[PATCH v2 0/4] mm: convert to vma_is_initial_heap/stack()

[PATCH v2 0/4] mm: convert to vma_is_initial_heap/stack()

[Kefeng Wang]

Add vma_is_initial_stack() and vma_is_initial_heap() helper and use
them to simplify code.

v2:
- address comments per David Hildenbrand and Christian Göttsche
- fix selinux build

Kefeng Wang (4):
  mm: factor out VMA stack and heap checks
  drm/amdkfd: use vma_is_initial_stack() and vma_is_initial_heap()
  selinux: use vma_is_initial_stack() and vma_is_initial_heap()
  perf/core: use vma_is_initial_stack() and vma_is_initial_heap()

 drivers/gpu/drm/amd/amdkfd/kfd_svm.c |  5 +----
 fs/proc/task_mmu.c                   | 24 ++++--------------------
 fs/proc/task_nommu.c                 | 15 +--------------
 include/linux/mm.h                   | 21 +++++++++++++++++++++
 kernel/events/core.c                 | 22 +++++++---------------
 security/selinux/hooks.c             |  7 ++-----
 6 files changed, 36 insertions(+), 58 deletions(-)

-- 
2.27.0

[PATCH v2 1/4] mm: factor out VMA stack and heap checks

[Kefeng Wang]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset="yes", Size: 4093 bytes --]

Factor out VMA stack and heap checks and name them
vma_is_initial_stack() and vma_is_initial_heap() for
general use.

Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 fs/proc/task_mmu.c   | 24 ++++--------------------
 fs/proc/task_nommu.c | 15 +--------------
 include/linux/mm.h   | 21 +++++++++++++++++++++
 3 files changed, 26 insertions(+), 34 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 507cd4e59d07..bf25178ae66a 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -236,21 +236,6 @@ static int do_maps_open(struct inode *inode, struct file *file,
 				sizeof(struct proc_maps_private));
 }
 
-/*
- * Indicate if the VMA is a stack for the given task; for
- * /proc/PID/maps that is the stack of the main task.
- */
-static int is_stack(struct vm_area_struct *vma)
-{
-	/*
-	 * We make no effort to guess what a given thread considers to be
-	 * its "stack".  It's not even well-defined for programs written
-	 * languages like Go.
-	 */
-	return vma->vm_start <= vma->vm_mm->start_stack &&
-		vma->vm_end >= vma->vm_mm->start_stack;
-}
-
 static void show_vma_header_prefix(struct seq_file *m,
 				   unsigned long start, unsigned long end,
 				   vm_flags_t flags, unsigned long long pgoff,
@@ -327,13 +312,12 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
 			goto done;
 		}
 
-		if (vma->vm_start <= mm->brk &&
-		    vma->vm_end >= mm->start_brk) {
+		if (vma_is_initial_heap(vma)) {
 			name = "[heap]";
 			goto done;
 		}
 
-		if (is_stack(vma)) {
+		if (vma_is_initial_stack(vma)) {
 			name = "[stack]";
 			goto done;
 		}
@@ -1971,9 +1955,9 @@ static int show_numa_map(struct seq_file *m, void *v)
 	if (file) {
 		seq_puts(m, " file=");
 		seq_file_path(m, file, "\n\t= ");
-	} else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
+	} else if (vma_is_initial_heap(vma)) {
 		seq_puts(m, " heap");
-	} else if (is_stack(vma)) {
+	} else if (vma_is_initial_stack(vma)) {
 		seq_puts(m, " stack");
 	}
 
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 2c8b62265981..a8ac0dd8041e 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -121,19 +121,6 @@ unsigned long task_statm(struct mm_struct *mm,
 	return size;
 }
 
-static int is_stack(struct vm_area_struct *vma)
-{
-	struct mm_struct *mm = vma->vm_mm;
-
-	/*
-	 * We make no effort to guess what a given thread considers to be
-	 * its "stack".  It's not even well-defined for programs written
-	 * languages like Go.
-	 */
-	return vma->vm_start <= mm->start_stack &&
-		vma->vm_end >= mm->start_stack;
-}
-
 /*
  * display a single VMA to a sequenced file
  */
@@ -171,7 +158,7 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
 	if (file) {
 		seq_pad(m, ' ');
 		seq_file_path(m, file, "");
-	} else if (mm && is_stack(vma)) {
+	} else if (mm && vma_is_initial_stack(vma)) {
 		seq_pad(m, ' ');
 		seq_puts(m, "[stack]");
 	}
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 2dd73e4f3d8e..51f8c573db74 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -822,6 +822,27 @@ static inline bool vma_is_anonymous(struct vm_area_struct *vma)
 	return !vma->vm_ops;
 }
 
