONFIG_TIME_NS
> > -struct vdso_data *arch_get_vdso_data(void *vvar_page)
> > -{
> > - return (struct vdso_data *)(vvar_page);
> > -}
> > -
> > -/*
> > - * The vvar mapping contains data for a specific time namespace, so when a task
> > - * changes namespace we must unmap its vvar data for the old namespace.
> > - * Subsequent faults will map in data for the new namespace.
> > - *
> > - * For more details see timens_setup_vdso_data().
> > - */
> > -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> > -{
> > - struct mm_struct *mm = task->mm;
> > - struct vm_area_struct *vma;
> > - struct __vdso_info *vdso_info = mm->context.vdso_info;
> > -
> > - mmap_read_lock(mm);
> > -
> > - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> > - unsigned long size = vma->vm_end - vma->vm_start;
> > -
> > - if (vma_is_special_mapping(vma, vdso_info->dm))
> > - zap_page_range(vma, vma->vm_start, size);
> > - }
> > -
> > - mmap_read_unlock(mm);
> > - return 0;
> > -}
> > -
> > static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
> > {
> > if (likely(vma->vm_mm == current->mm))
> > @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
> > },
> > };
> >
> > -static struct __vdso_info vdso_info __ro_after_init = {
> > - .name = "vdso",
> > - .vdso_code_start = vdso_start,
> > - .vdso_code_end = vdso_end,
> > - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> > - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> > -};
> >
> > #ifdef CONFIG_COMPAT
> > static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> > @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> > .mremap = vdso_mremap,
> > },
> > };
> > +#endif
> >
> > -static struct __vdso_info compat_vdso_info __ro_after_init = {
> > - .name = "compat_vdso",
> > - .vdso_code_start = compat_vdso_start,
> > - .vdso_code_end = compat_vdso_end,
> > - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> > - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> > +static struct __vdso_info vdso_info[] __ro_after_init = {
> > + [VDSO_ABI_RV64] = {
> > + .name = "vdso",
> > + .vdso_code_start = vdso_start,
> > + .vdso_code_end = vdso_end,
> > + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> > + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> > + },
> > +#ifdef CONFIG_COMPAT
> > + [VDSO_ABI_RV32] = {
> > + .name = "compat_vdso",
> > + .vdso_code_start = compat_vdso_start,
> > + .vdso_code_end = compat_vdso_end,
> > + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> > + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> > + },
> > +#endif
> > };
> > +
> > +static void __init __vdso_init(enum vdso_abi abi)
> > +{
> > + unsigned int i;
> > + struct page **vdso_pagelist;
> > + unsigned long pfn;
> > +
> > + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
> > + panic("vDSO is not a valid ELF object!\n");
> > +
> > + vdso_info[abi].vdso_pages = (
> > + vdso_info[abi].vdso_code_end -
> > + vdso_info[abi].vdso_code_start) >>
> > + PAGE_SHIFT;
> > +
> > + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
> > + sizeof(struct page *),
> > + GFP_KERNEL);
> > + if (vdso_pagelist == NULL)
> > + panic("vDSO kcalloc failed!\n");
> > +
> > + /* Grab the vDSO code pages. */
> > + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
> > +
> > + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
> > + vdso_pagelist[i] = pfn_to_page(pfn + i);
> > +
> > + vdso_info[abi].cm->pages = vdso_pagelist;
> > +}
> > +
> > +#ifdef CONFIG_TIME_NS
> > +struct vdso_data *arch_get_vdso_data(void *vvar_page)
> > +{
> > + return (struct vdso_data *)(vvar_page);
> > +}
> > +
> > +/*
> > + * The vvar mapping contains data for a specific time namespace, so when a task
> > + * changes namespace we must unmap its vvar data for the old namespace.
> > + * Subsequent faults will map in data for the new namespace.
> > + *
> > + * For more details see timens_setup_vdso_data().
> > + */
> > +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> > +{
> > + struct mm_struct *mm = task->mm;
> > + struct vm_area_struct *vma;
> > +
> > + mmap_read_lock(mm);
> > +
> > + for (vma = mm->mmap; vma; vma = vma->vm_next) {
> > + unsigned long size = vma->vm_end - vma->vm_start;
> > +
> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
> > + zap_page_range(vma, vma->vm_start, size);
> > +#ifdef CONFIG_COMPAT
> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
> > + zap_page_range(vma, vma->vm_start, size);
> > +#endif
> > + }
> > +
> > + mmap_read_unlock(mm);
> > + return 0;
> > +}
> > #endif
> >
> > static int __init vdso_init(void)
> > {
> > - __vdso_init(&vdso_info);
> > + __vdso_init(VDSO_ABI_RV64);
> > #ifdef CONFIG_COMPAT
> > - __vdso_init(&compat_vdso_info);
> > + __vdso_init(VDSO_ABI_RV32);
> > #endif
> >
> > return 0;
> > @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
> > static int __setup_additional_pages(struct mm_struct *mm,
> > struct linux_binprm *bprm,
> > int uses_interp,
> > - struct __vdso_info *vdso_info)
> > + enum vdso_abi abi)
> > {
> > unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
> > void *ret;
> >
> > BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
> >
> > - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
> > + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
> > /* Be sure to map the data page */
> > vdso_mapping_len = vdso_text_len + VVAR_SIZE;
> >
> > @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
> > }
> >
> > ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
> > - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
> > + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
> > if (IS_ERR(ret))
> > goto up_fail;
> >
> > vdso_base += VVAR_SIZE;
> > mm->context.vdso = (void *)vdso_base;
> > - mm->context.vdso_info = (void *)vdso_info;
> >
> > ret =
> > _install_special_mapping(mm, vdso_base, vdso_text_len,
> > (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
> > - vdso_info->cm);
> > + vdso_info[abi].cm);
> >
> > if (IS_ERR(ret))
> > goto up_fail;
> > @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> > if (mmap_write_lock_killable(mm))
> > return -EINTR;
> >
> > - ret = __setup_additional_pages(mm, bprm, uses_interp,
> > - &compat_vdso_info);
> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
> > mmap_write_unlock(mm);
> >
> > return ret;
> > @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
> > if (mmap_write_lock_killable(mm))
> > return -EINTR;
> >
> > - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
> > mmap_write_unlock(mm);
> >
> > return ret;
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
@ 2022-09-22 12:07 ` Jisheng Zhang
0 siblings, 0 replies; 10+ messages in thread
From: Jisheng Zhang @ 2022-09-22 12:07 UTC (permalink / raw)
To: Palmer Dabbelt; +Cc: Paul Walmsley, aou, guoren, linux-riscv, linux-kernel
On Thu, Sep 15, 2022 at 11:02:19AM -0700, Palmer Dabbelt wrote:
> On Thu, 08 Sep 2022 08:04:21 PDT (-0700), jszhang@kernel.org wrote:
> > Testing tools/testing/selftests/timens/vfork_exec.c got below
> > kernel log:
> >
> > [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
> > [ 6.842255] Oops [#1]
> > [ 6.842871] Modules linked in:
> > [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
> > [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
> > [ 6.848009] epc : vdso_join_timens+0xd2/0x110
> > [ 6.850097] ra : vdso_join_timens+0xd2/0x110
> > [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
> > [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
> > [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
> > [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
> > [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
> > [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
> > [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
> > [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
> > [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
> > [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
> > [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
> > [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
> > [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
> > [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
> > [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
> > [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
> > [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
> > [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
> > [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
> > [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
> > [ 6.877484] ---[ end trace 0000000000000000 ]---
> >
> > This is because the mm->context.vdso_info is NULL in vfork case. From
> > another side, mm->context.vdso_info either points to vdso info
> > for RV64 or vdso info for compat, there's no need to bloat riscv's
> > mm_context_t, we can handle the difference when setup the additional
> > page for vdso.
