From 341d75642ecc4e27bc6fecb56eb98a0ba03d8544 Mon Sep 17 00:00:00 2001
From: Krutika Dhananjay <kdhananj@redhat.com>
Date: Mon, 23 Mar 2020 11:47:10 +0530
Subject: [PATCH 376/379] features/shard: Fix crash during shards cleanup in
 error cases

Backport of:
> https://review.gluster.org/c/glusterfs/+/24244
> Change-Id: I0b49f2b58becd0d8874b3d4b14ff8d92a89d02d5
> Fixes: #1127
> Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>

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
BUG: 1836233
Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>
Reviewed-on: https://code.engineering.redhat.com/gerrit/200689
Tested-by: RHGS Build Bot <nigelb@redhat.com>
Reviewed-by: Sunil Kumar Heggodu Gopala Acharya <sheggodu@redhat.com>
---
 xlators/features/shard/src/shard.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/xlators/features/shard/src/shard.c b/xlators/features/shard/src/shard.c
index 9ed597b..ee38ed2 100644
--- a/xlators/features/shard/src/shard.c
+++ b/xlators/features/shard/src/shard.c
@@ -2729,13 +2729,20 @@ int shard_unlink_shards_do(call_frame_t *frame, xlator_t *this, inode_t *inode);
 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;
-- 
1.8.3.1