[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 10.557937] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 11.719036] random: crng init done Warning: Permanently added '10.128.0.43' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.515608] ================================================================== [ 37.516921] BUG: KASAN: use-after-free in disk_unblock_events+0x55/0x60 [ 37.517945] Read of size 8 at addr ffff8801cde39660 by task blkid/2120 [ 37.518881] [ 37.519138] CPU: 0 PID: 2120 Comm: blkid Not tainted 4.9.185+ #8 [ 37.520000] ffff8801c570f730 ffffffff81b5a081 0000000000000000 ffffea0007378e00 [ 37.521364] ffff8801cde39660 0000000000000008 ffffffff81b2c645 ffff8801c570f768 [ 37.523349] ffffffff8150ab38 0000000000000000 ffff8801cde39660 ffff8801cde39660 [ 37.524637] Call Trace: [ 37.525102] [<00000000f248a565>] dump_stack+0xc1/0x120 [ 37.525857] [<00000000bfbd0bb7>] ? disk_unblock_events+0x55/0x60 [ 37.526769] [<000000006cf5954c>] print_address_description+0x6f/0x23a [ 37.527797] [<00000000bfbd0bb7>] ? disk_unblock_events+0x55/0x60 [ 37.528672] [<00000000af243fda>] kasan_report.cold+0x8c/0x2ba [ 37.529756] [<0000000052fb1aa5>] __asan_report_load8_noabort+0x14/0x20 [ 37.530671] [<00000000bfbd0bb7>] disk_unblock_events+0x55/0x60 [ 37.531558] [<000000005f46b2db>] __blkdev_get+0x6ba/0xeb0 [ 37.532529] [<0000000035308b2f>] ? __blkdev_put+0x840/0x840 [ 37.533495] [<00000000dd9e16c4>] blkdev_get+0x2e8/0x920 [ 37.534621] [<0000000038f4703a>] ? debug_lockdep_rcu_enabled+0x71/0xa0 [ 37.537164] [<00000000ffcc2519>] ? bd_may_claim+0xd0/0xd0 [ 37.542787] [<000000005c7a2df2>] ? bd_acquire+0x26/0x250 [ 37.548319] [<00000000e232197a>] ? bd_acquire+0x88/0x250 [ 37.553854] [<00000000fc4387d0>] ? _raw_spin_unlock+0x2d/0x50 [ 37.559821] [<000000002474a7fc>] blkdev_open+0x1aa/0x250 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.565353] [<00000000931fbfff>] do_dentry_open+0x422/0xd20 [ 37.571144] [<000000005ecaf87f>] ? blkdev_get_by_dev+0x80/0x80 [ 37.577202] [<0000000074bdb841>] vfs_open+0x105/0x230 [ 37.582481] [<00000000ec8cab7d>] ? may_open.isra.0+0x139/0x290 [ 37.588542] [<00000000df798a40>] path_openat+0xbf5/0x2f60 [ 37.594162] [<00000000ff95439a>] ? path_mountpoint+0x6d0/0x6d0 [ 37.600222] [<00000000a803ec6e>] do_filp_open+0x1a1/0x280 [ 37.605843] [<0000000089c90f7e>] ? may_open_dev+0xe0/0xe0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.611464] [<000000001f310dc9>] ? __alloc_fd+0x1d4/0x490 [ 37.617086] [<00000000fc4387d0>] ? _raw_spin_unlock+0x2d/0x50 [ 37.623055] [<000000001f310dc9>] ? __alloc_fd+0x1d4/0x490 [ 37.628678] [<0000000084cd3b6b>] do_sys_open+0x2f0/0x610 [ 37.634215] [<0000000038b2aa95>] ? filp_open+0x70/0x70 [ 37.639576] [<00000000971bd0b6>] ? __do_page_fault+0x545/0xa60 [ 37.645632] [<000000004cbbe805>] SyS_open+0x2d/0x40 [ 37.650730] [<0000000009ec183b>] ? do_sys_open+0x610/0x610 [ 37.656438] [<0000000035a8a78e>] do_syscall_64+0x1ad/0x5c0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.662150] [<000000009514bdb1>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 