>
> Makes sense, but I think there's a lot more diff here than we need in order
The reason of "a lot more diff" is moving the code to avoid forward declaration.
If you prefer smaller fix, I can provide a simpler one w/ forware
declaration. And provide a new clean up patch for next window, what do you
think?
Thanks
> to just fix the bug. Does something like the following still fix it? Also
> at kernel.org/palmer/vdso-fix-v3 . Maybe it's a bit pedantic , but this
> late in the cycle with everyone traveling I'd prefer to keep the fixes
> smaller when possible.
>
> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> index cedcf8ea3c76..0099dc116168 100644
> --- a/arch/riscv/include/asm/mmu.h
> +++ b/arch/riscv/include/asm/mmu.h
> @@ -16,7 +16,6 @@ typedef struct {
> atomic_long_t id;
> #endif
> void *vdso;
> - void *vdso_info;
> #ifdef CONFIG_SMP
> /* A local icache flush is needed before user execution can resume. */
> cpumask_t icache_stale_mask;
> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> index 69b05b6c181b..58b8d73a4b1f 100644
> --- a/arch/riscv/kernel/vdso.c
> +++ b/arch/riscv/kernel/vdso.c
> @@ -23,8 +23,10 @@ struct vdso_data {
> #endif
>
> extern char vdso_start[], vdso_end[];
> +static struct __vdso_info vdso_info;
> #ifdef CONFIG_COMPAT
> extern char compat_vdso_start[], compat_vdso_end[];
> +static struct __vdso_info compat_vdso_info;
> #endif
>
> enum vvar_pages {
> @@ -114,15 +116,18 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> {
> struct mm_struct *mm = task->mm;
> struct vm_area_struct *vma;
> - struct __vdso_info *vdso_info = mm->context.vdso_info;
>
> mmap_read_lock(mm);
>
> for (vma = mm->mmap; vma; vma = vma->vm_next) {
> unsigned long size = vma->vm_end - vma->vm_start;
>
> - if (vma_is_special_mapping(vma, vdso_info->dm))
> + if (vma_is_special_mapping(vma, vdso_info.dm))
> zap_page_range(vma, vma->vm_start, size);
> +#ifdef CONFIG_COMPAT
> + if (vma_is_special_mapping(vma, compat_vdso_info.dm))
> + zap_page_range(vma, vma->vm_start, size);
> +#endif
> }
>
> mmap_read_unlock(mm);
> @@ -264,7 +269,6 @@ static int __setup_additional_pages(struct mm_struct *mm,
>
> vdso_base += VVAR_SIZE;
> mm->context.vdso = (void *)vdso_base;
> - mm->context.vdso_info = (void *)vdso_info;
>
> ret =
> _install_special_mapping(mm, vdso_base, vdso_text_len,
>
> >
> > Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> > Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
> > ---
> >
> > since v1:
> > - add "Fixes" tag
> > - fix build error when CONFIG_COMPAT is enabled.
> >
> > arch/riscv/include/asm/mmu.h | 1 -
> > arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
> > 2 files changed, 95 insertions(+), 84 deletions(-)
> >
> > diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
> > index cedcf8ea3c76..0099dc116168 100644
> > --- a/arch/riscv/include/asm/mmu.h
> > +++ b/arch/riscv/include/asm/mmu.h
> > @@ -16,7 +16,6 @@ typedef struct {
> > atomic_long_t id;
> > #endif
> > void *vdso;
> > - void *vdso_info;
> > #ifdef CONFIG_SMP
> > /* A local icache flush is needed before user execution can resume. */
> > cpumask_t icache_stale_mask;
> > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
> > index 69b05b6c181b..8ca3b821e1b5 100644
> > --- a/arch/riscv/kernel/vdso.c
> > +++ b/arch/riscv/kernel/vdso.c
> > @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
> > extern char compat_vdso_start[], compat_vdso_end[];
> > #endif
> >
> > +enum vdso_abi {
> > + VDSO_ABI_RV64,
> > + VDSO_ABI_RV32,
> > +};
> > +
> > enum vvar_pages {
> > VVAR_DATA_PAGE_OFFSET,
> > VVAR_TIMENS_PAGE_OFFSET,
> > @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
> > return 0;
> > }
> >
> > -static void __init __vdso_init(struct __vdso_info *vdso_info)
> > -{
> > - unsigned int i;
> > - struct page **vdso_pagelist;
> > - unsigned long pfn;
> > -
> > - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
> > - panic("vDSO is not a valid ELF object!\n");
> > -
> > - vdso_info->vdso_pages = (
> > - vdso_info->vdso_code_end -
> > - vdso_info->vdso_code_start) >>
> > - PAGE_SHIFT;
> > -
> > - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
> > - sizeof(struct page *),
> > - GFP_KERNEL);
> > - if (vdso_pagelist == NULL)
> > - panic("vDSO kcalloc failed!\n");
> > -
> > - /* Grab the vDSO code pages. */
> > - pfn = sym_to_pfn(vdso_info->vdso_code_start);
> > -
> > - for (i = 0; i < vdso_info->vdso_pages; i++)
> > - vdso_pagelist[i] = pfn_to_page(pfn + i);
> > -
> > - vdso_info->cm->pages = vdso_pagelist;
> > -}
> > -
> > #ifdef CONFIG_TIME_NS
> > -struct vdso_data *arch_get_vdso_data(void *vvar_page)
> > -{
> > - return (struct vdso_data *)(vvar_page);
> > -}
> > -
> > -/*
> > - * The vvar mapping contains data for a specific time namespace, so when a task
> > - * changes namespace we must unmap its vvar data for the old namespace.
