possible deadlock in proc_tid_io_accounting
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syzbot
Sep 21, 2020, 3:35:16 AM9/21/20
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: 015e94d0 Linux 4.19.146
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11e9f8ad900000
kernel config: https://syzkaller.appspot.com/x/.config?x=243dd74ad58a8a57
dashboard link: https://syzkaller.appspot.com/bug?extid=93b87d5eaf895c3ed1e4
compiler: gcc (GCC) 10.1.0-syz 20200507
Unfortunately, I don't have any reproducer for this issue yet.
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+93b87d...@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
4.19.146-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/4694 is trying to acquire lock:
00000000e510df13 (&sig->cred_guard_mutex){+.+.}, at: do_io_accounting fs/proc/base.c:2738 [inline]
00000000e510df13 (&sig->cred_guard_mutex){+.+.}, at: proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2781
but task is already holding lock:
00000000e65342af (&p->lock){+.+.}, at: seq_read+0x6b/0x10c0 fs/seq_file.c:161
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&p->lock){+.+.}:
seq_read+0x6b/0x10c0 fs/seq_file.c:161
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+0x457/0xa10 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+0xf9/0x670 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_do_remove+0xf0/0xdd0 fs/overlayfs/dir.c:843
vfs_rmdir.part.0+0x161/0x430 fs/namei.c:3882
vfs_rmdir fs/namei.c:3865 [inline]
do_rmdir+0x3af/0x420 fs/namei.c:3943
do_syscall_64+0xf9/0x670 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+0x1863/0x2e90 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+0x1ad4/0x23c0 fs/exec.c:1757
do_execveat_common fs/exec.c:1866 [inline]
do_execveat+0x3d/0x50 fs/exec.c:1894
__do_sys_execveat fs/exec.c:1975 [inline]
__se_sys_execveat fs/exec.c:1967 [inline]
__x64_sys_execveat+0xe1/0x120 fs/exec.c:1967
do_syscall_64+0xf9/0x670 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:925 [inline]
__mutex_lock+0xd7/0x13f0 kernel/locking/mutex.c:1072
do_io_accounting fs/proc/base.c:2738 [inline]
proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2781
proc_single_show+0xeb/0x170 fs/proc/base.c:755
seq_read+0x4bc/0x10c0 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+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+0xf9/0x670 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 ***
1 lock held by syz-executor.2/4694:
#0: 00000000e65342af (&p->lock){+.+.}, at: seq_read+0x6b/0x10c0 fs/seq_file.c:161
stack backtrace:
CPU: 1 PID: 4694 Comm: syz-executor.2 Not tainted 4.19.146-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+0x22c/0x33e lib/dump_stack.c:118
print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221
check_prev_add kernel/locking/lockdep.c:1865 [inline]
check_prevs_add kernel/locking/lockdep.c:1978 [inline]
validate_chain kernel/locking/lockdep.c:2419 [inline]
__lock_acquire+0x37ad/0x3ff0 kernel/locking/lockdep.c:3415
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3907
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0xd7/0x13f0 kernel/locking/mutex.c:1072
do_io_accounting fs/proc/base.c:2738 [inline]
proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2781
proc_single_show+0xeb/0x170 fs/proc/base.c:755
seq_read+0x4bc/0x10c0 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+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+0xf9/0x670 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d5f9
Code: 5d b4 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdc4f4f5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 0000000000025900 RCX: 000000000045d5f9
RDX: 000000000000037d RSI: 0000000020000500 RDI: 0000000000000004
RBP: 000000000118cf90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffda93fd33f R14: 00007fdc4f4f69c0 R15: 000000000118cf4c
xt_nat: multiple ranges no longer supported
f2fs_msg: 15 callbacks suppressed
F2FS-fs (loop0): Invalid Fs Meta Ino: node(0) meta(0) root(0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): invalid crc value
xt_nat: multiple ranges no longer supported
9pnet: Insufficient options for proto=fd
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
9pnet: Insufficient options for proto=fd
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
9pnet: Insufficient options for proto=fd
F2FS-fs (loop0): Invalid Fs Meta Ino: node(0) meta(0) root(0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): Invalid Fs Meta Ino: node(0) meta(0) root(0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
9pnet: Insufficient options for proto=fd
9pnet: Insufficient options for proto=fd
9pnet: Insufficient options for proto=fd
xt_nat_checkentry_v0: 7 callbacks suppressed
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
f2fs_msg: 22 callbacks suppressed
F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
xt_nat_checkentry_v0: 12 callbacks suppressed
xt_nat: multiple ranges no longer supported
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot found the following issue on:
HEAD commit: 015e94d0 Linux 4.19.146
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11e9f8ad900000
kernel config: https://syzkaller.appspot.com/x/.config?x=243dd74ad58a8a57
dashboard link: https://syzkaller.appspot.com/bug?extid=93b87d5eaf895c3ed1e4
compiler: gcc (GCC) 10.1.0-syz 20200507
Unfortunately, I don't have any reproducer for this issue yet.
