[....] Starting enhanced syslogd: rsyslogd[ 12.622538] audit: type=1400 audit(1516118575.838:5): avc: denied { syslog } for pid=3510 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.651916] audit: type=1400 audit(1516118581.867:6): avc: denied { map } for pid=3650 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.15.247' (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 [ 24.888658] audit: type=1400 audit(1516118588.104:7): avc: denied { map } for pid=3664 comm="syzkaller012906" path="/root/syzkaller012906411" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 25.428941] ================================================================== [ 25.436361] BUG: KASAN: use-after-free in disk_unblock_events+0x51/0x60 [ 25.443086] Read of size 8 at addr ffff8801bb4006c0 by task blkid/3832 [ 25.449731] [ 25.451333] CPU: 0 PID: 3832 Comm: blkid Not tainted 4.15.0-rc8-next-20180116+ #98 [ 25.459012] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.468350] Call Trace: [ 25.470922] dump_stack+0x194/0x257 [ 25.474527] ? arch_local_irq_restore+0x53/0x53 [ 25.479169] ? show_regs_print_info+0x18/0x18 [ 25.483650] ? kfree_const+0x31/0x40 [ 25.487337] ? disk_unblock_events+0x51/0x60 [ 25.491720] print_address_description+0x73/0x250 [ 25.496538] ? disk_unblock_events+0x51/0x60 [ 25.500916] kasan_report+0x23b/0x360 [ 25.504693] __asan_report_load8_noabort+0x14/0x20 [ 25.509613] disk_unblock_events+0x51/0x60 [ 25.513824] __blkdev_get+0x869/0x10e0 [ 25.517701] ? __blkdev_put+0x7f0/0x7f0 [ 25.521660] blkdev_get+0x3a1/0xad0 [ 25.525266] ? bd_link_disk_holder+0x8b0/0x8b0 [ 25.529820] ? do_raw_spin_trylock+0x190/0x190 [ 25.534385] ? errseq_sample+0xee/0x140 [ 25.538332] ? _copy_to_user+0xc0/0xc0 [ 25.542195] ? _raw_spin_unlock+0x22/0x30 [ 25.546318] blkdev_open+0x1c9/0x250 [ 25.550002] ? security_file_open+0x89/0x190 [ 25.554384] do_dentry_open+0x667/0xd40 [ 25.558335] ? bd_acquire+0x2c0/0x2c0 [ 25.562111] vfs_open+0x107/0x220 [ 25.565544] path_openat+0x1151/0x3530 [ 25.569417] ? path_lookupat+0xba0/0xba0 [ 25.573461] ? lock_downgrade+0x980/0x980 [ 25.577581] ? do_sys_open+0x2e7/0x6d0 [ 25.581449] ? find_held_lock+0x35/0x1d0 [ 25.585484] ? do_raw_spin_trylock+0x190/0x190 [ 25.590036] ? __lock_is_held+0xb6/0x140 [ 25.594079] ? _raw_spin_unlock+0x22/0x30 [ 25.598212] ? __alloc_fd+0x29b/0x750 [ 25.601996] do_filp_open+0x25b/0x3b0 [ 25.605769] ? may_open_dev+0xe0/0xe0 [ 25.609549] ? mpi_resize+0x200/0x200 [ 25.613326] ? get_unused_fd_flags+0x121/0x190 [ 25.617882] ? getname_flags+0x256/0x580 [ 25.621921] do_sys_open+0x502/0x6d0 [ 25.625604] ? do_sys_open+0x502/0x6d0 [ 25.629467] ? filp_open+0x70/0x70 [ 25.632978] ? entry_SYSCALL_64_fastpath+0x5/0xa0 [ 25.637793] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 25.642786] SyS_open+0x2d/0x40 [ 25.646042] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.650771] RIP: 0033:0x7f63d9312120 [ 25.654457] RSP: 002b:00007ffe42ec2018 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 25.662138] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f63d9312120 [ 25.669380] RDX: 00007ffe42ec3f45 RSI: 0000000000000000 RDI: 00007ffe42ec3f45 [ 25.676628] RBP: 00007ffe42ec3f3d R08: 0000000000000078 R09: 0000000000000000 [ 25.683870] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000009c7030 [ 25.691116] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000005 [ 25.698375] [ 25.699976] Allocated by task 3822: [ 25.703580] save_stack+0x43/0xd0 [ 25.707003] kasan_kmalloc+0xad/0xe0 [ 25.710694] kmem_cache_alloc_node_trace+0x150/0x750 [ 25.715776] __alloc_disk_node+0xb4/0x4e0 [ 25.719896] loop_add+0x44c/0xa70 [ 25.723319] loop_control_ioctl+0x2e9/0x490 [ 25.727614] do_vfs_ioctl+0x1b1/0x1520 [ 25.731471] SyS_ioctl+0x8f/0xc0 [ 25.734810] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.739539] [ 25.741137] Freed by task 3832: [ 25.744412] save_stack+0x43/0xd0 [ 25.747850] __kasan_slab_free+0x11a/0x170 [ 25.752056] kasan_slab_free+0xe/0x10 [ 25.755826] kfree+0xd9/0x260 [ 25.758906] disk_release+0x327/0x410 [ 25.762682] device_release+0x7c/0x210 [ 25.766542] kobject_put+0x14c/0x250 [ 25.770226] put_disk+0x23/0x30 [ 25.773477] __blkdev_get+0x7c9/0x10e0 [ 25.777334] blkdev_get+0x3a1/0xad0 [ 25.780929] blkdev_open+0x1c9/0x250 [ 25.784616] do_dentry_open+0x667/0xd40 [ 25.788560] vfs_open+0x107/0x220 [ 25.791985] path_openat+0x1151/0x3530 [ 25.795846] do_filp_open+0x25b/0x3b0 [ 25.799624] do_sys_open+0x502/0x6d0 [ 25.803309] SyS_open+0x2d/0x40 [ 25.806561] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.811285] [ 25.812885] The buggy address belongs to the object at ffff8801bb400140 [ 25.812885] which belongs to the cache kmalloc-2048 of size 2048 [ 25.825687] The buggy address is located 1408 bytes inside of [ 25.825687] 2048-byte region [ffff8801bb400140, ffff8801bb400940) [ 25.837703] The buggy address belongs to the page: [ 25.842603] page:ffffea0006ed0000 count:1 mapcount:0 mapping:ffff8801bb400140 index:0x0 compound_mapcount: 0 [ 25.852542] flags: 0x2fffc0000008100(slab|head) [ 25.857193] raw: 02fffc0000008100 ffff8801bb400140 0000000000000000 0000000100000003 [ 25.865046] raw: ffffea0006ed14a0 ffffea0007635da0 ffff8801dac00c40 0000000000000000 [ 25.872895] page dumped because: kasan: bad access detected [ 25.878580] [ 25.880177] Memory state around the buggy address: [ 25.885077] ffff8801bb400580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.892408] ffff8801bb400600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.899737] >ffff8801bb400680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.907064] ^ [ 25.912485] ffff8801bb400700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.919815] ffff8801bb400780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 25.927144] ================================================================== [ 25.934470] Disabling lock debugging due to kernel taint [ 25.939982] Kernel panic - not syncing: panic_on_warn set ... [ 25.939982] [ 25.947324] CPU: 0 PID: 3832 Comm: blkid Tainted: G B 4.15.0-rc8-next-20180116+ #98 [ 25.956302] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.965636] Call Trace: [ 25.968212] dump_stack+0x194/0x257 [ 25.971828] ? arch_local_irq_restore+0x53/0x53 [ 25.976479] ? kasan_end_report+0x32/0x50 [ 25.980641] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.985390] ? vsnprintf+0x1ed/0x1900 [ 25.989175] ? del_gendisk+0xa40/0xaa0 [ 25.993044] panic+0x1e4/0x41c [ 25.996217] ? refcount_error_report+0x214/0x214 [ 26.000953] ? add_taint+0x1c/0x50 [ 26.004485] ? add_taint+0x1c/0x50 [ 26.008007] ? disk_unblock_events+0x51/0x60 [ 26.012396] kasan_end_report+0x50/0x50 [ 26.016359] kasan_report+0x148/0x360 [ 26.020144] __asan_report_load8_noabort+0x14/0x20 [ 26.025838] disk_unblock_events+0x51/0x60 [ 26.030054] __blkdev_get+0x869/0x10e0 [ 26.033926] ? __blkdev_put+0x7f0/0x7f0 [ 26.037882] blkdev_get+0x3a1/0xad0 [ 26.041490] ? bd_link_disk_holder+0x8b0/0x8b0 [ 26.046046] ? do_raw_spin_trylock+0x190/0x190 [ 26.050598] ? errseq_sample+0xee/0x140 [ 26.054544] ? _copy_to_user+0xc0/0xc0 [ 26.058403] ? _raw_spin_unlock+0x22/0x30 [ 26.062522] blkdev_open+0x1c9/0x250 [ 26.066205] ? security_file_open+0x89/0x190 [ 26.070589] do_dentry_open+0x667/0xd40 [ 26.074538] ? bd_acquire+0x2c0/0x2c0 [ 26.078311] vfs_open+0x107/0x220 [ 26.081749] path_openat+0x1151/0x3530 [ 26.085612] ? path_lookupat+0xba0/0xba0 [ 26.089644] ? lock_downgrade+0x980/0x980 [ 26.093760] ? do_sys_open+0x2e7/0x6d0 [ 26.097622] ? find_held_lock+0x35/0x1d0 [ 26.101663] ? do_raw_spin_trylock+0x190/0x190 [ 26.106213] ? __lock_is_held+0xb6/0x140 [ 26.110251] ? _raw_spin_unlock+0x22/0x30 [ 26.114370] ? __alloc_fd+0x29b/0x750 [ 26.118148] do_filp_open+0x25b/0x3b0 [ 26.121924] ? may_open_dev+0xe0/0xe0 [ 26.125701] ? mpi_resize+0x200/0x200 [ 26.129478] ? get_unused_fd_flags+0x121/0x190 [ 26.134033] ? getname_flags+0x256/0x580 [ 26.138069] do_sys_open+0x502/0x6d0 [ 26.141754] ? do_sys_open+0x502/0x6d0 [ 26.145625] ? filp_open+0x70/0x70 [ 26.149133] ? entry_SYSCALL_64_fastpath+0x5/0xa0 [ 26.153947] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.158935] SyS_open+0x2d/0x40 [ 26.162187] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 26.166910] RIP: 0033:0x7f63d9312120 [ 26.170592] RSP: 002b:00007ffe42ec2018 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 26.178267] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f63d9312120 [ 26.185506] RDX: 00007ffe42ec3f45 RSI: 0000000000000000 RDI: 00007ffe42ec3f45 [ 26.192755] RBP: 00007ffe42ec3f3d R08: 0000000000000078 R09: 0000000000000000 [ 26.200016] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000009c7030 [ 26.207258] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000005 [ 26.214854] Dumping ftrace buffer: [ 26.218362] (ftrace buffer empty) [ 26.222041] Kernel Offset: disabled [ 26.225647] Rebooting in 86400 seconds..