====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/27430 is trying to acquire lock: 000000004a17188b (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 but task is already holding lock: 000000009cda78c7 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2779 [inline] 000000009cda78c7 (sb_writers#3){.+.+}, at: do_sendfile+0x97d/0xc30 fs/read_write.c:1446 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (sb_writers#3){.+.+}: sb_start_write include/linux/fs.h:1579 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:360 ovl_create_object+0x96/0x290 fs/overlayfs/dir.c:602 lookup_open+0x893/0x1a20 fs/namei.c:3235 do_last fs/namei.c:3327 [inline] path_openat+0x1094/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&ovl_i_mutex_dir_key[depth]){++++}: 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 -> #1 (&sig->cred_guard_mutex){+.+.}: 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 __vfs_read+0xf7/0x750 fs/read_write.c:416 vfs_read+0x194/0x3c0 fs/read_write.c:452 ksys_read+0x12b/0x2a0 fs/read_write.c:579 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&p->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:937 [inline] __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078 seq_read+0x6b/0x11c0 fs/seq_file.c:164 proc_reg_read+0x1bd/0x2d0 fs/proc/inode.c:231 audit: type=1800 audit(1665059070.007:360): pid=27442 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="bus" dev="sda1" ino=15250 res=0 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 other info that might help us debug this: Chain exists of: &p->lock --> &ovl_i_mutex_dir_key[depth] --> sb_writers#3 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_writers#3); lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#3); lock(&p->lock); *** DEADLOCK *** 1 lock held by syz-executor.4/27430: #0: 000000009cda78c7 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2779 [inline] #0: 000000009cda78c7 (sb_writers#3){.+.+}, at: do_sendfile+0x97d/0xc30 fs/read_write.c:1446 stack backtrace: CPU: 1 PID: 27430 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 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 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 RIP: 0033:0x7f9766fe55a9 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9765938168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f9767107050 RCX: 00007f9766fe55a9 RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000005 RBP: 00007f9767040580 R08: 0000000000000000 R09: 0000000000000000 9pnet: Insufficient options for proto=fd R10: 4000000000010046 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffc757cd0f R14: 00007f9765938300 R15: 0000000000022000 bridge0: port 3(erspan0) entered blocking state bridge0: port 3(erspan0) entered disabled state 9pnet: Insufficient options for proto=fd device erspan0 entered promiscuous mode bridge0: port 3(erspan0) entered blocking state bridge0: port 3(erspan0) entered forwarding state 9pnet: Insufficient options for proto=fd bridge0: port 3(erspan0) entered blocking state bridge0: port 3(erspan0) entered disabled state device erspan0 entered promiscuous mode bridge0: port 3(erspan0) entered blocking state bridge0: port 3(erspan0) entered forwarding state bridge0: port 3(erspan0) entered blocking state bridge0: port 3(erspan0) entered disabled state device erspan0 entered promiscuous mode bridge0: port 3(erspan0) entered blocking state bridge0: port 3(erspan0) entered forwarding state 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000c2ceb1a0 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000006dc61e9d FS-Cache: O-key=[10] '34323934393932353533' FS-Cache: N-cookie c=00000000956e7453 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=0000000064963700 FS-Cache: N-key=[10] '34323934393932353533' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000cd258101 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=00000000e9708636 FS-Cache: O-key=[10] '34323934393932353734' FS-Cache: N-cookie c=00000000be5f5200 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=0000000030600da0 FS-Cache: N-key=[10] '34323934393932353734' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=000000006cb0b189 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=00000000f8161075 FS-Cache: O-key=[10] '34323934393932363033' FS-Cache: N-cookie c=00000000ceb8d147 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] 9pnet: Insufficient options for proto=fd FS-Cache: N-cookie d=000000007a14ba46 n=00000000db6c78b3 FS-Cache: N-key=[10] '34323934393932363033' 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000810a240f [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=00000000159c8003 FS-Cache: O-key=[10] '34323934393932373033' FS-Cache: N-cookie c=00000000fe4e5fc8 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=00000000985224b5 FS-Cache: N-key=[10] '34323934393932373033' overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000b67c830c [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000003bb71556 FS-Cache: O-key=[10] '34323934393932373330' FS-Cache: N-cookie c=00000000c3778cb6 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=000000000a52bccf FS-Cache: N-key=[10] '34323934393932373330' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=000000001ba797f1 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000007de0b2b2 FS-Cache: O-key=[10] '34323934393932373534' FS-Cache: N-cookie c=00000000bb6b9929 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=00000000f2c75ee1 FS-Cache: N-key=[10] '34323934393932373534' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=000000003e4048b9 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=00000000e5868178 FS-Cache: O-key=[10] '34323934393932373736' FS-Cache: N-cookie c=000000002893bdeb [p=00000000dcf1a6a9 fl=2 nc=0 na=1] overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: N-cookie d=000000007a14ba46 n=0000000073068cd2 FS-Cache: N-key=[10] '34323934393932373736' overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=000000004bbe97bc [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000005f2b9927 9pnet: Insufficient options for proto=fd FS-Cache: O-key=[10] '34323934393932383538' FS-Cache: N-cookie c=000000002c1aeed3 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=00000000ec39abde FS-Cache: N-key=[10] '34323934393932383538' overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000a1d0a2ac [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=00000000fe01ab73 FS-Cache: O-key=[10] '34323934393932393038' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: N-cookie c=0000000053550712 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=00000000261e3bad FS-Cache: N-key=[10] '34323934393932393038' 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value 9pnet: Insufficient options for proto=fd overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=000000007338bb28 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000000cb6f9bd FS-Cache: O-key=[10] '34323934393932393339' FS-Cache: N-cookie c=000000000a8d761d [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=000000004ce720f6 FS-Cache: N-key=[10] '34323934393932393339' overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=0000000013e8888a [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000007cb96c03 FS-Cache: O-key=[10] '34323934393932393632' FS-Cache: N-cookie c=0000000038b57471 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=00000000aab9017a FS-Cache: N-key=[10] '34323934393932393632' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000844597be [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=000000008455e3c3 FS-Cache: O-key=[10] '34323934393932393931' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: N-cookie c=00000000978237e0 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=000000008c70eae3 FS-Cache: N-key=[10] '34323934393932393931' overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=000000009794fe0d [p=00000000dcf1a6a9 fl=222 nc=0 na=1] FS-Cache: O-cookie d=000000007a14ba46 n=00000000e235e102 FS-Cache: O-key=[10] '34323934393933303135' FS-Cache: N-cookie c=00000000670aa3ad [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=00000000adc63d97 FS-Cache: N-key=[10] '34323934393933303135' overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: Duplicate cookie detected FS-Cache: O-cookie c=00000000d8118972 [p=00000000dcf1a6a9 fl=222 nc=0 na=1] overlayfs: unrecognized mount option "obj_type=fowner" or missing value FS-Cache: O-cookie d=000000007a14ba46 n=000000009ea51e35 FS-Cache: O-key=[10] '34323934393933303432' FS-Cache: N-cookie c=0000000001812fa7 [p=00000000dcf1a6a9 fl=2 nc=0 na=1] FS-Cache: N-cookie d=000000007a14ba46 n=000000009be1cc3c FS-Cache: N-key=[10] '34323934393933303432' overlayfs: unrecognized mount option "obj_type=fowner" or missing value overlayfs: unrecognized mount option "obj_type=fowner" or missing value