From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
Alexander Sverdlin <alexander.sverdlin@nokia.com>,
Russell King <rmk+kernel@armlinux.org.uk>,
Florian Fainelli <f.fainelli@gmail.com>
Subject: [PATCH 5.10 08/63] ARM: 9079/1: ftrace: Add MODULE_PLTS support
Date: Fri, 24 Sep 2021 14:44:08 +0200 [thread overview]
Message-ID: <20210924124334.525793678@linuxfoundation.org> (raw)
In-Reply-To: <20210924124334.228235870@linuxfoundation.org>
From: Alex Sverdlin <alexander.sverdlin@nokia.com>
commit 79f32b221b18c15a98507b101ef4beb52444cc6f upstream
Teach ftrace_make_call() and ftrace_make_nop() about PLTs.
Teach PLT code about FTRACE and all its callbacks.
Otherwise the following might happen:
------------[ cut here ]------------
WARNING: CPU: 14 PID: 2265 at .../arch/arm/kernel/insn.c:14 __arm_gen_branch+0x83/0x8c()
...
Hardware name: LSI Axxia AXM55XX
[<c0314a49>] (unwind_backtrace) from [<c03115e9>] (show_stack+0x11/0x14)
[<c03115e9>] (show_stack) from [<c0519f51>] (dump_stack+0x81/0xa8)
[<c0519f51>] (dump_stack) from [<c032185d>] (warn_slowpath_common+0x69/0x90)
[<c032185d>] (warn_slowpath_common) from [<c03218f3>] (warn_slowpath_null+0x17/0x1c)
[<c03218f3>] (warn_slowpath_null) from [<c03143cf>] (__arm_gen_branch+0x83/0x8c)
[<c03143cf>] (__arm_gen_branch) from [<c0314337>] (ftrace_make_nop+0xf/0x24)
[<c0314337>] (ftrace_make_nop) from [<c038ebcb>] (ftrace_process_locs+0x27b/0x3e8)
[<c038ebcb>] (ftrace_process_locs) from [<c0378d79>] (load_module+0x11e9/0x1a44)
[<c0378d79>] (load_module) from [<c037974d>] (SyS_finit_module+0x59/0x84)
[<c037974d>] (SyS_finit_module) from [<c030e981>] (ret_fast_syscall+0x1/0x18)
---[ end trace e1b64ced7a89adcc ]---
------------[ cut here ]------------
WARNING: CPU: 14 PID: 2265 at .../kernel/trace/ftrace.c:1979 ftrace_bug+0x1b1/0x234()
...
Hardware name: LSI Axxia AXM55XX
[<c0314a49>] (unwind_backtrace) from [<c03115e9>] (show_stack+0x11/0x14)
[<c03115e9>] (show_stack) from [<c0519f51>] (dump_stack+0x81/0xa8)
[<c0519f51>] (dump_stack) from [<c032185d>] (warn_slowpath_common+0x69/0x90)
[<c032185d>] (warn_slowpath_common) from [<c03218f3>] (warn_slowpath_null+0x17/0x1c)
[<c03218f3>] (warn_slowpath_null) from [<c038e87d>] (ftrace_bug+0x1b1/0x234)
[<c038e87d>] (ftrace_bug) from [<c038ebd5>] (ftrace_process_locs+0x285/0x3e8)
[<c038ebd5>] (ftrace_process_locs) from [<c0378d79>] (load_module+0x11e9/0x1a44)
[<c0378d79>] (load_module) from [<c037974d>] (SyS_finit_module+0x59/0x84)
[<c037974d>] (SyS_finit_module) from [<c030e981>] (ret_fast_syscall+0x1/0x18)
---[ end trace e1b64ced7a89adcd ]---
ftrace failed to modify [<e9ef7006>] 0xe9ef7006
actual: 02:f0:3b:fa
ftrace record flags: 0
(0) expected tramp: c0314265
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm/include/asm/ftrace.h | 3 ++
arch/arm/include/asm/module.h | 1
arch/arm/kernel/ftrace.c | 46 ++++++++++++++++++++++++++++++++++--------
arch/arm/kernel/module-plts.c | 44 ++++++++++++++++++++++++++++++++++++----
4 files changed, 82 insertions(+), 12 deletions(-)
--- a/arch/arm/include/asm/ftrace.h
+++ b/arch/arm/include/asm/ftrace.h
@@ -15,6 +15,9 @@ extern void __gnu_mcount_nc(void);
#ifdef CONFIG_DYNAMIC_FTRACE
struct dyn_arch_ftrace {
+#ifdef CONFIG_ARM_MODULE_PLTS
+ struct module *mod;
+#endif
};
static inline unsigned long ftrace_call_adjust(unsigned long addr)
--- a/arch/arm/include/asm/module.h
+++ b/arch/arm/include/asm/module.h
@@ -30,6 +30,7 @@ struct plt_entries {
struct mod_plt_sec {
struct elf32_shdr *plt;
+ struct plt_entries *plt_ent;
int plt_count;
};
--- a/arch/arm/kernel/ftrace.c
+++ b/arch/arm/kernel/ftrace.c
@@ -68,9 +68,10 @@ int ftrace_arch_code_modify_post_process
return 0;
}
-static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
+static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr,
+ bool warn)
{
- return arm_gen_branch_link(pc, addr, true);
+ return arm_gen_branch_link(pc, addr, warn);
}
static int ftrace_modify_code(unsigned long pc, unsigned long old,
@@ -104,14 +105,14 @@ int ftrace_update_ftrace_func(ftrace_fun
int ret;
pc = (unsigned long)&ftrace_call;
