[ 36.414829][ T27] audit: type=1800 audit(1557286619.371:27): pid=7544 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [ 36.443425][ T27] audit: type=1800 audit(1557286619.371:28): pid=7544 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. [ 37.365053][ T27] audit: type=1800 audit(1557286620.371:29): pid=7544 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 [ 37.385223][ T27] audit: type=1800 audit(1557286620.371:30): pid=7544 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.19' (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 syzkaller login: [ 48.031119][ T7733] ================================================================== [ 48.039309][ T7733] BUG: KASAN: use-after-free in __vb2_perform_fileio+0x1065/0x1140 [ 48.047185][ T7733] Read of size 4 at addr ffff8880a95cac5c by task syz-executor578/7733 [ 48.055398][ T7733] [ 48.057716][ T7733] CPU: 1 PID: 7733 Comm: syz-executor578 Not tainted 5.1.0+ #2 [ 48.065235][ T7733] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.075270][ T7733] Call Trace: [ 48.078554][ T7733] dump_stack+0x172/0x1f0 [ 48.083366][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.088898][ T7733] print_address_description.cold+0x7c/0x20d [ 48.094858][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.100391][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.105920][ T7733] __kasan_report.cold+0x1b/0x40 [ 48.110847][ T7733] ? __mutex_lock+0x390/0x1310 [ 48.115604][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.121149][ T7733] kasan_report+0x12/0x20 [ 48.125468][ T7733] __asan_report_load4_noabort+0x14/0x20 [ 48.131089][ T7733] __vb2_perform_fileio+0x1065/0x1140 [ 48.136445][ T7733] ? aa_path_link+0x460/0x460 [ 48.141109][ T7733] ? vb2_thread_start+0x370/0x370 [ 48.146121][ T7733] vb2_read+0x3b/0x50 [ 48.150086][ T7733] vb2_fop_read+0x212/0x410 [ 48.154574][ T7733] ? vb2_fop_write+0x410/0x410 [ 48.159323][ T7733] v4l2_read+0x1ce/0x230 [ 48.163552][ T7733] __vfs_read+0x8d/0x110 [ 48.167778][ T7733] ? v4l2_write+0x230/0x230 [ 48.172291][ T7733] vfs_read+0x194/0x3e0 [ 48.176433][ T7733] ksys_read+0x14f/0x2d0 [ 48.180661][ T7733] ? kernel_write+0x120/0x120 [ 48.185331][ T7733] ? do_syscall_64+0x26/0x670 [ 48.190002][ T7733] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.196062][ T7733] ? do_syscall_64+0x26/0x670 [ 48.200728][ T7733] __x64_sys_read+0x73/0xb0 [ 48.205253][ T7733] do_syscall_64+0x103/0x670 [ 48.209838][ T7733] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.215714][ T7733] RIP: 0033:0x444f09 [ 48.219592][ T7733] Code: e8 ac e8 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 0b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 48.239296][ T7733] RSP: 002b:00007fff72c324f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 48.247691][ T7733] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444f09 [ 48.255645][ T7733] RDX: 0000000000000052 RSI: 0000000020000100 RDI: 0000000000000003 [ 48.263599][ T7733] RBP: 000000000000bb6d R08: 0000000000000004 R09: 00000000004002e0 [ 48.271556][ T7733] R10: 000000000000000f R11: 0000000000000246 R12: 00000000004020a0 [ 48.279512][ T7733] R13: 0000000000402130 R14: 0000000000000000 R15: 0000000000000000 [ 48.287488][ T7733] [ 48.289799][ T7733] Allocated by task 7734: [ 48.294132][ T7733] save_stack+0x23/0x90 [ 48.298268][ T7733] __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 48.303877][ T7733] kasan_kmalloc+0x9/0x10 [ 48.308187][ T7733] kmem_cache_alloc_trace+0x151/0x760 [ 48.313544][ T7733] __vb2_init_fileio+0x1cb/0xbe0 [ 48.318461][ T7733] __vb2_perform_fileio+0xc01/0x1140 [ 48.323723][ T7733] vb2_read+0x3b/0x50 [ 48.327684][ T7733] vb2_fop_read+0x212/0x410 [ 48.332187][ T7733] v4l2_read+0x1ce/0x230 [ 48.336413][ T7733] __vfs_read+0x8d/0x110 [ 48.340636][ T7733] vfs_read+0x194/0x3e0 [ 48.344772][ T7733] ksys_read+0x14f/0x2d0 [ 48.349003][ T7733] __x64_sys_read+0x73/0xb0 [ 48.353487][ T7733] do_syscall_64+0x103/0x670 [ 48.358076][ T7733] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.363942][ T7733] [ 48.366254][ T7733] Freed by task 7734: [ 48.370219][ T7733] save_stack+0x23/0x90 [ 48.374357][ T7733] __kasan_slab_free+0x102/0x150 [ 48.379275][ T7733] kasan_slab_free+0xe/0x10 [ 48.383759][ T7733] kfree+0xcf/0x230 [ 48.387551][ T7733] __vb2_cleanup_fileio+0x100/0x170 [ 48.392730][ T7733] vb2_core_queue_release+0x20/0x80 [ 48.397908][ T7733] _vb2_fop_release+0x1cf/0x2a0 [ 48.402740][ T7733] vb2_fop_release+0x75/0xc0 [ 48.407311][ T7733] vivid_fop_release+0x18e/0x430 [ 48.412231][ T7733] v4l2_release+0x224/0x3a0 [ 48.416715][ T7733] __fput+0x2e5/0x8d0 [ 48.420678][ T7733] ____fput+0x16/0x20 [ 48.424642][ T7733] task_work_run+0x14a/0x1c0 [ 48.429215][ T7733] do_exit+0x90a/0x2fa0 [ 48.433349][ T7733] do_group_exit+0x135/0x370 [ 48.437919][ T7733] __x64_sys_exit_group+0x44/0x50 [ 48.442927][ T7733] do_syscall_64+0x103/0x670 [ 48.447501][ T7733] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.453365][ T7733] [ 48.455680][ T7733] The buggy address belongs to the object at ffff8880a95ca940 [ 48.455680][ T7733] which belongs to the cache kmalloc-1k of size 1024 [ 48.469711][ T7733] The buggy address is located 796 bytes inside of [ 48.469711][ T7733] 1024-byte region [ffff8880a95ca940, ffff8880a95cad40) [ 48.483043][ T7733] The buggy address belongs to the page: [ 48.488659][ T7733] page:ffffea0002a57280 count:1 mapcount:0 mapping:ffff8880aa400ac0 index:0x0 compound_mapcount: 0 [ 48.499310][ T7733] flags: 0x1fffc0000010200(slab|head) [ 48.504669][ T7733] raw: 01fffc0000010200 ffffea00024e1608 ffffea00024e1288 ffff8880aa400ac0 [ 48.513234][ T7733] raw: 0000000000000000 ffff8880a95ca040 0000000100000007 0000000000000000 [ 48.521797][ T7733] page dumped because: kasan: bad access detected [ 48.528184][ T7733] [ 48.530489][ T7733] Memory state around the buggy address: [ 48.536103][ T7733] ffff8880a95cab00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.544145][ T7733] ffff8880a95cab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.552188][ T7733] >ffff8880a95cac00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.560226][ T7733] ^ [ 48.567157][ T7733] ffff8880a95cac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.575196][ T7733] ffff8880a95cad00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 48.583252][ T7733] ================================================================== [ 48.591292][ T7733] Disabling lock debugging due to kernel taint [ 48.598473][ T7733] Kernel panic - not syncing: panic_on_warn set ... [ 48.605076][ T7733] CPU: 1 PID: 7733 Comm: syz-executor578 Tainted: G B 5.1.0+ #2 [ 48.613984][ T7733] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.624028][ T7733] Call Trace: [ 48.627309][ T7733] dump_stack+0x172/0x1f0 [ 48.631625][ T7733] panic+0x2cb/0x65c [ 48.635505][ T7733] ? __warn_printk+0xf3/0xf3 [ 48.640086][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.645611][ T7733] ? preempt_schedule+0x4b/0x60 [ 48.650445][ T7733] ? ___preempt_schedule+0x16/0x18 [ 48.655536][ T7733] ? trace_hardirqs_on+0x5e/0x230 [ 48.660543][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.666154][ T7733] end_report+0x47/0x4f [ 48.670294][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.675818][ T7733] __kasan_report.cold+0xe/0x40 [ 48.680651][ T7733] ? __mutex_lock+0x390/0x1310 [ 48.685396][ T7733] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.690926][ T7733] kasan_report+0x12/0x20 [ 48.695245][ T7733] __asan_report_load4_noabort+0x14/0x20 [ 48.700874][ T7733] __vb2_perform_fileio+0x1065/0x1140 [ 48.706227][ T7733] ? aa_path_link+0x460/0x460 [ 48.710891][ T7733] ? vb2_thread_start+0x370/0x370 [ 48.715899][ T7733] vb2_read+0x3b/0x50 [ 48.719863][ T7733] vb2_fop_read+0x212/0x410 [ 48.724349][ T7733] ? vb2_fop_write+0x410/0x410 [ 48.729094][ T7733] v4l2_read+0x1ce/0x230 [ 48.733320][ T7733] __vfs_read+0x8d/0x110 [ 48.737540][ T7733] ? v4l2_write+0x230/0x230 [ 48.742035][ T7733] vfs_read+0x194/0x3e0 [ 48.746171][ T7733] ksys_read+0x14f/0x2d0 [ 48.750394][ T7733] ? kernel_write+0x120/0x120 [ 48.755056][ T7733] ? do_syscall_64+0x26/0x670 [ 48.759717][ T7733] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.765764][ T7733] ? do_syscall_64+0x26/0x670 [ 48.770428][ T7733] __x64_sys_read+0x73/0xb0 [ 48.774926][ T7733] do_syscall_64+0x103/0x670 [ 48.779508][ T7733] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.785382][ T7733] RIP: 0033:0x444f09 [ 48.789259][ T7733] Code: e8 ac e8 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 0b cd fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 48.808840][ T7733] RSP: 002b:00007fff72c324f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 48.817235][ T7733] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444f09 [ 48.825189][ T7733] RDX: 0000000000000052 RSI: 0000000020000100 RDI: 0000000000000003 [ 48.833144][ T7733] RBP: 000000000000bb6d R08: 0000000000000004 R09: 00000000004002e0 [ 48.841109][ T7733] R10: 000000000000000f R11: 0000000000000246 R12: 00000000004020a0 [ 48.849063][ T7733] R13: 0000000000402130 R14: 0000000000000000 R15: 0000000000000000 [ 48.858050][ T7733] Kernel Offset: disabled [ 48.862375][ T7733] Rebooting in 86400 seconds..