+static inline bool vma_is_initial_heap(const struct vm_area_struct *vma)
+{
+       return vma->vm_start <= vma->vm_mm->brk &&
+		vma->vm_end >= vma->vm_mm->start_brk;
+}
+
+/*
+ * Indicate if the VMA is a stack for the given task; for
+ * /proc/PID/maps that is the stack of the main task.
+ */
+static inline bool vma_is_initial_stack(const struct vm_area_struct *vma)
+{
+	/*
+	 * We make no effort to guess what a given thread considers to be
+	 * its "stack".  It's not even well-defined for programs written
+	 * languages like Go.
+	 */
+       return vma->vm_start <= vma->vm_mm->start_stack &&
+	       vma->vm_end >= vma->vm_mm->start_stack;
+}
+
 static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
 {
 	int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
-- 
2.27.0

[PATCH v2 2/4] drm/amdkfd: use vma_is_initial_stack() and vma_is_initial_heap()

[Kefeng Wang]

Use the helpers to simplify code.

Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index 5ff1a5a89d96..0b7bfbd0cb66 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -2621,10 +2621,7 @@ svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
 		return -EFAULT;
 	}
 
-	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
-			  vma->vm_end >= vma->vm_mm->start_brk) ||
-			 (vma->vm_start <= vma->vm_mm->start_stack &&
-			  vma->vm_end >= vma->vm_mm->start_stack);
+	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
 
 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
-- 
2.27.0

[PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[Kefeng Wang]

Use the helpers to simplify code.

Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
Cc: Eric Paris <eparis@parisplace.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 security/selinux/hooks.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index d06e350fedee..ee8575540a8e 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
 	if (default_noexec &&
 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
 		int rc = 0;
-		if (vma->vm_start >= vma->vm_mm->start_brk &&
-		    vma->vm_end <= vma->vm_mm->brk) {
+		if (vma_is_initial_heap(vma)) {
 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
 					  PROCESS__EXECHEAP, NULL);
-		} else if (!vma->vm_file &&
-			   ((vma->vm_start <= vma->vm_mm->start_stack &&
-			     vma->vm_end >= vma->vm_mm->start_stack) ||
+		} else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
 			    vma_is_stack_for_current(vma))) {
 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
 					  PROCESS__EXECSTACK, NULL);
-- 
2.27.0

[PATCH v2 4/4] perf/core: use vma_is_initial_stack() and vma_is_initial_heap()

[Kefeng Wang]

Use the helpers to simplify code, also kill unneeded goto cpy_name.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 kernel/events/core.c | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 78ae7b6f90fd..d59f6327472f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8685,22 +8685,14 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 		}
 
 		name = (char *)arch_vma_name(vma);
-		if (name)
-			goto cpy_name;
-
-		if (vma->vm_start <= vma->vm_mm->start_brk &&
-				vma->vm_end >= vma->vm_mm->brk) {
-			name = "[heap]";
-			goto cpy_name;
+		if (!name) {
+			if (vma_is_initial_heap(vma))
+				name = "[heap]";
+			else if (vma_is_initial_stack(vma))
+				name = "[stack]";
+			else
+				name = "//anon";
 		}
-		if (vma->vm_start <= vma->vm_mm->start_stack &&
-				vma->vm_end >= vma->vm_mm->start_stack) {
-			name = "[stack]";
-			goto cpy_name;
-		}
-
-		name = "//anon";
-		goto cpy_name;
 	}
 
 cpy_name:
-- 
2.27.0

Re: [PATCH v2 1/4] mm: factor out VMA stack and heap checks

[David Hildenbrand]

On 19.07.23 09:51, Kefeng Wang wrote:
> Factor out VMA stack and heap checks and name them
> vma_is_initial_stack() and vma_is_initial_heap() for
> general use.
> 
> Cc: Christian Göttsche <cgzones@googlemail.com>
> Cc: David Hildenbrand <david@redhat.com>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---


[...]

> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 2dd73e4f3d8e..51f8c573db74 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -822,6 +822,27 @@ static inline bool vma_is_anonymous(struct vm_area_struct *vma)
>   	return !vma->vm_ops;
>   }
>   

Worth adding a similar comment like for vma_is_initial_stack() ?

> +static inline bool vma_is_initial_heap(const struct vm_area_struct *vma)
> +{
> +       return vma->vm_start <= vma->vm_mm->brk &&
> +		vma->vm_end >= vma->vm_mm->start_brk;
> +}
> +
> +/*
> + * Indicate if the VMA is a stack for the given task; for
> + * /proc/PID/maps that is the stack of the main task.
> + */
> +static inline bool vma_is_initial_stack(const struct vm_area_struct *vma)
> +{
> +	/*
> +	 * We make no effort to guess what a given thread considers to be
> +	 * its "stack".  It's not even well-defined for programs written
> +	 * languages like Go.
> +	 */
> +       return vma->vm_start <= vma->vm_mm->start_stack &&
> +	       vma->vm_end >= vma->vm_mm->start_stack;
> +}
> +
>   static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
>   {
>   	int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb

Re: [PATCH v2 2/4] drm/amdkfd: use vma_is_initial_stack() and vma_is_initial_heap()

[David Hildenbrand]

On 19.07.23 09:51, Kefeng Wang wrote:
> Use the helpers to simplify code.
> 
> Cc: Felix Kuehling <Felix.Kuehling@amd.com>
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: "Christian König" <christian.koenig@amd.com>
> Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
> Cc: David Airlie <airlied@gmail.com>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 5 +----
>   1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index 5ff1a5a89d96..0b7bfbd0cb66 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -2621,10 +2621,7 @@ svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
>   		return -EFAULT;
>   	}
>   
> -	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
> -			  vma->vm_end >= vma->vm_mm->start_brk) ||
> -			 (vma->vm_start <= vma->vm_mm->start_stack &&
> -			  vma->vm_end >= vma->vm_mm->start_stack);
> +	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
>   
>   	start_limit = max(vma->vm_start >> PAGE_SHIFT,
>   		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));

Certainly a valid refactoring, although questionable if such code should 
care about that.

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb

Re: [PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[David Hildenbrand]

On 19.07.23 09:51, Kefeng Wang wrote:
> Use the helpers to simplify code.
> 
> Cc: Paul Moore <paul@paul-moore.com>
> Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
> Cc: Eric Paris <eparis@parisplace.org>
> Acked-by: Paul Moore <paul@paul-moore.com>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>   security/selinux/hooks.c | 7 ++-----
>   1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index d06e350fedee..ee8575540a8e 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
>   	if (default_noexec &&
>   	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
>   		int rc = 0;
> -		if (vma->vm_start >= vma->vm_mm->start_brk &&
> -		    vma->vm_end <= vma->vm_mm->brk) {
> +		if (vma_is_initial_heap(vma)) {
>   			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
>   					  PROCESS__EXECHEAP, NULL);
> -		} else if (!vma->vm_file &&
> -			   ((vma->vm_start <= vma->vm_mm->start_stack &&
> -			     vma->vm_end >= vma->vm_mm->start_stack) ||
> +		} else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
>   			    vma_is_stack_for_current(vma))) {
>   			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
>   					  PROCESS__EXECSTACK, NULL);

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb

Re: [PATCH v2 4/4] perf/core: use vma_is_initial_stack() and vma_is_initial_heap()

[David Hildenbrand]

On 19.07.23 09:51, Kefeng Wang wrote:
> Use the helpers to simplify code, also kill unneeded goto cpy_name.
> 
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>   kernel/events/core.c | 22 +++++++---------------
>   1 file changed, 7 insertions(+), 15 deletions(-)
> 
> diff --git a/kernel/events/core.c b/kernel/events/core.c
> index 78ae7b6f90fd..d59f6327472f 100644
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -8685,22 +8685,14 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
>   		}
>   
>   		name = (char *)arch_vma_name(vma);
> -		if (name)
> -			goto cpy_name;
> -
> -		if (vma->vm_start <= vma->vm_mm->start_brk &&
> -				vma->vm_end >= vma->vm_mm->brk) {
> -			name = "[heap]";
> -			goto cpy_name;
> +		if (!name) {
> +			if (vma_is_initial_heap(vma))
> +				name = "[heap]";
> +			else if (vma_is_initial_stack(vma))
> +				name = "[stack]";
> +			else
> +				name = "//anon";
>   		}
> -		if (vma->vm_start <= vma->vm_mm->start_stack &&
> -				vma->vm_end >= vma->vm_mm->start_stack) {
> -			name = "[stack]";
> -			goto cpy_name;
> -		}
> -
> -		name = "//anon";
> -		goto cpy_name;

