[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.207' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 34.199686] audit: type=1400 audit(1594550993.026:8): avc: denied { execmem } for pid=6332 comm="syz-executor873" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 34.287976] ================================================================== [ 34.288000] BUG: KASAN: slab-out-of-bounds in bit_putcs+0xa8a/0xc00 [ 34.288005] Read of size 1 at addr ffff88809a2286f0 by task syz-executor873/6332 [ 34.288006] [ 34.288012] CPU: 1 PID: 6332 Comm: syz-executor873 Not tainted 4.14.184-syzkaller #0 [ 34.288015] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.288017] Call Trace: [ 34.288026] dump_stack+0x1b2/0x283 [ 34.288031] ? bit_putcs+0xa8a/0xc00 [ 34.288039] print_address_description.cold+0x54/0x1dc [ 34.288044] ? bit_putcs+0xa8a/0xc00 [ 34.288048] kasan_report.cold+0xa9/0x2b9 [ 34.288053] bit_putcs+0xa8a/0xc00 [ 34.288064] ? bit_cursor+0x1660/0x1660 [ 34.288072] ? fb_get_color_depth+0x5a/0x70 [ 34.288078] ? bit_cursor+0x1660/0x1660 [ 34.288081] fbcon_putcs+0x3bb/0x480 [ 34.288090] do_update_region+0x34b/0x5b0 [ 34.288096] ? con_get_trans_old+0x200/0x200 [ 34.288104] redraw_screen+0x562/0x760 [ 34.288110] ? set_palette+0x130/0x130 [ 34.288116] vc_do_resize+0xbe0/0xde0 [ 34.288124] ? vc_init+0x430/0x430 [ 34.288133] vt_ioctl+0x1a64/0x1f20 [ 34.288138] ? complete_change_console+0x350/0x350 [ 34.288143] ? avc_ss_reset+0x100/0x100 [ 34.288149] ? kasan_slab_free+0x119/0x190 [ 34.288153] ? kasan_slab_free+0xaf/0x190 [ 34.288157] ? kmem_cache_free+0x7c/0x2b0 [ 34.288162] ? putname+0xcd/0x110 [ 34.288166] ? do_sys_open+0x233/0x3e0 [ 34.288171] ? do_syscall_64+0x1d5/0x640 [ 34.288177] ? entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 34.288182] ? path_mountpoint+0x960/0x960 [ 34.288185] ? tty_jobctrl_ioctl+0x3b/0xbf0 [ 34.288190] ? complete_change_console+0x350/0x350 [ 34.288196] tty_ioctl+0x6c9/0x1220 [ 34.288200] ? tty_vhangup+0x30/0x30 [ 34.288207] ? lock_acquire+0x170/0x3f0 [ 34.288211] ? lock_downgrade+0x6e0/0x6e0 [ 34.288220] ? tty_vhangup+0x30/0x30 [ 34.288225] do_vfs_ioctl+0x75a/0xfe0 [ 34.288232] ? selinux_parse_skb.constprop.0+0x16c0/0x16c0 [ 34.288237] ? ioctl_preallocate+0x1a0/0x1a0 [ 34.288242] ? rcu_read_lock_sched_held+0x10a/0x130 [ 34.288246] ? kmem_cache_free+0x23a/0x2b0 [ 34.288251] ? putname+0xcd/0x110 [ 34.288259] ? security_file_ioctl+0x76/0xb0 [ 34.288263] ? security_file_ioctl+0x83/0xb0 [ 34.288268] SyS_ioctl+0x7f/0xb0 [ 34.288271] ? do_vfs_ioctl+0xfe0/0xfe0 [ 34.288276] do_syscall_64+0x1d5/0x640 [ 34.288284] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 34.288288] RIP: 0033:0x4403a9 [ 34.288291] RSP: 002b:00007fff7eabedd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 34.288296] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004403a9 [ 34.288299] RDX: 0000000020000080 RSI: 000000000000560a RDI: 0000000000000004 [ 34.288302] RBP: 00000000006ca018 R08: 000000000000000d R09: 00000000004002c8 [ 34.288304] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401c10 [ 34.288307] R13: 0000000000401ca0 R14: 0000000000000000 R15: 0000000000000000 [ 34.288314] [ 34.288316] Allocated by task 6332: [ 34.288321] kasan_kmalloc.part.0+0x4f/0xd0 [ 34.288324] __kmalloc+0x15a/0x400 [ 34.288328] fbcon_set_font+0x2f8/0x7c0 [ 34.288332] con_font_op+0xb73/0xf70 [ 34.288335] vt_ioctl+0x736/0x1f20 [ 34.288339] tty_ioctl+0x6c9/0x1220 [ 34.288342] do_vfs_ioctl+0x75a/0xfe0 [ 34.288345] SyS_ioctl+0x7f/0xb0 [ 34.288348] do_syscall_64+0x1d5/0x640 [ 34.288352] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 34.288353] [ 34.288355] Freed by task 4592: [ 34.288359] kasan_slab_free+0xaf/0x190 [ 34.288363] kfree+0xcb/0x260 [ 34.288367] skb_free_head+0x83/0xa0 [ 34.288371] skb_release_data+0x57e/0x7d0 [ 34.288375] skb_release_all+0x46/0x60 [ 34.288378] kfree_skb+0xae/0x340 [ 34.288383] netlink_unicast+0x563/0x610 [ 34.288387] netlink_sendmsg+0x64a/0xbb0 [ 34.288392] sock_sendmsg+0xb5/0x100 [ 34.288395] ___sys_sendmsg+0x70a/0x840 [ 34.288399] __sys_sendmsg+0xa3/0x120 [ 34.288402] SyS_sendmsg+0x27/0x40 [ 34.288406] do_syscall_64+0x1d5/0x640 [ 34.288410] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 