UBIFS error (pid: 13820): cannot open "(null)", error -22 overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.3/13828 is trying to acquire lock: 00000000b7441a6b (&sig->cred_guard_mutex){+.+.}, at: lock_trace fs/proc/base.c:402 [inline] 00000000b7441a6b (&sig->cred_guard_mutex){+.+.}, at: proc_pid_personality+0x4a/0x170 fs/proc/base.c:2938 but task is already holding lock: 00000000eb158194 (&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 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_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 -> #1 (&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 -> #0 (&sig->cred_guard_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:937 [inline] __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078 lock_trace fs/proc/base.c:402 [inline] proc_pid_personality+0x4a/0x170 fs/proc/base.c:2938 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 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: &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 *** 2 locks held by syz-executor.3/13828: #0: 0000000018d5d84f (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2779 [inline] #0: 0000000018d5d84f (sb_writers#3){.+.+}, at: do_sendfile+0x97d/0xc30 fs/read_write.c:1446 #1: 00000000eb158194 (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 stack backtrace: CPU: 0 PID: 13828 Comm: syz-executor.3 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 lock_trace fs/proc/base.c:402 [inline] proc_pid_personality+0x4a/0x170 fs/proc/base.c:2938 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 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: 0033:0x7f63c2336049 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:00007f63c0cab168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f63c2448f60 RCX: 00007f63c2336049 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000010 RBP: 00007f63c239008d R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000f6c4 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd53f3206f R14: 00007f63c0cab300 R15: 0000000000022000 kauditd_printk_skb: 8 callbacks suppressed audit: type=1800 audit(1648908702.322:134): pid=13861 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=3 res=0 overlayfs: filesystem on './bus' not supported as upperdir audit: type=1800 audit(1648908702.662:135): pid=13936 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=4 res=0 attempt to access beyond end of device loop1: rw=2049, want=48, limit=16 audit: type=1800 audit(1648908702.942:136): pid=14003 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=5 res=0 audit: type=1800 audit(1648908703.243:137): pid=14042 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=6 res=0 attempt to access beyond end of device loop2: rw=2049, want=128, limit=16 audit: type=1800 audit(1648908705.653:138): pid=14094 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=7 res=0 audit: type=1800 audit(1648908705.703:139): pid=14103 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=8 res=0 attempt to access beyond end of device attempt to access beyond end of device loop2: rw=2049, want=48, limit=16 loop1: rw=2049, want=56, limit=16 audit: type=1800 audit(1648908705.733:140): pid=14106 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="file0" dev="loop3" ino=9 res=0 attempt to access beyond end of device loop3: rw=2049, want=40, limit=16 audit: type=1800 audit(1648908706.223:141): pid=14176 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="file0" dev="loop3" ino=10 res=0 attempt to access beyond end of device attempt to access beyond end of device loop3: rw=2049, want=56, limit=16 audit: type=1800 audit(1648908706.253:142): pid=14181 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=11 res=0 loop2: rw=2049, want=40, limit=16 audit: type=1800 audit(1648908706.383:143): pid=14188 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=12 res=0 attempt to access beyond end of device loop1: rw=2049, want=72, limit=16 audit: type=1800 audit(1648908708.783:144): pid=14214 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=13 res=0 attempt to access beyond end of device loop2: rw=2049, want=40, limit=16 audit: type=1800 audit(1648908708.873:145): pid=14219 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=14 res=0 attempt to access beyond end of device loop1: rw=2049, want=128, limit=16 attempt to access beyond end of device audit: type=1800 audit(1648908708.903:146): pid=14222 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="loop5" ino=15 res=0 loop5: rw=2049, want=128, limit=16 audit: type=1800 audit(1648908709.233:147): pid=14251 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=16 res=0 audit: type=1800 audit(1648908709.493:148): pid=14270 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=17 res=0 attempt to access beyond end of device loop2: rw=2049, want=128, limit=16 audit: type=1800 audit(1648908709.583:149): pid=14276 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="loop5" ino=18 res=0 audit: type=1800 audit(1648908709.823:150): pid=14302 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=19 res=0 attempt to access beyond end of device loop1: rw=2049, want=40, limit=16 audit: type=1800 audit(1648908709.883:151): pid=14307 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="file0" dev="loop2" ino=20 res=0 audit: type=1800 audit(1648908709.913:152): pid=14315 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="loop5" ino=21 res=0 attempt to access beyond end of device loop2: rw=2049, want=128, limit=16 audit: type=1800 audit(1648908710.323:153): pid=14339 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="loop5" ino=22 res=0 attempt to access beyond end of device loop5: rw=2049, want=40, limit=16 attempt to access beyond end of device loop5: rw=2049, want=128, limit=16 attempt to access beyond end of device loop5: rw=2049, want=128, limit=16