nfsd4: reject "negative" acl lengths
commit 64a817cfbded8674f345d1117b117f942a351a69 upstream.
Since we only enforce an upper bound, not a lower bound, a "negative"
length can get through here.
The symptom seen was a warning when we attempt to a kmalloc with an
excessive size.
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 967d68e..ace6745 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -263,7 +263,7 @@
iattr->ia_valid |= ATTR_SIZE;
}
if (bmval[0] & FATTR4_WORD0_ACL) {
- int nace;
+ u32 nace;
struct nfs4_ace *ace;
READ_BUF(4); len += 4;