> > - * Subsequent faults will map in data for the new namespace.
> > - *
> > - * For more details see timens_setup_vdso_data().
> > - */
> > -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> > -{
> > - struct mm_struct *mm = task->mm;
> > - struct vm_area_struct *vma;
> > - struct __vdso_info *vdso_info = mm->context.vdso_info;
> > -
> > - mmap_read_lock(mm);
> > -
> > - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> > - unsigned long size = vma->vm_end - vma->vm_start;
> > -
> > - if (vma_is_special_mapping(vma, vdso_info->dm))
> > - zap_page_range(vma, vma->vm_start, size);
> > - }
> > -
> > - mmap_read_unlock(mm);
> > - return 0;
> > -}
> > -
> > static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
> > {
> > if (likely(vma->vm_mm == current->mm))
> > @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
> > },
> > };
> >
> > -static struct __vdso_info vdso_info __ro_after_init = {
> > - .name = "vdso",
> > - .vdso_code_start = vdso_start,
> > - .vdso_code_end = vdso_end,
> > - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> > - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> > -};
> >
> > #ifdef CONFIG_COMPAT
> > static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> > @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
> > .mremap = vdso_mremap,
> > },
> > };
> > +#endif
> >
> > -static struct __vdso_info compat_vdso_info __ro_after_init = {
> > - .name = "compat_vdso",
> > - .vdso_code_start = compat_vdso_start,
> > - .vdso_code_end = compat_vdso_end,
> > - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> > - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> > +static struct __vdso_info vdso_info[] __ro_after_init = {
> > + [VDSO_ABI_RV64] = {
> > + .name = "vdso",
> > + .vdso_code_start = vdso_start,
> > + .vdso_code_end = vdso_end,
> > + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
> > + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
> > + },
> > +#ifdef CONFIG_COMPAT
> > + [VDSO_ABI_RV32] = {
> > + .name = "compat_vdso",
> > + .vdso_code_start = compat_vdso_start,
> > + .vdso_code_end = compat_vdso_end,
> > + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
> > + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
> > + },
> > +#endif
> > };
> > +
> > +static void __init __vdso_init(enum vdso_abi abi)
> > +{
> > + unsigned int i;
> > + struct page **vdso_pagelist;
> > + unsigned long pfn;
> > +
> > + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
> > + panic("vDSO is not a valid ELF object!\n");
> > +
> > + vdso_info[abi].vdso_pages = (
> > + vdso_info[abi].vdso_code_end -
> > + vdso_info[abi].vdso_code_start) >>
> > + PAGE_SHIFT;
> > +
> > + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
> > + sizeof(struct page *),
> > + GFP_KERNEL);
> > + if (vdso_pagelist == NULL)
> > + panic("vDSO kcalloc failed!\n");
> > +
> > + /* Grab the vDSO code pages. */
> > + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
> > +
> > + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
> > + vdso_pagelist[i] = pfn_to_page(pfn + i);
> > +
> > + vdso_info[abi].cm->pages = vdso_pagelist;
> > +}
> > +
> > +#ifdef CONFIG_TIME_NS
> > +struct vdso_data *arch_get_vdso_data(void *vvar_page)
> > +{
> > + return (struct vdso_data *)(vvar_page);
> > +}
> > +
> > +/*
> > + * The vvar mapping contains data for a specific time namespace, so when a task
> > + * changes namespace we must unmap its vvar data for the old namespace.
> > + * Subsequent faults will map in data for the new namespace.
> > + *
> > + * For more details see timens_setup_vdso_data().