37.669067] [ 37.670689] Allocated by task 2111: [ 37.674314] save_stack_trace+0x16/0x20 [ 37.678284] kasan_kmalloc.part.0+0x62/0xf0 [ 37.682686] kasan_kmalloc+0xb7/0xd0 [ 37.686391] kmem_cache_alloc_trace+0x115/0x2d0 [ 37.691057] alloc_disk_node+0x50/0x3c0 [ 37.695022] alloc_disk+0x1b/0x20 [ 37.698469] loop_add+0x37e/0x7d0 [ 37.702004] loop_probe+0x154/0x180 [ 37.705629] kobj_lookup+0x221/0x410 [ 37.709338] get_gendisk+0x3c/0x2d0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.712963] __blkdev_get+0x356/0xeb0 [ 37.716762] blkdev_get+0x2e8/0x920 [ 37.720380] blkdev_open+0x1aa/0x250 [ 37.724086] do_dentry_open+0x422/0xd20 [ 37.728049] vfs_open+0x105/0x230 [ 37.731496] path_openat+0xbf5/0x2f60 [ 37.735355] do_filp_open+0x1a1/0x280 [ 37.739148] do_sys_open+0x2f0/0x610 [ 37.742861] SyS_open+0x2d/0x40 [ 37.746139] do_syscall_64+0x1ad/0x5c0 [ 37.750024] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 37.755110] [ 37.756728] Freed by task 2120: [ 37.760010] save_stack_trace+0x16/0x20 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.763977] kasan_slab_free+0xb0/0x190 [ 37.767948] kfree+0xfc/0x310 [ 37.771049] disk_release+0x255/0x330 [ 37.774844] device_release+0x7d/0x220 [ 37.778729] kobject_put+0x150/0x260 [ 37.782438] put_disk+0x23/0x30 [ 37.785710] __blkdev_get+0x61a/0xeb0 [ 37.789500] blkdev_get+0x2e8/0x920 [ 37.793119] blkdev_open+0x1aa/0x250 [ 37.796828] do_dentry_open+0x422/0xd20 [ 37.800793] vfs_open+0x105/0x230 [ 37.804241] path_openat+0xbf5/0x2f60 [ 37.808037] do_filp_open+0x1a1/0x280 [ 37.811832] do_sys_open+0x2f0/0x610 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.815537] SyS_open+0x2d/0x40 [ 37.818811] do_syscall_64+0x1ad/0x5c0 [ 37.822699] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 37.827785] [ 37.829404] The buggy address belongs to the object at ffff8801cde39100 [ 37.829404] which belongs to the cache kmalloc-2048 of size 2048 [ 37.842226] The buggy address is located 1376 bytes inside of [ 37.842226] 2048-byte region [ffff8801cde39100, ffff8801cde39900) [ 37.854441] The buggy address belongs to the page: executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.859365] page:ffffea0007378e00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 37.869587] flags: 0x4000000000010200(slab|head) [ 37.874331] page dumped because: kasan: bad access detected [ 37.880027] [ 37.881646] Memory state around the buggy address: [ 37.886571] ffff8801cde39500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.893922] ffff8801cde39580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.901285] >ffff8801cde39600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.908633] ^ executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.915118] ffff8801cde39680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.922470] ffff8801cde39700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.929818] ================================================================== [ 37.937171] Disabling lock debugging due to kernel taint [ 37.944543] Kernel panic - not syncing: panic_on_warn set ... [ 37.944543] [ 