- new = ftrace_call_replace(pc, (unsigned long)func);
+ new = ftrace_call_replace(pc, (unsigned long)func, true);
ret = ftrace_modify_code(pc, 0, new, false);
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
if (!ret) {
pc = (unsigned long)&ftrace_regs_call;
- new = ftrace_call_replace(pc, (unsigned long)func);
+ new = ftrace_call_replace(pc, (unsigned long)func, true);
ret = ftrace_modify_code(pc, 0, new, false);
}
@@ -124,10 +125,22 @@ int ftrace_make_call(struct dyn_ftrace *
{
unsigned long new, old;
unsigned long ip = rec->ip;
+ unsigned long aaddr = adjust_address(rec, addr);
+ struct module *mod = NULL;
+
+#ifdef CONFIG_ARM_MODULE_PLTS
+ mod = rec->arch.mod;
+#endif
old = ftrace_nop_replace(rec);
- new = ftrace_call_replace(ip, adjust_address(rec, addr));
+ new = ftrace_call_replace(ip, aaddr, !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+ if (!new && mod) {
+ aaddr = get_module_plt(mod, ip, aaddr);
+ new = ftrace_call_replace(ip, aaddr, true);
+ }
+#endif
return ftrace_modify_code(rec->ip, old, new, true);
}
@@ -140,9 +153,9 @@ int ftrace_modify_call(struct dyn_ftrace
unsigned long new, old;
unsigned long ip = rec->ip;
- old = ftrace_call_replace(ip, adjust_address(rec, old_addr));
+ old = ftrace_call_replace(ip, adjust_address(rec, old_addr), true);
- new = ftrace_call_replace(ip, adjust_address(rec, addr));
+ new = ftrace_call_replace(ip, adjust_address(rec, addr), true);
return ftrace_modify_code(rec->ip, old, new, true);
}
@@ -152,12 +165,29 @@ int ftrace_modify_call(struct dyn_ftrace
int ftrace_make_nop(struct module *mod,
struct dyn_ftrace *rec, unsigned long addr)
{
+ unsigned long aaddr = adjust_address(rec, addr);
unsigned long ip = rec->ip;
unsigned long old;
unsigned long new;
int ret;
- old = ftrace_call_replace(ip, adjust_address(rec, addr));
+#ifdef CONFIG_ARM_MODULE_PLTS
+ /* mod is only supplied during module loading */
+ if (!mod)
+ mod = rec->arch.mod;
+ else
+ rec->arch.mod = mod;
+#endif
+
+ old = ftrace_call_replace(ip, aaddr,
+ !IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+ if (!old && mod) {
+ aaddr = get_module_plt(mod, ip, aaddr);
+ old = ftrace_call_replace(ip, aaddr, true);
+ }
+#endif
+
new = ftrace_nop_replace(rec);
ret = ftrace_modify_code(ip, old, new, true);
--- a/arch/arm/kernel/module-plts.c
+++ b/arch/arm/kernel/module-plts.c
@@ -4,6 +4,7 @@
*/
#include <linux/elf.h>
+#include <linux/ftrace.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sort.h>
@@ -20,19 +21,52 @@
(PLT_ENT_STRIDE - 8))
#endif
+static const u32 fixed_plts[] = {
+#ifdef CONFIG_FUNCTION_TRACER
+ FTRACE_ADDR,
+ MCOUNT_ADDR,
+#endif
+};
+
static bool in_init(const struct module *mod, unsigned long loc)
{
return loc - (u32)mod->init_layout.base < mod->init_layout.size;
}
+static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt)
+{
+ int i;
+
+ if (!ARRAY_SIZE(fixed_plts) || pltsec->plt_count)
+ return;
+ pltsec->plt_count = ARRAY_SIZE(fixed_plts);
+
+ for (i = 0; i < ARRAY_SIZE(plt->ldr); ++i)
+ plt->ldr[i] = PLT_ENT_LDR;
+
+ BUILD_BUG_ON(sizeof(fixed_plts) > sizeof(plt->lit));
+ memcpy(plt->lit, fixed_plts, sizeof(fixed_plts));
+}
+
u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
{
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
&mod->arch.init;
+ struct plt_entries *plt;
+ int idx;
+
+ /* cache the address, ELF header is available only during module load */
+ if (!pltsec->plt_ent)
+ pltsec->plt_ent = (struct plt_entries *)pltsec->plt->sh_addr;
+ plt = pltsec->plt_ent;
- struct plt_entries *plt = (struct plt_entries *)pltsec->plt->sh_addr;
- int idx = 0;
+ prealloc_fixed(pltsec, plt);
+
+ for (idx = 0; idx < ARRAY_SIZE(fixed_plts); ++idx)
+ if (plt->lit[idx] == val)
+ return (u32)&plt->ldr[idx];
+ idx = 0;
/*
* Look for an existing entry pointing to 'val'. Given that the
* relocations are sorted, this will be the last entry we allocated.
@@ -180,8 +214,8 @@ static unsigned int count_plts(const Elf
int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
char *secstrings, struct module *mod)
{
- unsigned long core_plts = 0;