> > + */
> > +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> > +{
> > + struct mm_struct *mm = task->mm;
> > + struct vm_area_struct *vma;
> > +
> > + mmap_read_lock(mm);
> > +
> > + for (vma = mm->mmap; vma; vma = vma->vm_next) {
> > + unsigned long size = vma->vm_end - vma->vm_start;
> > +
> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
> > + zap_page_range(vma, vma->vm_start, size);
> > +#ifdef CONFIG_COMPAT
> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
> > + zap_page_range(vma, vma->vm_start, size);
> > +#endif
> > + }
> > +
> > + mmap_read_unlock(mm);
> > + return 0;
> > +}
> > #endif
> >
> > static int __init vdso_init(void)
> > {
> > - __vdso_init(&vdso_info);
> > + __vdso_init(VDSO_ABI_RV64);
> > #ifdef CONFIG_COMPAT
> > - __vdso_init(&compat_vdso_info);
> > + __vdso_init(VDSO_ABI_RV32);
> > #endif
> >
> > return 0;
> > @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
> > static int __setup_additional_pages(struct mm_struct *mm,
> > struct linux_binprm *bprm,
> > int uses_interp,
> > - struct __vdso_info *vdso_info)
> > + enum vdso_abi abi)
> > {
> > unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
> > void *ret;
> >
> > BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
> >
> > - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
> > + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
> > /* Be sure to map the data page */
> > vdso_mapping_len = vdso_text_len + VVAR_SIZE;
> >
> > @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
> > }
> >
> > ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
> > - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
> > + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
> > if (IS_ERR(ret))
> > goto up_fail;
> >
> > vdso_base += VVAR_SIZE;
> > mm->context.vdso = (void *)vdso_base;
> > - mm->context.vdso_info = (void *)vdso_info;
> >
> > ret =
> > _install_special_mapping(mm, vdso_base, vdso_text_len,
> > (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
> > - vdso_info->cm);
> > + vdso_info[abi].cm);
> >
> > if (IS_ERR(ret))
> > goto up_fail;
> > @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
> > if (mmap_write_lock_killable(mm))
> > return -EINTR;
> >
> > - ret = __setup_additional_pages(mm, bprm, uses_interp,
> > - &compat_vdso_info);
> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
> > mmap_write_unlock(mm);
> >
> > return ret;
> > @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
> > if (mmap_write_lock_killable(mm))
> > return -EINTR;
> >
> > - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
> > mmap_write_unlock(mm);
> >
> > return ret;
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
2022-09-22 12:07 ` Jisheng Zhang
@ 2022-09-22 16:38 ` Palmer Dabbelt
-1 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2022-09-22 16:38 UTC (permalink / raw)
To: jszhang; +Cc: Paul Walmsley, aou, guoren, linux-riscv, linux-kernel
On Thu, 22 Sep 2022 05:07:44 PDT (-0700), jszhang@kernel.org wrote:
> On Thu, Sep 15, 2022 at 11:02:19AM -0700, Palmer Dabbelt wrote:
>> On Thu, 08 Sep 2022 08:04:21 PDT (-0700), jszhang@kernel.org wrote:
>> > Testing tools/testing/selftests/timens/vfork_exec.c got below
>> > kernel log:
>> >
>> > [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
>> > [ 6.842255] Oops [#1]
>> > [ 6.842871] Modules linked in:
>> > [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
>> > [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
>> > [ 6.848009] epc : vdso_join_timens+0xd2/0x110
>> > [ 6.850097] ra : vdso_join_timens+0xd2/0x110
>> > [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
>> > [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
>> > [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
>> > [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
>> > [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
>> > [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
>> > [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
>> > [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
>> > [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
>> > [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
>> > [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
>> > [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
>> > [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
>> > [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
>> > [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
>> > [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
>> > [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
>> > [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
>> > [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
>> > [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
>> > [ 6.877484] ---[ end trace 0000000000000000 ]---
>> >
>> > This is because the mm->context.vdso_info is NULL in vfork case. From
>> > another side, mm->context.vdso_info either points to vdso info
>> > for RV64 or vdso info for compat, there's no need to bloat riscv's
>> > mm_context_t, we can handle the difference when setup the additional
>> > page for vdso.
>>
>> Makes sense, but I think there's a lot more diff here than we need in order
>
> The reason of "a lot more diff" is moving the code to avoid forward declaration.
> If you prefer smaller fix, I can provide a simpler one w/ forware
> declaration. And provide a new clean up patch for next window, what do you
> think?
Works for me. If you put the two back-to-back on 6.0-rc1 then I can
avoid the merge conflict. Thanks!
>
> Thanks
>> to just fix the bug. Does something like the following still fix it? Also
>> at kernel.org/palmer/vdso-fix-v3 . Maybe it's a bit pedantic , but this
>> late in the cycle with everyone traveling I'd prefer to keep the fixes
>> smaller when possible.
>>
>> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
>> index cedcf8ea3c76..0099dc116168 100644
>> --- a/arch/riscv/include/asm/mmu.h
>> +++ b/arch/riscv/include/asm/mmu.h
>> @@ -16,7 +16,6 @@ typedef struct {
>> atomic_long_t id;
>> #endif
>> void *vdso;
>> - void *vdso_info;
>> #ifdef CONFIG_SMP
>> /* A local icache flush is needed before user execution can resume. */
>> cpumask_t icache_stale_mask;
>> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
>> index 69b05b6c181b..58b8d73a4b1f 100644
>> --- a/arch/riscv/kernel/vdso.c
>> +++ b/arch/riscv/kernel/vdso.c
>> @@ -23,8 +23,10 @@ struct vdso_data {
>> #endif
>>
>> extern char vdso_start[], vdso_end[];
>> +static struct __vdso_info vdso_info;
>> #ifdef CONFIG_COMPAT
>> extern char compat_vdso_start[], compat_vdso_end[];
>> +static struct __vdso_info compat_vdso_info;
>> #endif
>>
>> enum vvar_pages {
>> @@ -114,15 +116,18 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
>> {
>> struct mm_struct *mm = task->mm;
>> struct vm_area_struct *vma;
>> - struct __vdso_info *vdso_info = mm->context.vdso_info;
>>
>> mmap_read_lock(mm);
>>
>> for (vma = mm->mmap; vma; vma = vma->vm_next) {
>> unsigned long size = vma->vm_end - vma->vm_start;
>>
>> - if (vma_is_special_mapping(vma, vdso_info->dm))
>> + if (vma_is_special_mapping(vma, vdso_info.dm))
>> zap_page_range(vma, vma->vm_start, size);
>> +#ifdef CONFIG_COMPAT
>> + if (vma_is_special_mapping(vma, compat_vdso_info.dm))
>> + zap_page_range(vma, vma->vm_start, size);
>> +#endif
>> }
>>
>> mmap_read_unlock(mm);
>> @@ -264,7 +269,6 @@ static int __setup_additional_pages(struct mm_struct *mm,
>>
>> vdso_base += VVAR_SIZE;
>> mm->context.vdso = (void *)vdso_base;
>> - mm->context.vdso_info = (void *)vdso_info;
>>
>> ret =
>> _install_special_mapping(mm, vdso_base, vdso_text_len,
>>
>> >
>> > Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
>> > Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
>> > ---
>> >
>> > since v1:
>> > - add "Fixes" tag
>> > - fix build error when CONFIG_COMPAT is enabled.