37.951924] CPU: 0 PID: 2120 Comm: blkid Tainted: G B 4.9.185+ #8 [ 37.959281] ffff8801c570f670 ffffffff81b5a081 ffff8801c570f700 ffffffff82e3f707 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.967350] 00000000ffffffff 0000000000000000 ffffffff81b2c645 ffff8801c570f750 [ 37.975415] ffffffff813fd56a 0000000041b58ab3 ffffffff82e31752 ffffffff813fd391 [ 37.983471] Call Trace: [ 37.986052] [<00000000f248a565>] dump_stack+0xc1/0x120 [ 37.991410] [<00000000bfbd0bb7>] ? disk_unblock_events+0x55/0x60 [ 37.997637] [<00000000fa9de3a5>] panic+0x1d9/0x3bd [ 38.002656] [<000000009b8dcba1>] ? add_taint.cold+0x16/0x16 [ 38.008453] [<00000000ca9d6c1c>] ? preempt_schedule_common+0x4f/0xe0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 38.015035] [<00000000bfbd0bb7>] ? disk_unblock_events+0x55/0x60 [ 38.021272] [<000000008c4fd447>] ? preempt_schedule+0x26/0x30 [ 38.027253] [<00000000156fe32a>] ? ___preempt_schedule+0x16/0x18 [ 38.033490] [<00000000ba2e8394>] kasan_end_report+0x47/0x4f [ 38.039295] [<0000000007f28b24>] kasan_report.cold+0xa9/0x2ba [ 38.045270] [<0000000052fb1aa5>] __asan_report_load8_noabort+0x14/0x20 [ 38.052023] [<00000000bfbd0bb7>] disk_unblock_events+0x55/0x60 [ 38.058078] [<000000005f46b2db>] __blkdev_get+0x6ba/0xeb0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 38.063706] [<0000000035308b2f>] ? __blkdev_put+0x840/0x840 [ 38.069501] [<00000000dd9e16c4>] blkdev_get+0x2e8/0x920 [ 38.074953] [<0000000038f4703a>] ? debug_lockdep_rcu_enabled+0x71/0xa0 [ 38.081707] [<00000000ffcc2519>] ? bd_may_claim+0xd0/0xd0 [ 38.087326] [<000000005c7a2df2>] ? bd_acquire+0x26/0x250 [ 38.092856] [<00000000e232197a>] ? bd_acquire+0x88/0x250 [ 38.098389] [<00000000fc4387d0>] ? _raw_spin_unlock+0x2d/0x50 [ 38.104356] [<000000002474a7fc>] blkdev_open+0x1aa/0x250 [ 38.109905] [<00000000931fbfff>] do_dentry_open+0x422/0xd20 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 38.115706] [<000000005ecaf87f>] ? blkdev_get_by_dev+0x80/0x80 [ 38.121764] [<0000000074bdb841>] vfs_open+0x105/0x230 [ 38.127044] [<00000000ec8cab7d>] ? may_open.isra.0+0x139/0x290 [ 38.133098] [<00000000df798a40>] path_openat+0xbf5/0x2f60 [ 38.138722] [<00000000ff95439a>] ? path_mountpoint+0x6d0/0x6d0 [ 38.144779] [<00000000a803ec6e>] do_filp_open+0x1a1/0x280 [ 38.150407] [<0000000089c90f7e>] ? may_open_dev+0xe0/0xe0 [ 38.156027] [<000000001f310dc9>] ? __alloc_fd+0x1d4/0x490 [ 38.161655] [<00000000fc4387d0>] ? _raw_spin_unlock+0x2d/0x50 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 38.167623] [<000000001f310dc9>] ? __alloc_fd+0x1d4/0x490 [ 38.173245] [<0000000084cd3b6b>] do_sys_open+0x2f0/0x610 [ 38.178776] [<0000000038b2aa95>] ? filp_open+0x70/0x70 [ 38.184134] [<00000000971bd0b6>] ? __do_page_fault+0x545/0xa60 [ 38.190187] [<000000004cbbe805>] SyS_open+0x2d/0x40 [ 38.195282] [<0000000009ec183b>] ? do_sys_open+0x610/0x610 [ 38.200992] [<0000000035a8a78e>] do_syscall_64+0x1ad/0x5c0 [ 38.206698] [<000000009514bdb1>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 38.214148] Kernel Offset: disabled [ 38.217756] Rebooting in 86400 seconds..