svcrdma: Clean up svc_rdma_build_read_chunk()
Dan Carpenter <dan.carpenter@oracle.com> observed that the while()
loop in svc_rdma_build_read_chunk() does not document the assumption
that the loop interior is always executed at least once.
Defensive: the function now returns -EINVAL if this assumption
fails.
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
index 933f79b..1f34fae 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_rw.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -660,19 +660,21 @@ static int svc_rdma_build_read_segment(struct svc_rdma_read_info *info,
return -EIO;
}
+/* Walk the segments in the Read chunk starting at @p and construct
+ * RDMA Read operations to pull the chunk to the server.
+ */
static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp,
struct svc_rdma_read_info *info,
__be32 *p)
{
int ret;
+ ret = -EINVAL;
info->ri_chunklen = 0;
- while (*p++ != xdr_zero) {
+ while (*p++ != xdr_zero && be32_to_cpup(p++) == info->ri_position) {
u32 rs_handle, rs_length;
u64 rs_offset;
- if (be32_to_cpup(p++) != info->ri_position)
- break;
rs_handle = be32_to_cpup(p++);
rs_length = be32_to_cpup(p++);
p = xdr_decode_hyper(p, &rs_offset);