>> >
>> > arch/riscv/include/asm/mmu.h | 1 -
>> > arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
>> > 2 files changed, 95 insertions(+), 84 deletions(-)
>> >
>> > diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
>> > index cedcf8ea3c76..0099dc116168 100644
>> > --- a/arch/riscv/include/asm/mmu.h
>> > +++ b/arch/riscv/include/asm/mmu.h
>> > @@ -16,7 +16,6 @@ typedef struct {
>> > atomic_long_t id;
>> > #endif
>> > void *vdso;
>> > - void *vdso_info;
>> > #ifdef CONFIG_SMP
>> > /* A local icache flush is needed before user execution can resume. */
>> > cpumask_t icache_stale_mask;
>> > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
>> > index 69b05b6c181b..8ca3b821e1b5 100644
>> > --- a/arch/riscv/kernel/vdso.c
>> > +++ b/arch/riscv/kernel/vdso.c
>> > @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
>> > extern char compat_vdso_start[], compat_vdso_end[];
>> > #endif
>> >
>> > +enum vdso_abi {
>> > + VDSO_ABI_RV64,
>> > + VDSO_ABI_RV32,
>> > +};
>> > +
>> > enum vvar_pages {
>> > VVAR_DATA_PAGE_OFFSET,
>> > VVAR_TIMENS_PAGE_OFFSET,
>> > @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
>> > return 0;
>> > }
>> >
>> > -static void __init __vdso_init(struct __vdso_info *vdso_info)
>> > -{
>> > - unsigned int i;
>> > - struct page **vdso_pagelist;
>> > - unsigned long pfn;
>> > -
>> > - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
>> > - panic("vDSO is not a valid ELF object!\n");
>> > -
>> > - vdso_info->vdso_pages = (
>> > - vdso_info->vdso_code_end -
>> > - vdso_info->vdso_code_start) >>
>> > - PAGE_SHIFT;
>> > -
>> > - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
>> > - sizeof(struct page *),
>> > - GFP_KERNEL);
>> > - if (vdso_pagelist == NULL)
>> > - panic("vDSO kcalloc failed!\n");
>> > -
>> > - /* Grab the vDSO code pages. */
>> > - pfn = sym_to_pfn(vdso_info->vdso_code_start);
>> > -
>> > - for (i = 0; i < vdso_info->vdso_pages; i++)
>> > - vdso_pagelist[i] = pfn_to_page(pfn + i);
>> > -
>> > - vdso_info->cm->pages = vdso_pagelist;
>> > -}
>> > -
>> > #ifdef CONFIG_TIME_NS
>> > -struct vdso_data *arch_get_vdso_data(void *vvar_page)
>> > -{
>> > - return (struct vdso_data *)(vvar_page);
>> > -}
>> > -
>> > -/*
>> > - * The vvar mapping contains data for a specific time namespace, so when a task
>> > - * changes namespace we must unmap its vvar data for the old namespace.
>> > - * Subsequent faults will map in data for the new namespace.
>> > - *
>> > - * For more details see timens_setup_vdso_data().
>> > - */
>> > -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
>> > -{
>> > - struct mm_struct *mm = task->mm;
>> > - struct vm_area_struct *vma;
>> > - struct __vdso_info *vdso_info = mm->context.vdso_info;
>> > -
>> > - mmap_read_lock(mm);
>> > -
>> > - for (vma = mm->mmap; vma; vma = vma->vm_next) {
>> > - unsigned long size = vma->vm_end - vma->vm_start;
>> > -
>> > - if (vma_is_special_mapping(vma, vdso_info->dm))
>> > - zap_page_range(vma, vma->vm_start, size);
>> > - }
>> > -
>> > - mmap_read_unlock(mm);
>> > - return 0;
>> > -}
>> > -
>> > static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
>> > {
>> > if (likely(vma->vm_mm == current->mm))
>> > @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
>> > },
>> > };
>> >
>> > -static struct __vdso_info vdso_info __ro_after_init = {
>> > - .name = "vdso",
>> > - .vdso_code_start = vdso_start,
>> > - .vdso_code_end = vdso_end,
>> > - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
>> > - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
>> > -};
>> >
>> > #ifdef CONFIG_COMPAT
>> > static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
>> > @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
>> > .mremap = vdso_mremap,
>> > },
>> > };
>> > +#endif
>> >
>> > -static struct __vdso_info compat_vdso_info __ro_after_init = {
>> > - .name = "compat_vdso",
>> > - .vdso_code_start = compat_vdso_start,
>> > - .vdso_code_end = compat_vdso_end,
>> > - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
>> > - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
>> > +static struct __vdso_info vdso_info[] __ro_after_init = {
>> > + [VDSO_ABI_RV64] = {
>> > + .name = "vdso",
>> > + .vdso_code_start = vdso_start,
>> > + .vdso_code_end = vdso_end,
>> > + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
>> > + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
>> > + },
>> > +#ifdef CONFIG_COMPAT
>> > + [VDSO_ABI_RV32] = {
>> > + .name = "compat_vdso",
>> > + .vdso_code_start = compat_vdso_start,
>> > + .vdso_code_end = compat_vdso_end,
>> > + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
>> > + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
>> > + },
>> > +#endif
>> > };
>> > +
>> > +static void __init __vdso_init(enum vdso_abi abi)
>> > +{
>> > + unsigned int i;
>> > + struct page **vdso_pagelist;
>> > + unsigned long pfn;
>> > +
>> > + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
>> > + panic("vDSO is not a valid ELF object!\n");
>> > +
>> > + vdso_info[abi].vdso_pages = (
>> > + vdso_info[abi].vdso_code_end -
>> > + vdso_info[abi].vdso_code_start) >>
>> > + PAGE_SHIFT;
>> > +
>> > + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
>> > + sizeof(struct page *),
>> > + GFP_KERNEL);
>> > + if (vdso_pagelist == NULL)
>> > + panic("vDSO kcalloc failed!\n");
>> > +
>> > + /* Grab the vDSO code pages. */
>> > + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
>> > +
>> > + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
>> > + vdso_pagelist[i] = pfn_to_page(pfn + i);
>> > +
>> > + vdso_info[abi].cm->pages = vdso_pagelist;
>> > +}
>> > +
>> > +#ifdef CONFIG_TIME_NS
>> > +struct vdso_data *arch_get_vdso_data(void *vvar_page)
>> > +{
>> > + return (struct vdso_data *)(vvar_page);
>> > +}
>> > +
>> > +/*
>> > + * The vvar mapping contains data for a specific time namespace, so when a task
>> > + * changes namespace we must unmap its vvar data for the old namespace.
>> > + * Subsequent faults will map in data for the new namespace.
>> > + *
>> > + * For more details see timens_setup_vdso_data().