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+93b87d...@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
4.19.146-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/4694 is trying to acquire lock:
00000000e510df13 (&sig->cred_guard_mutex){+.+.}, at: do_io_accounting fs/proc/base.c:2738 [inline]
00000000e510df13 (&sig->cred_guard_mutex){+.+.}, at: proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2781
but task is already holding lock:
00000000e65342af (&p->lock){+.+.}, at: seq_read+0x6b/0x10c0 fs/seq_file.c:161
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&p->lock){+.+.}:
seq_read+0x6b/0x10c0 fs/seq_file.c:161
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+0x457/0xa10 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+0xf9/0x670 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_do_remove+0xf0/0xdd0 fs/overlayfs/dir.c:843
vfs_rmdir.part.0+0x161/0x430 fs/namei.c:3882
vfs_rmdir fs/namei.c:3865 [inline]
do_rmdir+0x3af/0x420 fs/namei.c:3943
do_syscall_64+0xf9/0x670 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+0x1863/0x2e90 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+0x1ad4/0x23c0 fs/exec.c:1757
do_execveat_common fs/exec.c:1866 [inline]
do_execveat+0x3d/0x50 fs/exec.c:1894
__do_sys_execveat fs/exec.c:1975 [inline]
__se_sys_execveat fs/exec.c:1967 [inline]
__x64_sys_execveat+0xe1/0x120 fs/exec.c:1967
do_syscall_64+0xf9/0x670 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:925 [inline]
__mutex_lock+0xd7/0x13f0 kernel/locking/mutex.c:1072
do_io_accounting fs/proc/base.c:2738 [inline]
proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2781
proc_single_show+0xeb/0x170 fs/proc/base.c:755
seq_read+0x4bc/0x10c0 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+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+0xf9/0x670 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 ***
1 lock held by syz-executor.2/4694:
#0: 00000000e65342af (&p->lock){+.+.}, at: seq_read+0x6b/0x10c0 fs/seq_file.c:161
stack backtrace:
CPU: 1 PID: 4694 Comm: syz-executor.2 Not tainted 4.19.146-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+0x22c/0x33e lib/dump_stack.c:118
print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221
check_prev_add kernel/locking/lockdep.c:1865 [inline]
check_prevs_add kernel/locking/lockdep.c:1978 [inline]
validate_chain kernel/locking/lockdep.c:2419 [inline]
__lock_acquire+0x37ad/0x3ff0 kernel/locking/lockdep.c:3415
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3907
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0xd7/0x13f0 kernel/locking/mutex.c:1072
do_io_accounting fs/proc/base.c:2738 [inline]
proc_tid_io_accounting+0x184/0x2b0 fs/proc/base.c:2781
proc_single_show+0xeb/0x170 fs/proc/base.c:755
seq_read+0x4bc/0x10c0 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+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+0xf9/0x670 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d5f9
Code: 5d b4 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdc4f4f5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 0000000000025900 RCX: 000000000045d5f9
RDX: 000000000000037d RSI: 0000000020000500 RDI: 0000000000000004
RBP: 000000000118cf90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffda93fd33f R14: 00007fdc4f4f69c0 R15: 000000000118cf4c
xt_nat: multiple ranges no longer supported
f2fs_msg: 15 callbacks suppressed
F2FS-fs (loop0): Invalid Fs Meta Ino: node(0) meta(0) root(0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): invalid crc value
xt_nat: multiple ranges no longer supported
9pnet: Insufficient options for proto=fd
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
9pnet: Insufficient options for proto=fd
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
9pnet: Insufficient options for proto=fd
F2FS-fs (loop0): Invalid Fs Meta Ino: node(0) meta(0) root(0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): Invalid Fs Meta Ino: node(0) meta(0) root(0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
9pnet: Insufficient options for proto=fd
9pnet: Insufficient options for proto=fd
9pnet: Insufficient options for proto=fd
xt_nat_checkentry_v0: 7 callbacks suppressed
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
f2fs_msg: 22 callbacks suppressed
F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
xt_nat: multiple ranges no longer supported
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
xt_nat: multiple ranges no longer supported
F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Mounted with checkpoint version = 79df1d6d
F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
xt_nat_checkentry_v0: 12 callbacks suppressed
xt_nat: multiple ranges no longer supported
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot
Mar 30, 2023, 4:11:30 AM3/30/23
to syzkaller...@googlegroups.com
Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.
Crashes did not happen for a while, no reproducer and no activity.
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