====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/28479 is trying to acquire lock: 0000000076005eea (&sig->cred_guard_mutex){+.+.}, at: lock_trace fs/proc/base.c:402 [inline] 0000000076005eea (&sig->cred_guard_mutex){+.+.}, at: proc_pid_stack+0x160/0x350 fs/proc/base.c:452 but task is already holding lock: 0000000056c7f661 (&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 proc_reg_read+0x1bd/0x2d0 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+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_link+0x73/0x2b0 fs/overlayfs/dir.c:676 vfs_link+0x7e6/0xc80 fs/namei.c:4243 do_linkat+0x52a/0x810 fs/namei.c:4311 __do_sys_link fs/namei.c:4340 [inline] __se_sys_link fs/namei.c:4338 [inline] __x64_sys_link+0x5d/0x80 fs/namei.c:4338 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (&ovl_i_mutex_key[depth]){+.+.}: inode_lock include/linux/fs.h:748 [inline] process_measurement+0x926/0x1440 security/integrity/ima/ima_main.c:205 ima_file_check+0xb9/0x100 security/integrity/ima/ima_main.c:391 do_last fs/namei.c:3425 [inline] path_openat+0x7e4/0x2df0 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_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_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: 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.2/28479: #0: 00000000903d161a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 #1: 0000000056c7f661 (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 stack backtrace: CPU: 1 PID: 28479 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 __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_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_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: 0033:0x7f343a800109 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:00007f3439175168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f343a912f60 RCX: 00007f343a800109 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f343a85a0ad R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffce67a2bff R14: 00007f3439175300 R15: 0000000000022000 audit: type=1804 audit(1654857183.783:1623): pid=28483 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2052/bus/file0" dev="sda1" ino=17218 res=1 audit: type=1804 audit(1654857183.783:1624): pid=28488 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2053/bus/file0" dev="sda1" ino=17218 res=1 audit: type=1804 audit(1654857183.783:1625): pid=28492 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2054/bus/file0" dev="sda1" ino=17218 res=1 audit: type=1804 audit(1654857183.783:1626): pid=28494 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2055/bus/file0" dev="sda1" ino=17218 res=1 audit: type=1804 audit(1654857183.783:1627): pid=28496 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2056/bus/file0" dev="sda1" ino=17218 res=1 audit: type=1804 audit(1654857184.193:1628): pid=28499 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir1547870246/syzkaller.8TUu3e/3204/bus" dev="sda1" ino=13913 res=1 audit: type=1804 audit(1654857184.353:1629): pid=28515 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2057/bus/file0" dev="sda1" ino=14538 res=1 wlan1: No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge) audit: type=1804 audit(1654857185.404:1630): pid=28530 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2058/bus/file0" dev="sda1" ino=14621 res=1 kauditd_printk_skb: 2 callbacks suppressed audit: type=1804 audit(1654857187.964:1633): pid=28651 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2060/bus/file0" dev="sda1" ino=14017 res=1 audit: type=1804 audit(1654857189.174:1634): pid=28683 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2061/bus/file0" dev="sda1" ino=14867 res=1 audit: type=1804 audit(1654857190.534:1635): pid=28736 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2062/bus/file0" dev="sda1" ino=14639 res=1 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 28752 Comm: syz-executor.5 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0xa/0xf lib/fault-inject.c:149 audit: type=1804 audit(1654857191.714:1636): pid=28762 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2063/bus/file0" dev="sda1" ino=15057 res=1 __should_failslab+0x115/0x180 mm/failslab.c:32 should_failslab+0x5/0x10 mm/slab_common.c:1590 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc_node mm/slab.c:3304 [inline] kmem_cache_alloc_node_trace+0x244/0x3b0 mm/slab.c:3666 __do_kmalloc_node mm/slab.c:3688 [inline] __kmalloc_node+0x38/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:557 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:423 kvmalloc include/linux/mm.h:577 [inline] seq_buf_alloc fs/seq_file.c:35 [inline] seq_read+0x85c/0x11c0 fs/seq_file.c:207 proc_reg_read+0x1bd/0x2d0 fs/proc/inode.c:231 audit: type=1804 audit(1654857191.714:1637): pid=28765 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2064/bus/file0" dev="sda1" ino=15057 res=1 __vfs_read+0xf7/0x750 fs/read_write.c:416 audit: type=1804 audit(1654857191.714:1638): pid=28767 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2065/bus/file0" dev="sda1" ino=15057 res=1 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: 0033:0x7efd86224109 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:00007efd84b99168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007efd86336f60 RCX: 00007efd86224109 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007efd84b991d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffdf9da81ef R14: 00007efd84b99300 R15: 0000000000022000 audit: type=1804 audit(1654857191.974:1639): pid=28769 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2066/bus/file0" dev="sda1" ino=13912 res=1 audit: type=1804 audit(1654857192.004:1640): pid=28772 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2067/bus/file0" dev="sda1" ino=14630 res=1 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. audit: type=1804 audit(1654857192.734:1641): pid=28875 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir2386926148/syzkaller.TkyqVz/2068/bus/file0" dev="sda1" ino=14630 res=1