[ 33.944295][ T27] audit: type=1800 audit(1555975670.334:28): pid=7388 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="ssh" dev="sda1" ino=2417 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.461982][ T27] audit: type=1800 audit(1555975670.954:29): pid=7388 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 34.482277][ T27] audit: type=1800 audit(1555975670.964:30): pid=7388 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 [....] startpar: service(s) returned failure: ssh ...[?25l[?1c7[FAIL8[?25h[?0c failed! Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.29' (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 syzkaller login: [ 121.260323][ T7748] ================================================================== [ 121.268576][ T7748] BUG: KASAN: use-after-free in __vb2_perform_fileio+0x1065/0x1140 [ 121.276451][ T7748] Read of size 4 at addr ffff8880a128f55c by task syz-executor650/7748 [ 121.284665][ T7748] [ 121.287130][ T7748] CPU: 0 PID: 7748 Comm: syz-executor650 Not tainted 5.1.0-rc5-next-20190418 #28 [ 121.296232][ T7748] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 121.306412][ T7748] Call Trace: [ 121.309718][ T7748] dump_stack+0x172/0x1f0 [ 121.314055][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.319708][ T7748] print_address_description.cold+0x7c/0x20d [ 121.325687][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.331231][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.336786][ T7748] __kasan_report.cold+0x1b/0x40 [ 121.341730][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.347267][ T7748] kasan_report+0x12/0x20 [ 121.351666][ T7748] __asan_report_load4_noabort+0x14/0x20 [ 121.357315][ T7748] __vb2_perform_fileio+0x1065/0x1140 [ 121.362785][ T7748] ? aa_path_link+0x460/0x460 [ 121.367449][ T7748] ? find_held_lock+0x35/0x130 [ 121.372264][ T7748] ? vb2_thread_start+0x370/0x370 [ 121.377310][ T7748] ? fsnotify+0x811/0xbc0 [ 121.381641][ T7748] vb2_read+0x3b/0x50 [ 121.385621][ T7748] vb2_fop_read+0x212/0x410 [ 121.390130][ T7748] ? vb2_fop_write+0x410/0x410 [ 121.394892][ T7748] v4l2_read+0x1ce/0x230 [ 121.399128][ T7748] __vfs_read+0x8d/0x110 [ 121.403475][ T7748] ? v4l2_write+0x230/0x230 [ 121.408170][ T7748] vfs_read+0x194/0x3e0 [ 121.412329][ T7748] ksys_read+0x14f/0x2d0 [ 121.416588][ T7748] ? kernel_write+0x120/0x120 [ 121.421272][ T7748] ? do_syscall_64+0x26/0x670 [ 121.425939][ T7748] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 121.432088][ T7748] ? do_syscall_64+0x26/0x670 [ 121.436762][ T7748] __x64_sys_read+0x73/0xb0 [ 121.441250][ T7748] do_syscall_64+0x103/0x670 [ 121.445842][ T7748] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 121.451725][ T7748] RIP: 0033:0x44a8e9 [ 121.455601][ T7748] Code: e8 dc e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 4b ca fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 121.475188][ T7748] RSP: 002b:00007f25fbe12db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 121.483594][ T7748] RAX: ffffffffffffffda RBX: 00000000006dcc38 RCX: 000000000044a8e9 [ 121.491564][ T7748] RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000004 [ 121.499568][ T7748] RBP: 00000000006dcc30 R08: 00007f25fbe13700 R09: 0000000000000000 [ 121.507655][ T7748] R10: 00007f25fbe13700 R11: 0000000000000246 R12: 00000000006dcc3c [ 121.515631][ T7748] R13: 00007ffef99db0af R14: 00007f25fbe139c0 R15: 0000000000000001 [ 121.523598][ T7748] [ 121.525915][ T7748] Allocated by task 7748: [ 121.530241][ T7748] save_stack+0x45/0xb0 [ 121.534386][ T7748] __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 121.540018][ T7748] kasan_kmalloc+0x9/0x10 [ 121.544354][ T7748] kmem_cache_alloc_trace+0x151/0x760 [ 121.549724][ T7748] __vb2_init_fileio+0x1cb/0xbe0 [ 121.554650][ T7748] __vb2_perform_fileio+0xc01/0x1140 [ 121.559917][ T7748] vb2_read+0x3b/0x50 [ 121.563882][ T7748] vb2_fop_read+0x212/0x410 [ 121.568370][ T7748] v4l2_read+0x1ce/0x230 [ 121.572712][ T7748] __vfs_read+0x8d/0x110 [ 121.577985][ T7748] vfs_read+0x194/0x3e0 [ 121.582127][ T7748] ksys_read+0x14f/0x2d0 [ 121.586352][ T7748] __x64_sys_read+0x73/0xb0 [ 121.590842][ T7748] do_syscall_64+0x103/0x670 [ 121.595638][ T7748] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 121.601526][ T7748] [ 121.603936][ T7748] Freed by task 7761: [ 121.607913][ T7748] save_stack+0x45/0xb0 [ 121.612054][ T7748] __kasan_slab_free+0x102/0x150 [ 121.616974][ T7748] kasan_slab_free+0xe/0x10 [ 121.621459][ T7748] kfree+0xcf/0x230 [ 121.625262][ T7748] __vb2_cleanup_fileio+0x100/0x170 [ 121.630451][ T7748] vb2_core_queue_release+0x20/0x80 [ 121.635624][ T7748] _vb2_fop_release+0x1cf/0x2a0 [ 121.640452][ T7748] vb2_fop_release+0x75/0xc0 [ 121.645019][ T7748] vivid_fop_release+0x18e/0x430 [ 121.649935][ T7748] v4l2_release+0x224/0x3a0 [ 121.654423][ T7748] __fput+0x2e5/0x8d0 [ 121.658385][ T7748] ____fput+0x16/0x20 [ 121.662454][ T7748] task_work_run+0x14a/0x1c0 [ 121.667144][ T7748] do_exit+0x90a/0x2fa0 [ 121.671283][ T7748] do_group_exit+0x135/0x370 [ 121.675853][ T7748] get_signal+0x399/0x1d50 [ 121.680355][ T7748] do_signal+0x87/0x1900 [ 121.684611][ T7748] exit_to_usermode_loop+0x244/0x2c0 [ 121.689975][ T7748] do_syscall_64+0x57e/0x670 [ 121.694550][ T7748] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 121.700602][ T7748] [ 121.702941][ T7748] The buggy address belongs to the object at ffff8880a128f240 [ 121.702941][ T7748] which belongs to the cache kmalloc-1k of size 1024 [ 121.717085][ T7748] The buggy address is located 796 bytes inside of [ 121.717085][ T7748] 1024-byte region [ffff8880a128f240, ffff8880a128f640) [ 121.730635][ T7748] The buggy address belongs to the page: [ 121.736266][ T7748] page:ffffea000284a380 count:1 mapcount:0 mapping:ffff88812c3deac0 index:0x0 compound_mapcount: 0 [ 121.746920][ T7748] flags: 0x1fffc0000010200(slab|head) [ 121.752611][ T7748] raw: 01fffc0000010200 ffffea0002830a88 ffffea000284ce88 ffff88812c3deac0 [ 121.761277][ T7748] raw: 0000000000000000 ffff8880a128e040 0000000100000007 0000000000000000 [ 121.770044][ T7748] page dumped because: kasan: bad access detected [ 121.776453][ T7748] [ 121.778764][ T7748] Memory state around the buggy address: [ 121.784504][ T7748] ffff8880a128f400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 121.792567][ T7748] ffff8880a128f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 121.800830][ T7748] >ffff8880a128f500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 121.808877][ T7748] ^ [ 121.815818][ T7748] ffff8880a128f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 121.823870][ T7748] ffff8880a128f600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 121.831917][ T7748] ================================================================== [ 121.839959][ T7748] Disabling lock debugging due to kernel taint [ 121.849059][ T7748] Kernel panic - not syncing: panic_on_warn set ... [ 121.855674][ T7748] CPU: 0 PID: 7748 Comm: syz-executor650 Tainted: G B 5.1.0-rc5-next-20190418 #28 [ 121.866161][ T7748] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 121.876207][ T7748] Call Trace: [ 121.879496][ T7748] dump_stack+0x172/0x1f0 [ 121.883806][ T7748] panic+0x2cb/0x72b [ 121.887806][ T7748] ? __warn_printk+0xf3/0xf3 [ 121.892410][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.897942][ T7748] ? preempt_schedule+0x4b/0x60 [ 121.902773][ T7748] ? ___preempt_schedule+0x16/0x18 [ 121.907978][ T7748] ? trace_hardirqs_on+0x5e/0x230 [ 121.913008][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.918539][ T7748] end_report+0x47/0x4f [ 121.922677][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.928203][ T7748] __kasan_report.cold+0xe/0x40 [ 121.933041][ T7748] ? __vb2_perform_fileio+0x1065/0x1140 [ 121.938735][ T7748] kasan_report+0x12/0x20 [ 121.943063][ T7748] __asan_report_load4_noabort+0x14/0x20 [ 121.948701][ T7748] __vb2_perform_fileio+0x1065/0x1140 [ 121.954188][ T7748] ? aa_path_link+0x460/0x460 [ 121.958856][ T7748] ? find_held_lock+0x35/0x130 [ 121.963608][ T7748] ? vb2_thread_start+0x370/0x370 [ 121.968748][ T7748] ? fsnotify+0x811/0xbc0 [ 121.973184][ T7748] vb2_read+0x3b/0x50 [ 121.977179][ T7748] vb2_fop_read+0x212/0x410 [ 121.981685][ T7748] ? vb2_fop_write+0x410/0x410 [ 121.986628][ T7748] v4l2_read+0x1ce/0x230 [ 121.990870][ T7748] __vfs_read+0x8d/0x110 [ 121.995102][ T7748] ? v4l2_write+0x230/0x230 [ 121.999592][ T7748] vfs_read+0x194/0x3e0 [ 122.003729][ T7748] ksys_read+0x14f/0x2d0 [ 122.007970][ T7748] ? kernel_write+0x120/0x120 [ 122.012640][ T7748] ? do_syscall_64+0x26/0x670 [ 122.017298][ T7748] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 122.023346][ T7748] ? do_syscall_64+0x26/0x670 [ 122.028004][ T7748] __x64_sys_read+0x73/0xb0 [ 122.032488][ T7748] do_syscall_64+0x103/0x670 [ 122.037060][ T7748] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 122.042930][ T7748] RIP: 0033:0x44a8e9 [ 122.046904][ T7748] Code: e8 dc e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 4b ca fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 122.066721][ T7748] RSP: 002b:00007f25fbe12db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 122.075195][ T7748] RAX: ffffffffffffffda RBX: 00000000006dcc38 RCX: 000000000044a8e9 [ 122.083193][ T7748] RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000004 [ 122.091164][ T7748] RBP: 00000000006dcc30 R08: 00007f25fbe13700 R09: 0000000000000000 [ 122.099118][ T7748] R10: 00007f25fbe13700 R11: 0000000000000246 R12: 00000000006dcc3c [ 122.107082][ T7748] R13: 00007ffef99db0af R14: 00007f25fbe139c0 R15: 0000000000000001 [ 122.115948][ T7748] Kernel Offset: disabled [ 122.120271][ T7748] Rebooting in 86400 seconds..