Fix out-of-bounds issue in userq fence create when accessing the userq xa structure. Added a lock to protect the race condition.
BUG: KASAN: slab-out-of-bounds in amdgpu_userq_fence_create+0x726/0x880 [amdgpu] [ +0.000006] Call Trace: [ +0.000005] <TASK> [ +0.000005] dump_stack_lvl+0x6c/0x90 [ +0.000011] print_report+0xc4/0x5e0 [ +0.000009] ? srso_return_thunk+0x5/0x5f [ +0.000008] ? kasan_complete_mode_report_info+0x26/0x1d0 [ +0.000007] ? amdgpu_userq_fence_create+0x726/0x880 [amdgpu] [ +0.000405] kasan_report+0xdf/0x120 [ +0.000009] ? amdgpu_userq_fence_create+0x726/0x880 [amdgpu] [ +0.000405] __asan_report_store8_noabort+0x17/0x20 [ +0.000007] amdgpu_userq_fence_create+0x726/0x880 [amdgpu] [ +0.000406] ? __pfx_amdgpu_userq_fence_create+0x10/0x10 [amdgpu] [ +0.000408] ? srso_return_thunk+0x5/0x5f [ +0.000008] ? ttm_resource_move_to_lru_tail+0x235/0x4f0 [ttm] [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000008] amdgpu_userq_signal_ioctl+0xd29/0x1c70 [amdgpu] [ +0.000412] ? __pfx_amdgpu_userq_signal_ioctl+0x10/0x10 [amdgpu] [ +0.000404] ? try_to_wake_up+0x165/0x1840 [ +0.000010] ? __pfx_futex_wake_mark+0x10/0x10 [ +0.000011] drm_ioctl_kernel+0x178/0x2f0 [drm] [ +0.000050] ? __pfx_amdgpu_userq_signal_ioctl+0x10/0x10 [amdgpu] [ +0.000404] ? __pfx_drm_ioctl_kernel+0x10/0x10 [drm] [ +0.000043] ? __kasan_check_read+0x11/0x20 [ +0.000007] ? srso_return_thunk+0x5/0x5f [ +0.000007] ? __kasan_check_write+0x14/0x20 [ +0.000008] drm_ioctl+0x513/0xd20 [drm] [ +0.000040] ? __pfx_amdgpu_userq_signal_ioctl+0x10/0x10 [amdgpu] [ +0.000407] ? __pfx_drm_ioctl+0x10/0x10 [drm] [ +0.000044] ? srso_return_thunk+0x5/0x5f [ +0.000007] ? _raw_spin_lock_irqsave+0x99/0x100 [ +0.000007] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ +0.000006] ? __rseq_handle_notify_resume+0x188/0xc30 [ +0.000008] ? srso_return_thunk+0x5/0x5f [ +0.000008] ? srso_return_thunk+0x5/0x5f [ +0.000006] ? _raw_spin_unlock_irqrestore+0x27/0x50 [ +0.000010] amdgpu_drm_ioctl+0xcd/0x1d0 [amdgpu] [ +0.000388] __x64_sys_ioctl+0x135/0x1b0 [ +0.000009] x64_sys_call+0x1205/0x20d0 [ +0.000007] do_syscall_64+0x4d/0x120 [ +0.000008] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ +0.000007] RIP: 0033:0x7f7c3d31a94f Signed-off-by: Arunpravin Paneer Selvam <arunpravin.paneersel...@amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c index 3a88f754a395..49dc78c2f0d7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c @@ -229,6 +229,7 @@ int amdgpu_userq_fence_create(struct amdgpu_usermode_queue *userq, unsigned long index, count = 0; int i = 0; + xa_lock(&userq->fence_drv_xa); xa_for_each(&userq->fence_drv_xa, index, stored_fence_drv) count++; @@ -240,12 +241,13 @@ int amdgpu_userq_fence_create(struct amdgpu_usermode_queue *userq, if (userq_fence->fence_drv_array) { xa_for_each(&userq->fence_drv_xa, index, stored_fence_drv) { userq_fence->fence_drv_array[i] = stored_fence_drv; - xa_erase(&userq->fence_drv_xa, index); + __xa_erase(&userq->fence_drv_xa, index); i++; } } userq_fence->fence_drv_array_count = i; + xa_unlock(&userq->fence_drv_xa); } else { userq_fence->fence_drv_array = NULL; userq_fence->fence_drv_array_count = 0; -- 2.25.1