====================================================== WARNING: possible circular locking dependency detected 4.19.53+ #25 Not tainted ------------------------------------------------------ syz-executor.3/1253 is trying to acquire lock: 00000000fd098d9d (&ovl_i_mutex_dir_key[depth]#2){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] 00000000fd098d9d (&ovl_i_mutex_dir_key[depth]#2){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1687 but task is already holding lock: 000000003056e344 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x55/0x120 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){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0xf7/0x1300 kernel/locking/mutex.c:1072 mutex_lock_killable_nested+0x16/0x20 kernel/locking/mutex.c:1102 lock_trace+0x4a/0xe0 fs/proc/base.c:384 proc_pid_stack+0x13e/0x2c0 fs/proc/base.c:434 proc_single_show+0xf0/0x180 fs/proc/base.c:737 seq_read+0x4ca/0x1110 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+0x490/0x640 fs/read_write.c:925 vfs_readv+0xf0/0x160 fs/read_write.c:987 do_preadv+0x1c4/0x280 fs/read_write.c:1071 __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x9a/0xf0 fs/read_write.c:1116 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&p->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0xf7/0x1300 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 seq_read+0x71/0x1110 fs/seq_file.c:161 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x490/0x640 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+0x478/0x890 fs/splice.c:417 do_splice_to+0x127/0x180 fs/splice.c:881 splice_direct_to_actor+0x256/0x890 fs/splice.c:953 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062 do_sendfile+0x597/0xce0 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+0x1dd/0x220 fs/read_write.c:1494 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (sb_writers#4){.+.+}: percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x20b/0x360 fs/super.c:1387 sb_start_write include/linux/fs.h:1578 [inline] mnt_want_write+0x3f/0xc0 fs/namespace.c:360 ovl_want_write+0x76/0xa0 fs/overlayfs/util.c:24 ovl_do_remove+0xf8/0xd90 fs/overlayfs/dir.c:843 ovl_rmdir+0x1b/0x20 fs/overlayfs/dir.c:893 vfs_rmdir fs/namei.c:3879 [inline] vfs_rmdir+0x196/0x460 fs/namei.c:3858 do_rmdir+0x39e/0x420 fs/namei.c:3940 __do_sys_rmdir fs/namei.c:3958 [inline] __se_sys_rmdir fs/namei.c:3956 [inline] __x64_sys_rmdir+0x36/0x40 fs/namei.c:3956 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&ovl_i_mutex_dir_key[depth]#2){++++}: lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3900 down_read+0x3b/0xb0 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:757 [inline] lookup_slow+0x4a/0x80 fs/namei.c:1687 walk_component+0x747/0x2000 fs/namei.c:1810 link_path_walk.part.0+0x980/0x1330 fs/namei.c:2141 link_path_walk fs/namei.c:2072 [inline] path_openat+0x1f9/0x4690 fs/namei.c:3533 do_filp_open+0x1a1/0x280 fs/namei.c:3564 do_open_execat+0x140/0x660 fs/exec.c:853 __do_execve_file.isra.0+0x15a4/0x2150 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+0x8f/0xc0 fs/exec.c:1959 do_syscall_64+0xfd/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.3/1253: #0: 000000003056e344 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x55/0x120 fs/exec.c:1404 stack backtrace: CPU: 1 PID: 1253 Comm: syz-executor.3 Not tainted 4.19.53+ #25 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+0x172/0x1f0 lib/dump_stack.c:113 print_circular_bug.isra.0.cold+0x1cc/0x28f 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+0x2e6d/0x48f0 kernel/locking/lockdep.c:3411 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3900 down_read+0x3b/0xb0 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:757 [inline] lookup_slow+0x4a/0x80 fs/namei.c:1687 walk_component+0x747/0x2000 fs/namei.c:1810 link_path_walk.part.0+0x980/0x1330 fs/namei.c:2141 link_path_walk fs/namei.c:2072 [inline] path_openat+0x1f9/0x4690 fs/namei.c:3533 do_filp_open+0x1a1/0x280 fs/namei.c:3564 do_open_execat+0x140/0x660 fs/exec.c:853 __do_execve_file.isra.0+0x15a4/0x2150 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+0x8f/0xc0 fs/exec.c:1959 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0e73379c78 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 00000000200006c0 RSI: 0000000020000500 RDI: 00000000200001c0 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0e7337a6d4 R13: 00000000004bf96d R14: 00000000004d1250 R15: 00000000ffffffff protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 overlayfs: unrecognized mount option ".lwerdir=.:file0#?KNiw*Md5r.