====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/17943 is trying to acquire lock: 00000000aef888df (&sig->cred_guard_mutex){+.+.}, at: lock_trace fs/proc/base.c:402 [inline] 00000000aef888df (&sig->cred_guard_mutex){+.+.}, at: proc_pid_syscall+0xb8/0x2f0 fs/proc/base.c:635 but task is already holding lock: 00000000db1def41 (&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]#2){+.+.}: 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_syscall+0xb8/0x2f0 fs/proc/base.c:635 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.4/17943: #0: 000000008432aac3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 #1: 00000000db1def41 (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 stack backtrace: CPU: 1 PID: 17943 Comm: syz-executor.4 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_syscall+0xb8/0x2f0 fs/proc/base.c:635 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: 0033:0x7faa651fc109 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:00007faa63b71168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007faa6530ef60 RCX: 00007faa651fc109 RDX: 0000000000002020 RSI: 0000000020000100 RDI: 0000000000000004 RBP: 00007faa6525608d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe8720f1ef R14: 00007faa63b71300 R15: 0000000000022000 kauditd_printk_skb: 2 callbacks suppressed audit: type=1800 audit(1654113244.698:3124): pid=17930 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113246.628:3125): pid=18104 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113246.648:3126): pid=18108 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113247.518:3127): pid=18160 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113247.548:3128): pid=18162 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113247.788:3129): pid=18204 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 ieee802154 phy0 wpan0: encryption failed: -22 ieee802154 phy1 wpan1: encryption failed: -22 audit: type=1800 audit(1654113247.818:3130): pid=18203 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113248.508:3131): pid=18254 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113248.528:3132): pid=18255 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113249.388:3133): pid=18309 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 netlink: 6 bytes leftover after parsing attributes in process `syz-executor.5'. kauditd_printk_skb: 5 callbacks suppressed audit: type=1800 audit(1654113250.368:3139): pid=18397 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113250.398:3140): pid=18400 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113250.398:3141): pid=18401 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113250.678:3142): pid=18423 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113250.708:3143): pid=18424 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113251.378:3144): pid=18461 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113251.418:3145): pid=18464 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113251.418:3146): pid=18466 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113251.708:3147): pid=18492 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="/" dev="fuse" ino=1 res=0 audit: type=1800 audit(1654113251.728:3148): pid=18495 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.0" name="/" dev="fuse" ino=1 res=0