================================================================== BUG: KASAN: use-after-free in test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:70 [inline] BUG: KASAN: use-after-free in try_to_grab_pending kernel/workqueue.c:1251 [inline] BUG: KASAN: use-after-free in try_to_grab_pending+0x115/0x910 kernel/workqueue.c:1229 Write of size 8 at addr ffff888092f37008 by task syz-executor776/10657 CPU: 0 PID: 10657 Comm: syz-executor776 Not tainted 5.6.0-rc3-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:641 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_write+0x14/0x20 mm/kasan/common.c:101 test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:70 [inline] try_to_grab_pending kernel/workqueue.c:1251 [inline] try_to_grab_pending+0x115/0x910 kernel/workqueue.c:1229 __cancel_work_timer+0xc4/0x540 kernel/workqueue.c:3087 cancel_work_sync+0x18/0x20 kernel/workqueue.c:3164 tty_buffer_cancel_work+0x16/0x20 drivers/tty/tty_buffer.c:613 release_tty+0x261/0x470 drivers/tty/tty_io.c:1520 tty_release_struct+0x3c/0x50 drivers/tty/tty_io.c:1629 tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1789 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xba9/0x2f50 kernel/exit.c:801 do_group_exit+0x135/0x360 kernel/exit.c:899 __do_sys_exit_group kernel/exit.c:910 [inline] __se_sys_exit_group kernel/exit.c:908 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:908 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x43ff38 Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 RSP: 002b:00007ffe97e49478 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 10657: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:515 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] vc_allocate drivers/tty/vt/vt.c:1096 [inline] vc_allocate+0x1fc/0x760 drivers/tty/vt/vt.c:1077 con_install+0x52/0x410 drivers/tty/vt/vt.c:3240 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline] tty_init_dev drivers/tty/tty_io.c:1341 [inline] tty_init_dev+0xf9/0x470 drivers/tty/tty_io.c:1318 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline] tty_open+0x4a5/0xbb0 drivers/tty/tty_io.c:2035 chrdev_open+0x245/0x6b0 fs/char_dev.c:414 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3490 [inline] path_openat+0x12ee/0x3490 fs/namei.c:3607 do_filp_open+0x192/0x260 fs/namei.c:3637 do_sys_openat2+0x5eb/0x7e0 fs/open.c:1149 do_sys_open+0xf2/0x180 fs/open.c:1165 ksys_open include/linux/syscalls.h:1386 [inline] __do_sys_open fs/open.c:1171 [inline] __se_sys_open fs/open.c:1169 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1169 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 10658: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:337 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:476 kasan_slab_free+0xe/0x10 mm/kasan/common.c:485 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 vt_disallocate_all+0x2bd/0x3e0 drivers/tty/vt/vt_ioctl.c:323 vt_ioctl+0xc38/0x26c0 drivers/tty/vt/vt_ioctl.c:816 tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888092f37000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 8 bytes inside of 2048-byte region [ffff888092f37000, ffff888092f37800) The buggy address belongs to the page: page:ffffea00024bcdc0 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002a265c8 ffffea000245e488 ffff8880aa400e00 raw: 0000000000000000 ffff888092f37000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888092f36f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888092f36f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888092f37000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888092f37080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092f37100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================