[BUG] WARNING in ext4_journalled_invalidate_folio

[Farhad Alemi]

Hello,

As part of the kernel research at ASU's SEFCOM
lab, we hit the crash below. Crash reports can be found here:

  https://github.com/farhad-alemi/public_bug_reports/tree/main/172-warning-in-ext4-journalled-invalidate-folio/

  __ext4_journalled_invalidate_folio(folio, offset, length) < 0
  WARNING: fs/ext4/inode.c:3432 at
ext4_journalled_invalidate_folio+0x4a/0x50 fs/ext4/inode.c:3432,
CPU#0: syz.3.369/14887
  RIP: 0010:ext4_journalled_invalidate_folio+0x4a/0x50 fs/ext4/inode.c:3432
  Call Trace:
   ext4_journalled_invalidate_folio+0x4a/0x50 fs/ext4/inode.c:3432
   folio_invalidate mm/truncate.c:140 [inline]
   truncate_inode_partial_folio+0x33e/0x8d0 mm/truncate.c:249
   truncate_inode_pages_range+0x5de/0xdf0 mm/truncate.c:416
   ext4_truncate_failed_write fs/ext4/truncate.h:21 [inline]
   ext4_journalled_write_end+0x8f2/0xc70 fs/ext4/inode.c:1608
   generic_perform_write+0x611/0x8d0 mm/filemap.c:4346
   ext4_buffered_write_iter+0xce/0x3a0 fs/ext4/file.c:316
   ext4_file_write_iter+0x298/0x1bf0
   vfs_write+0x6f3/0xda0 fs/read_write.c:688

Our reproducer.c is available upon request.

Happy to test a patch if that would help.

Regards,