cluster: fix crash on link of named pipe in stripe/replicate vol

A crash occurs when attempting to link a named pipe on a striped,
replicated volume. The cause for this crash is attempting to deref
a NULL inode pointer in stripe_link_cbk(). The RCA for this bug
uncovered a couple of problems:

- AFR ignores the inode pointer it receives on failure (returning
  NULL).
- stripe assumes the inode pointer is valid on failure.

Either one of these changes addresses the crash, but this patch
includes both changes. AFR is modified to pass along the inode
pointer it receives (which could still be NULL). stripe is
modified to not assume the inode pointer is valid on fop failure.

BUG: 842825
Change-Id: I9cb2cc918552620929c3ecbd69bc66d4635eafdc
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-on: http://review.gluster.com/3727
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-by: Anand Avati <avati@redhat.com>

1 files changed, 10 insertions, 10 deletions

diff --git a/xlators/cluster/stripe/src/stripe.c b/xlators/cluster/stripe/src/stripe.c
index d17b2a9124e..e2176eeae66 100644
--- a/xlators/cluster/stripe/src/stripe.c
+++ b/xlators/cluster/stripe/src/stripe.c
@@ -1951,16 +1951,6 @@ stripe_link_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
         {
                 callcnt = --local->call_count;
 
-		if (IA_ISREG(inode->ia_type)) {
-			inode_ctx_get(inode, this, (uint64_t *) &fctx);
-			if (!fctx) {
-				gf_log(this->name, GF_LOG_ERROR,
-					"failed to get stripe context");
-				op_ret = -1;
-				op_errno = EINVAL;
-			}
-		}
-
                 if (op_ret == -1) {
                         gf_log (this->name, GF_LOG_DEBUG,
                                 "%s returned error %s",
@@ -1974,6 +1964,16 @@ stripe_link_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                 if (op_ret >= 0) {
                         local->op_ret = 0;
 
+			if (IA_ISREG(inode->ia_type)) {
+				inode_ctx_get(inode, this, (uint64_t *) &fctx);
+				if (!fctx) {
+					gf_log(this->name, GF_LOG_ERROR,
+						"failed to get stripe context");
+					op_ret = -1;
+					op_errno = EINVAL;
+				}
+			}
+
                         if (FIRST_CHILD(this) == prev->this) {
                                 local->inode      = inode_ref (inode);
                                 local->stbuf      = *buf;