[....] Starting enhanced syslogd: rsyslogd[ 13.387924] audit: type=1400 audit(1521121577.046:4): avc: denied { syslog } for pid=3646 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 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[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.23' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 26.466517] ================================================================== [ 26.473896] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 26.480970] Read of size 8 at addr ffff8801c3000140 by task syzkaller503191/3803 [ 26.488472] [ 26.490076] CPU: 1 PID: 3803 Comm: syzkaller503191 Not tainted 4.9.87-g3a3a084 #56 [ 26.497755] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.507081] ffff8801d7cb7a60 ffffffff81d95a19 ffffea00070c0000 ffff8801c3000140 [ 26.515051] 0000000000000000 ffff8801c3000140 ffff8801b3ed4438 ffff8801d7cb7a98 [ 26.523015] ffffffff8153e333 ffff8801c3000140 0000000000000008 0000000000000000 [ 26.530986] Call Trace: [ 26.533544] [] dump_stack+0xc1/0x128 [ 26.538879] [] print_address_description+0x73/0x280 [ 26.545511] [] kasan_report+0x275/0x360 [ 26.551107] [] ? sg_remove_request+0x103/0x120 [ 26.557314] [] __asan_report_load8_noabort+0x14/0x20 [ 26.564043] [] sg_remove_request+0x103/0x120 [ 26.570073] [] sg_finish_rem_req+0x295/0x340 [ 26.576098] [] sg_read+0xa16/0x1440 [ 26.581345] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.587978] [] ? fasync_insert_entry+0x147/0x2e0 [ 26.594351] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.600989] [] __vfs_read+0x103/0x670 [ 26.606408] [] ? default_llseek+0x290/0x290 [ 26.612346] [] ? fsnotify+0x86/0xf30 [ 26.617677] [] ? fsnotify+0xf30/0xf30 [ 26.623097] [] ? avc_policy_seqno+0x9/0x20 [ 26.628952] [] ? selinux_file_permission+0x82/0x460 [ 26.635606] [] ? security_file_permission+0x89/0x1e0 [ 26.642330] [] ? rw_verify_area+0xe5/0x2b0 [ 26.648181] [] vfs_read+0x11e/0x380 [ 26.653425] [] SyS_read+0xd9/0x1b0 [ 26.658582] [] ? vfs_copy_file_range+0x740/0x740 [ 26.664956] [] ? do_syscall_64+0x48/0x490 [ 26.670724] [] ? vfs_copy_file_range+0x740/0x740 [ 26.677102] [] do_syscall_64+0x1a4/0x490 [ 26.682785] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 26.689679] [ 26.691275] Allocated by task 0: [ 26.694606] (stack is not available) [ 26.698286] [ 26.699889] Freed by task 0: [ 26.702871] (stack is not available) [ 26.706550] [ 26.708145] The buggy address belongs to the object at ffff8801c3000100 [ 26.708145] which belongs to the cache fasync_cache of size 96 [ 26.720772] The buggy address is located 64 bytes inside of [ 26.720772] 96-byte region [ffff8801c3000100, ffff8801c3000160) [ 26.732442] The buggy address belongs to the page: [ 26.737343] page:ffffea00070c0000 count:1 mapcount:0 mapping: (null) index:0x0 [ 26.745578] flags: 0x8000000000000080(slab) [ 26.749862] page dumped because: kasan: bad access detected [ 26.755538] [ 26.757134] Memory state around the buggy address: [ 26.762031] ffff8801c3000000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 26.769355] ffff8801c3000080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.776689] >ffff8801c3000100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.784020] ^ [ 26.789440] ffff8801c3000180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.796765] ffff8801c3000200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.804089] ================================================================== [ 26.811411] Disabling lock debugging due to kernel taint [ 26.817118] Kernel panic - not syncing: panic_on_warn set ... [ 26.817118] [ 26.824462] CPU: 1 PID: 3803 Comm: syzkaller503191 Tainted: G B 4.9.87-g3a3a084 #56 [ 26.833350] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.842677] ffff8801d7cb79b8 ffffffff81d95a19 ffffffff84197bf7 ffff8801d7cb7a90 [ 26.850643] 0000000000000000 ffff8801c3000140 ffff8801b3ed4438 ffff8801d7cb7a80 [ 26.858619] ffffffff8142f7e1 0000000041b58ab3 ffffffff8418b658 ffffffff8142f625 [ 26.866589] Call Trace: [ 26.869150] [] dump_stack+0xc1/0x128 [ 26.874488] [] panic+0x1bc/0x3a8 [ 26.879474] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 26.887674] [] ? preempt_schedule+0x25/0x30 [ 26.893615] [] ? ___preempt_schedule+0x16/0x18 [ 26.899820] [] kasan_end_report+0x50/0x50 [ 26.905586] [] kasan_report+0x167/0x360 [ 26.911177] [] ? sg_remove_request+0x103/0x120 [ 26.917390] [] __asan_report_load8_noabort+0x14/0x20 [ 26.924123] [] sg_remove_request+0x103/0x120 [ 26.930155] [] sg_finish_rem_req+0x295/0x340 [ 26.936187] [] sg_read+0xa16/0x1440 [ 26.941437] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.948070] [] ? fasync_insert_entry+0x147/0x2e0 [ 26.954445] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.961079] [] __vfs_read+0x103/0x670 [ 26.966504] [] ? default_llseek+0x290/0x290 [ 26.972441] [] ? fsnotify+0x86/0xf30 [ 26.977771] [] ? fsnotify+0xf30/0xf30 [ 26.983189] [] ? avc_policy_seqno+0x9/0x20 [ 26.989041] [] ? selinux_file_permission+0x82/0x460 [ 26.995675] [] ? security_file_permission+0x89/0x1e0 [ 27.002395] [] ? rw_verify_area+0xe5/0x2b0 [ 27.008245] [] vfs_read+0x11e/0x380 [ 27.013487] [] SyS_read+0xd9/0x1b0 [ 27.018643] [] ? vfs_copy_file_range+0x740/0x740 [ 27.025015] [] ? do_syscall_64+0x48/0x490 [ 27.030782] [] ? vfs_copy_file_range+0x740/0x740 [ 27.037152] [] do_syscall_64+0x1a4/0x490 [ 27.042834] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 27.050191] Dumping ftrace buffer: [ 27.053702] (ftrace buffer empty) [ 27.057381] Kernel Offset: disabled [ 27.060976] Rebooting in 86400 seconds..