[PATCH 5.17 0058/1126] NFSD: prevent integer overflow on 32 bit systems

Greg Kroah-Hartman
2022-04-05T07:50:23Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 23a9dbbe0faf124fc4c139615633b9d12a3a89ef upstream.

On a 32 bit system, the "len * sizeof(*p)" operation can have an
integer overflow.

Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/sunrpc/xdr.h | 2 ++
1 file changed, 2 insertions(+)

--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -731,6 +731,8 @@ xdr_stream_decode_uint32_array(struct xd

if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
return -EBADMSG;
+ if (len > SIZE_MAX / sizeof(*p))
+ return -EBADMSG;
p = xdr_inline_decode(xdr, len * sizeof(*p));
if (unlikely(!p))
return -EBADMSG;