ڑwo_0?Ὰ1'DC\" or missing value kobject: 'loop5' (00000000478bd3a0): kobject_uevent_env kobject: 'loop5' (00000000478bd3a0): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop1' (000000008742f9be): kobject_uevent_env kobject: 'loop1' (000000008742f9be): fill_kobj_path: path = '/devices/virtual/block/loop1' usb usb2: usbfs: process 1544 (syz-executor.5) did not claim interface 0 before use kobject: 'loop2' (000000000e58a66d): kobject_uevent_env overlayfs: filesystem on './file0' not supported as upperdir kobject: 'loop2' (000000000e58a66d): fill_kobj_path: path = '/devices/virtual/block/loop2' overlayfs: unrecognized mount option ".lwerdir=.:file0#?KNiw*Md5r.ڑwo_0?Ὰ1'DC\" or missing value kobject: 'loop2' (000000000e58a66d): kobject_uevent_env kobject: 'loop2' (000000000e58a66d): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop3' (000000005c5f5a11): kobject_uevent_env kobject: 'loop3' (000000005c5f5a11): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop0' (00000000ca4c3e30): kobject_uevent_env netlink: 'syz-executor.2': attribute type 16 has an invalid length. kobject: 'loop0' (00000000ca4c3e30): fill_kobj_path: path = '/devices/virtual/block/loop0' kauditd_printk_skb: 108 callbacks suppressed audit: type=1400 audit(1561182456.414:2736): avc: denied { map } for pid=1855 comm="blkid" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop4' (00000000a4de9ffa): kobject_uevent_env audit: type=1400 audit(1561182456.444:2737): avc: denied { map } for pid=1786 comm="blkid" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop4' (00000000a4de9ffa): fill_kobj_path: path = '/devices/virtual/block/loop4' overlayfs: unrecognized mount option "2" or missing value audit: type=1400 audit(1561182456.454:2738): avc: denied { map } for pid=1786 comm="blkid" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 overlayfs: unrecognized mount option "/proc/self/net/pfkey" or missing value audit: type=1400 audit(1561182456.454:2739): avc: denied { map } for pid=1855 comm="blkid" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 usb usb2: usbfs: process 1883 (syz-executor.5) did not claim interface 0 before use audit: type=1400 audit(1561182456.464:2740): avc: denied { map } for pid=1783 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 overlayfs: unrecognized mount option ".lwerdir=.:file0#?KNiw*Md5r.ڑwo_0?Ὰ1'DC\" or missing value audit: type=1400 audit(1561182456.464:2741): avc: denied { map } for pid=1783 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 netlink: 'syz-executor.2': attribute type 16 has an invalid length. audit: type=1400 audit(1561182456.494:2742): avc: denied { map } for pid=1855 comm="blkid" path="/etc/ld.so.cache" dev="sda1" ino=2251 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1561182456.534:2743): avc: denied { map } for pid=1786 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1561182456.534:2744): avc: denied { map } for pid=1786 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop4' (00000000a4de9ffa): kobject_uevent_env kobject: 'loop4' (00000000a4de9ffa): fill_kobj_path: path = '/devices/virtual/block/loop4' audit: type=1400 audit(1561182456.554:2745): avc: denied { map } for pid=1855 comm="blkid" path="/lib/x86_64-linux-gnu/libblkid.so.1.1.0" dev="sda1" ino=2825 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop5' (00000000478bd3a0): kobject_uevent_env kobject: 'loop5' (00000000478bd3a0): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop1' (000000008742f9be): kobject_uevent_env kobject: 'loop1' (000000008742f9be): fill_kobj_path: path = '/devices/virtual/block/loop1' netlink: 'syz-executor.2': attribute type 16 has an invalid length. kobject: 'loop0' (00000000ca4c3e30): kobject_uevent_env usb usb2: usbfs: process 2094 (syz-executor.5) did not claim interface 0 before use kobject: 'loop0' (00000000ca4c3e30): fill_kobj_path: path = '/devices/virtual/block/loop0' overlayfs: failed to resolve './file1ǯbSӞ0ZLU_d &SJN@2Tc1FY#.U{JsMsZbM˿': -2 kobject: 'loop3' (000000005c5f5a11): kobject_uevent_env kobject: 'loop3' (000000005c5f5a11): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop2' (000000000e58a66d): kobject_uevent_env kobject: 'loop2' (000000000e58a66d): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop4' (00000000a4de9ffa): kobject_uevent_env kobject: 'loop4' (00000000a4de9ffa): fill_kobj_path: path = '/devices/virtual/block/loop4' net_ratelimit: 22 callbacks suppressed protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 overlayfs: unrecognized mount option "lower:file0" or missing value usb usb2: usbfs: process 2331 (syz-executor.5) did not claim interface 0 before use protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 overlayfs: unrecognized mount option "lower:file0" or missing value Unknown ioctl 1076646722 protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 kobject: 'loop1' (000000008742f9be): kobject_uevent_env overlayfs: missing 'workdir' kobject: 'loop1' (000000008742f9be): fill_kobj_path: path = '/devices/virtual/block/loop1' Unknown ioctl 1076646722 kobject: 'loop4' (00000000a4de9ffa): kobject_uevent_env kobject: 'loop4' (00000000a4de9ffa): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (00000000ca4c3e30): kobject_uevent_env kobject: 'loop0' (00000000ca4c3e30): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop5' (00000000478bd3a0): kobject_uevent_env kobject: 'loop5' (00000000478bd3a0): fill_kobj_path: path = '/devices/virtual/block/loop5' usb usb2: usbfs: process 2566 (syz-executor.5) did not claim interface 0 before use overlayfs: unrecognized mount option "uppeile0 lowerdi6XWr=.:file0" or missing value kobject: 'loop2' (000000000e58a66d): kobject_uevent_env kobject: 'loop2' (000000000e58a66d): fill_kobj_path: path = '/devices/virtual/block/loop2' overlayfs: unrecognized mount option "uppile0" or missing value kobject: 'loop3' (000000005c5f5a11): kobject_uevent_env kobject: 'loop3' (000000005c5f5a11): fill_kobj_path: path = '/devices/virtual/block/loop3' kauditd_printk_skb: 142 callbacks suppressed audit: type=1400 audit(1561182461.424:2888): avc: denied { map } for pid=2598 comm="blkid" path="/lib/x86_64-linux-gnu/libblkid.so.1.1.0" dev="sda1" ino=2825 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1561182461.474:2889): avc: denied { map } for pid=2598 comm="blkid" path="/lib/x86_64-linux-gnu/libblkid.so.1.1.0" dev="sda1" ino=2825 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 overlayfs: unrecognized mount option "uppile0" or missing value kobject: 'loop1' (000000008742f9be): kobject_uevent_env audit: type=1400 audit(1561182461.534:2890): avc: denied { map } for pid=2598 comm="blkid" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop1' (000000008742f9be): fill_kobj_path: path = '/devices/virtual/block/loop1' audit: type=1400 audit(1561182461.544:2891): avc: denied { map } for pid=2598 comm="blkid" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop4' (00000000a4de9ffa): kobject_uevent_env audit: type=1400 audit(1561182461.654:2892): avc: denied { map } for pid=2598 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop4' (00000000a4de9ffa): fill_kobj_path: path = '/devices/virtual/block/loop4' audit: type=1400 audit(1561182461.674:2893): avc: denied { map } for pid=2598 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1561182461.734:2894): avc: denied { map } for pid=2742 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop0' (00000000ca4c3e30): kobject_uevent_env kobject: 'loop0' (00000000ca4c3e30): fill_kobj_path: path = '/devices/virtual/block/loop0' usb usb2: usbfs: process 2789 (syz-executor.5) did not claim interface 0 before use audit: type=1400 audit(1561182461.734:2895): avc: denied { map } for pid=2742 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Unknown ioctl 1076646722 audit: type=1400 audit(1561182461.744:2896): avc: denied { map } for pid=2727 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1561182461.774:2897): avc: denied { map } for pid=2727 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 kobject: 'loop5' (00000000478bd3a0): kobject_uevent_env kobject: 'loop5' (00000000478bd3a0): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop2' (000000000e58a66d): kobject_uevent_env kobject: 'loop2' (000000000e58a66d): fill_kobj_path: path = '/devices/virtual/block/loop2' usb usb2: usbfs: process 3075 (syz-executor.5) did not claim interface 0 before use overlayfs: filesystem on './file1' not supported as upperdir kobject: 'loop1' (000000008742f9be): kobject_uevent_env kobject: 'loop1' (000000008742f9be): fill_kobj_path: path = '/devices/virtual/block/loop1' overlayfs: filesystem on './file1' not supported as upperdir kobject: 'loop4' (00000000a4de9ffa): kobject_uevent_env kobject: 'loop4' (00000000a4de9ffa): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (00000000ca4c3e30): kobject_uevent_env kobject: 'loop0' (00000000ca4c3e30): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop3' (000000005c5f5a11): kobject_uevent_env kobject: 'loop3' (000000005c5f5a11): fill_kobj_path: path = '/devices/virtual/block/loop3'