diff options
-rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index ae3fb9bc8a21..292022f0976e 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -493,7 +493,13 @@ static bool xdr_check_write_chunk(struct svc_rdma_recv_ctxt *rctxt) if (xdr_stream_decode_u32(&rctxt->rc_stream, &segcount)) return false; - /* A bogus segcount causes this buffer overflow check to fail. */ + /* Before trusting the segcount value enough to use it in + * a computation, perform a simple range check. This is an + * arbitrary but sensible limit (ie, not architectural). + */ + if (unlikely(segcount > RPCSVC_MAXPAGES)) + return false; + p = xdr_inline_decode(&rctxt->rc_stream, segcount * rpcrdma_segment_maxsz * sizeof(*p)); return p != NULL; |