Re: [PATCH] ext2: ensure link targets are NULL-terminated

From: Matthew Wilcox
Date: Thu Dec 11 2008 - 14:48:42 EST


On Thu, Dec 11, 2008 at 07:16:28PM +0000, Duane Griffin wrote:
> Ensure link targets are NULL-terminated, even if corrupted on-disk.

FWIW, that's spelled 'NUL' -- NULL is a pointer value, NUL is an ASCII
code.

> Signed-off-by: Duane Griffin <duaneg@xxxxxxxxx>
> ---
> fs/ext2/symlink.c | 4 +++-
> 1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/fs/ext2/symlink.c b/fs/ext2/symlink.c
> index 4e2426e..9b164ba 100644
> --- a/fs/ext2/symlink.c
> +++ b/fs/ext2/symlink.c
> @@ -24,7 +24,9 @@
> static void *ext2_follow_link(struct dentry *dentry, struct nameidata *nd)
> {
> struct ext2_inode_info *ei = EXT2_I(dentry->d_inode);
> - nd_set_link(nd, (char *)ei->i_data);
> + char *link = (char *) ei->i_data;
> + link[sizeof(ei->i_data) - 1] = '\0';
> + nd_set_link(nd, link);
> return NULL;
> }
>
> --
> 1.6.0.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html

--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/