- unsigned long init_plts = 0;
+ unsigned long core_plts = ARRAY_SIZE(fixed_plts);
+ unsigned long init_plts = ARRAY_SIZE(fixed_plts);
Elf32_Shdr *s, *sechdrs_end = sechdrs + ehdr->e_shnum;
Elf32_Sym *syms = NULL;
@@ -236,6 +270,7 @@ int module_frob_arch_sections(Elf_Ehdr *
mod->arch.core.plt->sh_size = round_up(core_plts * PLT_ENT_SIZE,
sizeof(struct plt_entries));
mod->arch.core.plt_count = 0;
+ mod->arch.core.plt_ent = NULL;
mod->arch.init.plt->sh_type = SHT_NOBITS;
mod->arch.init.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
@@ -243,6 +278,7 @@ int module_frob_arch_sections(Elf_Ehdr *
mod->arch.init.plt->sh_size = round_up(init_plts * PLT_ENT_SIZE,
sizeof(struct plt_entries));
mod->arch.init.plt_count = 0;
+ mod->arch.init.plt_ent = NULL;
pr_debug("%s: plt=%x, init.plt=%x\n", __func__,
mod->arch.core.plt->sh_size, mod->arch.init.plt->sh_size);
next prev parent reply other threads:[~2021-09-24 13:10 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-24 12:44 [PATCH 5.10 00/63] 5.10.69-rc1 review Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 01/63] PCI: pci-bridge-emul: Add PCIe Root Capabilities Register Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 02/63] PCI: aardvark: Fix reporting CRS value Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 03/63] console: consume APC, DM, DCS Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 04/63] s390/pci_mmio: fully validate the VMA before calling follow_pte() Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 05/63] ARM: Qualify enabling of swiotlb_init() Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 06/63] ARM: 9077/1: PLT: Move struct plt_entries definition to header Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 07/63] ARM: 9078/1: Add warn suppress parameter to arm_gen_branch_link() Greg Kroah-Hartman
2021-09-24 12:44 ` Greg Kroah-Hartman [this message]
2021-09-24 12:44 ` [PATCH 5.10 09/63] ARM: 9098/1: ftrace: MODULE_PLT: Fix build problem without DYNAMIC_FTRACE Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 10/63] [PATCH] Revert "net/mlx5: Register to devlink ingress VLAN filter trap" Greg Kroah-Hartman
2021-09-27 8:39 ` Tariq Toukan
2021-09-24 12:44 ` [PATCH 5.10 11/63] sctp: validate chunk size in __rcv_asconf_lookup Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 12/63] sctp: add param size validation for SCTP_PARAM_SET_PRIMARY Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 13/63] staging: rtl8192u: Fix bitwise vs logical operator in TranslateRxSignalStuff819xUsb() Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 14/63] coredump: fix memleak in dump_vma_snapshot() Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 15/63] um: virtio_uml: fix memory leak on init failures Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 16/63] dmaengine: acpi: Avoid comparison GSI with Linux vIRQ Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 17/63] perf test: Fix bpf test sample mismatch reporting Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 18/63] perf tools: Allow build-id with trailing zeros Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 19/63] thermal/drivers/exynos: Fix an error code in exynos_tmu_probe() Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 20/63] 9p/trans_virtio: Remove sysfs file on probe failure Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 21/63] prctl: allow to setup brk for et_dyn executables Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 22/63] nilfs2: use refcount_dec_and_lock() to fix potential UAF Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 23/63] profiling: fix shift-out-of-bounds bugs Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 24/63] PM: sleep: core: Avoid setting power.must_resume to false Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 25/63] pwm: lpc32xx: Dont modify HW state in .probe() after the PWM chip was registered Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 26/63] pwm: mxs: " Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 27/63] dmaengine: idxd: fix wq