File 0005-LU-0000-nodemap-avoid-NULL-deref.patch of Package lustre_2_15

From 662539c39c7977771e40d08d2402d6ed94aced77 Mon Sep 17 00:00:00 2001
From: Mr NeilBrown <neilb@suse.de>
Date: Wed, 30 Nov 2022 10:03:00 +1100
Subject: [PATCH 05/30] LU-0000 nodemap: avoid NULL deref

Setting ncf_obj to NULL can cause null-pointer-deref, especially if we
get a failure and leave it there.

Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: I04988eaef49fcb8304fe27b91b29e4a09b8ca15e
---
 lustre/ptlrpc/nodemap_storage.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/lustre/ptlrpc/nodemap_storage.c b/lustre/ptlrpc/nodemap_storage.c
index de60d0f5e649..f86ed9669399 100644
--- a/lustre/ptlrpc/nodemap_storage.c
+++ b/lustre/ptlrpc/nodemap_storage.c
@@ -1133,16 +1133,14 @@ static void nodemap_save_all_caches(void)
 		struct obd_device *obd = ncf->ncf_obj->do_lu.lo_dev->ld_obd;
 		struct dt_object *o;
 
-		/* put current config file so save conf can rewrite it */
-		dt_object_put_nocache(&env, ncf->ncf_obj);
-		ncf->ncf_obj = NULL;
-
 		o = nodemap_save_config_cache(&env, dev, ncf->ncf_los);
 		if (IS_ERR(o))
-			CWARN("%s: error writing to nodemap config: rc = %d\n",
-			      obd->obd_name, rc);
-		else
+			CWARN("%s: error writing to nodemap config: rc = %ld\n",
+			      obd->obd_name, PTR_ERR(o));
+		else {
+			dt_object_put_nocache(&env, ncf->ncf_obj);
 			ncf->ncf_obj = o;
+		}
 	}
 	mutex_unlock(&ncf_list_lock);
 
-- 
2.38.1