diff options
| author | Alysa Liu <Alysa.Liu@amd.com> | 2026-02-05 19:21:45 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-03-25 13:05:53 +0300 |
| commit | c658c1c85ec235b7ecfbf8dbfee385b1332088f4 (patch) | |
| tree | fb8c037a7f0a97f4d32acc52a4a051c2957e4806 /drivers/gpu/drm/amd/amdgpu | |
| parent | 3704ac6a0d9a78f66a187515a8ca3faedaf01cc5 (diff) | |
| download | linux-c658c1c85ec235b7ecfbf8dbfee385b1332088f4.tar.xz | |
drm/amdgpu: Fix use-after-free race in VM acquire
commit 2c1030f2e84885cc58bffef6af67d5b9d2e7098f upstream.
Replace non-atomic vm->process_info assignment with cmpxchg()
to prevent race when parent/child processes sharing a drm_file
both try to acquire the same VM after fork().
Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Alysa Liu <Alysa.Liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit c7c573275ec20db05be769288a3e3bb2250ec618)
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c index c94e1cc7e3a7..b2d86ffc626c 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -1351,7 +1351,10 @@ static int init_kfd_vm(struct amdgpu_vm *vm, void **process_info, *ef = dma_fence_get(&info->eviction_fence->base); } - vm->process_info = *process_info; + if (cmpxchg(&vm->process_info, NULL, *process_info) != NULL) { + ret = -EINVAL; + goto already_acquired; + } /* Validate page directory and attach eviction fence */ ret = amdgpu_bo_reserve(vm->root.bo, true); @@ -1389,6 +1392,7 @@ validate_pd_fail: amdgpu_bo_unreserve(vm->root.bo); reserve_pd_fail: vm->process_info = NULL; +already_acquired: if (info) { /* Two fence references: one in info and one in *ef */ dma_fence_put(&info->eviction_fence->base); |