34.288411] [ 34.288415] The buggy address belongs to the object at ffff88809a2284c0 [ 34.288415] which belongs to the cache kmalloc-1024 of size 1024 [ 34.288418] The buggy address is located 560 bytes inside of [ 34.288418] 1024-byte region [ffff88809a2284c0, ffff88809a2288c0) [ 34.288420] The buggy address belongs to the page: [ 34.288424] page:ffffea0002688a00 count:1 mapcount:0 mapping:ffff88809a228040 index:0x0 compound_mapcount: 0 [ 34.288430] flags: 0xfffe0000008100(slab|head) [ 34.288437] raw: 00fffe0000008100 ffff88809a228040 0000000000000000 0000000100000007 [ 34.288441] raw: ffffea00026d8ba0 ffffea00025f31a0 ffff8880aa800ac0 0000000000000000 [ 34.288443] page dumped because: kasan: bad access detected [ 34.288444] [ 34.288446] Memory state around the buggy address: [ 34.288450] ffff88809a228580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 34.288453] ffff88809a228600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 34.288456] >ffff88809a228680: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc [ 34.288458] ^ [ 34.288461] ffff88809a228700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 34.288464] ffff88809a228780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 34.288466] ================================================================== [ 34.288467] Disabling lock debugging due to kernel taint [ 34.288470] Kernel panic - not syncing: panic_on_warn set ... [ 34.288470] [ 34.288474] CPU: 1 PID: 6332 Comm: syz-executor873 Tainted: G B 4.14.184-syzkaller #0 [ 34.288476] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.288477] Call Trace: [ 34.288482] dump_stack+0x1b2/0x283 [ 34.288489] panic+0x1f9/0x42d [ 34.288493] ? add_taint.cold+0x16/0x16 [ 34.288497] ? lock_downgrade+0x6e0/0x6e0 [ 34.288502] ? bit_putcs+0xa8a/0xc00 [ 34.288506] kasan_end_report+0x43/0x49 [ 34.288510] kasan_report.cold+0x12f/0x2b9 [ 34.288515] bit_putcs+0xa8a/0xc00 [ 34.288522] ? bit_cursor+0x1660/0x1660 [ 34.288527] ? fb_get_color_depth+0x5a/0x70 [ 34.288532] ? bit_cursor+0x1660/0x1660 [ 34.288535] fbcon_putcs+0x3bb/0x480 [ 34.288540] do_update_region+0x34b/0x5b0 [ 34.288545] ? con_get_trans_old+0x200/0x200 [ 34.288551] redraw_screen+0x562/0x760 [ 34.288555] ? set_palette+0x130/0x130 [ 34.288560] vc_do_resize+0xbe0/0xde0 [ 34.288565] ? vc_init+0x430/0x430 [ 34.288571] vt_ioctl+0x1a64/0x1f20 [ 34.288575] ? complete_change_console+0x350/0x350 [ 34.288579] ? avc_ss_reset+0x100/0x100 [ 34.288583] ? kasan_slab_free+0x119/0x190 [ 34.288587] ? kasan_slab_free+0xaf/0x190 [ 34.288591] ? kmem_cache_free+0x7c/0x2b0 [ 34.288594] ? putname+0xcd/0x110 [ 34.288597] ? do_sys_open+0x233/0x3e0 [ 34.288601] ? do_syscall_64+0x1d5/0x640 [ 34.288604] ? entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 34.288608] ? path_mountpoint+0x960/0x960 [ 34.288611] ? tty_jobctrl_ioctl+0x3b/0xbf0 [ 34.288615] ? complete_change_console+0x350/0x350 [ 34.288619] tty_ioctl+0x6c9/0x1220 [ 34.288623] ? tty_vhangup+0x30/0x30 [ 34.288627] ? lock_acquire+0x170/0x3f0 [ 34.288630] ? lock_downgrade+0x6e0/0x6e0 [ 34.288637] ? tty_vhangup+0x30/0x30 [ 34.288640] do_vfs_ioctl+0x75a/0xfe0 [ 34.288644] ? selinux_parse_skb.constprop.0+0x16c0/0x16c0 [ 34.288648] ? ioctl_preallocate+0x1a0/0x1a0 [ 34.288652] ? rcu_read_lock_sched_held+0x10a/0x130 [ 34.288656] ? kmem_cache_free+0x23a/0x2b0 [ 34.288659] ? putname+0xcd/0x110 [ 34.288664] ? security_file_ioctl+0x76/0xb0 [ 34.288668] ? security_file_ioctl+0x83/0xb0 [ 34.288672] SyS_ioctl+0x7f/0xb0 [ 34.288675] ? do_vfs_ioctl+0xfe0/0xfe0 [ 34.288679] do_syscall_64+0x1d5/0x640 [ 34.288691] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 34.288694] RIP: 0033:0x4403a9 [ 34.288696] RSP: 002b:00007fff7eabedd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 34.288700] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004403a9 [ 34.288702] RDX: 0000000020000080 RSI: 000000000000560a RDI: 0000000000000004 [ 34.288704] RBP: 00000000006ca018 R08: 000000000000000d R09: 00000000004002c8 [ 34.288706] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401c10 [ 34.288708] R13: 0000000000401ca0 R14: 0000000000000000 R15: 0000000000000000 [ 34.289743] Kernel Offset: disabled [ 35.075600] Rebooting in 86400 seconds..