commit 41e192ad2779cae0102879612dfe46726e4396aa upstream.
Syzbot reported that in directory operations after nilfs2 detects
filesystem corruption and degrades to read-only,
__block_write_begin_int(), which is called to prepare block writes, may
fail the BUG_ON check for accesses exceeding the folio/page size,
triggering a kernel bug.
This was found to be because the "checked" flag of a page/folio was not
cleared when it was discarded by nilfs2's own routine, which causes the
sanity check of directory entries to be skipped when the directory
page/folio is reloaded. So, fix that.
This was necessary when the use of nilfs2's own page discard routine was
applied to more than just metadata files.
Link: https://lkml.kernel.org/r/20241017193359.5051-1-konishi.ryusuke@gmail.com
Fixes: 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+d6ca2daf692c7a82f959@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d6ca2daf692c7a82f959
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6ed469df0bfbef3e4b44fca954a781919db9f7ab upstream.
Syzbot reported that after nilfs2 reads a corrupted file system image
and degrades to read-only, the BUG_ON check for the buffer delay flag
in submit_bh_wbc() may fail, causing a kernel bug.
This is because the buffer delay flag is not cleared when clearing the
buffer state flags to discard a page/folio or a buffer head. So, fix
this.
This became necessary when the use of nilfs2's own page clear routine
was expanded. This state inconsistency does not occur if the buffer
is written normally by log writing.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Link: https://lore.kernel.org/r/20241015213300.7114-1-konishi.ryusuke@gmail.com
Fixes: 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption")
Reported-by: syzbot+985ada84bf055a575c07@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=985ada84bf055a575c07
Cc: stable@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