>> > + */
>> > +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
>> > +{
>> > + struct mm_struct *mm = task->mm;
>> > + struct vm_area_struct *vma;
>> > +
>> > + mmap_read_lock(mm);
>> > +
>> > + for (vma = mm->mmap; vma; vma = vma->vm_next) {
>> > + unsigned long size = vma->vm_end - vma->vm_start;
>> > +
>> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
>> > + zap_page_range(vma, vma->vm_start, size);
>> > +#ifdef CONFIG_COMPAT
>> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
>> > + zap_page_range(vma, vma->vm_start, size);
>> > +#endif
>> > + }
>> > +
>> > + mmap_read_unlock(mm);
>> > + return 0;
>> > +}
>> > #endif
>> >
>> > static int __init vdso_init(void)
>> > {
>> > - __vdso_init(&vdso_info);
>> > + __vdso_init(VDSO_ABI_RV64);
>> > #ifdef CONFIG_COMPAT
>> > - __vdso_init(&compat_vdso_info);
>> > + __vdso_init(VDSO_ABI_RV32);
>> > #endif
>> >
>> > return 0;
>> > @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
>> > static int __setup_additional_pages(struct mm_struct *mm,
>> > struct linux_binprm *bprm,
>> > int uses_interp,
>> > - struct __vdso_info *vdso_info)
>> > + enum vdso_abi abi)
>> > {
>> > unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
>> > void *ret;
>> >
>> > BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
>> >
>> > - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
>> > + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
>> > /* Be sure to map the data page */
>> > vdso_mapping_len = vdso_text_len + VVAR_SIZE;
>> >
>> > @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
>> > }
>> >
>> > ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
>> > - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
>> > + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
>> > if (IS_ERR(ret))
>> > goto up_fail;
>> >
>> > vdso_base += VVAR_SIZE;
>> > mm->context.vdso = (void *)vdso_base;
>> > - mm->context.vdso_info = (void *)vdso_info;
>> >
>> > ret =
>> > _install_special_mapping(mm, vdso_base, vdso_text_len,
>> > (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
>> > - vdso_info->cm);
>> > + vdso_info[abi].cm);
>> >
>> > if (IS_ERR(ret))
>> > goto up_fail;
>> > @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
>> > if (mmap_write_lock_killable(mm))
>> > return -EINTR;
>> >
>> > - ret = __setup_additional_pages(mm, bprm, uses_interp,
>> > - &compat_vdso_info);
>> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
>> > mmap_write_unlock(mm);
>> >
>> > return ret;
>> > @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
>> > if (mmap_write_lock_killable(mm))
>> > return -EINTR;
>> >
>> > - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
>> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
>> > mmap_write_unlock(mm);
>> >
>> > return ret;
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
@ 2022-09-22 16:38 ` Palmer Dabbelt
0 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2022-09-22 16:38 UTC (permalink / raw)
To: jszhang; +Cc: Paul Walmsley, aou, guoren, linux-riscv, linux-kernel
On Thu, 22 Sep 2022 05:07:44 PDT (-0700), jszhang@kernel.org wrote:
> On Thu, Sep 15, 2022 at 11:02:19AM -0700, Palmer Dabbelt wrote:
>> On Thu, 08 Sep 2022 08:04:21 PDT (-0700), jszhang@kernel.org wrote:
>> > Testing tools/testing/selftests/timens/vfork_exec.c got below
>> > kernel log:
>> >
>> > [ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
>> > [ 6.842255] Oops [#1]
>> > [ 6.842871] Modules linked in:
>> > [ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
>> > [ 6.845861] Hardware name: riscv-virtio,qemu (DT)
>> > [ 6.848009] epc : vdso_join_timens+0xd2/0x110
>> > [ 6.850097] ra : vdso_join_timens+0xd2/0x110
>> > [ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
>> > [ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
>> > [ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
>> > [ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
>> > [ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
>> > [ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
>> > [ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
>> > [ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
>> > [ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
>> > [ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
>> > [ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
>> > [ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
>> > [ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
>> > [ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
>> > [ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
>> > [ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
>> > [ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
>> > [ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
>> > [ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
>> > [ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
>> > [ 6.877484] ---[ end trace 0000000000000000 ]---
>> >
>> > This is because the mm->context.vdso_info is NULL in vfork case. From
>> > another side, mm->context.vdso_info either points to vdso info
>> > for RV64 or vdso info for compat, there's no need to bloat riscv's
>> > mm_context_t, we can handle the difference when setup the additional
>> > page for vdso.
>>
>> Makes sense, but I think there's a lot more diff here than we need in order
>
> The reason of "a lot more diff" is moving the code to avoid forward declaration.
> If you prefer smaller fix, I can provide a simpler one w/ forware
> declaration. And provide a new clean up patch for next window, what do you
> think?
Works for me. If you put the two back-to-back on 6.0-rc1 then I can
avoid the merge conflict. Thanks!
>
> Thanks
>> to just fix the bug. Does something like the following still fix it? Also
>> at kernel.org/palmer/vdso-fix-v3 . Maybe it's a bit pedantic , but this
>> late in the cycle with everyone traveling I'd prefer to keep the fixes
>> smaller when possible.
