audit: type=1804 audit(1642265564.780:8921): pid=4263 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir132504867/syzkaller.fopFX0/1160/bus" dev="sda1" ino=14590 res=1 ====================================================== audit: type=1804 audit(1642265564.830:8922): pid=4273 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir410969335/syzkaller.qxsIE6/1390/bus" dev="sda1" ino=14306 res=1 WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/4269 is trying to acquire lock: 000000001d0ee99c (&ovl_i_mutex_dir_key[depth]){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] 000000001d0ee99c (&ovl_i_mutex_dir_key[depth]){++++}, at: lookup_slow fs/namei.c:1688 [inline] 000000001d0ee99c (&ovl_i_mutex_dir_key[depth]){++++}, at: walk_component+0x798/0xda0 fs/namei.c:1811 but task is already holding lock: 0000000042ffe2d8 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1419 [inline] 0000000042ffe2d8 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x38c/0x2360 fs/exec.c:1762 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&sig->cred_guard_mutex){+.+.}: lock_trace fs/proc/base.c:402 [inline] proc_pid_stack+0x160/0x350 fs/proc/base.c:452 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_pread64 fs/read_write.c:627 [inline] __do_sys_pread64 fs/read_write.c:637 [inline] __se_sys_pread64 fs/read_write.c:634 [inline] __x64_sys_pread64+0x1f7/0x250 fs/read_write.c:634 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #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#7){.+.+}: 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]#2){++++}: inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow fs/namei.c:1688 [inline] lookup_one_len_unlocked+0x111/0x140 fs/namei.c:2573 ovl_lookup_single+0x60/0x920 fs/overlayfs/namei.c:206 ovl_lookup_layer+0x3bd/0x440 fs/overlayfs/namei.c:292 ovl_lookup+0x729/0x1a00 fs/overlayfs/namei.c:903 __lookup_slow+0x246/0x4a0 fs/namei.c:1672 lookup_slow fs/namei.c:1689 [inline] walk_component+0x7ac/0xda0 fs/namei.c:1811 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_parentat+0x51/0x140 fs/namei.c:2367 filename_parentat+0x198/0x590 fs/namei.c:2389 do_renameat2+0x193/0xc70 fs/namei.c:4547 __do_sys_rename fs/namei.c:4675 [inline] __se_sys_rename fs/namei.c:4673 [inline] __x64_sys_rename+0x5d/0x80 fs/namei.c:4673 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&ovl_i_mutex_dir_key[depth]){++++}: down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow fs/namei.c:1688 [inline] walk_component+0x798/0xda0 fs/namei.c:1811 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1db/0x2df0 fs/namei.c:3536 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 other info that might help us debug this: Chain exists of: &ovl_i_mutex_dir_key[depth] --> &p->lock --> &sig->cred_guard_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sig->cred_guard_mutex); lock(&p->lock); lock(&sig->cred_guard_mutex); lock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 1 lock held by syz-executor.2/4269: #0: 0000000042ffe2d8 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1419 [inline] #0: 0000000042ffe2d8 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x38c/0x2360 fs/exec.c:1762 stack backtrace: CPU: 1 PID: 4269 Comm: syz-executor.2 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 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow fs/namei.c:1688 [inline] walk_component+0x798/0xda0 fs/namei.c:1811 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1db/0x2df0 fs/namei.c:3536 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 RIP: 0033:0x7f57b1e49fe9 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:00007f57b07bf168 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00007f57b1f5cf60 RCX: 00007f57b1e49fe9 RDX: 0000000020000780 RSI: 0000000020000680 RDI: 0000000020000000 RBP: 00007f57b1ea408d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe35848caf R14: 00007f57b07bf300 R15: 0000000000022000 audit: type=1804 audit(1642265564.880:8923): pid=4284 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir893734590/syzkaller.qGpK5l/1579/bus" dev="sda1" ino=14730 res=1 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN audit: type=1804 audit(1642265564.970:8924): pid=4286 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir132504867/syzkaller.fopFX0/1161/bus" dev="sda1" ino=14777 res=1 audit: type=1804 audit(1642265565.701:8925): pid=4287 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir410969335/syzkaller.qxsIE6/1391/bus" dev="sda1" ino=13877 res=1 audit: type=1804 audit(1642265565.771:8926): pid=4310 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir893734590/syzkaller.qGpK5l/1580/bus" dev="sda1" ino=14683 