From: Xiaohui Zhang xiaohuizhang@ruc.edu.cn
[ Upstream commit 0381ac3ca2e727d4dfb7264d9416a8ba6bb6c18b ]
Similar to the handling of amdgpu_sa_bo_next_hole in commit 6a15f3ff19a8 ("drm/amdgpu: Initialize fences array entries in amdgpu_sa_bo_next_hole"), we thought a patch might be needed here as well.
The entries were only initialized once in radeon_sa_bo_new. If a fence wasn't signalled yet in the first radeon_sa_bo_next_hole call, but then got signalled before a later radeon_sa_bo_next_hole call, it could destroy the fence but leave its pointer in the array, resulting in use-after-free in radeon_sa_bo_new.
Signed-off-by: Xiaohui Zhang xiaohuizhang@ruc.edu.cn Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/radeon/radeon_sa.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon_sa.c b/drivers/gpu/drm/radeon/radeon_sa.c index 310c322c7112..0981948bd9ed 100644 --- a/drivers/gpu/drm/radeon/radeon_sa.c +++ b/drivers/gpu/drm/radeon/radeon_sa.c @@ -267,6 +267,8 @@ static bool radeon_sa_bo_next_hole(struct radeon_sa_manager *sa_manager, for (i = 0; i < RADEON_NUM_RINGS; ++i) { struct radeon_sa_bo *sa_bo;
+ fences[i] = NULL; + if (list_empty(&sa_manager->flist[i])) { continue; } @@ -332,10 +334,8 @@ int radeon_sa_bo_new(struct radeon_device *rdev,
spin_lock(&sa_manager->wq.lock); do { - for (i = 0; i < RADEON_NUM_RINGS; ++i) { - fences[i] = NULL; + for (i = 0; i < RADEON_NUM_RINGS; ++i) tries[i] = 0; - }
do { radeon_sa_bo_try_free(sa_manager);