>>
>> diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
>> index cedcf8ea3c76..0099dc116168 100644
>> --- a/arch/riscv/include/asm/mmu.h
>> +++ b/arch/riscv/include/asm/mmu.h
>> @@ -16,7 +16,6 @@ typedef struct {
>> atomic_long_t id;
>> #endif
>> void *vdso;
>> - void *vdso_info;
>> #ifdef CONFIG_SMP
>> /* A local icache flush is needed before user execution can resume. */
>> cpumask_t icache_stale_mask;
>> diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
>> index 69b05b6c181b..58b8d73a4b1f 100644
>> --- a/arch/riscv/kernel/vdso.c
>> +++ b/arch/riscv/kernel/vdso.c
>> @@ -23,8 +23,10 @@ struct vdso_data {
>> #endif
>>
>> extern char vdso_start[], vdso_end[];
>> +static struct __vdso_info vdso_info;
>> #ifdef CONFIG_COMPAT
>> extern char compat_vdso_start[], compat_vdso_end[];
>> +static struct __vdso_info compat_vdso_info;
>> #endif
>>
>> enum vvar_pages {
>> @@ -114,15 +116,18 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
>> {
>> struct mm_struct *mm = task->mm;
>> struct vm_area_struct *vma;
>> - struct __vdso_info *vdso_info = mm->context.vdso_info;
>>
>> mmap_read_lock(mm);
>>
>> for (vma = mm->mmap; vma; vma = vma->vm_next) {
>> unsigned long size = vma->vm_end - vma->vm_start;
>>
>> - if (vma_is_special_mapping(vma, vdso_info->dm))
>> + if (vma_is_special_mapping(vma, vdso_info.dm))
>> zap_page_range(vma, vma->vm_start, size);
>> +#ifdef CONFIG_COMPAT
>> + if (vma_is_special_mapping(vma, compat_vdso_info.dm))
>> + zap_page_range(vma, vma->vm_start, size);
>> +#endif
>> }
>>
>> mmap_read_unlock(mm);
>> @@ -264,7 +269,6 @@ static int __setup_additional_pages(struct mm_struct *mm,
>>
>> vdso_base += VVAR_SIZE;
>> mm->context.vdso = (void *)vdso_base;
>> - mm->context.vdso_info = (void *)vdso_info;
>>
>> ret =
>> _install_special_mapping(mm, vdso_base, vdso_text_len,
>>
>> >
>> > Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
>> > Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
>> > ---
>> >
>> > since v1:
>> > - add "Fixes" tag
>> > - fix build error when CONFIG_COMPAT is enabled.
>> >
>> > arch/riscv/include/asm/mmu.h | 1 -
>> > arch/riscv/kernel/vdso.c | 178 +++++++++++++++++++----------------
>> > 2 files changed, 95 insertions(+), 84 deletions(-)
>> >
>> > diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
>> > index cedcf8ea3c76..0099dc116168 100644
>> > --- a/arch/riscv/include/asm/mmu.h
>> > +++ b/arch/riscv/include/asm/mmu.h
>> > @@ -16,7 +16,6 @@ typedef struct {
>> > atomic_long_t id;
>> > #endif
>> > void *vdso;
>> > - void *vdso_info;
>> > #ifdef CONFIG_SMP
>> > /* A local icache flush is needed before user execution can resume. */
>> > cpumask_t icache_stale_mask;
>> > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
>> > index 69b05b6c181b..8ca3b821e1b5 100644
>> > --- a/arch/riscv/kernel/vdso.c
>> > +++ b/arch/riscv/kernel/vdso.c
>> > @@ -27,6 +27,11 @@ extern char vdso_start[], vdso_end[];
>> > extern char compat_vdso_start[], compat_vdso_end[];
>> > #endif
>> >
>> > +enum vdso_abi {
>> > + VDSO_ABI_RV64,
>> > + VDSO_ABI_RV32,
>> > +};
>> > +
>> > enum vvar_pages {
>> > VVAR_DATA_PAGE_OFFSET,
>> > VVAR_TIMENS_PAGE_OFFSET,
>> > @@ -68,67 +73,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
>> > return 0;
>> > }
>> >
>> > -static void __init __vdso_init(struct __vdso_info *vdso_info)
>> > -{
>> > - unsigned int i;
>> > - struct page **vdso_pagelist;
>> > - unsigned long pfn;
>> > -
>> > - if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
>> > - panic("vDSO is not a valid ELF object!\n");
>> > -
>> > - vdso_info->vdso_pages = (
>> > - vdso_info->vdso_code_end -
>> > - vdso_info->vdso_code_start) >>
>> > - PAGE_SHIFT;
>> > -
>> > - vdso_pagelist = kcalloc(vdso_info->vdso_pages,
>> > - sizeof(struct page *),
>> > - GFP_KERNEL);
>> > - if (vdso_pagelist == NULL)
>> > - panic("vDSO kcalloc failed!\n");
>> > -
>> > - /* Grab the vDSO code pages. */
>> > - pfn = sym_to_pfn(vdso_info->vdso_code_start);
>> > -
>> > - for (i = 0; i < vdso_info->vdso_pages; i++)
>> > - vdso_pagelist[i] = pfn_to_page(pfn + i);
>> > -
>> > - vdso_info->cm->pages = vdso_pagelist;
>> > -}
>> > -
>> > #ifdef CONFIG_TIME_NS
>> > -struct vdso_data *arch_get_vdso_data(void *vvar_page)
>> > -{
>> > - return (struct vdso_data *)(vvar_page);
>> > -}
>> > -
>> > -/*
>> > - * The vvar mapping contains data for a specific time namespace, so when a task
>> > - * changes namespace we must unmap its vvar data for the old namespace.
>> > - * Subsequent faults will map in data for the new namespace.
>> > - *
>> > - * For more details see timens_setup_vdso_data().
