[ 39.719010][ T26] audit: type=1800 audit(1557282819.300:27): pid=7521 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [ 39.741445][ T26] audit: type=1800 audit(1557282819.300:28): pid=7521 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. [ 40.537954][ T26] audit: type=1800 audit(1557282820.180:29): pid=7521 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 [ 40.558026][ T26] audit: type=1800 audit(1557282820.180:30): pid=7521 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 '10.128.0.150' (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 syzkaller login: [ 48.764168][ T7729] ================================================================== [ 48.772830][ T7729] BUG: KASAN: use-after-free in __vb2_perform_fileio+0x1065/0x1140 [ 48.780732][ T7729] Read of size 4 at addr ffff8880a029d55c by task syz-executor652/7729 [ 48.788955][ T7729] [ 48.791285][ T7729] CPU: 0 PID: 7729 Comm: syz-executor652 Not tainted 5.1.0+ #2 [ 48.798820][ T7729] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.808870][ T7729] Call Trace: [ 48.812173][ T7729] dump_stack+0x172/0x1f0 [ 48.816509][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.822045][ T7729] print_address_description.cold+0x7c/0x20d [ 48.828032][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.833567][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.839099][ T7729] __kasan_report.cold+0x1b/0x40 [ 48.844156][ T7729] ? __mutex_lock+0x390/0x1310 [ 48.848930][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 48.854515][ T7729] kasan_report+0x12/0x20 [ 48.858835][ T7729] __asan_report_load4_noabort+0x14/0x20 [ 48.864477][ T7729] __vb2_perform_fileio+0x1065/0x1140 [ 48.869848][ T7729] ? aa_path_link+0x460/0x460 [ 48.874639][ T7729] ? vb2_thread_start+0x370/0x370 [ 48.880735][ T7729] ? fsnotify+0x811/0xbc0 [ 48.885071][ T7729] vb2_read+0x3b/0x50 [ 48.889041][ T7729] vb2_fop_read+0x212/0x410 [ 48.893539][ T7729] ? vb2_fop_write+0x410/0x410 [ 48.898300][ T7729] v4l2_read+0x1ce/0x230 [ 48.902536][ T7729] __vfs_read+0x8d/0x110 [ 48.906771][ T7729] ? v4l2_write+0x230/0x230 [ 48.911273][ T7729] vfs_read+0x194/0x3e0 [ 48.915418][ T7729] ksys_read+0x14f/0x2d0 [ 48.919996][ T7729] ? kernel_write+0x120/0x120 [ 48.924666][ T7729] ? do_fast_syscall_32+0xd1/0xd54 [ 48.929873][ T7729] ? entry_SYSENTER_compat+0x70/0x7f [ 48.935152][ T7729] ? do_fast_syscall_32+0xd1/0xd54 [ 48.940258][ T7729] __ia32_sys_read+0x71/0xb0 [ 48.944843][ T7729] do_fast_syscall_32+0x281/0xd54 [ 48.949861][ T7729] entry_SYSENTER_compat+0x70/0x7f [ 48.954959][ T7729] RIP: 0023:0xf7f63849 [ 48.959015][ T7729] Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 [ 48.978692][ T7729] RSP: 002b:00000000ffdc25ac EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 48.987276][ T7729] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000100 [ 48.995239][ T7729] RDX: 0000000000000052 RSI: 0000000000000001 RDI: 00000000ffdc26c4 [ 49.003198][ T7729] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 49.011175][ T7729] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 49.019133][ T7729] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 49.027119][ T7729] [ 49.029448][ T7729] Allocated by task 7725: [ 49.033776][ T7729] save_stack+0x23/0x90 [ 49.037943][ T7729] __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 49.044845][ T7729] kasan_kmalloc+0x9/0x10 [ 49.049175][ T7729] kmem_cache_alloc_trace+0x151/0x760 [ 49.054552][ T7729] __vb2_init_fileio+0x1cb/0xbe0 [ 49.059473][ T7729] __vb2_perform_fileio+0xc01/0x1140 [ 49.064743][ T7729] vb2_read+0x3b/0x50 [ 49.068887][ T7729] vb2_fop_read+0x212/0x410 [ 49.073388][ T7729] v4l2_read+0x1ce/0x230 [ 49.077618][ T7729] __vfs_read+0x8d/0x110 [ 49.081865][ T7729] vfs_read+0x194/0x3e0 [ 49.086022][ T7729] ksys_read+0x14f/0x2d0 [ 49.090260][ T7729] __ia32_sys_read+0x71/0xb0 [ 49.094848][ T7729] do_fast_syscall_32+0x281/0xd54 [ 49.099862][ T7729] entry_SYSENTER_compat+0x70/0x7f [ 49.104960][ T7729] [ 49.107273][ T7729] Freed by task 7727: [ 49.111251][ T7729] save_stack+0x23/0x90 [ 49.115398][ T7729] __kasan_slab_free+0x102/0x150 [ 49.120321][ T7729] kasan_slab_free+0xe/0x10 [ 49.124811][ T7729] kfree+0xcf/0x230 [ 49.128639][ T7729] __vb2_cleanup_fileio+0x100/0x170 [ 49.133823][ T7729] vb2_core_queue_release+0x20/0x80 [ 49.139006][ T7729] _vb2_fop_release+0x1cf/0x2a0 [ 49.143850][ T7729] vb2_fop_release+0x75/0xc0 [ 49.148444][ T7729] vivid_fop_release+0x18e/0x430 [ 49.153371][ T7729] v4l2_release+0x224/0x3a0 [ 49.157867][ T7729] __fput+0x2e5/0x8d0 [ 49.161839][ T7729] ____fput+0x16/0x20 [ 49.165813][ T7729] task_work_run+0x14a/0x1c0 [ 49.170390][ T7729] do_exit+0x90a/0x2fa0 [ 49.174532][ T7729] do_group_exit+0x135/0x370 [ 49.179109][ T7729] __ia32_sys_exit_group+0x44/0x50 [ 49.184317][ T7729] do_fast_syscall_32+0x281/0xd54 [ 49.189348][ T7729] entry_SYSENTER_compat+0x70/0x7f [ 49.194439][ T7729] [ 49.196763][ T7729] The buggy address belongs to the object at ffff8880a029d240 [ 49.196763][ T7729] which belongs to the cache kmalloc-1k of size 1024 [ 49.210921][ T7729] The buggy address is located 796 bytes inside of [ 49.210921][ T7729] 1024-byte region [ffff8880a029d240, ffff8880a029d640) [ 49.224536][ T7729] The buggy address belongs to the page: [ 49.230384][ T7729] page:ffffea000280a700 count:1 mapcount:0 mapping:ffff8880aa400ac0 index:0x0 compound_mapcount: 0 [ 49.241369][ T7729] flags: 0x1fffc0000010200(slab|head) [ 49.246765][ T7729] raw: 01fffc0000010200 ffffea00027ff188 ffffea0002234408 ffff8880aa400ac0 [ 49.255537][ T7729] raw: 0000000000000000 ffff8880a029c040 0000000100000007 0000000000000000 [ 49.264133][ T7729] page dumped because: kasan: bad access detected [ 49.271254][ T7729] [ 49.273573][ T7729] Memory state around the buggy address: [ 49.279195][ T7729] ffff8880a029d400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 49.287694][ T7729] ffff8880a029d480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 49.296306][ T7729] >ffff8880a029d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 49.304354][ T7729] ^ executing program [ 49.311296][ T7729] ffff8880a029d580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 49.319354][ T7729] ffff8880a029d600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 49.327420][ T7729] ================================================================== [ 49.335558][ T7729] Disabling lock debugging due to kernel taint [ 49.344224][ T7729] Kernel panic - not syncing: panic_on_warn set ... [ 49.351376][ T7729] CPU: 0 PID: 7729 Comm: syz-executor652 Tainted: G B 5.1.0+ #2 [ 49.360829][ T7729] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.372280][ T7729] Call Trace: [ 49.375571][ T7729] dump_stack+0x172/0x1f0 [ 49.379899][ T7729] panic+0x2cb/0x65c [ 49.384176][ T7729] ? __warn_printk+0xf3/0xf3 [ 49.390442][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 49.396347][ T7729] ? preempt_schedule+0x4b/0x60 [ 49.401278][ T7729] ? ___preempt_schedule+0x16/0x18 [ 49.407444][ T7729] ? trace_hardirqs_on+0x5e/0x230 [ 49.413309][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 49.418851][ T7729] end_report+0x47/0x4f [ 49.423018][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 49.428655][ T7729] __kasan_report.cold+0xe/0x40 [ 49.433509][ T7729] ? __mutex_lock+0x390/0x1310 [ 49.439002][ T7729] ? __vb2_perform_fileio+0x1065/0x1140 [ 49.445165][ T7729] kasan_report+0x12/0x20 [ 49.449665][ T7729] __asan_report_load4_noabort+0x14/0x20 [ 49.455314][ T7729] __vb2_perform_fileio+0x1065/0x1140 [ 49.460705][ T7729] ? aa_path_link+0x460/0x460 [ 49.465391][ T7729] ? vb2_thread_start+0x370/0x370 [ 49.470400][ T7729] ? fsnotify+0x811/0xbc0 [ 49.474733][ T7729] vb2_read+0x3b/0x50 [ 49.478812][ T7729] vb2_fop_read+0x212/0x410 [ 49.483307][ T7729] ? vb2_fop_write+0x410/0x410 [ 49.488085][ T7729] v4l2_read+0x1ce/0x230 [ 49.492320][ T7729] __vfs_read+0x8d/0x110 [ 49.496548][ T7729] ? v4l2_write+0x230/0x230 [ 49.501125][ T7729] vfs_read+0x194/0x3e0 [ 49.505281][ T7729] ksys_read+0x14f/0x2d0 [ 49.513444][ T7729] ? kernel_write+0x120/0x120 [ 49.526703][ T7729] ? do_fast_syscall_32+0xd1/0xd54 [ 49.531821][ T7729] ? entry_SYSENTER_compat+0x70/0x7f [ 49.537094][ T7729] ? do_fast_syscall_32+0xd1/0xd54 [ 49.542215][ T7729] __ia32_sys_read+0x71/0xb0 [ 49.546807][ T7729] do_fast_syscall_32+0x281/0xd54 [ 49.551992][ T7729] entry_SYSENTER_compat+0x70/0x7f [ 49.557124][ T7729] RIP: 0023:0xf7f63849 [ 49.561186][ T7729] Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 [ 49.580963][ T7729] RSP: 002b:00000000ffdc25ac EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 49.589629][ T7729] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000100 [ 49.597606][ T7729] RDX: 0000000000000052 RSI: 0000000000000001 RDI: 00000000ffdc26c4 [ 49.607847][ T7729] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 49.616032][ T7729] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 49.624103][ T7729] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 49.633642][ T7729] Kernel Offset: disabled [ 49.637974][ T7729] Rebooting in 86400 seconds..