rpcsvc: Fix memory corruption caused by rpcsvc_dump returning non-zero

The convention followed is that any actor should return non-zero
value only if it has not attempted to send the reply back. If an
actor returns non-zero, rpcsvc_handle_rpc_call tries to send an
error reply. Since, rpcsvc_submit_generic frees the rpc_req, its wrong
to invoke it more than once on same rpc_req. When the transport is not
connected, rpcsvc_dump used to pass the non-zero value it got from
 transport to rpcsvc resulting in memory corruption. Hence this patch
makes rpcsvc_dump to return 0.

Change-Id: I1b6f28969ee546c44d193d3d33debccb65585b69
BUG: 903113
Signed-off-by: Raghavendra G <raghavendra@gluster.com>
Reviewed-on: http://review.gluster.org/4183
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>
Reviewed-by: Raghavendra Bhat <raghavendra@redhat.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

1 files changed, 8 insertions, 10 deletions

diff --git a/rpc/rpc-lib/src/rpcsvc.c b/rpc/rpc-lib/src/rpcsvc.c
index bb14f11be..205ef1a9d 100644
--- a/rpc/rpc-lib/src/rpcsvc.c
+++ b/rpc/rpc-lib/src/rpcsvc.c
@@ -1729,15 +1729,17 @@ rpcsvc_dump (rpcsvc_request_t *req)
         uint32_t     dump_rsp_len      = 0;
 
         if (!req)
-                goto fail;
+                goto sendrsp;
 
         ret = build_prog_details (req, &rsp);
         if (ret < 0) {
                 op_errno = -ret;
-                goto fail;
+                goto sendrsp;
         }
 
-fail:
+        op_errno = 0;
+
+sendrsp:
         rsp.op_errno = gf_errno_to_error (op_errno);
         rsp.op_ret   = ret;
 
@@ -1749,15 +1751,11 @@ fail:
 
         ret = xdr_serialize_generic (iov, &rsp, (xdrproc_t)xdr_gf_dump_rsp);
         if (ret < 0) {
-                if (req)
-                        req->rpc_err = GARBAGE_ARGS;
-                op_errno = EINVAL;
-                goto fail;
+                ret = RPCSVC_ACTOR_ERROR;
+        } else {
+                rpcsvc_submit_generic (req, &iov, 1, NULL, 0, NULL);
         }
 
-        ret = rpcsvc_submit_generic (req, &iov, 1, NULL, 0,
-                                     NULL);
-
         free_prog_details (&rsp);
 
         return ret;