From: Michel Dänzer Date: Wed, 12 Sep 2018 16:07:10 +0000 (+0200) Subject: drm/amdgpu: Initialize fences array entries in amdgpu_sa_bo_next_hole X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=6a15f3ff19a8dd394e3a21480512c2cb98e26b3c;p=openwrt%2Fstaging%2Fblogic.git drm/amdgpu: Initialize fences array entries in amdgpu_sa_bo_next_hole The entries were only initialized once in amdgpu_sa_bo_new. If a fence wasn't signalled yet in the first amdgpu_sa_bo_next_hole call, but then got signalled before a later amdgpu_sa_bo_next_hole call, it could destroy the fence but leave its pointer in the array, resulting in use-after-free in amdgpu_sa_bo_new. Reviewed-by: Christian König Signed-off-by: Michel Dänzer Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c index fb1667b35daa..12f2bf97611f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c @@ -226,6 +226,8 @@ static bool amdgpu_sa_bo_next_hole(struct amdgpu_sa_manager *sa_manager, for (i = 0; i < AMDGPU_SA_NUM_FENCE_LISTS; ++i) { struct amdgpu_sa_bo *sa_bo; + fences[i] = NULL; + if (list_empty(&sa_manager->flist[i])) continue; @@ -296,10 +298,8 @@ int amdgpu_sa_bo_new(struct amdgpu_sa_manager *sa_manager, spin_lock(&sa_manager->wq.lock); do { - for (i = 0; i < AMDGPU_SA_NUM_FENCE_LISTS; ++i) { - fences[i] = NULL; + for (i = 0; i < AMDGPU_SA_NUM_FENCE_LISTS; ++i) tries[i] = 0; - } do { amdgpu_sa_bo_try_free(sa_manager);