[ 44.010698][ T26] audit: type=1800 audit(1556007984.186:30): pid=7938 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [....] 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 syzkaller login: [ 48.463653][ T26] kauditd_printk_skb: 4 callbacks suppressed [ 48.463668][ T26] audit: type=1400 audit(1556007988.676:35): avc: denied { map } for pid=8110 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 '10.128.10.4' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program [ 54.880147][ T26] audit: type=1400 audit(1556007995.086:36): avc: denied { map } for pid=8122 comm="syz-executor885" path="/root/syz-executor885422267" dev="sda1" ino=16483 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 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 [ 55.728882][ T8235] ================================================================== [ 55.737180][ T8235] BUG: KASAN: use-after-free in __vb2_perform_fileio+0x1065/0x1140 [ 55.745099][ T8235] Read of size 4 at addr ffff8880a16170dc by task syz-executor885/8235 [ 55.753432][ T8235] [ 55.755762][ T8235] CPU: 1 PID: 8235 Comm: syz-executor885 Not tainted 5.1.0-rc6 #78 [ 55.763632][ T8235] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 55.773678][ T8235] Call Trace: [ 55.776990][ T8235] dump_stack+0x172/0x1f0 [ 55.781317][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 55.786870][ T8235] print_address_description.cold+0x7c/0x20d [ 55.792848][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 55.798388][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 55.803962][ T8235] kasan_report.cold+0x1b/0x40 [ 55.808763][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 55.814320][ T8235] __asan_report_load4_noabort+0x14/0x20 [ 55.819970][ T8235] __vb2_perform_fileio+0x1065/0x1140 [ 55.825356][ T8235] ? vb2_thread_start+0x370/0x370 [ 55.830408][ T8235] vb2_read+0x3b/0x50 [ 55.834413][ T8235] vb2_fop_read+0x212/0x410 [ 55.838906][ T8235] ? vb2_fop_write+0x410/0x410 [ 55.843682][ T8235] v4l2_read+0x1ce/0x230 [ 55.847932][ T8235] __vfs_read+0x8d/0x110 [ 55.852198][ T8235] ? v4l2_write+0x230/0x230 [ 55.856747][ T8235] vfs_read+0x194/0x3e0 [ 55.860906][ T8235] ksys_read+0x14f/0x2d0 [ 55.865192][ T8235] ? kernel_write+0x120/0x120 [ 55.869909][ T8235] ? do_syscall_64+0x26/0x610 [ 55.874585][ T8235] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 55.880653][ T8235] ? do_syscall_64+0x26/0x610 [ 55.885325][ T8235] __x64_sys_read+0x73/0xb0 [ 55.889831][ T8235] do_syscall_64+0x103/0x610 [ 55.894434][ T8235] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 55.900329][ T8235] RIP: 0033:0x444f19 [ 55.904221][ T8235] 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 [ 55.923822][ T8235] RSP: 002b:00007ffcf6942a68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 55.932236][ T8235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444f19 [ 55.940234][ T8235] RDX: 0000000000000052 RSI: 0000000020000540 RDI: 0000000000000003 [ 55.948374][ T8235] RBP: 000000000000d970 R08: 00000000004002e0 R09: 00000000004002e0 [ 55.956370][ T8235] R10: 000000000000000f R11: 0000000000000246 R12: 00000000004020b0 [ 55.964378][ T8235] R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000 [ 55.972616][ T8235] [ 55.974928][ T8235] Allocated by task 8232: [ 55.979254][ T8235] save_stack+0x45/0xd0 [ 55.983415][ T8235] __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 55.989039][ T8235] kasan_kmalloc+0x9/0x10 [ 55.993356][ T8235] kmem_cache_alloc_trace+0x151/0x760 [ 55.998735][ T8235] __vb2_init_fileio+0x1cb/0xbe0 [ 56.003661][ T8235] __vb2_perform_fileio+0xc01/0x1140 [ 56.008933][ T8235] vb2_read+0x3b/0x50 [ 56.012986][ T8235] vb2_fop_read+0x212/0x410 [ 56.017506][ T8235] v4l2_read+0x1ce/0x230 [ 56.021738][ T8235] __vfs_read+0x8d/0x110 [ 56.025993][ T8235] vfs_read+0x194/0x3e0 [ 56.030185][ T8235] ksys_read+0x14f/0x2d0 [ 56.034433][ T8235] __x64_sys_read+0x73/0xb0 [ 56.038939][ T8235] do_syscall_64+0x103/0x610 [ 56.043519][ T8235] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 56.049480][ T8235] [ 56.051810][ T8235] Freed by task 8236: [ 56.055793][ T8235] save_stack+0x45/0xd0 [ 56.059939][ T8235] __kasan_slab_free+0x102/0x150 [ 56.064913][ T8235] kasan_slab_free+0xe/0x10 [ 56.069611][ T8235] kfree+0xcf/0x230 [ 56.073431][ T8235] __vb2_cleanup_fileio+0x100/0x170 [ 56.078629][ T8235] vb2_core_queue_release+0x20/0x80 [ 56.083822][ T8235] _vb2_fop_release+0x1cf/0x2a0 [ 56.088674][ T8235] vb2_fop_release+0x75/0xc0 [ 56.093293][ T8235] vivid_fop_release+0x18e/0x430 [ 56.098241][ T8235] v4l2_release+0x224/0x3a0 [ 56.102762][ T8235] __fput+0x2e5/0x8d0 [ 56.106731][ T8235] ____fput+0x16/0x20 [ 56.110715][ T8235] task_work_run+0x14a/0x1c0 [ 56.115411][ T8235] do_exit+0x90a/0x2fa0 [ 56.119581][ T8235] do_group_exit+0x135/0x370 [ 56.124198][ T8235] __x64_sys_exit_group+0x44/0x50 [ 56.129515][ T8235] do_syscall_64+0x103/0x610 [ 56.134144][ T8235] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 56.140021][ T8235] [ 56.142358][ T8235] The buggy address belongs to the object at ffff8880a1616dc0 [ 56.142358][ T8235] which belongs to the cache kmalloc-1k of size 1024 [ 56.156416][ T8235] The buggy address is located 796 bytes inside of [ 56.156416][ T8235] 1024-byte region [ffff8880a1616dc0, ffff8880a16171c0) [ 56.169783][ T8235] The buggy address belongs to the page: [ 56.175421][ T8235] page:ffffea0002858580 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0 [ 56.186112][ T8235] flags: 0x1fffc0000010200(slab|head) [ 56.191493][ T8235] raw: 01fffc0000010200 ffffea0002678d88 ffffea00028f4608 ffff88812c3f0ac0 [ 56.200087][ T8235] raw: 0000000000000000 ffff8880a1616040 0000000100000007 0000000000000000 [ 56.208676][ T8235] page dumped because: kasan: bad access detected [ 56.215141][ T8235] [ 56.217455][ T8235] Memory state around the buggy address: [ 56.223072][ T8235] ffff8880a1616f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.231129][ T8235] ffff8880a1617000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.239281][ T8235] >ffff8880a1617080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.247445][ T8235] ^ [ 56.254409][ T8235] ffff8880a1617100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.262471][ T8235] ffff8880a1617180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 56.270526][ T8235] ================================================================== [ 56.278839][ T8235] Disabling lock debugging due to kernel taint [ 56.286420][ T8235] Kernel panic - not syncing: panic_on_warn set ... [ 56.293037][ T8235] CPU: 1 PID: 8235 Comm: syz-executor885 Tainted: G B 5.1.0-rc6 #78 [ 56.302342][ T8235] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 56.312541][ T8235] Call Trace: [ 56.315833][ T8235] dump_stack+0x172/0x1f0 [ 56.320168][ T8235] panic+0x2cb/0x65c [ 56.324066][ T8235] ? __warn_printk+0xf3/0xf3 [ 56.328641][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 56.334187][ T8235] ? preempt_schedule+0x4b/0x60 [ 56.339065][ T8235] ? ___preempt_schedule+0x16/0x18 [ 56.344185][ T8235] ? trace_hardirqs_on+0x5e/0x230 [ 56.349205][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 56.354741][ T8235] end_report+0x47/0x4f [ 56.358880][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 56.364408][ T8235] kasan_report.cold+0xe/0x40 [ 56.369081][ T8235] ? __vb2_perform_fileio+0x1065/0x1140 [ 56.374643][ T8235] __asan_report_load4_noabort+0x14/0x20 [ 56.380289][ T8235] __vb2_perform_fileio+0x1065/0x1140 [ 56.385663][ T8235] ? vb2_thread_start+0x370/0x370 [ 56.390728][ T8235] vb2_read+0x3b/0x50 [ 56.394798][ T8235] vb2_fop_read+0x212/0x410 [ 56.399286][ T8235] ? vb2_fop_write+0x410/0x410 [ 56.404050][ T8235] v4l2_read+0x1ce/0x230 [ 56.408279][ T8235] __vfs_read+0x8d/0x110 [ 56.412516][ T8235] ? v4l2_write+0x230/0x230 [ 56.417029][ T8235] vfs_read+0x194/0x3e0 [ 56.421193][ T8235] ksys_read+0x14f/0x2d0 [ 56.425448][ T8235] ? kernel_write+0x120/0x120 [ 56.430127][ T8235] ? do_syscall_64+0x26/0x610 [ 56.434802][ T8235] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 56.440866][ T8235] ? do_syscall_64+0x26/0x610 [ 56.445528][ T8235] __x64_sys_read+0x73/0xb0 [ 56.450018][ T8235] do_syscall_64+0x103/0x610 [ 56.454602][ T8235] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 56.460501][ T8235] RIP: 0033:0x444f19 [ 56.464378][ T8235] 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 [ 56.483996][ T8235] RSP: 002b:00007ffcf6942a68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 56.492417][ T8235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444f19 [ 56.500403][ T8235] RDX: 0000000000000052 RSI: 0000000020000540 RDI: 0000000000000003 [ 56.508371][ T8235] RBP: 000000000000d970 R08: 00000000004002e0 R09: 00000000004002e0 [ 56.516365][ T8235] R10: 000000000000000f R11: 0000000000000246 R12: 00000000004020b0 [ 56.524352][ T8235] R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000 [ 56.533293][ T8235] Kernel Offset: disabled [ 56.537644][ T8235] Rebooting in 86400 seconds..