features/shard: Fix crash during shards cleanup in error cases

A crash is seen during a reattempt to clean up shards in background
upon remount. And this happens even on remount (which means a remount
is no workaround for the crash).

In such a situation, the in-memory base inode object will not be
existent (new process, non-existent base shard).
So local->resolver_base_inode will be NULL.

In the event of an error (in this case, of space running out), the
process would crash at the time of logging the error in the following line -

        gf_msg(this->name, GF_LOG_ERROR, local->op_errno, SHARD_MSG_FOP_FAILED,
               "failed to delete shards of %s",
               uuid_utoa(local->resolver_base_inode->gfid));

Fixed that by using local->base_gfid as the source of gfid when
local->resolver_base_inode is NULL.

Change-Id: I0b49f2b58becd0d8874b3d4b14ff8d92a89d02d5
Fixes: #1127
Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>

1 files changed, 9 insertions, 2 deletions

diff --git a/xlators/features/shard/src/shard.c b/xlators/features/shard/src/shard.c
index c59e244429a..e4042117427 100644
--- a/xlators/features/shard/src/shard.c
+++ b/xlators/features/shard/src/shard.c
@@ -2939,13 +2939,20 @@ int
 shard_post_lookup_shards_unlink_handler(call_frame_t *frame, xlator_t *this)
 {
     shard_local_t *local = NULL;
+    uuid_t gfid = {
+        0,
+    };
 
     local = frame->local;
 
+    if (local->resolver_base_inode)
+        gf_uuid_copy(gfid, local->resolver_base_inode->gfid);
+    else
+        gf_uuid_copy(gfid, local->base_gfid);
+
     if ((local->op_ret < 0) && (local->op_errno != ENOENT)) {
         gf_msg(this->name, GF_LOG_ERROR, local->op_errno, SHARD_MSG_FOP_FAILED,
-               "failed to delete shards of %s",
-               uuid_utoa(local->resolver_base_inode->gfid));
+               "failed to delete shards of %s", uuid_utoa(gfid));
         return 0;
     }
     local->op_ret = 0;