syzbot


possible deadlock in attr_collapse_range

Status: upstream: reported on 2024/05/28 05:27
Subsystems: ntfs3
[Documentation on labels]
Reported-by: syzbot+66feeab2e2b600100de0@syzkaller.appspotmail.com
First crash: 22d, last: 22d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ntfs3?] possible deadlock in attr_collapse_range 0 (1) 2024/05/28 05:27

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.9.0-syzkaller-10323-g8f6a15f095a6 #0 Not tainted
------------------------------------------------------
syz-executor.1/19565 is trying to acquire lock:
ffff88805b5bf7b0 (&ni->file.run_lock#3){++++}-{3:3}, at: attr_collapse_range+0x3be/0x1400 fs/ntfs3/attrib.c:1894

but task is already holding lock:
ffff88805b5bf700 (&ni->ni_lock#2/4){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1123 [inline]
ffff88805b5bf700 (&ni->ni_lock#2/4){+.+.}-{3:3}, at: ntfs_fallocate+0x9af/0x1120 fs/ntfs3/file.c:556

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ni->ni_lock#2/4){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       ni_lock fs/ntfs3/ntfs_fs.h:1123 [inline]
       ntfs_fallocate+0x9af/0x1120 fs/ntfs3/file.c:556
       vfs_fallocate+0x4b8/0xfb0 fs/open.c:330
       ksys_fallocate fs/open.c:353 [inline]
       __do_sys_fallocate fs/open.c:361 [inline]
       __se_sys_fallocate fs/open.c:359 [inline]
       __x64_sys_fallocate+0xd5/0x140 fs/open.c:359
       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

-> #2 (mapping.invalidate_lock#4){++++}-{3:3}:
       down_read+0x9a/0x330 kernel/locking/rwsem.c:1526
       filemap_invalidate_lock_shared include/linux/fs.h:846 [inline]
       filemap_fault+0x275/0x2610 mm/filemap.c:3301
       __do_fault+0x10a/0x490 mm/memory.c:4562
       do_read_fault mm/memory.c:4926 [inline]
       do_fault mm/memory.c:5056 [inline]
       do_pte_missing mm/memory.c:3903 [inline]
       handle_pte_fault mm/memory.c:5380 [inline]
       __handle_mm_fault+0x39e2/0x53f0 mm/memory.c:5523
       handle_mm_fault+0x476/0xa00 mm/memory.c:5688
       do_user_addr_fault+0x2e5/0xe50 arch/x86/mm/fault.c:1389
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
       rep_movs_alternative+0x30/0x70 arch/x86/lib/copy_user_64.S:50
       copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline]
       raw_copy_from_user arch/x86/include/asm/uaccess_64.h:125 [inline]
       _copy_from_user+0xc6/0xf0 lib/usercopy.c:23
       copy_from_user include/linux/uaccess.h:183 [inline]
       get_user_ifreq+0xf1/0x250 net/socket.c:3346
       sock_do_ioctl+0x16c/0x280 net/socket.c:1234
       sock_ioctl+0x22e/0x6c0 net/socket.c:1341
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:907 [inline]
       __se_sys_ioctl fs/ioctl.c:893 [inline]
       __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:893
       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 (&mm->mmap_lock){++++}-{3:3}:
       __might_fault mm/memory.c:6240 [inline]
       __might_fault+0x11b/0x190 mm/memory.c:6233
       _copy_to_user+0x2b/0xc0 lib/usercopy.c:36
       copy_to_user include/linux/uaccess.h:191 [inline]
       fiemap_fill_next_extent+0x232/0x390 fs/ioctl.c:145
       ni_fiemap+0x9eb/0xc10 fs/ntfs3/frecord.c:2044
       ntfs_fiemap+0xc9/0x120 fs/ntfs3/file.c:1206
       ioctl_fiemap fs/ioctl.c:220 [inline]
       do_vfs_ioctl+0x404/0x1ad0 fs/ioctl.c:841
       __do_sys_ioctl fs/ioctl.c:905 [inline]
       __se_sys_ioctl fs/ioctl.c:893 [inline]
       __x64_sys_ioctl+0x116/0x220 fs/ioctl.c:893
       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

-> #0 (&ni->file.run_lock#3){++++}-{3:3}:
       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
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1579
       attr_collapse_range+0x3be/0x1400 fs/ntfs3/attrib.c:1894
       ntfs_fallocate+0x9c9/0x1120 fs/ntfs3/file.c:557
       vfs_fallocate+0x4b8/0xfb0 fs/open.c:330
       ksys_fallocate fs/open.c:353 [inline]
       __do_sys_fallocate fs/open.c:361 [inline]
       __se_sys_fallocate fs/open.c:359 [inline]
       __x64_sys_fallocate+0xd5/0x140 fs/open.c:359
       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

other info that might help us debug this:

Chain exists of:
  &ni->file.run_lock#3 --> mapping.invalidate_lock#4 --> &ni->ni_lock#2/4

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ni->ni_lock#2/4);
                               lock(mapping.invalidate_lock#4);
                               lock(&ni->ni_lock#2/4);
  lock(
&ni->file.run_lock#3);

 *** DEADLOCK ***

4 locks held by syz-executor.1/19565:
 #0: ffff88807b294420 (sb_writers#17){.+.+}-{0:0}, at: ksys_fallocate fs/open.c:353 [inline]
 #0: ffff88807b294420 (sb_writers#17){.+.+}-{0:0}, at: __do_sys_fallocate fs/open.c:361 [inline]
 #0: ffff88807b294420 (sb_writers#17){.+.+}-{0:0}, at: __se_sys_fallocate fs/open.c:359 [inline]
 #0: ffff88807b294420 (sb_writers#17){.+.+}-{0:0}, at: __x64_sys_fallocate+0xd5/0x140 fs/open.c:359
 #1: ffff88805b5bf9a0 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
 #1: ffff88805b5bf9a0 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: ntfs_fallocate+0x2ac/0x1120 fs/ntfs3/file.c:472
 #2: ffff88805b5bfb40 (mapping.invalidate_lock#4){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:836 [inline]
 #2: ffff88805b5bfb40 (mapping.invalidate_lock#4){++++}-{3:3}, at: ntfs_fallocate+0x6fb/0x1120 fs/ntfs3/file.c:486
 #3: ffff88805b5bf700 (&ni->ni_lock#2/4
){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1123 [inline]
){+.+.}-{3:3}, at: ntfs_fallocate+0x9af/0x1120 fs/ntfs3/file.c:556

stack backtrace:
CPU: 0 PID: 19565 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-10323-g8f6a15f095a6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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
 down_write+0x3a/0x50 kernel/locking/rwsem.c:1579
 attr_collapse_range+0x3be/0x1400 fs/ntfs3/attrib.c:1894
 ntfs_fallocate+0x9c9/0x1120 fs/ntfs3/file.c:557
 vfs_fallocate+0x4b8/0xfb0 fs/open.c:330
 ksys_fallocate fs/open.c:353 [inline]
 __do_sys_fallocate fs/open.c:361 [inline]
 __se_sys_fallocate fs/open.c:359 [inline]
 __x64_sys_fallocate+0xd5/0x140 fs/open.c:359
 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
RIP: 0033:0x7f2890c7cee9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2891a740c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f2890dabf80 RCX: 00007f2890c7cee9
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000008
RBP: 00007f2890cc949e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000007000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f2890dabf80 R15: 00007ffefad699c8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/24 05:20 upstream 8f6a15f095a6 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root possible deadlock in attr_collapse_range
* Struck through repros no longer work on HEAD.