[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 62.262842][ T27] audit: type=1800 audit(1579708037.812:25): pid=8671 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 62.281662][ T27] audit: type=1800 audit(1579708037.812:26): pid=8671 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 62.307298][ T27] audit: type=1800 audit(1579708037.812:27): pid=8671 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 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. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.1.15' (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 syzkaller login: [ 79.466056][ T9034] ================================================================== [ 79.466087][ T9034] BUG: KASAN: slab-out-of-bounds in vc_do_resize+0xb5e/0x1af0 [ 79.466092][ T9034] Read of size 192 at addr ffff888095d34540 by task syz-executor536/9034 [ 79.466094][ T9034] [ 79.466101][ T9034] CPU: 1 PID: 9034 Comm: syz-executor536 Not tainted 5.5.0-rc7-syzkaller #0 [ 79.466105][ T9034] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 79.466107][ T9034] Call Trace: [ 79.466117][ T9034] dump_stack+0x1fb/0x318 [ 79.466126][ T9034] print_address_description+0x74/0x5c0 [ 79.466132][ T9034] ? vprintk_func+0x158/0x170 [ 79.466139][ T9034] ? printk+0x62/0x8d [ 79.466146][ T9034] ? vprintk_emit+0x2d4/0x3a0 [ 79.466153][ T9034] __kasan_report+0x149/0x1c0 [ 79.466160][ T9034] ? vc_do_resize+0xb5e/0x1af0 [ 79.466167][ T9034] kasan_report+0x26/0x50 [ 79.466172][ T9034] ? vc_do_resize+0x8a7/0x1af0 [ 79.466178][ T9034] check_memory_region+0x2b6/0x2f0 [ 79.466183][ T9034] ? vc_do_resize+0xb5e/0x1af0 [ 79.466188][ T9034] memcpy+0x28/0x60 [ 79.466195][ T9034] vc_do_resize+0xb5e/0x1af0 [ 79.466213][ T9034] ? fb_match_mode+0x5a1/0x6e0 [ 79.466220][ T9034] vc_resize+0x4f/0x60 [ 79.466226][ T9034] fbcon_modechanged+0x701/0xdf0 [ 79.466236][ T9034] fbcon_update_vcs+0x31/0x40 [ 79.466242][ T9034] fb_set_var+0x8f5/0xdc0 [ 79.466260][ T9034] do_fb_ioctl+0x55e/0x780 [ 79.466276][ T9034] fb_ioctl+0xb9/0xf0 [ 79.466280][ T9034] ? fb_write+0x580/0x580 [ 79.466288][ T9034] do_vfs_ioctl+0x6e2/0x19b0 [ 79.466294][ T9034] ? __fget+0x4a1/0x520 [ 79.466303][ T9034] ? tomoyo_file_ioctl+0x23/0x30 [ 79.466310][ T9034] ? security_file_ioctl+0xb1/0xd0 [ 79.466317][ T9034] __x64_sys_ioctl+0xe3/0x120 [ 79.466325][ T9034] do_syscall_64+0xf7/0x1c0 [ 79.466333][ T9034] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 79.466339][ T9034] RIP: 0033:0x446d49 [ 79.466345][ T9034] Code: e8 0c 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 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 79.466348][ T9034] RSP: 002b:00007fc010171db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 79.466354][ T9034] RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 0000000000446d49 [ 79.466357][ T9034] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004 [ 79.466360][ T9034] RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000 [ 79.466363][ T9034] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c [ 79.466367][ T9034] R13: 00007ffc8ab7313f R14: 00007fc0101729c0 R15: 0000000000000001 [ 79.466375][ T9034] [ 79.466378][ T9034] Allocated by task 9034: [ 79.466383][ T9034] __kasan_kmalloc+0x118/0x1c0 [ 79.466389][ T9034] kasan_kmalloc+0x9/0x10 [ 79.466396][ T9034] __kmalloc+0x254/0x340 [ 79.466401][ T9034] kzalloc+0x21/0x40 [ 79.466405][ T9034] vc_do_resize+0x2af/0x1af0 [ 79.466410][ T9034] vc_resize+0x4f/0x60 [ 79.466414][ T9034] fbcon_modechanged+0x701/0xdf0 [ 79.466418][ T9034] fbcon_update_vcs+0x31/0x40 [ 79.466422][ T9034] fb_set_var+0x8f5/0xdc0 [ 79.466426][ T9034] fbcon_resize+0x819/0x11f0 [ 79.466431][ T9034] vc_do_resize+0x478/0x1af0 [ 79.466435][ T9034] vc_resize+0x4f/0x60 [ 79.466439][ T9034] fbcon_modechanged+0x701/0xdf0 [ 79.466443][ T9034] fbcon_update_vcs+0x31/0x40 [ 79.466447][ T9034] fb_set_var+0x8f5/0xdc0 [ 79.466452][ T9034] do_fb_ioctl+0x55e/0x780 [ 79.466456][ T9034] fb_ioctl+0xb9/0xf0 [ 79.466461][ T9034] do_vfs_ioctl+0x6e2/0x19b0 [ 79.466465][ T9034] __x64_sys_ioctl+0xe3/0x120 [ 79.466470][ T9034] do_syscall_64+0xf7/0x1c0 [ 79.466475][ T9034] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 79.466477][ T9034] [ 79.466479][ T9034] Freed by task 8579: [ 79.466484][ T9034] __kasan_slab_free+0x12e/0x1e0 [ 79.466488][ T9034] kasan_slab_free+0xe/0x10 [ 79.466492][ T9034] kfree+0x10d/0x220 [ 79.466499][ T9034] load_elf_binary+0x2c82/0x36d0 [ 79.466503][ T9034] search_binary_handler+0x190/0x5e0 [ 79.466507][ T9034] __do_execve_file+0x1565/0x1cc0 [ 79.466511][ T9034] __x64_sys_execve+0x94/0xb0 [ 79.466516][ T9034] do_syscall_64+0xf7/0x1c0 [ 79.466521][ T9034] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 79.466522][ T9034] [ 79.466526][ T9034] The buggy address belongs to the object at ffff888095d34400 [ 79.466526][ T9034] which belongs to the cache kmalloc-512 of size 512 [ 79.466531][ T9034] The buggy address is located 320 bytes inside of [ 79.466531][ T9034] 512-byte region [ffff888095d34400, ffff888095d34600) [ 79.466533][ T9034] The buggy address belongs to the page: [ 79.466539][ T9034] page:ffffea0002574d00 refcount:1 mapcount:0 mapping:ffff8880aa800a80 index:0x0 [ 79.466547][ T9034] raw: 00fffe0000000200 ffffea0002741f88 ffffea0002846a48 ffff8880aa800a80 [ 79.466552][ T9034] raw: 0000000000000000 ffff888095d34000 0000000100000004 0000000000000000 [ 79.466555][ T9034] page dumped because: kasan: bad access detected [ 79.466556][ T9034] [ 79.466558][ T9034] Memory state around the buggy address: [ 79.466562][ T9034] ffff888095d34480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 79.466566][ T9034] ffff888095d34500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 79.466570][ T9034] >ffff888095d34580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 79.466572][ T9034] ^ [ 79.466576][ T9034] ffff888095d34600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 79.466580][ T9034] ffff888095d34680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 79.466582][ T9034] ================================================================== [ 79.466584][ T9034] Disabling lock debugging due to kernel taint [ 79.466588][ T9034] Kernel panic - not syncing: panic_on_warn set ... [ 79.466593][ T9034] CPU: 1 PID: 9034 Comm: syz-executor536 Tainted: G B 5.5.0-rc7-syzkaller #0 [ 79.466596][ T9034] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 79.466597][ T9034] Call Trace: [ 79.466603][ T9034] dump_stack+0x1fb/0x318 [ 79.466609][ T9034] panic+0x264/0x7a9 [ 79.466613][ T9034] ? __kasan_report+0x193/0x1c0 [ 79.466619][ T9034] ? trace_hardirqs_on+0x34/0x80 [ 79.466627][ T9034] __kasan_report+0x1b9/0x1c0 [ 79.466636][ T9034] ? vc_do_resize+0xb5e/0x1af0 [ 79.466645][ T9034] kasan_report+0x26/0x50 [ 79.466653][ T9034] ? vc_do_resize+0x8a7/0x1af0 [ 79.466662][ T9034] check_memory_region+0x2b6/0x2f0 [ 79.466670][ T9034] ? vc_do_resize+0xb5e/0x1af0 [ 79.466677][ T9034] memcpy+0x28/0x60 [ 79.466686][ T9034] vc_do_resize+0xb5e/0x1af0 [ 79.466705][ T9034] ? fb_match_mode+0x5a1/0x6e0 [ 79.466715][ T9034] vc_resize+0x4f/0x60 [ 79.466723][ T9034] fbcon_modechanged+0x701/0xdf0 [ 79.466736][ T9034] fbcon_update_vcs+0x31/0x40 [ 79.466745][ T9034] fb_set_var+0x8f5/0xdc0 [ 79.466767][ T9034] do_fb_ioctl+0x55e/0x780 [ 79.466785][ T9034] fb_ioctl+0xb9/0xf0 [ 79.466793][ T9034] ? fb_write+0x580/0x580 [ 79.466803][ T9034] do_vfs_ioctl+0x6e2/0x19b0 [ 79.466811][ T9034] ? __fget+0x4a1/0x520 [ 79.466822][ T9034] ? tomoyo_file_ioctl+0x23/0x30 [ 79.466833][ T9034] ? security_file_ioctl+0xb1/0xd0 [ 79.466844][ T9034] __x64_sys_ioctl+0xe3/0x120 [ 79.466854][ T9034] do_syscall_64+0xf7/0x1c0 [ 79.466865][ T9034] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 79.466872][ T9034] RIP: 0033:0x446d49 [ 79.466880][ T9034] Code: e8 0c 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 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 79.466891][ T9034] RSP: 002b:00007fc010171db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 79.466898][ T9034] RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 0000000000446d49 [ 79.466901][ T9034] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004 [ 79.466903][ T9034] RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000 [ 79.466906][ T9034] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c [ 79.466909][ T9034] R13: 00007ffc8ab7313f R14: 00007fc0101729c0 R15: 0000000000000001 [ 79.468418][ T9034] Kernel Offset: disabled