Messages in this thread Patch in this message | | | Date | Fri, 22 Oct 2010 11:34:56 -0700 | From | Greg KH <> | Subject | [29/66] ocfs2: Dont walk off the end of fast symlinks. |
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2.6.32-stable review patch. If anyone has any objections, please let us know.
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From: Joel Becker <joel.becker@oracle.com>
commit 1fc8a117865b54590acd773a55fbac9221b018f0 upstream.
ocfs2 fast symlinks are NUL terminated strings stored inline in the inode data area. However, disk corruption or a local attacker could, in theory, remove that NUL. Because we're using strlen() (my fault, introduced in a731d1 when removing vfs_follow_link()), we could walk off the end of that string.
Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- fs/ocfs2/symlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/ocfs2/symlink.c +++ b/fs/ocfs2/symlink.c @@ -128,7 +128,7 @@ static void *ocfs2_fast_follow_link(stru } /* Fast symlinks can't be large */ - len = strlen(target); + len = strnlen(target, ocfs2_fast_symlink_chars(inode->i_sb)); link = kzalloc(len + 1, GFP_NOFS); if (!link) { status = -ENOMEM;
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