res=1 audit: type=1804 audit(1642265565.831:8927): pid=4305 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir132504867/syzkaller.fopFX0/1162/bus" dev="sda1" ino=14306 res=1 audit: type=1804 audit(1642265565.871:8928): pid=4311 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir410969335/syzkaller.qxsIE6/1392/bus" dev="sda1" ino=14573 res=1 kvm: vcpu 0: requested 128 ns lapic timer period limited to 200000 ns overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. audit: type=1804 audit(1642265566.321:8929): pid=4341 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir263510277/syzkaller.8t1iQ2/1160/bus" dev="sda1" ino=14509 res=1 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: unrecognized mount option "w rkdir=./fi" or missing value ieee802154 phy0 wpan0: encryption failed: -22 ieee802154 phy1 wpan1: encryption failed: -22 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: unrecognized mount option "w rkdir=./fi" or missing value vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "w '=>ǣhorkdkC1/file1" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "w '=>ǣhorkdkC1/file1" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "w '=>ǣhorkdkC1/file1" or missing value vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: unrecognized mount option "worknr=./file1" or missing value vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: 'file0' not a directory overlayfs: unrecognized mount option "YUQ& t)7Lٙ/{7U.Gި'nG?!Ҹ" or missing value vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: unrecognized mount option "YUQ& t)7Lٙ/{7U.Gި'nG?!Ҹ" or missing value overlayfs: unrecognized mount option "YUQ& t)7Lٙ/{7U.Gި'nG?!Ҹ" or missing value overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: failed to resolve 'YIFBM .': -2 overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: failed to resolve 'YIFBM .': -2 overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: failed to resolve 'YIFBM .': -2 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. kauditd_printk_skb: 64 callbacks suppressed audit: type=1800 audit(1642265570.221:8994): pid=4876 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="sda1" ino=14386 res=0 audit: type=1804 audit(1642265570.251:8995): pid=4876 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir263510277/syzkaller.8t1iQ2/1175/file0" dev="sda1" ino=14386 res=1 overlayfs: 'file0' not a directory overlayfs: './file0' not a directory overlayfs: 'file0' not a directory overlayfs: './file0' not a directory audit: type=1800 audit(1642265570.531:8996): pid=4909 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="sda1" ino=14135 res=0 overlayfs: overlapping lowerdir path audit: type=1804 audit(1642265570.561:8997): pid=4911 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir893734590/syzkaller.qGpK5l/1592/bus" dev="sda1" ino=14150 res=1 audit: type=1804 audit(1642265570.601:8998): pid=4909 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir263510277/syzkaller.8t1iQ2/1176/file0" dev="sda1" ino=14135 res=1 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN audit: type=1800 audit(1642265570.751:8999): pid=4928 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="sda1" ino=14134 res=0 audit: type=1804 audit(1642265570.751:9000): pid=4928 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir263510277/syzkaller.8t1iQ2/1177/file0" dev="sda1" ino=14134 res=1 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN audit: type=1804 audit(1642265571.421:9001): pid=4974 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir893734590/syzkaller.qGpK5l/1593/bus" dev="sda1" ino=14653 res=1 overlayfs: unrecognized mount option "lowerdˀN" or missing value audit: type=1800 audit(1642265571.511:9002): pid=4956 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="sda1" ino=14465 res=0 audit: type=1804 audit(1642265571.511:9003): pid=4956 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir263510277/syzkaller.8t1iQ2/1178/file0" dev="sda1" ino=14465 res=1 overlayfs: unrecognized mount option "lowerdˀN" or missing value vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: missing 'lowerdir' overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: missing 'lowerdir' overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: missing 'lowerdir' overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. overlayfs: filesystem on './bus' not supported as upperdir vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN overlayfs: overlapping lowerdir path overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off.