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| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| upstream | possible deadlock in ext4_xattr_get ext4 | 4 | C | inconclusive | 3 | 800d | 1073d | 22/29 | fixed on 2023/07/01 16:05 | |
| linux-4.19 | possible deadlock in ext4_xattr_get | 4 | C | error | 1 | 1176d | 1176d | 0/1 | upstream: reported C repro on 2022/04/27 05:09 |
| Created | Duration | User | Patch | Repo | Result |
|---|---|---|---|---|---|
| 2023/02/27 00:32 | 14m | retest repro | linux-4.14.y | report log | |
| 2022/11/08 14:30 | 10m | retest repro | linux-4.14.y | report log |
EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue
======================================================
WARNING: possible circular locking dependency detected
4.14.276-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor197/7982 is trying to acquire lock:
(&ei->xattr_sem){++++}, at: [<ffffffff81c810e7>] ext4_xattr_get+0x107/0x8b0 fs/ext4/xattr.c:647
but task is already holding lock:
(&ea_inode->i_rwsem#10/1){+.+.}, at: [<ffffffff81863712>] inode_lock include/linux/fs.h:719 [inline]
(&ea_inode->i_rwsem#10/1){+.+.}, at: [<ffffffff81863712>] chown_common+0x272/0x4b0 fs/open.c:628
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&ea_inode->i_rwsem#10/1){+.+.}:
down_write+0x34/0x90 kernel/locking/rwsem.c:54
inode_lock include/linux/fs.h:719 [inline]
ext4_xattr_inode_create fs/ext4/xattr.c:1458 [inline]
ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1541 [inline]
ext4_xattr_set_entry+0x258a/0x3180 fs/ext4/xattr.c:1669
ext4_xattr_ibody_set+0x73/0x280 fs/ext4/xattr.c:2245
ext4_xattr_set_handle+0x518/0xda0 fs/ext4/xattr.c:2402
ext4_xattr_set+0x118/0x230 fs/ext4/xattr.c:2514
__vfs_setxattr+0xdc/0x130 fs/xattr.c:150
__vfs_setxattr_noperm+0xfd/0x3d0 fs/xattr.c:181
__vfs_setxattr_locked+0x14d/0x250 fs/xattr.c:239
vfs_setxattr+0xcf/0x230 fs/xattr.c:256
setxattr+0x1a9/0x300 fs/xattr.c:523
path_setxattr+0x118/0x130 fs/xattr.c:542
SYSC_setxattr fs/xattr.c:557 [inline]
SyS_setxattr+0x36/0x50 fs/xattr.c:553
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
-> #0 (&ei->xattr_sem){++++}:
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
down_read+0x36/0x80 kernel/locking/rwsem.c:24
ext4_xattr_get+0x107/0x8b0 fs/ext4/xattr.c:647
__vfs_getxattr+0xb9/0x100 fs/xattr.c:349
cap_inode_need_killpriv+0x3c/0x50 security/commoncap.c:307
security_inode_need_killpriv+0x66/0xa0 security/security.c:791
notify_change+0x7d7/0xd10 fs/attr.c:250
chown_common+0x40b/0x4b0 fs/open.c:631
SYSC_fchownat fs/open.c:661 [inline]
SyS_fchownat+0xf6/0x190 fs/open.c:641
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ea_inode->i_rwsem#10/1);
lock(&ei->xattr_sem);
lock(&ea_inode->i_rwsem#10/1);
lock(&ei->xattr_sem);
*** DEADLOCK ***
2 locks held by syz-executor197/7982:
#0: (sb_writers#3){.+.+}, at: [<ffffffff818df99a>] sb_start_write include/linux/fs.h:1551 [inline]
#0: (sb_writers#3){.+.+}, at: [<ffffffff818df99a>] mnt_want_write+0x3a/0xb0 fs/namespace.c:386
#1: (&ea_inode->i_rwsem#10/1){+.+.}, at: [<ffffffff81863712>] inode_lock include/linux/fs.h:719 [inline]
#1: (&ea_inode->i_rwsem#10/1){+.+.}, at: [<ffffffff81863712>] chown_common+0x272/0x4b0 fs/open.c:628
stack backtrace:
CPU: 1 PID: 7982 Comm: syz-executor197 Not tainted 4.14.276-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258
check_prev_add kernel/locking/lockdep.c:1905 [inline]
check_prevs_add kernel/locking/lockdep.c:2022 [inline]
validate_chain kernel/locking/lockdep.c:2464 [inline]
__lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
down_read+0x36/0x80 kernel/locking/rwsem.c:24
ext4_xattr_get+0x107/0x8b0 fs/ext4/xattr.c:647
__vfs_getxattr+0xb9/0x100 fs/xattr.c:349
cap_inode_need_killpriv+0x3c/0x50 security/commoncap.c:307
security_inode_need_killpriv+0x66/0xa0 security/security.c:791
notify_change+0x7d7/0xd10 fs/attr.c:250
chown_common+0x40b/0x4b0 fs/open.c:631
SYSC_fchownat fs/open.c:661 [inline]
SyS_fchownat+0xf6/0x190 fs/open.c:641
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f5d23e20109
RSP: 002b:00007fff191c3c98 EFLAGS: 00000246 ORIG_RAX: 0000000000000104
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2022/04/27 03:33 | linux-4.14.y | 15a1c6b6f516 | 1fa34c1b | .config | console log | report | syz | C | ci2-linux-4-14 | possible deadlock in ext4_xattr_get |