====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/11987 is trying to acquire lock: 00000000aee8d5c1 (&sig->cred_guard_mutex){+.+.}, at: lock_trace fs/proc/base.c:402 [inline] 00000000aee8d5c1 (&sig->cred_guard_mutex){+.+.}, at: proc_pid_stack+0x160/0x350 fs/proc/base.c:452 but task is already holding lock: 00000000e9f9f7a7 (&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 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#7){.+.+}: 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 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 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 do_preadv fs/read_write.c:1071 [inline] __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1116 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#7 --> &p->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->lock); lock(sb_writers#7); lock(&p->lock); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 1 lock held by syz-executor.0/11987: #0: 00000000e9f9f7a7 (&p->lock){+.+.}, at: seq_read+0x6b/0x11c0 fs/seq_file.c:164 stack backtrace: CPU: 1 PID: 11987 Comm: syz-executor.0 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 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 do_preadv fs/read_write.c:1071 [inline] __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1116 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f6c39b9e109 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:00007f6c38513168 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00007f6c39cb0f60 RCX: 00007f6c39b9e109 RDX: 0000000000000186 RSI: 00000000200017c0 RDI: 0000000000000004 RBP: 00007f6c39bf80ad R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffec612a19f R14: 00007f6c38513300 R15: 0000000000022000 new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored raw_sendmsg: syz-executor.0 forgot to set AF_INET. Fix it! netlink: 'syz-executor.4': attribute type 7 has an invalid length. netlink: 'syz-executor.4': attribute type 7 has an invalid length. netlink: 'syz-executor.4': attribute type 7 has an invalid length. netlink: 'syz-executor.4': attribute type 7 has an invalid length. audit: type=1804 audit(1654717139.318:201): pid=12571 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir1352106878/syzkaller.6bK2YM/579/bus" dev="sda1" ino=14039 res=1 audit: type=1804 audit(1654717139.348:202): pid=12571 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.3" name="/root/syzkaller-testdir1352106878/syzkaller.6bK2YM/579/bus" dev="sda1" ino=14039 res=1 audit: type=1804 audit(1654717139.368:203): pid=12571 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.3" name="/root/syzkaller-testdir1352106878/syzkaller.6bK2YM/579/bus" dev="sda1" ino=14039 res=1 *** Guest State *** IPVS: sync thread started: state = MASTER, mcast_ifn = macvlan1, syncid = 3, id = 0 CR0: actual=0x0000000000000030, shadow=0x0000000060000010, gh_mask=fffffffffffffff7 audit: type=1804 audit(1654717139.438:204): pid=12578 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.3" name="/root/syzkaller-testdir1352106878/syzkaller.6bK2YM/579/bus" dev="sda1" ino=14039 res=1 CR4: actual=0x0000000000002040, shadow=0x0000000000000000, gh_mask=ffffffffffffe871 CR3 = 0x0000000000000000 RSP = 0x0000000000000000 RIP = 0x000000000000fff0 RFLAGS=0x00000002 DR7 = 0x0000000000000400 Sysenter RSP=0000000000000000 CS:RIP=0000:0000000000000000 CS: sel=0xf000, attr=0x0009b, limit=0x0000ff00, base=0x6d766b2f7665642f DS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 SS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 ES: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 FS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 GS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 GDTR: limit=0x0000ffff, base=0x0000000000000000 LDTR: sel=0x0000, attr=0x00082, limit=0x0000ffff, base=0x0000000000000000 IDTR: limit=0x0000ffff, base=0x0000000000000000 TR: sel=0x0000, attr=0x0008b, limit=0x0000ffff, base=0x0000000000000000 EFER = 0x0000000000000000 PAT = 0x0007040600070406 DebugCtl = 0x0000000000000000 DebugExceptions = 0x0000000000000000 Interruptibility = 00000000 ActivityState = 00000000 *** Host State *** RIP = 0xffffffff811a9c2f RSP = 0xffff8880927c78c0 CS=0010 SS=0018 DS=0000 ES=0000 FS=0000 GS=0000 TR=0040 FSBase=00007fd8f8b46700 GSBase=ffff8880ba100000 TRBase=fffffe0000003000 GDTBase=fffffe0000001000 IDTBase=fffffe0000000000 CR0=0000000080050033 CR3=00000000940e4000 CR4=00000000003426e0 Sysenter RSP=fffffe0000003000 CS:RIP=0010:ffffffff88201290 EFER = 0x0000000000000d01 PAT = 0x0407050600070106 *** Control State *** PinBased=0000003f CPUBased=b5a06dfa SecondaryExec=000000e3 EntryControls=0000d1ff ExitControls=002fefff ExceptionBitmap=00060042 PFECmask=00000000 PFECmatch=00000000 VMEntry: intr_info=00000000 errcode=00000000 ilen=00000000 VMExit: intr_info=00000000 errcode=00000000 ilen=00000000 reason=80000021 qualification=0000000000000000 IDTVectoring: info=00000000 errcode=00000000 TSC Offset = 0xfffffe0917122476 TPR Threshold = 0x00 EPT pointer = 0x000000008f07d01e Virtual processor ID = 0x0001 *** Guest State *** CR0: actual=0x0000000000000030, shadow=0x0000000060000010, gh_mask=fffffffffffffff7 CR4: actual=0x0000000000002040, shadow=0x0000000000000000, gh_mask=ffffffffffffe871 CR3 = 0x0000000000000000 RSP = 0x0000000000000000 RIP = 0x000000000000fff0 RFLAGS=0x00000002 DR7 = 0x0000000000000400 Sysenter RSP=0000000000000000 CS:RIP=0000:0000000000000000 CS: sel=0xf000, attr=0x0009b, limit=0x0000ff00, base=0x6d766b2f7665642f DS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 SS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 audit: type=1804 audit(1654717140.388:205): pid=12641 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir128362840/syzkaller.71oCKJ/500/bus" dev="sda1" ino=14150 res=1 ES: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 FS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 GS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000 Page cache invalidation failure on direct I/O. Possible data corruption due to collision with buffered I/O! GDTR: limit=0x0000ffff, base=0x0000000000000000 audit: type=1804 audit(1654717140.418:206): pid=12645 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir1352106878/syzkaller.6bK2YM/580/bus" dev="sda1" ino=14159 res=1 Page cache invalidation failure on direct I/O. Possible data corruption due to collision with buffered I/O! LDTR: sel=0x0000, attr=0x00082, limit=0x0000ffff, base=0x0000000000000000 *** Guest State *** File: /root/syzkaller-testdir1352106878/syzkaller.6bK2YM/580/bus PID: 12645 Comm: syz-executor.3 CR0: actual=0x0000000000000030, shadow=0x0000000060000010, gh_mask=fffffffffffffff7 File: /root/syzkaller-testdir128362840/syzkaller.71oCKJ/500/bus PID: 12641 Comm: syz-executor.5 IDTR: limit=0x0000ffff, base=0x0000000000000000 CR4: actual=0x0000000000002040, shadow=0x0000000000000000, gh_mask=ffffffffffffe871 audit: type=1804 audit(1654717140.428:207): pid=12641 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.5" name="/root/syzkaller-testdir128362840/syzkaller.71oCKJ/500/bus" dev="sda1" ino=14150 res=1 TR: sel=0x0000, attr=0x0008b, limit=0x0000ffff, base=0x0000000000000000 CR3 = 0x0000000000000000 RSP = 0x0000000000000000 RIP = 0x000000000000fff0 RFLAGS=0x00000002 DR7 = 0x0000000000000400 Sysenter RSP=0000000000000000 CS:RIP=0000:0000000000000000 audit: type=1804 audit(1654717140.438:208): pid=12641 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.5" name="/root/syzkaller-testdir128362840/syzkaller.71oCKJ/500/bus" dev="sda1" ino=14150 res=1 CS: sel=0xf000, attr=0x0009b, limit=0x0000ff00, base=0x6d766b2f7665642f DS: sel=0x0000, attr=0x00093, limit=0x0000ffff, base=0x0000000000000000