================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x2d5e/0x3fb0 kernel/locking/lockdep.c:3573 Read of size 8 at addr ffff888085848380 by task syz-executor.1/23267 CPU: 0 PID: 23267 Comm: syz-executor.1 Not tainted 5.1.0-rc1-next-20190322 #9 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:132 __lock_acquire+0x2d5e/0x3fb0 kernel/locking/lockdep.c:3573 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4211 __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:984 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:980 get_signal+0x399/0x1d50 kernel/signal.c:2577 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162 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: 0033:0x458209 Code: 4c 24 08 48 c7 44 24 10 00 00 00 00 48 89 54 24 18 e8 ab 9f ff ff 48 8b 6c 24 20 48 83 c4 28 c3 e8 ac 1c 00 00 eb aa cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 40 RSP: 002b:00007f62deb66cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000073bf08 RCX: 0000000000458209 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000073bf08 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000073bf0c R13: 00007ffd1d78aa7f R14: 00007f62deb679c0 R15: 000000000073bf0c Allocated by task 23298: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:511 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3621 kmalloc include/linux/slab.h:545 [inline] kzalloc include/linux/slab.h:740 [inline] seccomp_prepare_filter kernel/seccomp.c:453 [inline] seccomp_prepare_user_filter kernel/seccomp.c:493 [inline] seccomp_set_mode_filter kernel/seccomp.c:1262 [inline] do_seccomp+0x743/0x2250 kernel/seccomp.c:1376 __do_sys_seccomp kernel/seccomp.c:1395 [inline] __se_sys_seccomp kernel/seccomp.c:1392 [inline] __x64_sys_seccomp+0x73/0xb0 kernel/seccomp.c:1392 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 23298: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3821 seccomp_filter_free kernel/seccomp.c:567 [inline] seccomp_filter_free kernel/seccomp.c:563 [inline] seccomp_set_mode_filter kernel/seccomp.c:1317 [inline] do_seccomp+0xb00/0x2250 kernel/seccomp.c:1376 __do_sys_seccomp kernel/seccomp.c:1395 [inline] __se_sys_seccomp kernel/seccomp.c:1392 [inline] __x64_sys_seccomp+0x73/0xb0 kernel/seccomp.c:1392 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 ffff888085848300 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 128 bytes inside of 192-byte region [ffff888085848300, ffff8880858483c0) The buggy address belongs to the page: page:ffffea0002161200 count:1 mapcount:0 mapping:ffff88812c3f0040 index:0xffff888085848900 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026f81c8 ffffea0002a57f48 ffff88812c3f0040 raw: ffff888085848900 ffff888085848000 000000010000000d 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888085848280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888085848300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888085848380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888085848400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888085848480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================