Hello, syzbot found the following issue on: HEAD commit: 45db3ab70092 Merge tag '6.9-rc7-ksmbd-fixes' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=144a905c980000 kernel config: https://syzkaller.appspot.com/x/.config?x=a450595960709c8 dashboard link: https://syzkaller.appspot.com/bug?extid=4247fb9b4517c79e3b57 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-45db3ab7.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c94d1aa6cd96/vmlinux-45db3ab7.xz kernel image: https://storage.googleapis.com/syzbot-assets/f9daddfda2f1/bzImage-45db3ab7.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+4247fb9b4517c79e3b57@xxxxxxxxxxxxxxxxxxxxxxxxx EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. ====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc7-syzkaller-00056-g45db3ab70092 #0 Not tainted ------------------------------------------------------ syz-executor.3/30481 is trying to acquire lock: ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:312 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3752 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3833 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: __do_kmalloc_node mm/slub.c:3971 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_node+0xbb/0x480 mm/slub.c:3979 but task is already holding lock: ffff88802a241ec8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ffff88802a241ec8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x156/0x16d0 fs/ext4/xattr.c:2358 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ei->xattr_sem){++++}-{3:3}: down_write+0x3a/0x50 kernel/locking/rwsem.c:1579 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_xattr_set_handle+0x156/0x16d0 fs/ext4/xattr.c:2358 ext4_xattr_set+0x149/0x380 fs/ext4/xattr.c:2545 __vfs_setxattr+0x173/0x1e0 fs/xattr.c:200 __vfs_setxattr_noperm+0x127/0x5e0 fs/xattr.c:234 __vfs_setxattr_locked+0x182/0x260 fs/xattr.c:295 vfs_setxattr+0x146/0x350 fs/xattr.c:321 do_setxattr+0x146/0x170 fs/xattr.c:629 setxattr+0x15d/0x180 fs/xattr.c:652 path_setxattr+0x179/0x1e0 fs/xattr.c:671 __do_sys_lsetxattr fs/xattr.c:694 [inline] __se_sys_lsetxattr fs/xattr.c:690 [inline] __ia32_sys_lsetxattr+0xbd/0x160 fs/xattr.c:690 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (jbd2_handle){++++}-{0:0}: start_this_handle+0x1101/0x15e0 fs/jbd2/transaction.c:463 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:520 __ext4_journal_start_sb+0x358/0x660 fs/ext4/ext4_jbd2.c:112 ext4_sample_last_mounted fs/ext4/file.c:837 [inline] ext4_file_open+0x636/0xc80 fs/ext4/file.c:866 do_dentry_open+0x8da/0x18c0 fs/open.c:955 do_open fs/namei.c:3642 [inline] path_openat+0x1dfb/0x2990 fs/namei.c:3799 do_filp_open+0x1dc/0x430 fs/namei.c:3826 do_sys_openat2+0x17a/0x1e0 fs/open.c:1406 do_sys_open fs/open.c:1421 [inline] __do_sys_openat fs/open.c:1437 [inline] __se_sys_openat fs/open.c:1432 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1432 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (sb_internal){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1664 [inline] sb_start_intwrite include/linux/fs.h:1847 [inline] ext4_evict_inode+0xd7b/0x17d0 fs/ext4/inode.c:212 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x440 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 shrink_kill fs/dcache.c:1048 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156 super_cache_scan+0x32a/0x550 fs/super.c:221 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4774 shrink_many mm/vmscan.c:4835 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935 shrink_node mm/vmscan.c:5894 [inline] kswapd_shrink_node mm/vmscan.c:6704 [inline] balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895 kswapd+0x5ea/0xbf0 mm/vmscan.c:7164 