EXT4-fs: Warning: mounting with an experimental mount option 'dioread_nolock' for blocksize < PAGE_SIZE EXT4-fs (loop0): mounted filesystem without journal. Quota mode: none. ====================================================== WARNING: possible circular locking dependency detected 6.1.0-rc8-syzkaller-00172-ga5541c0811a0-dirty #0 Not tainted ------------------------------------------------------ syz-executor.0/3668 is trying to acquire lock: ffff0000cf16bd60 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] ffff0000cf16bd60 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_xattr_inode_create fs/ext4/xattr.c:1453 [inline] ffff0000cf16bd60 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1536 [inline] ffff0000cf16bd60 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_xattr_set_entry+0xdbc/0xe00 fs/ext4/xattr.c:1664 but task is already holding lock: ffff0000cf16b098 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ffff0000cf16b098 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0xd0/0x9a0 fs/ext4/xattr.c:2308 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ei->xattr_sem){++++}-{3:3}: down_read+0x5c/0x78 kernel/locking/rwsem.c:1509 ext4_xattr_get+0x90/0x418 fs/ext4/xattr.c:665 ext4_xattr_security_get+0x40/0x54 fs/ext4/xattr_security.c:20 __vfs_getxattr+0x1fc/0x20c fs/xattr.c:407 cap_inode_need_killpriv+0x34/0x5c security/commoncap.c:301 security_inode_need_killpriv+0x34/0x88 security/security.c:1422 dentry_needs_remove_privs fs/inode.c:1995 [inline] __file_remove_privs+0xe0/0x308 fs/inode.c:2026 file_modified_flags+0x60/0x330 fs/inode.c:2148 file_modified+0x24/0x34 fs/inode.c:2177 ext4_write_checks fs/ext4/file.c:264 [inline] ext4_buffered_write_iter+0x12c/0x294 fs/ext4/file.c:280 ext4_file_write_iter+0x84/0x408 fs/ext4/file.c:700 call_write_iter include/linux/fs.h:2199 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x2dc/0x46c fs/read_write.c:584 ksys_write+0xb4/0x160 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x24/0x34 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 -> #0 (&sb->s_type->i_mutex_key#8){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x1530/0x3084 kernel/locking/lockdep.c:5055 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5668 down_write+0x5c/0x88 kernel/locking/rwsem.c:1562 inode_lock include/linux/fs.h:756 [inline] ext4_xattr_inode_create fs/ext4/xattr.c:1453 [inline] ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1536 [inline] ext4_xattr_set_entry+0xdbc/0xe00 fs/ext4/xattr.c:1664 ext4_xattr_ibody_set+0x94/0x184 fs/ext4/xattr.c:2224 ext4_xattr_set_handle+0x648/0x9a0 fs/ext4/xattr.c:2381 ext4_xattr_set+0x100/0x1d0 fs/ext4/xattr.c:2495 ext4_xattr_trusted_set+0x4c/0x64 fs/ext4/xattr_trusted.c:38 __vfs_setxattr+0x250/0x260 fs/xattr.c:182 __vfs_setxattr_noperm+0xcc/0x320 fs/xattr.c:216 __vfs_setxattr_locked+0x16c/0x194 fs/xattr.c:277 vfs_setxattr+0xf4/0x1f4 fs/xattr.c:309 do_setxattr fs/xattr.c:594 [inline] setxattr fs/xattr.c:617 [inline] path_setxattr+0x354/0x414 fs/xattr.c:636 __do_sys_lsetxattr fs/xattr.c:659 [inline] __se_sys_lsetxattr fs/xattr.c:655 [inline] __arm64_sys_lsetxattr+0x2c/0x40 fs/xattr.c:655 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->xattr_sem); lock(&sb->s_type->i_mutex_key#8); lock(&ei->xattr_sem); lock(&sb->s_type->i_mutex_key#8); *** DEADLOCK *** 3 locks held by syz-executor.0/3668: #0: ffff0000c9dee460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x20/0x64 fs/namespace.c:393 #1: ffff0000cf16b3d0 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #1: ffff0000cf16b3d0 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0xd4/0x1f4 fs/xattr.c:308 #2: ffff0000cf16b098 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] #2: ffff0000cf16b098 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0xd0/0x9a0 fs/ext4/xattr.c:2308 stack backtrace: CPU: 1 PID: 3668 Comm: syz-executor.0 Not tainted 6.1.0-rc8-syzkaller-00172-ga5541c0811a0-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:163 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x2c4/0x2c8 kernel/locking/lockdep.c:2055 check_noncircular+0x14c/0x154 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x1530/0x3084 kernel/locking/lockdep.c:5055 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5668 down_write+0x5c/0x88 kernel/locking/rwsem.c:1562 inode_lock include/linux/fs.h:756 [inline] ext4_xattr_inode_create fs/ext4/xattr.c:1453 [inline] ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1536 [inline] ext4_xattr_set_entry+0xdbc/0xe00 fs/ext4/xattr.c:1664 ext4_xattr_ibody_set+0x94/0x184 fs/ext4/xattr.c:2224 ext4_xattr_set_handle+0x648/0x9a0 fs/ext4/xattr.c:2381 ext4_xattr_set+0x100/0x1d0 fs/ext4/xattr.c:2495 ext4_xattr_trusted_set+0x4c/0x64 fs/ext4/xattr_trusted.c:38 __vfs_setxattr+0x250/0x260 fs/xattr.c:182 __vfs_setxattr_noperm+0xcc/0x320 fs/xattr.c:216 __vfs_setxattr_locked+0x16c/0x194 fs/xattr.c:277 vfs_setxattr+0xf4/0x1f4 fs/xattr.c:309 do_setxattr fs/xattr.c:594 [inline] setxattr fs/xattr.c:617 [inline] path_setxattr+0x354/0x414 fs/xattr.c:636 __do_sys_lsetxattr fs/xattr.c:659 [inline] __se_sys_lsetxattr fs/xattr.c:655 [inline] __arm64_sys_lsetxattr+0x2c/0x40 fs/xattr.c:655 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584