If you're removing that goto, maybe also worth removing the goto at the 
end of the previous if branch.

Reviewed-by: David Hildenbrand <david@redhat.com>


-- 
Cheers,

David / dhildenb

Re: [PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[Christian Göttsche]

On Wed, 19 Jul 2023 at 09:40, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>
> Use the helpers to simplify code.
>
> Cc: Paul Moore <paul@paul-moore.com>
> Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
> Cc: Eric Paris <eparis@parisplace.org>
> Acked-by: Paul Moore <paul@paul-moore.com>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> ---
>  security/selinux/hooks.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index d06e350fedee..ee8575540a8e 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
>         if (default_noexec &&
>             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
>                 int rc = 0;
> -               if (vma->vm_start >= vma->vm_mm->start_brk &&
> -                   vma->vm_end <= vma->vm_mm->brk) {
> +               if (vma_is_initial_heap(vma)) {

This seems to change the condition from

    vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk

to

    vma->vm_start <= vma->vm_mm->brk && vma->vm_end >= vma->vm_mm->start_brk

(or AND arguments swapped)

    vma->vm_end >= vma->vm_mm->start_brk && vma->vm_start <= vma->vm_mm->brk

Is this intended?

>                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
>                                           PROCESS__EXECHEAP, NULL);
> -               } else if (!vma->vm_file &&
> -                          ((vma->vm_start <= vma->vm_mm->start_stack &&
> -                            vma->vm_end >= vma->vm_mm->start_stack) ||
> +               } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
>                             vma_is_stack_for_current(vma))) {
>                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
>                                           PROCESS__EXECSTACK, NULL);
> --
> 2.27.0
>

Re: [PATCH v2 4/4] perf/core: use vma_is_initial_stack() and vma_is_initial_heap()

[Peter Zijlstra]

On Wed, Jul 19, 2023 at 03:51:14PM +0800, Kefeng Wang wrote:
> Use the helpers to simplify code, also kill unneeded goto cpy_name.

Grrr.. why am I only getting 4/4 ?

I'm going to write a bot that auto NAKs all partial series :/

Re: [PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[Kefeng Wang]

On 2023/7/19 17:02, Christian Göttsche wrote:
> On Wed, 19 Jul 2023 at 09:40, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>>
>> Use the helpers to simplify code.
>>
>> Cc: Paul Moore <paul@paul-moore.com>
>> Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
>> Cc: Eric Paris <eparis@parisplace.org>
>> Acked-by: Paul Moore <paul@paul-moore.com>
>> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
>> ---
>>   security/selinux/hooks.c | 7 ++-----
>>   1 file changed, 2 insertions(+), 5 deletions(-)
>>
>> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
>> index d06e350fedee..ee8575540a8e 100644
>> --- a/security/selinux/hooks.c
>> +++ b/security/selinux/hooks.c
>> @@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
>>          if (default_noexec &&
>>              (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
>>                  int rc = 0;
>> -               if (vma->vm_start >= vma->vm_mm->start_brk &&
>> -                   vma->vm_end <= vma->vm_mm->brk) {
>> +               if (vma_is_initial_heap(vma)) {
> 
> This seems to change the condition from
> 
>      vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk
> 
> to
> 
>      vma->vm_start <= vma->vm_mm->brk && vma->vm_end >= vma->vm_mm->start_brk
> 
> (or AND arguments swapped)
> 
>      vma->vm_end >= vma->vm_mm->start_brk && vma->vm_start <= vma->vm_mm->brk
> 
> Is this intended?

The new condition is to check whether there is intersection between
[startbrk,brk] and [vm_start,vm_end], it contains orignal check, so
I think it is ok, but for selinux check, I am not sure if there is
some other problem.

