====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/3012 is trying to acquire lock: 00000000e1a4749f (&sig->cred_guard_mutex){+.+.}, at: do_io_accounting fs/proc/base.c:2750 [inline] 00000000e1a4749f (&sig->cred_guard_mutex){+.+.}, at: proc_tgid_io_accounting+0x1cf/0x7f0 fs/proc/base.c:2799 but task is already holding lock: 000000003c29776b (&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 full_proxy_read+0x118/0x170 fs/debugfs/file.c:195 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:1502 [inline] __se_sys_sendfile64+0xc4/0x160 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]#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_tgid_io_accounting+0x1cf/0x7f0 fs/proc/base.c:2799 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 other info that might help us debug this: overlayfs: failed to resolve './file1': -2 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.4/3012: #0: 000000005fb87211 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 #1: 000000003c29776b (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 stack backtrace: CPU: 1 PID: 3012 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 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 do_io_accounting fs/proc/base.c:2750 [inline] proc_tgid_io_accounting+0x1cf/0x7f0 fs/proc/base.c:2799 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 RIP: 0033:0x7f6c4e7dd279 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:00007f6c4d152168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6c4e8eff80 RCX: 00007f6c4e7dd279 RDX: 0000000000002020 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007f6c4e837189 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffedd51baff R14: 00007f6c4d152300 R15: 0000000000022000 netlink: 76 bytes leftover after parsing attributes in process `syz-executor.4'. input: syz0 as /devices/virtual/input/input2042 netlink: 76 bytes leftover after parsing attributes in process `syz-executor.4'. input: syz0 as /devices/virtual/input/input2043 input: syz0 as /devices/virtual/input/input2044 overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2045 netlink: 76 bytes leftover after parsing attributes in process `syz-executor.4'. input: syz0 as /devices/virtual/input/input2046 overlayfs: failed to resolve './file1': -2 overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2047 input: syz0 as /devices/virtual/input/input2048 input: syz0 as /devices/virtual/input/input2049 overlayfs: unrecognized mount option "workdir=./file1" or missing value input: syz0 as /devices/virtual/input/input2050 overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2051 input: syz0 as /devices/virtual/input/input2052 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2053 uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2054 overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory overlayfs: unrecognized mount option "workdir=./file1" or missing value input: syz0 as /devices/virtual/input/input2055 uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first input: syz0 as /devices/virtual/input/input2056 uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first input: syz0 as /devices/virtual/input/input2057 overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first overlayfs: unrecognized mount option "workdir=./file1" or missing value uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2058 uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first overlayfs: './bus' not a directory uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first input: syz0 as /devices/virtual/input/input2059 uinput: write device info first uinput: write device info first overlayfs: unrecognized mount option "uppmrdir=./qitbus" or missing value uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first input: syz0 as /devices/virtual/input/input2060 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2061 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2062 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2063 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: unrecognized mount option "uppmrdir=./qitbus" or missing value overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2064 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2065 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: unrecognized mount option "uppmrdir=./qitbus" or missing value overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2066 overlayfs: failed to resolve './file0': -2 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2067 REISERFS warning (device loop1): super-6504 reiserfs_getopt: the option "grpjquota" requires an argument overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: unrecognized mount option "uppmrdir=./qitbus" or missing value overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2068 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2069 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2070 overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2071 overlayfs: failed to resolve './file0': -2 REISERFS warning (device loop1): super-6504 reiserfs_getopt: the option "grpjquota" requires an argument overlayfs: unrecognized mount option "upperworkdir=./file1" or missing value input: syz0 as /devices/virtual/input/input2072 overlayfs: failed to resolve './bus': -2 input: syz0 as /devices/virtual/input/input2073 input: syz0 as /devices/virtual/input/input2074 input: syz0 as /devices/virtual/input/input2075 input: syz0 as /devices/virtual/input/input2076 input: syz0 as /devices/virtual/input/input2077 input: syz0 as /devices/virtual/input/input2078 overlayfs: failed to resolve './file1': -2 input: syz0 as /devices/virtual/input/input2079 input: syz0 as /devices/virtual/input/input2080 input: syz0 as /devices/virtual/input/input2081 input: syz0 as /devices/virtual/input/input2082 input: syz0 as /devices/virtual/input/input2083 could not allocate digest TFM handle sha256-ce input: syz0 as /devices/virtual/input/input2084 input: syz0 as /devices/virtual/input/input2085 overlayfs: failed to resolve './file1': -2 input: syz0 as /devices/virtual/input/input2086 input: syz0 as /devices/virtual/input/input2087 input: syz0 as /devices/virtual/input/input2088 input: syz0 as /devices/virtual/input/input2089 could not allocate digest TFM handle sha256-ce could not allocate digest TFM handle sha256-ce overlayfs: failed to resolve './file1': -2 input: syz0 as /devices/virtual/input/input2090 input: syz0 as /devices/virtual/input/input2091 input: syz0 as /devices/virtual/input/input2092 overlayfs: unrecognized mount option "measure" or missing value input: syz0 as /devices/virtual/input/input2093 overlayfs: './bus' not a directory input: syz0 as /devices/virtual/input/input2094 input: syz0 as /devices/virtual/input/input2095 input: syz0 as /devices/virtual/input/input2096 input: syz0 as /devices/virtual/input/input2097 overlayfs: unrecognized mount option "workdir=./file1" or missing value input: syz0 as /devices/virtual/input/input2098 overlayfs: unrecognized mount option "measure" or missing value input: syz0 as /devices/virtual/input/input2099 input: syz0 as /devices/virtual/input/input2100 input: syz0 as /devices/virtual/input/input2101 input: syz0 as /devices/virtual/input/input2102 overlayfs: unrecognized mount option "measure" or missing value input: syz0 as /devices/virtual/input/input2103 uinput: write device info first uinput: write device info first input: syz0 as /devices/virtual/input/input2104 input: syz0 as /devices/virtual/input/input2105 uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first input: syz0 as /devices/virtual/input/input2106 uinput: write device info first input: syz0 as /devices/virtual/input/input2107 uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first uinput: write device info first netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. input: syz0 as /devices/virtual/input/input2108 input: syz0 as /devices/virtual/input/input2109 overlayfs: unrecognized mount option "ҺMX~[h Д1QO7&W-860VʺUx 8GTE 7րg!d&j" or missing value uinput: write device info first input: syz0 as /devices/virtual/input/input2111 uinput: write device info first input: syz0 as /devices/virtual/input/input2113 uinput: write device info first overlayfs: unrecognized mount option "ҺMX~[h Д1QO7&W-860VʺUx 8GTE 7րg!d&j" or missing value input: syz0 as /devices/virtual/input/input2115 input: syz0 as /devices/virtual/input/input2116 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. overlayfs: unrecognized mount option "ҺMX~[h Д1QO7&W-860VʺUx 8GTE 7րg!d&j" or missing value input: syz0 as /devices/virtual/input/input2117 input: syz0 as /devices/virtual/input/input2118 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. input: syz0 as /devices/virtual/input/input2119 input: syz0 as /devices/virtual/input/input2120 input: syz0 as /devices/virtual/input/input2121 input: syz0 as /devices/virtual/input/input2122 overlayfs: failed to resolve './file0': -2 input: syz0 as /devices/virtual/input/input2123 overlayfs: unrecognized mount option "u6pperdir=./bus" or missing value netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. input: syz0 as /devices/virtual/input/input2124 input: syz0 as /devices/virtual/input/input2125 overlayfs: unrecognized mount option "u6pperdir=./bus" or missing value uinput: write device info first input: syz0 as /devices/virtual/input/input2127 uinput: write device info first