slot allocation index check Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 28/63] platform/chrome: sensorhub: Add trace events for sample Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 29/63] platform/chrome: cros_ec_trace: Fix format warnings Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 30/63] ceph: allow ceph_put_mds_session to take NULL or ERR_PTR Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 31/63] ceph: cancel delayed work instead of flushing on mdsc teardown Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 32/63] Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 33/63] tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 34/63] thermal/core: Fix thermal_cooling_device_register() prototype Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 35/63] drm/amdgpu: Disable PCIE_DPM on Intel RKL Platform Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 36/63] drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION() Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 37/63] dma-buf: DMABUF_MOVE_NOTIFY should depend on DMA_SHARED_BUFFER Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 38/63] parisc: Move pci_dev_is_behind_card_dino to where it is used Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 39/63] iommu/amd: Relocate GAMSup check to early_enable_iommus Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 40/63] dmaengine: idxd: depends on !UML Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 41/63] dmaengine: sprd: Add missing MODULE_DEVICE_TABLE Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 42/63] dmaengine: ioat: depends on !UML Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 43/63] dmaengine: xilinx_dma: Set DMA mask for coherent APIs Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 44/63] ceph: request Fw caps before updating the mtime in ceph_write_iter Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 45/63] ceph: remove the capsnaps when removing caps Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 46/63] ceph: lockdep annotations for try_nonblocking_invalidate Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 47/63] btrfs: update the bdev time directly when closing Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 48/63] btrfs: fix lockdep warning while mounting sprout fs Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 49/63] nilfs2: fix memory leak in nilfs_sysfs_create_device_group Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 50/63] nilfs2: fix NULL pointer in nilfs_##name##_attr_release Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 51/63] nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 52/63] nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 53/63] nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 54/63] nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 55/63] habanalabs: add validity check for event ID received from F/W Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 56/63] pwm: img: Dont modify HW state in .remove() callback Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 57/63] pwm: rockchip: " Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 58/63] pwm: stm32-lp: " Greg Kroah-Hartman
2021-09-24 12:44 ` [PATCH 5.10 59/63] blk-throttle: fix UAF by deleteing timer in blk_throtl_exit() Greg Kroah-Hartman
2021-09-24 12:45 ` [PATCH 5.10 60/63] blk-mq: allow 4x BLK_MAX_REQUEST_COUNT at blk_plug for multiple_queues Greg Kroah-Hartman
2021-09-24 12:45 ` [PATCH 5.10 61/63] rtc: rx8010: select REGMAP_I2C Greg Kroah-Hartman
2021-09-24 12:45 ` [PATCH 5.10 62/63] sched/idle: Make the idle timer expire in hard interrupt context Greg Kroah-Hartman
2021-09-24 12:45 ` [PATCH 5.10 63/63] drm/nouveau/nvkm: Replace -ENOSYS with -ENODEV Greg Kroah-Hartman
2021-09-24 14:12 ` [PATCH 5.10 00/63] 5.10.69-rc1 review Daniel Díaz
2021-09-24 22:11 ` Florian Fainelli
2021-09-25 11:48 ` Greg Kroah-Hartman
2021-09-24 18:05 ` Fox Chen
2021-09-24 21:49 ` Pavel Machek
2021-09-24 21:52 ` Shuah Khan
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