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3698 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712 might_alloc include/linux/sched/mm.h:312 [inline] slab_pre_alloc_hook mm/slub.c:3752 [inline] slab_alloc_node mm/slub.c:3833 [inline] __do_kmalloc_node mm/slub.c:3971 [inline] __kmalloc_node+0xbb/0x480 mm/slub.c:3979 kmalloc_node include/linux/slab.h:648 [inline] kvmalloc_node+0x9d/0x1a0 mm/util.c:634 kvmalloc include/linux/slab.h:766 [inline] ext4_xattr_inode_cache_find fs/ext4/xattr.c:1535 [inline] ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1581 [inline] ext4_xattr_set_entry+0xdc3/0x3b20 fs/ext4/xattr.c:1718 ext4_xattr_block_set+0xd07/0x3080 fs/ext4/xattr.c:2037 ext4_xattr_set_handle+0xf24/0x16d0 fs/ext4/xattr.c:2443 ext4_xattr_set+0x149/0x380 fs/ext4/xattr.c:2545 __vfs_setxattr+0x173/0x1e0 fs/xattr.c:200 __vfs_setxattr_noperm+0x127/0x5e0 fs/xattr.c:234 __vfs_setxattr_locked+0x182/0x260 fs/xattr.c:295 vfs_setxattr+0x146/0x350 fs/xattr.c:321 do_setxattr+0x146/0x170 fs/xattr.c:629 setxattr+0x15d/0x180 fs/xattr.c:652 path_setxattr+0x179/0x1e0 fs/xattr.c:671 __do_sys_setxattr fs/xattr.c:687 [inline] __se_sys_setxattr fs/xattr.c:683 [inline] __ia32_sys_setxattr+0xc0/0x160 fs/xattr.c:683 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: fs_reclaim --> jbd2_handle --> &ei->xattr_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->xattr_sem); lock(jbd2_handle); lock(&ei->xattr_sem); lock(fs_reclaim); *** DEADLOCK *** 3 locks held by syz-executor.3/30481: #0: ffff888076954420 (sb_writers#4){.+.+}-{0:0}, at: path_setxattr+0xc3/0x1e0 fs/xattr.c:669 #1: ffff88802a242200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline] #1: ffff88802a242200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_setxattr+0x123/0x350 fs/xattr.c:320 #2: ffff88802a241ec8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] #2: ffff88802a241ec8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x156/0x16d0 fs/ext4/xattr.c:2358 stack backtrace: CPU: 0 PID: 30481 Comm: syz-executor.3 Not tainted 6.9.0-rc7-syzkaller-00056-g45db3ab70092 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3698 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712 might_alloc include/linux/sched/mm.h:312 [inline] slab_pre_alloc_hook mm/slub.c:3752 [inline] slab_alloc_node mm/slub.c:3833 [inline] __do_kmalloc_node mm/slub.c:3971 [inline] __kmalloc_node+0xbb/0x480 mm/slub.c:3979 kmalloc_node include/linux/slab.h:648 [inline] kvmalloc_node+0x9d/0x1a0 mm/util.c:634 kvmalloc include/linux/slab.h:766 [inline] ext4_xattr_inode_cache_find fs/ext4/xattr.c:1535 [inline] ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1581 [inline] ext4_xattr_set_entry+0xdc3/0x3b20 fs/ext4/xattr.c:1718 ext4_xattr_block_set+0xd07/0x3080 fs/ext4/xattr.c:2037 ext4_xattr_set_handle+0xf24/0x16d0 fs/ext4/xattr.c:2443 ext4_xattr_set+0x149/0x380 fs/ext4/xattr.c:2545 __vfs_setxattr+0x173/0x1e0 fs/xattr.c:200 __vfs_setxattr_noperm+0x127/0x5e0 fs/xattr.c:234 __vfs_setxattr_locked+0x182/0x260 fs/xattr.c:295 vfs_setxattr+0x146/0x350 fs/xattr.c:321 do_setxattr+0x146/0x170 fs/xattr.c:629 setxattr+0x15d/0x180 fs/xattr.c:652 path_setxattr+0x179/0x1e0 fs/xattr.c:671 __do_sys_setxattr fs/xattr.c:687 [inline] __se_sys_setxattr fs/xattr.c:683 [inline] __ia32_sys_setxattr+0xc0/0x160 fs/xattr.c:683 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf72c6579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f5eb85ac EFLAGS: 00000292 ORIG_RAX: 00000000000000e2 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00000000200001c0 RDX: 0000000020001400 RSI: 0000000000000835 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi --- This report is generated by a bot. 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