================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x30e0/0x4700 kernel/locking/lockdep.c:3215 Read of size 8 at addr ffff8880a0f27b80 by task syz-executor.0/7728 CPU: 1 PID: 7728 Comm: syz-executor.0 Not tainted 5.0.0-rc8+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135 __lock_acquire+0x30e0/0x4700 kernel/locking/lockdep.c:3215 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3841 __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0xf7/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 seccomp_notify_release+0x62/0x280 kernel/seccomp.c:982 __fput+0x2df/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x411d31 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 94 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007fff4dbf86e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000411d31 RDX: 0000000000000000 RSI: 00000000007402a8 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00000000007402a0 R09: 000000000014747f R10: 00007fff4dbf8600 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000d93 R15: 0000000000000000 Allocated by task 7758: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc mm/kasan/common.c:495 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:509 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3615 kmalloc include/linux/slab.h:545 [inline] kzalloc include/linux/slab.h:740 [inline] seccomp_prepare_filter kernel/seccomp.c:451 [inline] seccomp_prepare_user_filter kernel/seccomp.c:491 [inline] seccomp_set_mode_filter kernel/seccomp.c:1260 [inline] do_seccomp+0x73e/0x2250 kernel/seccomp.c:1374 __do_sys_seccomp kernel/seccomp.c:1393 [inline] __se_sys_seccomp kernel/seccomp.c:1390 [inline] __x64_sys_seccomp+0x73/0xb0 kernel/seccomp.c:1390 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7758: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457 kasan_slab_free+0xe/0x10 mm/kasan/common.c:465 __cache_free mm/slab.c:3494 [inline] kfree+0xcf/0x230 mm/slab.c:3811 seccomp_filter_free kernel/seccomp.c:565 [inline] seccomp_filter_free kernel/seccomp.c:561 [inline] seccomp_set_mode_filter kernel/seccomp.c:1315 [inline] do_seccomp+0xafb/0x2250 kernel/seccomp.c:1374 __do_sys_seccomp kernel/seccomp.c:1393 [inline] __se_sys_seccomp kernel/seccomp.c:1390 [inline] __x64_sys_seccomp+0x73/0xb0 kernel/seccomp.c:1390 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a0f27b00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 128 bytes inside of 192-byte region [ffff8880a0f27b00, ffff8880a0f27bc0) The buggy address belongs to the page: page:ffffea000283c9c0 count:1 mapcount:0 mapping:ffff88812c3f0040 index:0xffff8880a0f27300 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002a231c8 ffffea0002a5e688 ffff88812c3f0040 raw: ffff8880a0f27300 ffff8880a0f27000 000000010000000b 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a0f27a80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ffff8880a0f27b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a0f27b80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8880a0f27c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a0f27c80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ==================================================================