6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sunday Clement commit 40ba09e11188d1b7f79d51fc28aca5ea45e0c138 upstream. KFD_IOC_ALLOC_MEMORY_OF_GPU with flag KFD_IOC_ALLOC_MEM_FLAGS_AQL_QUEUE_MEM and size=1 triggers the AQL wraparound workaround (size >>= 1), reducing size to 0. The resulting zero passes through PAGE_ALIGN(0) = 0 without validation, bypassing the per-process VRAM quota check in reserve_mem_limit() (vram_used + 0 > vram_available is always false). The fix adds post-halving zero-size validation in the primary allocation path (amdgpu_amdkfd_gpuvm.c). The check happens after size halving but before reserve_mem_limit(), and uses err_alignment_size error path to properly clean up the allocated kgd_mem structure and mutex. Cc: stable@vger.kernel.org Signed-off-by: Sunday Clement Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 7 +++++++ drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 3 ++- 2 files changed, 9 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -1777,6 +1777,12 @@ int amdgpu_amdkfd_gpuvm_alloc_memory_of_ size >>= 1; aligned_size = PAGE_ALIGN(size); + /* reject AQL queue with size < 2 */ + if (!aligned_size) { + ret = -EINVAL; + goto err_alignment_size; + } + (*mem)->alloc_flags = flags; amdgpu_sync_create(&(*mem)->sync); @@ -1868,6 +1874,7 @@ err_bo_create: amdgpu_amdkfd_unreserve_mem_limit(adev, aligned_size, flags, xcp_id); err_reserve_limit: amdgpu_sync_free(&(*mem)->sync); +err_alignment_size: mutex_destroy(&(*mem)->lock); if (gobj) drm_gem_object_put(gobj); --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c @@ -1162,7 +1162,8 @@ static int kfd_ioctl_alloc_memory_of_gpu if (flags & KFD_IOC_ALLOC_MEM_FLAGS_AQL_QUEUE_MEM) size >>= 1; - atomic64_add(PAGE_ALIGN(size), &pdd->vram_usage); + size = PAGE_ALIGN(size); + atomic64_add(size, &pdd->vram_usage); } mutex_unlock(&p->mutex);