Re: [PATCH 4.19 5.4 5.10] nilfs2: propagate directory read errors from nilfs_find_entry()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sun, Oct 20, 2024 at 12:21:15AM +0900, Ryusuke Konishi wrote:
> commit 08cfa12adf888db98879dbd735bc741360a34168 upstream.
> 
> Syzbot reported that a task hang occurs in vcs_open() during a fuzzing
> test for nilfs2.
> 
> The root cause of this problem is that in nilfs_find_entry(), which
> searches for directory entries, ignores errors when loading a directory
> page/folio via nilfs_get_folio() fails.
> 
> If the filesystem images is corrupted, and the i_size of the directory
> inode is large, and the directory page/folio is successfully read but
> fails the sanity check, for example when it is zero-filled,
> nilfs_check_folio() may continue to spit out error messages in bursts.
> 
> Fix this issue by propagating the error to the callers when loading a
> page/folio fails in nilfs_find_entry().
> 
> The current interface of nilfs_find_entry() and its callers is outdated
> and cannot propagate error codes such as -EIO and -ENOMEM returned via
> nilfs_find_entry(), so fix it together.
> 
> Link: https://lkml.kernel.org/r/20241004033640.6841-1-konishi.ryusuke@gmail.com
> Fixes: 2ba466d74ed7 ("nilfs2: directory entry operations")
> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
> Reported-by: Lizhi Xu <lizhi.xu@windriver.com>
> Closes: https://lkml.kernel.org/r/20240927013806.3577931-1-lizhi.xu@windriver.com
> Reported-by: syzbot+8a192e8d090fa9a31135@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=8a192e8d090fa9a31135
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
> Please apply this patch to the stable trees indicated by the subject
> prefix instead of the failed patches.
> 
> This patch is tailored to take page/folio conversion into account and
> avoid a few conflicts.  Compiled and tested successfully.

All now queued up, thanks for the backports.

greg k-h