6.16-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vitaly Prosyak vitaly.prosyak@amd.com
[ Upstream commit a886d26f2c8f9e3f3c1869ae368d09c75daac553 ]
[ +0.000020] BUG: KASAN: slab-use-after-free in amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu] [ +0.000817] Read of size 8 at addr ffff88812eec8c58 by task amd_pci_unplug/1733
[ +0.000027] CPU: 10 UID: 0 PID: 1733 Comm: amd_pci_unplug Tainted: G W 6.14.0+ #2 [ +0.000009] Tainted: [W]=WARN [ +0.000003] Hardware name: ASUS System Product Name/ROG STRIX B550-F GAMING (WI-FI), BIOS 1401 12/03/2020 [ +0.000004] Call Trace: [ +0.000004] <TASK> [ +0.000003] dump_stack_lvl+0x76/0xa0 [ +0.000011] print_report+0xce/0x600 [ +0.000009] ? srso_return_thunk+0x5/0x5f [ +0.000006] ? kasan_complete_mode_report_info+0x76/0x200 [ +0.000007] ? kasan_addr_to_slab+0xd/0xb0 [ +0.000006] ? amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu] [ +0.000707] kasan_report+0xbe/0x110 [ +0.000006] ? amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu] [ +0.000541] __asan_report_load8_noabort+0x14/0x30 [ +0.000005] amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu] [ +0.000535] ? stop_cpsch+0x396/0x600 [amdgpu] [ +0.000556] ? stop_cpsch+0x429/0x600 [amdgpu] [ +0.000536] ? __pfx_amdgpu_userq_suspend+0x10/0x10 [amdgpu] [ +0.000536] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? kgd2kfd_suspend+0x132/0x1d0 [amdgpu] [ +0.000542] amdgpu_device_fini_hw+0x581/0xe90 [amdgpu] [ +0.000485] ? down_write+0xbb/0x140 [ +0.000007] ? __mutex_unlock_slowpath.constprop.0+0x317/0x360 [ +0.000005] ? __pfx_amdgpu_device_fini_hw+0x10/0x10 [amdgpu] [ +0.000482] ? __kasan_check_write+0x14/0x30 [ +0.000004] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? up_write+0x55/0xb0 [ +0.000007] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? blocking_notifier_chain_unregister+0x6c/0xc0 [ +0.000008] amdgpu_driver_unload_kms+0x69/0x90 [amdgpu] [ +0.000484] amdgpu_pci_remove+0x93/0x130 [amdgpu] [ +0.000482] pci_device_remove+0xae/0x1e0 [ +0.000008] device_remove+0xc7/0x180 [ +0.000008] device_release_driver_internal+0x3d4/0x5a0 [ +0.000007] device_release_driver+0x12/0x20 [ +0.000004] pci_stop_bus_device+0x104/0x150 [ +0.000006] pci_stop_and_remove_bus_device_locked+0x1b/0x40 [ +0.000005] remove_store+0xd7/0xf0 [ +0.000005] ? __pfx_remove_store+0x10/0x10 [ +0.000006] ? __pfx__copy_from_iter+0x10/0x10 [ +0.000006] ? __pfx_dev_attr_store+0x10/0x10 [ +0.000006] dev_attr_store+0x3f/0x80 [ +0.000006] sysfs_kf_write+0x125/0x1d0 [ +0.000004] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? __kasan_check_write+0x14/0x30 [ +0.000005] kernfs_fop_write_iter+0x2ea/0x490 [ +0.000005] ? rw_verify_area+0x70/0x420 [ +0.000005] ? __pfx_kernfs_fop_write_iter+0x10/0x10 [ +0.000006] vfs_write+0x90d/0xe70 [ +0.000005] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? __pfx_vfs_write+0x10/0x10 [ +0.000004] ? local_clock+0x15/0x30 [ +0.000008] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? __kasan_slab_free+0x5f/0x80 [ +0.000005] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? __kasan_check_read+0x11/0x20 [ +0.000004] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? fdget_pos+0x1d3/0x500 [ +0.000007] ksys_write+0x119/0x220 [ +0.000005] ? putname+0x1c/0x30 [ +0.000006] ? __pfx_ksys_write+0x10/0x10 [ +0.000007] __x64_sys_write+0x72/0xc0 [ +0.000006] x64_sys_call+0x18ab/0x26f0 [ +0.000006] do_syscall_64+0x7c/0x170 [ +0.000004] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? __pfx___x64_sys_openat+0x10/0x10 [ +0.000006] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? __kasan_check_read+0x11/0x20 [ +0.000003] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? fpregs_assert_state_consistent+0x21/0xb0 [ +0.000006] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? syscall_exit_to_user_mode+0x4e/0x240 [ +0.000005] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? do_syscall_64+0x88/0x170 [ +0.000003] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? irqentry_exit+0x43/0x50 [ +0.000004] ? srso_return_thunk+0x5/0x5f [ +0.000004] ? exc_page_fault+0x7c/0x110 [ +0.000006] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ +0.000006] RIP: 0033:0x7480c0b14887 [ +0.000005] Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 [ +0.000005] RSP: 002b:00007fff142b0058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ +0.000006] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007480c0b14887 [ +0.000003] RDX: 0000000000000001 RSI: 00007480c0e7365a RDI: 0000000000000004 [ +0.000003] RBP: 00007fff142b0080 R08: 0000563b2e73c170 R09: 0000000000000000 [ +0.000003] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff142b02f8 [ +0.000003] R13: 0000563b159a72a9 R14: 0000563b159a9d48 R15: 00007480c0f19040 [ +0.000008] </TASK>
[ +0.000445] Allocated by task 427 on cpu 5 at 29.342331s: [ +0.000011] kasan_save_stack+0x28/0x60 [ +0.000006] kasan_save_track+0x18/0x70 [ +0.000006] kasan_save_alloc_info+0x38/0x60 [ +0.000005] __kasan_kmalloc+0xc1/0xd0 [ +0.000006] __kmalloc_cache_noprof+0x1bd/0x430 [ +0.000007] amdgpu_driver_open_kms+0x172/0x760 [amdgpu] [ +0.000493] drm_file_alloc+0x569/0x9a0 [ +0.000007] drm_client_init+0x1b7/0x410 [ +0.000007] drm_fbdev_client_setup+0x174/0x470 [ +0.000006] drm_client_setup+0x8a/0xf0 [ +0.000006] amdgpu_pci_probe+0x510/0x10c0 [amdgpu] [ +0.000483] local_pci_probe+0xe7/0x1b0 [ +0.000006] pci_device_probe+0x5bf/0x890 [ +0.000006] really_probe+0x1fd/0x950 [ +0.000005] __driver_probe_device+0x307/0x410 [ +0.000006] driver_probe_device+0x4e/0x150 [ +0.000005] __driver_attach+0x223/0x510 [ +0.000006] bus_for_each_dev+0x102/0x1a0 [ +0.000005] driver_attach+0x3d/0x60 [ +0.000006] bus_add_driver+0x309/0x650 [ +0.000005] driver_register+0x13d/0x490 [ +0.000006] __pci_register_driver+0x1ee/0x2b0 [ +0.000006] rfcomm_dlc_clear_state+0x69/0x220 [rfcomm] [ +0.000011] do_one_initcall+0x9c/0x3e0 [ +0.000007] do_init_module+0x29e/0x7f0 [ +0.000006] load_module+0x5c75/0x7c80 [ +0.000006] init_module_from_file+0x106/0x180 [ +0.000006] idempotent_init_module+0x377/0x740 [ +0.000006] __x64_sys_finit_module+0xd7/0x180 [ +0.000006] x64_sys_call+0x1f0b/0x26f0 [ +0.000006] do_syscall_64+0x7c/0x170 [ +0.000005] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ +0.000013] Freed by task 1733 on cpu 5 at 59.907086s: [ +0.000011] kasan_save_stack+0x28/0x60 [ +0.000006] kasan_save_track+0x18/0x70 [ +0.000005] kasan_save_free_info+0x3b/0x60 [ +0.000005] __kasan_slab_free+0x54/0x80 [ +0.000006] kfree+0x127/0x470 [ +0.000006] amdgpu_driver_postclose_kms+0x455/0x760 [amdgpu] [ +0.000493] drm_file_free.part.0+0x5b1/0xba0 [ +0.000006] drm_file_free+0x13/0x30 [ +0.000006] drm_client_release+0x1c4/0x2b0 [ +0.000006] drm_fbdev_ttm_fb_destroy+0xd2/0x120 [drm_ttm_helper] [ +0.000007] put_fb_info+0x97/0xe0 [ +0.000007] unregister_framebuffer+0x197/0x380 [ +0.000005] drm_fb_helper_unregister_info+0x94/0x100 [ +0.000005] drm_fbdev_client_unregister+0x3c/0x80 [ +0.000007] drm_client_dev_unregister+0x144/0x330 [ +0.000006] drm_dev_unregister+0x49/0x1b0 [ +0.000006] drm_dev_unplug+0x4c/0xd0 [ +0.000006] amdgpu_pci_remove+0x58/0x130 [amdgpu] [ +0.000484] pci_device_remove+0xae/0x1e0 [ +0.000008] device_remove+0xc7/0x180 [ +0.000007] device_release_driver_internal+0x3d4/0x5a0 [ +0.000006] device_release_driver+0x12/0x20 [ +0.000007] pci_stop_bus_device+0x104/0x150 [ +0.000006] pci_stop_and_remove_bus_device_locked+0x1b/0x40 [ +0.000006] remove_store+0xd7/0xf0 [ +0.000006] dev_attr_store+0x3f/0x80 [ +0.000005] sysfs_kf_write+0x125/0x1d0 [ +0.000006] kernfs_fop_write_iter+0x2ea/0x490 [ +0.000006] vfs_write+0x90d/0xe70 [ +0.000006] ksys_write+0x119/0x220 [ +0.000006] __x64_sys_write+0x72/0xc0 [ +0.000006] x64_sys_call+0x18ab/0x26f0 [ +0.000005] do_syscall_64+0x7c/0x170 [ +0.000006] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ +0.000012] The buggy address belongs to the object at ffff88812eec8000 which belongs to the cache kmalloc-rnd-07-4k of size 4096 [ +0.000016] The buggy address is located 3160 bytes inside of freed 4096-byte region [ffff88812eec8000, ffff88812eec9000)
[ +0.000023] The buggy address belongs to the physical page: [ +0.000009] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12eec8 [ +0.000007] head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ +0.000005] flags: 0x17ffffc0000040(head|node=0|zone=2|lastcpupid=0x1fffff) [ +0.000007] page_type: f5(slab) [ +0.000008] raw: 0017ffffc0000040 ffff888100054500 dead000000000122 0000000000000000 [ +0.000005] raw: 0000000000000000 0000000080040004 00000000f5000000 0000000000000000 [ +0.000006] head: 0017ffffc0000040 ffff888100054500 dead000000000122 0000000000000000 [ +0.000005] head: 0000000000000000 0000000080040004 00000000f5000000 0000000000000000 [ +0.000006] head: 0017ffffc0000003 ffffea0004bbb201 ffffffffffffffff 0000000000000000 [ +0.000005] head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 [ +0.000005] page dumped because: kasan: bad access detected
[ +0.000010] Memory state around the buggy address: [ +0.000009] ffff88812eec8b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000012] ffff88812eec8b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000011] >ffff88812eec8c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000011] ^ [ +0.000010] ffff88812eec8c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000011] ffff88812eec8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000011] ==================================================================
The use-after-free occurs because a delayed work item (`suspend_work`) may still be pending or running when resources it accesses are freed during device removal or file close. The previous code used `flush_work(&fpriv->evf_mgr.suspend_work.work)`, which does not wait for delayed work that has not yet started. As a result, the delayed work could run after its memory was freed, causing a use-after-free. By switching to `flush_delayed_work(&fpriv->evf_mgr.suspend_work)`, we ensure that the kernel waits for both queued and delayed work to finish before freeing memory, closing this race.
Fixes: adba0929736a ("drm/amdgpu: Fix Illegal opcode in command stream Error") Signed-off-by: Vitaly Prosyak vitaly.prosyak@amd.com Acked-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c index 295e7186e156..aac0de86f3e8 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c @@ -664,7 +664,7 @@ static void amdgpu_userq_restore_worker(struct work_struct *work) struct amdgpu_fpriv *fpriv = uq_mgr_to_fpriv(uq_mgr); int ret;
- flush_work(&fpriv->evf_mgr.suspend_work.work); + flush_delayed_work(&fpriv->evf_mgr.suspend_work);
mutex_lock(&uq_mgr->userq_mutex);