> 
>>                          rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
>>                                            PROCESS__EXECHEAP, NULL);
>> -               } else if (!vma->vm_file &&
>> -                          ((vma->vm_start <= vma->vm_mm->start_stack &&
>> -                            vma->vm_end >= vma->vm_mm->start_stack) ||
>> +               } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
>>                              vma_is_stack_for_current(vma))) {
>>                          rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
>>                                            PROCESS__EXECSTACK, NULL);
>> --
>> 2.27.0
>>

Re: [PATCH v2 4/4] perf/core: use vma_is_initial_stack() and vma_is_initial_heap()

[Kefeng Wang]

On 2023/7/19 17:29, Peter Zijlstra wrote:
> On Wed, Jul 19, 2023 at 03:51:14PM +0800, Kefeng Wang wrote:
>> Use the helpers to simplify code, also kill unneeded goto cpy_name.
> 
> Grrr.. why am I only getting 4/4 ?
> 
> I'm going to write a bot that auto NAKs all partial series :/
Sorry, I should add all to cc list, here is all patches linke[1]

[1] 
https://lore.kernel.org/linux-mm/20230719075127.47736-1-wangkefeng.wang@huawei.com/ 


Thanks.
> 

Re: [PATCH v2 2/4] drm/amdkfd: use vma_is_initial_stack() and vma_is_initial_heap()

[Felix Kuehling]

Am 2023-07-19 um 03:51 schrieb Kefeng Wang:
> Use the helpers to simplify code.
>
> Cc: Felix Kuehling <Felix.Kuehling@amd.com>
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: "Christian König" <christian.koenig@amd.com>
> Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
> Cc: David Airlie <airlied@gmail.com>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>


> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 5 +----
>   1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index 5ff1a5a89d96..0b7bfbd0cb66 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -2621,10 +2621,7 @@ svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
>   		return -EFAULT;
>   	}
>   
> -	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
> -			  vma->vm_end >= vma->vm_mm->start_brk) ||
> -			 (vma->vm_start <= vma->vm_mm->start_stack &&
> -			  vma->vm_end >= vma->vm_mm->start_stack);
> +	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
>   
>   	start_limit = max(vma->vm_start >> PAGE_SHIFT,
>   		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));

Re: [PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[Paul Moore]

On Wed, Jul 19, 2023 at 6:23 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> On 2023/7/19 17:02, Christian Göttsche wrote:
> > On Wed, 19 Jul 2023 at 09:40, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> >>
> >> Use the helpers to simplify code.
> >>
> >> Cc: Paul Moore <paul@paul-moore.com>
> >> Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
> >> Cc: Eric Paris <eparis@parisplace.org>
> >> Acked-by: Paul Moore <paul@paul-moore.com>
> >> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> >> ---
> >>   security/selinux/hooks.c | 7 ++-----
> >>   1 file changed, 2 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> >> index d06e350fedee..ee8575540a8e 100644
> >> --- a/security/selinux/hooks.c
> >> +++ b/security/selinux/hooks.c
> >> @@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
> >>          if (default_noexec &&
> >>              (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
> >>                  int rc = 0;
> >> -               if (vma->vm_start >= vma->vm_mm->start_brk &&
> >> -                   vma->vm_end <= vma->vm_mm->brk) {
> >> +               if (vma_is_initial_heap(vma)) {
> >
> > This seems to change the condition from
> >
> >      vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk
> >
> > to
> >
> >      vma->vm_start <= vma->vm_mm->brk && vma->vm_end >= vma->vm_mm->start_brk
> >
> > (or AND arguments swapped)
> >
> >      vma->vm_end >= vma->vm_mm->start_brk && vma->vm_start <= vma->vm_mm->brk
> >
> > Is this intended?
>
> The new condition is to check whether there is intersection between
> [startbrk,brk] and [vm_start,vm_end], it contains orignal check, so
> I think it is ok, but for selinux check, I am not sure if there is
> some other problem.

This particular SELinux vma check is see if the vma falls within the
heap; can you confirm that this change preserves this?

