This fix was nacked by Philip, for reasons identified in the email linked
below.
Link: https://lkml.kernel.org/r/68f15d67-8945-2728-1f17-5b53a80ec52d@squashfs.org.uk
Fixes: 72e544b1b28325 ("squashfs: harden sanity check in squashfs_read_xattr_id_table")
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Fedor Pchelkin <pchelkin@ispras.ru>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
        /* Sanity check values */
 
        /* there is always at least one xattr id */
-       if (*xattr_ids <= 0)
+       if (*xattr_ids == 0)
                return ERR_PTR(-EINVAL);
 
        len = SQUASHFS_XATTR_BLOCK_BYTES(*xattr_ids);