syzbot

loop7: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
6.1.123-syzkaller #0 Not tainted
------------------------------------------------------
syz.7.1454/8651 is trying to acquire lock:
ffff88807e4ff958 (&mm->mmap_lock){++++}-{3:3}, at: internal_get_user_pages_fast+0x20b/0x2cf0 mm/gup.c:3031

but task is already holding lock:
ffff8880716f8b00 (&sb->s_type->i_mutex_key#33){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880716f8b00 (&sb->s_type->i_mutex_key#33){+.+.}-{3:3}, at: __blockdev_direct_IO+0x390/0x4810 fs/direct-io.c:1162

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#33){+.+.}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ntfs_file_mmap+0x583/0x7d0 fs/ntfs3/file.c:399
       call_mmap include/linux/fs.h:2270 [inline]
       mmap_file+0x5a/0xa0 mm/util.c:1109
       __mmap_region mm/mmap.c:2760 [inline]
       mmap_region+0x10b3/0x2660 mm/mmap.c:2904
       do_mmap+0x8c5/0xf60 mm/mmap.c:1424
       vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:520
       ksys_mmap_pgoff+0x4f5/0x6d0 mm/mmap.c:1470
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       internal_get_user_pages_fast+0x224/0x2cf0 mm/gup.c:3031
       __iov_iter_get_pages_alloc+0x3b1/0xa70 lib/iov_iter.c:1460
       iov_iter_get_pages2+0xcb/0x120 lib/iov_iter.c:1503
       dio_refill_pages fs/direct-io.c:172 [inline]
       dio_get_page fs/direct-io.c:215 [inline]
       do_direct_IO fs/direct-io.c:932 [inline]
       __blockdev_direct_IO+0x13d6/0x4810 fs/direct-io.c:1266
       blockdev_direct_IO include/linux/fs.h:3342 [inline]
       ntfs_direct_IO+0x193/0x360 fs/ntfs3/inode.c:800
       generic_file_read_iter+0x333/0x540 mm/filemap.c:2890
       call_read_iter include/linux/fs.h:2259 [inline]
       new_sync_read fs/read_write.c:389 [inline]
       vfs_read+0x88d/0xbf0 fs/read_write.c:470
       ksys_read+0x19c/0x2c0 fs/read_write.c:613
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#33);
                               lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#33);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

2 locks held by syz.7.1454/8651:
 #0: ffff88807da84868 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ba/0x360 fs/file.c:1031
 #1: ffff8880716f8b00 (&sb->s_type->i_mutex_key#33){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff8880716f8b00 (&sb->s_type->i_mutex_key#33){+.+.}-{3:3}, at: __blockdev_direct_IO+0x390/0x4810 fs/direct-io.c:1162

stack backtrace:
CPU: 0 PID: 8651 Comm: syz.7.1454 Not tainted 6.1.123-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 internal_get_user_pages_fast+0x224/0x2cf0 mm/gup.c:3031
 __iov_iter_get_pages_alloc+0x3b1/0xa70 lib/iov_iter.c:1460
 iov_iter_get_pages2+0xcb/0x120 lib/iov_iter.c:1503
 dio_refill_pages fs/direct-io.c:172 [inline]
 dio_get_page fs/direct-io.c:215 [inline]
 do_direct_IO fs/direct-io.c:932 [inline]
 __blockdev_direct_IO+0x13d6/0x4810 fs/direct-io.c:1266
 blockdev_direct_IO include/linux/fs.h:3342 [inline]
 ntfs_direct_IO+0x193/0x360 fs/ntfs3/inode.c:800
 generic_file_read_iter+0x333/0x540 mm/filemap.c:2890
 call_read_iter include/linux/fs.h:2259 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x88d/0xbf0 fs/read_write.c:470
 ksys_read+0x19c/0x2c0 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe711385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe712136038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fe711575fa0 RCX: 00007fe711385d29
RDX: 0000000000002000 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 00007fe711401b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe711575fa0 R15: 00007ffd05a5b048
 </TASK>