-- 
paul-moore.com

Re: [PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[Kefeng Wang]

On 2023/7/19 23:25, Paul Moore wrote:
> On Wed, Jul 19, 2023 at 6:23 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>> On 2023/7/19 17:02, Christian Göttsche wrote:
>>> On Wed, 19 Jul 2023 at 09:40, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>>>>
>>>> Use the helpers to simplify code.
>>>>
>>>> Cc: Paul Moore <paul@paul-moore.com>
>>>> Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
>>>> Cc: Eric Paris <eparis@parisplace.org>
>>>> Acked-by: Paul Moore <paul@paul-moore.com>
>>>> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
>>>> ---
>>>>    security/selinux/hooks.c | 7 ++-----
>>>>    1 file changed, 2 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
>>>> index d06e350fedee..ee8575540a8e 100644
>>>> --- a/security/selinux/hooks.c
>>>> +++ b/security/selinux/hooks.c
>>>> @@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
>>>>           if (default_noexec &&
>>>>               (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
>>>>                   int rc = 0;
>>>> -               if (vma->vm_start >= vma->vm_mm->start_brk &&
>>>> -                   vma->vm_end <= vma->vm_mm->brk) {
>>>> +               if (vma_is_initial_heap(vma)) {
>>>
>>> This seems to change the condition from
>>>
>>>       vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk
>>>
>>> to
>>>
>>>       vma->vm_start <= vma->vm_mm->brk && vma->vm_end >= vma->vm_mm->start_brk
>>>
>>> (or AND arguments swapped)
>>>
>>>       vma->vm_end >= vma->vm_mm->start_brk && vma->vm_start <= vma->vm_mm->brk
>>>
>>> Is this intended?
>>
>> The new condition is to check whether there is intersection between
>> [startbrk,brk] and [vm_start,vm_end], it contains orignal check, so
>> I think it is ok, but for selinux check, I am not sure if there is
>> some other problem.
> 
> This particular SELinux vma check is see if the vma falls within the
> heap; can you confirm that this change preserves this?

Yes, within is one case of new vma scope check.

> 

Re: [PATCH v2 3/4] selinux: use vma_is_initial_stack() and vma_is_initial_heap()

[Paul Moore]

On Thu, Jul 20, 2023 at 4:28 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> On 2023/7/19 23:25, Paul Moore wrote:
> > On Wed, Jul 19, 2023 at 6:23 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> >> On 2023/7/19 17:02, Christian Göttsche wrote:
> >>> On Wed, 19 Jul 2023 at 09:40, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> >>>>
> >>>> Use the helpers to simplify code.
> >>>>
> >>>> Cc: Paul Moore <paul@paul-moore.com>
> >>>> Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
> >>>> Cc: Eric Paris <eparis@parisplace.org>
> >>>> Acked-by: Paul Moore <paul@paul-moore.com>
> >>>> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> >>>> ---
> >>>>    security/selinux/hooks.c | 7 ++-----
> >>>>    1 file changed, 2 insertions(+), 5 deletions(-)
> >>>>
> >>>> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> >>>> index d06e350fedee..ee8575540a8e 100644
> >>>> --- a/security/selinux/hooks.c
> >>>> +++ b/security/selinux/hooks.c
> >>>> @@ -3762,13 +3762,10 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
> >>>>           if (default_noexec &&
> >>>>               (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
> >>>>                   int rc = 0;
> >>>> -               if (vma->vm_start >= vma->vm_mm->start_brk &&
> >>>> -                   vma->vm_end <= vma->vm_mm->brk) {
> >>>> +               if (vma_is_initial_heap(vma)) {
> >>>
> >>> This seems to change the condition from
> >>>
> >>>       vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk
> >>>
> >>> to
> >>>
> >>>       vma->vm_start <= vma->vm_mm->brk && vma->vm_end >= vma->vm_mm->start_brk
> >>>
> >>> (or AND arguments swapped)
> >>>
> >>>       vma->vm_end >= vma->vm_mm->start_brk && vma->vm_start <= vma->vm_mm->brk
> >>>
> >>> Is this intended?
> >>
> >> The new condition is to check whether there is intersection between
> >> [startbrk,brk] and [vm_start,vm_end], it contains orignal check, so
> >> I think it is ok, but for selinux check, I am not sure if there is
> >> some other problem.
> >
> > This particular SELinux vma check is see if the vma falls within the
> > heap; can you confirm that this change preserves this?
>
> Yes, within is one case of new vma scope check.

Thanks for the confirmation.

-- 
paul-moore.com