>> > - */
>> > -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
>> > -{
>> > - struct mm_struct *mm = task->mm;
>> > - struct vm_area_struct *vma;
>> > - struct __vdso_info *vdso_info = mm->context.vdso_info;
>> > -
>> > - mmap_read_lock(mm);
>> > -
>> > - for (vma = mm->mmap; vma; vma = vma->vm_next) {
>> > - unsigned long size = vma->vm_end - vma->vm_start;
>> > -
>> > - if (vma_is_special_mapping(vma, vdso_info->dm))
>> > - zap_page_range(vma, vma->vm_start, size);
>> > - }
>> > -
>> > - mmap_read_unlock(mm);
>> > - return 0;
>> > -}
>> > -
>> > static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
>> > {
>> > if (likely(vma->vm_mm == current->mm))
>> > @@ -197,13 +142,6 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
>> > },
>> > };
>> >
>> > -static struct __vdso_info vdso_info __ro_after_init = {
>> > - .name = "vdso",
>> > - .vdso_code_start = vdso_start,
>> > - .vdso_code_end = vdso_end,
>> > - .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
>> > - .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
>> > -};
>> >
>> > #ifdef CONFIG_COMPAT
>> > static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
>> > @@ -216,21 +154,97 @@ static struct vm_special_mapping rv_compat_vdso_maps[] __ro_after_init = {
>> > .mremap = vdso_mremap,
>> > },
>> > };
>> > +#endif
>> >
>> > -static struct __vdso_info compat_vdso_info __ro_after_init = {
>> > - .name = "compat_vdso",
>> > - .vdso_code_start = compat_vdso_start,
>> > - .vdso_code_end = compat_vdso_end,
>> > - .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
>> > - .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
>> > +static struct __vdso_info vdso_info[] __ro_after_init = {
>> > + [VDSO_ABI_RV64] = {
>> > + .name = "vdso",
>> > + .vdso_code_start = vdso_start,
>> > + .vdso_code_end = vdso_end,
>> > + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR],
>> > + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO],
>> > + },
>> > +#ifdef CONFIG_COMPAT
>> > + [VDSO_ABI_RV32] = {
>> > + .name = "compat_vdso",
>> > + .vdso_code_start = compat_vdso_start,
>> > + .vdso_code_end = compat_vdso_end,
>> > + .dm = &rv_compat_vdso_maps[RV_VDSO_MAP_VVAR],
>> > + .cm = &rv_compat_vdso_maps[RV_VDSO_MAP_VDSO],
>> > + },
>> > +#endif
>> > };
>> > +
>> > +static void __init __vdso_init(enum vdso_abi abi)
>> > +{
>> > + unsigned int i;
>> > + struct page **vdso_pagelist;
>> > + unsigned long pfn;
>> > +
>> > + if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4))
>> > + panic("vDSO is not a valid ELF object!\n");
>> > +
>> > + vdso_info[abi].vdso_pages = (
>> > + vdso_info[abi].vdso_code_end -
>> > + vdso_info[abi].vdso_code_start) >>
>> > + PAGE_SHIFT;
>> > +
>> > + vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
>> > + sizeof(struct page *),
>> > + GFP_KERNEL);
>> > + if (vdso_pagelist == NULL)
>> > + panic("vDSO kcalloc failed!\n");
>> > +
>> > + /* Grab the vDSO code pages. */
>> > + pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
>> > +
>> > + for (i = 0; i < vdso_info[abi].vdso_pages; i++)
>> > + vdso_pagelist[i] = pfn_to_page(pfn + i);
>> > +
>> > + vdso_info[abi].cm->pages = vdso_pagelist;
>> > +}
>> > +
>> > +#ifdef CONFIG_TIME_NS
>> > +struct vdso_data *arch_get_vdso_data(void *vvar_page)
>> > +{
>> > + return (struct vdso_data *)(vvar_page);
>> > +}
>> > +
>> > +/*
>> > + * The vvar mapping contains data for a specific time namespace, so when a task
>> > + * changes namespace we must unmap its vvar data for the old namespace.
>> > + * Subsequent faults will map in data for the new namespace.
>> > + *
>> > + * For more details see timens_setup_vdso_data().
>> > + */
>> > +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
>> > +{
>> > + struct mm_struct *mm = task->mm;
>> > + struct vm_area_struct *vma;
>> > +
>> > + mmap_read_lock(mm);
>> > +
>> > + for (vma = mm->mmap; vma; vma = vma->vm_next) {
>> > + unsigned long size = vma->vm_end - vma->vm_start;
>> > +
>> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV64].dm))
>> > + zap_page_range(vma, vma->vm_start, size);
>> > +#ifdef CONFIG_COMPAT
>> > + if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_RV32].dm))
>> > + zap_page_range(vma, vma->vm_start, size);
>> > +#endif
>> > + }
>> > +
>> > + mmap_read_unlock(mm);
>> > + return 0;
>> > +}
>> > #endif
>> >
>> > static int __init vdso_init(void)
>> > {
>> > - __vdso_init(&vdso_info);
>> > + __vdso_init(VDSO_ABI_RV64);
>> > #ifdef CONFIG_COMPAT
>> > - __vdso_init(&compat_vdso_info);
>> > + __vdso_init(VDSO_ABI_RV32);
>> > #endif
>> >
>> > return 0;
>> > @@ -240,14 +254,14 @@ arch_initcall(vdso_init);
>> > static int __setup_additional_pages(struct mm_struct *mm,
>> > struct linux_binprm *bprm,
>> > int uses_interp,
>> > - struct __vdso_info *vdso_info)
>> > + enum vdso_abi abi)
>> > {
>> > unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
>> > void *ret;
>> >
>> > BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
>> >
>> > - vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
>> > + vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
>> > /* Be sure to map the data page */
>> > vdso_mapping_len = vdso_text_len + VVAR_SIZE;
>> >
>> > @@ -258,18 +272,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
>> > }
>> >
>> > ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
>> > - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm);
>> > + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info[abi].dm);
>> > if (IS_ERR(ret))
>> > goto up_fail;
>> >
>> > vdso_base += VVAR_SIZE;
>> > mm->context.vdso = (void *)vdso_base;
>> > - mm->context.vdso_info = (void *)vdso_info;
>> >
>> > ret =
>> > _install_special_mapping(mm, vdso_base, vdso_text_len,
>> > (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
>> > - vdso_info->cm);
>> > + vdso_info[abi].cm);
>> >
>> > if (IS_ERR(ret))
>> > goto up_fail;
>> > @@ -291,8 +304,7 @@ int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
>> > if (mmap_write_lock_killable(mm))
>> > return -EINTR;
>> >
>> > - ret = __setup_additional_pages(mm, bprm, uses_interp,
>> > - &compat_vdso_info);
>> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV32);
>> > mmap_write_unlock(mm);
>> >
>> > return ret;
>> > @@ -307,7 +319,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
>> > if (mmap_write_lock_killable(mm))
>> > return -EINTR;
>> >
>> > - ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
>> > + ret = __setup_additional_pages(mm, bprm, uses_interp, VDSO_ABI_RV64);
>> > mmap_write_unlock(mm);
>> >
>> > return ret;
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2022-09-22 16:39 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-09-08 15:04 [PATCH v2] riscv: vdso: fix NULL deference in vdso_join_timens() when vfork Jisheng Zhang
2022-09-08 15:04 ` Jisheng Zhang
2022-09-09 3:48 ` Guo Ren
2022-09-09 3:48 ` Guo Ren
2022-09-15 18:02 ` Palmer Dabbelt
2022-09-15 18:02 ` Palmer Dabbelt
2022-09-22 12:07 ` Jisheng Zhang
2022-09-22 12:07 ` Jisheng Zhang
2022-09-22 16:38 ` Palmer Dabbelt
2022-09-22 16:38 ` Palmer Dabbelt
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.