overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) ====================================================== WARNING: possible circular locking dependency detected 4.19.109-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/26816 is trying to acquire lock: 000000009f6a6e25 (&ovl_i_mutex_dir_key[depth]#2){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] 000000009f6a6e25 (&ovl_i_mutex_dir_key[depth]#2){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 but task is already holding lock: 000000002998852e (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x51/0x120 fs/exec.c:1404 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&sig->cred_guard_mutex){+.+.}: lock_trace+0x45/0xe0 fs/proc/base.c:402 proc_pid_syscall+0x94/0x240 fs/proc/base.c:635 proc_single_show+0xeb/0x170 fs/proc/base.c:755 seq_read+0x4b9/0x10f0 fs/seq_file.c:229 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x46b/0x640 fs/read_write.c:925 vfs_readv+0xf0/0x160 fs/read_write.c:987 do_preadv+0x1b6/0x270 fs/read_write.c:1071 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&p->lock){+.+.}: seq_read+0x6b/0x10f0 fs/seq_file.c:161 proc_reg_read+0x1bd/0x280 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+0x46b/0x640 fs/read_write.c:925 vfs_readv+0xf0/0x160 fs/read_write.c:987 kernel_readv fs/splice.c:362 [inline] default_file_splice_read+0x478/0x970 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+0x1a8/0x270 fs/splice.c:1068 do_sendfile+0x549/0xc10 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64 fs/read_write.c:1494 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1494 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (sb_writers#4){.+.+}: sb_start_write include/linux/fs.h:1578 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:360 ovl_create_object+0x96/0x290 fs/overlayfs/dir.c:600 lookup_open+0x11f6/0x19b0 fs/namei.c:3235 do_last fs/namei.c:3327 [inline] path_openat+0x13cb/0x4200 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3c0/0x500 fs/open.c:1088 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]#2){++++}: down_read+0x37/0xb0 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:757 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x70a/0x1ee0 fs/namei.c:1811 link_path_walk.part.0+0x8fd/0x1210 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1ed/0x4200 fs/namei.c:3536 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_open_execat+0x124/0x5b0 fs/exec.c:853 __do_execve_file.isra.0+0x1577/0x2110 fs/exec.c:1755 do_execveat_common fs/exec.c:1866 [inline] do_execve fs/exec.c:1883 [inline] __do_sys_execve fs/exec.c:1964 [inline] __se_sys_execve fs/exec.c:1959 [inline] __x64_sys_execve+0x8a/0xb0 fs/exec.c:1959 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]#2 --> &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]#2); *** DEADLOCK *** 1 lock held by syz-executor.5/26816: #0: 000000002998852e (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x51/0x120 fs/exec.c:1404 stack backtrace: CPU: 0 PID: 26816 Comm: syz-executor.5 Not tainted 4.19.109-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+0x188/0x20d lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x1c4/0x282 kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1861 [inline] check_prevs_add kernel/locking/lockdep.c:1974 [inline] validate_chain kernel/locking/lockdep.c:2415 [inline] __lock_acquire+0x2e19/0x49c0 kernel/locking/lockdep.c:3411 lock_acquire+0x170/0x400 kernel/locking/lockdep.c:3903 down_read+0x37/0xb0 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:757 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x70a/0x1ee0 fs/namei.c:1811 link_path_walk.part.0+0x8fd/0x1210 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1ed/0x4200 fs/namei.c:3536 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_open_execat+0x124/0x5b0 fs/exec.c:853 __do_execve_file.isra.0+0x1577/0x2110 fs/exec.c:1755 do_execveat_common fs/exec.c:1866 [inline] do_execve fs/exec.c:1883 [inline] __do_sys_execve fs/exec.c:1964 [inline] __se_sys_execve fs/exec.c:1959 [inline] __x64_sys_execve+0x8a/0xb0 fs/exec.c:1959 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c849 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2d47003c78 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00007f2d470046d4 RCX: 000000000045c849 RDX: 00000000200003c0 RSI: 0000000020000300 RDI: 0000000020000080 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000000a6 R14: 00000000004c3391 R15: 000000000076bf0c overlayfs: failed to verify upper (/file1, ino=219329, err=-116) overlayfs: failed to verify index dir 'upper' xattr overlayfs: try deleting index dir or mounting with '-o index=off' to disable inodes index. overlayfs: filesystem on './file1' not supported as upperdir FAT-fs (loop0): Unrecognized mount option "uid>00000000000000000000" or missing value overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir FAT-fs (loop0): Unrecognized mount option "uid>00000000000000000000" or missing value overlayfs: failed to decode file handle (len=44, type=536871163, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=27462 comm=syz-executor.3 overlayfs: filesystem on './file1' not supported as upperdir audit: type=1400 audit(1584329235.236:574): avc: denied { bind } for pid=27587 comm="syz-executor.1" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1 overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir erofs: read_super, device -> /dev/loop5 erofs: options -> user_xattr,hash,subj_type=$-security,permit_directio,fowner=00000000000000060928,smackfsdef=workdir,subj_user=-,audit,uid>00000000000003237375,subj_role=, erofs: cannot find valid erofs superblock overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: failed to verify upper (/file1, ino=219329, err=-116) overlayfs: failed to verify index dir 'upper' xattr overlayfs: try deleting index dir or mounting with '-o index=off' to disable inodes index. overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir could not allocate digest TFM handle %2 overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to resolve './file1': -2 overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: failed to verify upper (/file1, ino=219329, err=-116) overlayfs: failed to verify index dir 'upper' xattr overlayfs: try deleting index dir or mounting with '-o index=off' to disable inodes index. overlayfs: failed to decode file handle (len=44, type=0, flags=0, err=-22) overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection. overlayfs: filesystem on './file1' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' overlayfs: filesystem on './file1' not supported as upperdir overlayfs: filesystem on './file1' not supported as upperdir overlayfs: filesystem on './file1' not supported as upperdir overlayfs: filesystem on './file1' not supported as upperdir overlayfs: unrecognized mount option "/file1" or missing value overlayfs: unrecognized mount option "/file1" or missing value overlayfs: failed to resolve '0': -2 overlayfs: failed to resolve '0': -2 overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to resolve './file1/file0': -2 overlayfs: failed to resolve './file1/file0': -2 overlayfs: filesystem on './file1' not supported as upperdir ovl_fh_to_dentry: 2 callbacks suppressed overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: unrecognized mount option "ns_export=on" or missing value overlayfs: unrecognized mount option "ns_export=on" or missing value overlayfs: failed to resolve '.`e0': -2 overlayfs: failed to resolve '.`e0': -2 overlayfs: failed to decode file handle (len=44, type=4347, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to decode file handle (len=44, type=4347, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to resolve './file1': -2 overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: unrecognized mount option "fosner=e} YZʽܸT)xc" or missing value overlayfs: unrecognized mount option "fosner=e} YZʽܸT)xc" or missing value overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: unrecognized mount option "wor" or missing value overlayfs: unrecognized mount option "wor" or missing value overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: failed to decode file handle (len=44, type=251, flags=0, err=-22) overlayfs: filesystem on './file1' not supported as upperdir overlayfs: filesystem on './file1' not supported as upperdir