Buffer I/O error on dev loop4p4, logical block 28656, async page read IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready ------------------------------------------------------ syz-executor.0/30180 is trying to acquire lock: 00000000b9fedb03 (&sig->cred_guard_mutex){+.+.}, at: do_io_accounting fs/proc/base.c:2750 [inline] 00000000b9fedb03 (&sig->cred_guard_mutex){+.+.}, at: proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2793 but task is already holding lock: MTD: Attempt to mount non-MTD device "/dev/loop4" 00000000a32c0037 (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&p->lock){+.+.}: seq_read+0x6b/0x11c0 fs/seq_file.c:164 proc_reg_read+0x1bd/0x2d0 fs/proc/inode.c:231 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 kernel_readv fs/splice.c:362 [inline] default_file_splice_read+0x457/0xa00 fs/splice.c:417 do_splice_to+0x10e/0x160 fs/splice.c:881 splice_direct_to_actor+0x2b9/0x8d0 fs/splice.c:959 do_splice_direct+0x1a7/0x270 fs/splice.c:1068 do_sendfile+0x550/0xc30 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (sb_writers#3){.+.+}: sb_start_write include/linux/fs.h:1579 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:360 ovl_do_remove+0xf0/0xdb0 fs/overlayfs/dir.c:845 vfs_rmdir.part.0+0x10f/0x3d0 fs/namei.c:3882 vfs_rmdir fs/namei.c:3868 [inline] do_rmdir+0x3fd/0x490 fs/namei.c:3943 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (&ovl_i_mutex_dir_key[depth]#2){++++}: inode_lock_shared include/linux/fs.h:758 [inline] do_last fs/namei.c:3326 [inline] path_openat+0x17ec/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_open_execat+0x11d/0x5b0 fs/exec.c:853 __do_execve_file+0x1a8b/0x2360 fs/exec.c:1770 do_execveat_common fs/exec.c:1879 [inline] do_execve+0x35/0x50 fs/exec.c:1896 __do_sys_execve fs/exec.c:1977 [inline] __se_sys_execve fs/exec.c:1972 [inline] __x64_sys_execve+0x7c/0xa0 fs/exec.c:1972 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&sig->cred_guard_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:937 [inline] __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078 do_io_accounting fs/proc/base.c:2750 [inline] proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2793 proc_single_show+0xeb/0x170 fs/proc/base.c:755 seq_read+0x4e0/0x11c0 fs/seq_file.c:232 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 do_preadv fs/read_write.c:1071 [inline] __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1116 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: &sig->cred_guard_mutex --> sb_writers#3 --> &p->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->lock); lock(sb_writers#3); lock(&p->lock); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 1 lock held by syz-executor.0/30180: #0: 00000000a32c0037 (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 stack backtrace: CPU: 1 PID: 30180 Comm: syz-executor.0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 __mutex_lock_common kernel/locking/mutex.c:937 [inline] __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078 do_io_accounting fs/proc/base.c:2750 [inline] proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2793 proc_single_show+0xeb/0x170 fs/proc/base.c:755 seq_read+0x4e0/0x11c0 fs/seq_file.c:232 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 do_preadv fs/read_write.c:1071 [inline] __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1116 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f88e7d99ae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f88e6d0f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 device vxlan0 entered promiscuous mode RAX: ffffffffffffffda RBX: 00007f88e7eacf60 RCX: 00007f88e7d99ae9 RDX: 0000000000000332 RSI: 00000000200017c0 RDI: 0000000000000004 RBP: 00007f88e7df3ff7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe639d6a6f R14: 00007f88e6d0f300 R15: 0000000000022000 MTD: Attempt to mount non-MTD device "/dev/loop4" Can't find ip_set type bitmap:ip,mac overlayfs: unrecognized mount option "°Ìã8É h¥¬mlowerdir=8©ive0" or missing value overlayfs: './file0' not a directory overlayfs: unrecognized mount option "°Ìã8É h¥¬mlowerdir=8©ive0" or missing value overlayfs: './file0' not a directory print_req_error: 67 callbacks suppressed print_req_error: I/O error, dev loop4, sector 229217 print_req_error: I/O error, dev loop4, sector 229217 buffer_io_error: 53 callbacks suppressed Buffer I/O error on dev loop4p3, logical block 228992, async page read print_req_error: I/O error, dev loop4, sector 229218 Buffer I/O error on dev loop4p3, logical block 228993, async page read print_req_error: I/O error, dev loop4, sector 229219 Buffer I/O error on dev loop4p3, logical block 228994, async page read print_req_error: I/O error, dev loop4, sector 229220 Buffer I/O error on dev loop4p3, logical block 228995, async page read print_req_error: I/O error, dev loop4, sector 229221 Buffer I/O error on dev loop4p3, logical block 228996, async page read print_req_error: I/O error, dev loop4, sector 229222 Buffer I/O error on dev loop4p3, logical block 228997, async page read print_req_error: I/O error, dev loop4, sector 229223 Buffer I/O error on dev loop4p3, logical block 228998, async page read print_req_error: I/O error, dev loop4, sector 229224 Buffer I/O error on dev loop4p3, logical block 228999, async page read print_req_error: I/O error, dev loop4, sector 229248 Buffer I/O error on dev loop4p4, logical block 28656, async page read Buffer I/O error on dev loop4p3, logical block 228992, async page read kauditd_printk_skb: 2 callbacks suppressed audit: type=1800 audit(1638726139.515:348): pid=30331 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="bus" dev="sda1" ino=15198 res=0 bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state ax25_connect(): syz-executor.0 uses autobind, please contact jreuter@yaina.de IPVS: ftp: loaded support on port[0] = 21 A link change request failed with some changes committed already. Interface gretap0 may have been left with an inconsistent configuration, please check. IPVS: ftp: loaded support on port[0] = 21 syz-executor.0 (30383) used greatest stack depth: 22216 bytes left nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. x_tables: ip6_tables: TCPMSS target: only valid for protocol 6 x_tables: ip6_tables: TCPMSS target: only valid for protocol 6