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@xxxxxxx> Cc: "Christian König" <christian.koenig@xxxxxxx> Cc: "Pan, Xinhui" <Xinhui.Pan@xxxxxxx> Cc: David Airlie <airlied@xxxxxxxxx> Cc: Daniel Vetter <daniel@xxxxxxxx> Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx> Cc: Luben Tuikov <luben.tuikov@xxxxxxx> Cc: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> Cc: Felix Kuehling <Felix.Kuehling@xxxxxxx> Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: linux-hardening@xxxxxxxxxxxxxxx Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 2 +- drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c index 6f5b641b631e..781e5c5ce04d 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c @@ -84,6 +84,7 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp, kref_init(&list->refcount); + list->num_entries = num_entries; array = list->entries; for (i = 0; i < num_entries; ++i) { @@ -129,7 +130,6 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp, } list->first_userptr = first_userptr; - list->num_entries = num_entries; sort(array, last_entry, sizeof(struct amdgpu_bo_list_entry), amdgpu_bo_list_entry_cmp, NULL); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h index 6a703be45d04..555cd6d877c3 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h @@ -56,7 +56,7 @@ struct amdgpu_bo_list { */ struct mutex bo_list_mutex; - struct amdgpu_bo_list_entry entries[]; + struct amdgpu_bo_list_entry entries[] __counted_by(num_entries); }; int amdgpu_bo_list_get(struct amdgpu_fpriv *fpriv, int id, -- 2.34.1
