ceph: try to dump the msgs when decoding fails

[ Upstream commit 8b0da5c ]

When the msgs are corrupted we need to dump them and then it will
be easier to dig what has happened and where the issue is.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Milind Changire <mchangir@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

fs/ceph/mds_client.c

@@ -645,6 +645,7 @@ static int parse_reply_info(struct ceph_mds_session *s, struct ceph_msg *msg,
 	err = -EIO;
 out_bad:
 	pr_err("mds parse_reply err %d\n", err);
+	ceph_msg_dump(msg);
 	return err;
 }
 
@@ -3534,6 +3535,7 @@ static void handle_forward(struct ceph_mds_client *mdsc,
 
 bad:
 	pr_err("mdsc_handle_forward decode error err=%d\n", err);
+	ceph_msg_dump(msg);
 }
 
 static int __decode_session_metadata(void **p, void *end,
@@ -5254,6 +5256,7 @@ void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
 bad:
 	pr_err("error decoding fsmap %d. Shutting down mount.\n", err);
 	ceph_umount_begin(mdsc->fsc->sb);
+	ceph_msg_dump(msg);
 err_out:
 	mutex_lock(&mdsc->mutex);
 	mdsc->mdsmap_err = err;
@@ -5322,6 +5325,7 @@ void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
 bad:
 	pr_err("error decoding mdsmap %d. Shutting down mount.\n", err);
 	ceph_umount_begin(mdsc->fsc->sb);
+	ceph_msg_dump(msg);
 	return;
 }