linux.git/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c, branch v7.2 Linux kernel source tree drm/amdgpu: Limit BO list entry count to prevent resource exhaustion 2026-03-17T16:10:16+00:00 Jesse.Zhang Jesse.Zhang@amd.com 2026-03-12T10:06:17+00:00 6270b1a5dab94665d7adce3dc78bc9066ed28bdd Userspace can pass an arbitrary number of BO list entries via the bo_number field. Although the previous multiplication overflow check prevents out-of-bounds allocation, a large number of entries could still cause excessive memory allocation (up to potentially gigabytes) and unnecessarily long list processing times. Introduce a hard limit of 128k entries per BO list, which is more than sufficient for any realistic use case (e.g., a single list containing all buffers in a large scene). This prevents memory exhaustion attacks and ensures predictable performance. Return -EINVAL if the requested entry count exceeds the limit Reviewed-by: Christian König <christian.koenig@amd.com> Suggested-by: Christian König <christian.koenig@amd.com> Signed-off-by: Jesse Zhang <jesse.zhang@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 688b87d39e0aa8135105b40dc167d74b5ada5332) Cc: stable@vger.kernel.org 
Userspace can pass an arbitrary number of BO list entries via the
bo_number field. Although the previous multiplication overflow check
prevents out-of-bounds allocation, a large number of entries could still
cause excessive memory allocation (up to potentially gigabytes) and
unnecessarily long list processing times.

Introduce a hard limit of 128k entries per BO list, which is more than
sufficient for any realistic use case (e.g., a single list containing all
buffers in a large scene). This prevents memory exhaustion attacks and
ensures predictable performance.

Return -EINVAL if the requested entry count exceeds the limit

Reviewed-by: Christian König <christian.koenig@amd.com>
Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jesse Zhang <jesse.zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 688b87d39e0aa8135105b40dc167d74b5ada5332)
Cc: stable@vger.kernel.org
Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-22T01:09:51+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-02-22T01:06:51+00:00 323bbfcf1ef8836d0d2ad9e2c1f1c684f0e3b5b3 This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.

As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21T09:02:28+00:00 Kees Cook kees@kernel.org 2026-02-21T07:49:23+00:00 69050f8d6d075dc01af7a5f2f550a8067510366f This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org> 
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
drm/amdgpu: Simplify sorting of the bo list 2026-01-27T23:08:29+00:00 Tvrtko Ursulin tvrtko.ursulin@igalia.com 2026-01-12T10:22:34+00:00 dda702172dc26e080fe048b8f170eaccb8097c1a Sort function only cares about the sign so we can replace the conditionals with a single subtraction. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Sort function only cares about the sign so we can replace the conditionals
with a single subtraction.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: Use vmemdup_array_user in amdgpu_bo_create_list_entry_array 2025-09-15T20:51:34+00:00 Tvrtko Ursulin tvrtko.ursulin@igalia.com 2025-06-12T10:44:26+00:00 c4ac100e9ae252b09986766ad23b1f83ca3a369d Replace kvmalloc_array() + copy_from_user() with vmemdup_array_user() on the fast path. This shrinks the source code and improves separation between the kernel and userspace slabs. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Replace kvmalloc_array() + copy_from_user() with vmemdup_array_user() on
the fast path.

This shrinks the source code and improves separation between the kernel
and userspace slabs.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: fix error handling in amdgpu_bo_list_get() 2023-11-09T21:59:57+00:00 Christian König christian.koenig@amd.com 2023-11-09T09:12:39+00:00 12f76050d8d4d10dab96333656b821bd4620d103 We should not leak the pointer where we couldn't grab the reference on to the caller because it can be that the error handling still tries to put the reference then. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org 
We should not leak the pointer where we couldn't grab the reference
on to the caller because it can be that the error handling still
tries to put the reference then.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
drm/amdgpu: Annotate struct amdgpu_bo_list with __counted_by 2023-10-05T21:59:35+00:00 Kees Cook keescook@chromium.org 2023-10-03T23:29:52+00:00 c8e7df374ba2ce715ed7f3ceba34efdbfffcb0a9 Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct amdgpu_bo_list. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. 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> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org> Cc: Luben Tuikov <luben.tuikov@amd.com> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: amd-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Cc: linux-hardening@vger.kernel.org Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Reviewed-by: Luben Tuikov <luben.tuikov@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct amdgpu_bo_list.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

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>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-hardening@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: Use kvzalloc() to simplify code 2023-08-30T19:26:47+00:00 Christophe JAILLET christophe.jaillet@wanadoo.fr 2023-08-20T09:51:16+00:00 415b7ba36a788dd2496a605f3fc992c793afd406 kvzalloc() can be used instead of kvmalloc() + memset() + explicit NULL assignments. It is less verbose and more future proof. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
kvzalloc() can be used instead of kvmalloc() + memset() + explicit NULL
assignments.

It is less verbose and more future proof.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: Remove amdgpu_bo_list_array_entry() 2023-08-30T19:26:45+00:00 Christophe JAILLET christophe.jaillet@wanadoo.fr 2023-08-20T09:51:15+00:00 5f5c75bf1687d492d35fb37819508a270ba7a8f8 Now that there is an explicit flexible array at the end of 'struct amdgpu_bo_list', it can be used to remove amdgpu_bo_list_array_entry() and simplify some macro. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Now that there is an explicit flexible array at the end of 'struct
amdgpu_bo_list', it can be used to remove amdgpu_bo_list_array_entry() and
simplify some macro.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: Remove a redundant sanity check 2023-08-30T19:26:38+00:00 Christophe JAILLET christophe.jaillet@wanadoo.fr 2023-08-20T09:51:14+00:00 a23abe1fbdc16358ca185b4681fef19ec75b79c3 The case where 'num_entries' is too big, is already handled by struct_size(), because kvmalloc() would fail. It will return -ENOMEM instead of -EINVAL, but it is only related to a unlikely to happen sanity check. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
The case where 'num_entries' is too big, is already handled by
struct_size(), because kvmalloc() would fail.

It will return -ENOMEM instead of -EINVAL, but it is only related to a
unlikely to happen sanity check.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>