lkml.org 
[lkml]   [2022]   [Aug]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] ntfs: Ensure $Extend is a directory
On Tue, Jul 26, 2022 at 05:15:13PM -0700, Soumya Negi wrote:
> Fix Syzbot bug: kernel BUG in ntfs_lookup_inode_by_name
> https://syzkaller.appspot.com/bug?id=32cf53b48c1846ffc25a185a2e92e170d1a95d71
>
> Check whether $Extend is a directory or not( for NTFS3.0+) while
> loading system files. If it isn't(as in the case of this bug where the
> mft record for $Extend contains a regular file), load_system_files()
> returns false.
>
> Reported-by: syzbot+30b7f850c6d98ea461d2@syzkaller.appspotmail.com
> CC: stable@vger.kernel.org # 4.9+
> Signed-off-by: Soumya Negi <soumya.negi97@gmail.com>
> ---
> Changes since v1:
> * Added CC tag for stable
> * Formatted changelog to fit within 72 cols
>
> ---
> fs/ntfs/super.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
> index 5ae8de09b271..18e2902531f9 100644
> --- a/fs/ntfs/super.c
> +++ b/fs/ntfs/super.c
> @@ -2092,10 +2092,15 @@ static bool load_system_files(ntfs_volume *vol)
> // TODO: Initialize security.
> /* Get the extended system files' directory inode. */
> vol->extend_ino = ntfs_iget(sb, FILE_Extend);
> - if (IS_ERR(vol->extend_ino) || is_bad_inode(vol->extend_ino)) {
> + if (IS_ERR(vol->extend_ino) || is_bad_inode(vol->extend_ino) ||
> + !S_ISDIR(vol->extend_ino->i_mode)) {
> + static const char *es1 = "$Extend is not a directory";
> + static const char *es2 = "Failed to load $Extend";
> + const char *es = !S_ISDIR(vol->extend_ino->i_mode) ? es1 : es2;
> +
> if (!IS_ERR(vol->extend_ino))
> iput(vol->extend_ino);
> - ntfs_error(sb, "Failed to load $Extend.");
> + ntfs_error(sb, "%s.", es);
> goto iput_sec_err_out;
> }
> #ifdef NTFS_RW
> --
> 2.17.1

Hi Anton,
Have you had a chance to look at this patch?

Thanks,
Soumya

\
 
 \ /
  Last update: 2022-08-29 17:04    [W:0.052 / U:0.388 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site