Re: [PATCH v3] ntfs : fix shift-out-of-bounds in ntfs_iget

Greg KH
2023-08-10T17:32:13Z

On Thu, Aug 10, 2023 at 09:43:08PM +0530, Manas Ghandat wrote:
> Added a check to the compression_unit so that out of bound doesn't occur.

This probably needs more text to describe what is happening.

>
> Signed-off-by: Manas Ghandat <ghandatmanas@gmail.com>
> Reported-by: syzbot+4768a8f039aa677897d0@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=4768a8f039aa677897d0

What commit id does this fix? Should it go to stable kernels?

> ---
> V2 -> V3: Fix patching issue.
> V1 -> V2: Cleaned up coding style.
>
> fs/ntfs/inode.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
> index 6c3f38d66579..a657322874ed 100644
> --- a/fs/ntfs/inode.c
> +++ b/fs/ntfs/inode.c
> @@ -1077,6 +1077,15 @@ static int ntfs_read_locked_inode(struct inode *vi)
> goto unm_err_out;
> }
> if (a->data.non_resident.compression_unit) {
> + if (a->data.non_resident.compression_unit +
> + vol->cluster_size_bits > 32) {

Should be indented a bit left, right?

> + ntfs_error(vi->i_sb,
> + "Found non-standard compression unit (%u). Cannot handle this.",

Why all the extra ' ' characters?

thanks,

greg k-h