overlayfs: missing 'workdir' ================================================================== BUG: KASAN: use-after-free in __fb_pad_aligned_buffer include/linux/fb.h:663 [inline] BUG: KASAN: use-after-free in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] BUG: KASAN: use-after-free in bit_putcs+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185 Read of size 1 at addr ffff88805c2a0b5a by task syz-executor.5/24024 CPU: 1 PID: 24024 Comm: syz-executor.5 Not tainted 4.14.194-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427 __fb_pad_aligned_buffer include/linux/fb.h:663 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] bit_putcs+0xab7/0xc30 drivers/video/fbdev/core/bitblit.c:185 fbcon_putcs+0x2fe/0x480 drivers/video/fbdev/core/fbcon.c:1301 do_update_region+0x34b/0x5b0 drivers/tty/vt/vt.c:373 update_region+0xd7/0x110 drivers/tty/vt/vt.c:391 vcs_write+0x3b9/0xb40 drivers/tty/vt/vc_screen.c:549 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45d579 RSP: 002b:00007f7919076c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000000381c0 RCX: 000000000045d579 RDX: 0000000000000018 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007fff1d0fdd0f R14: 00007f79190779c0 R15: 000000000118cf4c Allocated by task 23348: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] kzalloc include/linux/slab.h:661 [inline] __register_sysctl_table+0xfd/0xf90 fs/proc/proc_sysctl.c:1304 __devinet_sysctl_register+0x13d/0x250 net/ipv4/devinet.c:2314 devinet_sysctl_register+0x134/0x1f0 net/ipv4/devinet.c:2354 inetdev_init+0x202/0x410 net/ipv4/devinet.c:262 inetdev_event+0x8a5/0x1065 net/ipv4/devinet.c:1462 notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1667 [inline] call_netdevice_notifiers net/core/dev.c:1683 [inline] register_netdevice+0xb98/0xe40 net/core/dev.c:7690 veth_newlink+0x3a6/0x890 drivers/net/veth.c:416 rtnl_newlink+0xf88/0x1830 net/core/rtnetlink.c:2728 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 6369: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 __rcu_reclaim kernel/rcu/rcu.h:190 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x88b/0x1180 kernel/rcu/tree.c:2946 __do_softirq+0x254/0xa1d kernel/softirq.c:288 The buggy address belongs to the object at ffff88805c2a0b00 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 90 bytes inside of 2048-byte region [ffff88805c2a0b00, ffff88805c2a1300) The buggy address belongs to the page: page:ffffea000170a800 count:1 mapcount:0 mapping:ffff88805c2a0280 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffff88805c2a0280 0000000000000000 0000000100000003 raw: ffffea000157d620 ffffea0002992c20 ffff88812fe52c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805c2a0a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805c2a0a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805c2a0b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805c2a0b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805c2a0c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================