linux-kernel - [PATCH 3/3] mm/vmalloc: Print a warning message first on failure

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210516202056.2120-4-urezki@gmail.com>
Date:   Sun, 16 May 2021 22:20:56 +0200
From:   "Uladzislau Rezki (Sony)" <urezki@...il.com>
To:     Andrew Morton <akpm@...ux-foundation.org>
Cc:     linux-mm@...ck.org, LKML <linux-kernel@...r.kernel.org>,
        Mel Gorman <mgorman@...e.de>,
        Matthew Wilcox <willy@...radead.org>,
        Nicholas Piggin <npiggin@...il.com>,
        Uladzislau Rezki <urezki@...il.com>,
        Hillf Danton <hdanton@...a.com>,
        Michal Hocko <mhocko@...e.com>,
        Oleksiy Avramchenko <oleksiy.avramchenko@...ymobile.com>,
        Steven Rostedt <rostedt@...dmis.org>
Subject: [PATCH 3/3] mm/vmalloc: Print a warning message first on failure

When a memory allocation for array of pages are not succeed
emit a warning message as a first step and then perform the
further cleanup.

The reason it should be done in a right order is the clean
up function which is free_vm_area() can potentially also
follow its error paths what can lead to confusion what was
broken first.

Signed-off-by: Uladzislau Rezki (Sony) <urezki@...il.com>
---
 mm/vmalloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index a8e50278019a..b2a0cbfa37c1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2781,11 +2781,11 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 	}
 
 	if (!area->pages) {
-		free_vm_area(area);
 		warn_alloc(gfp_mask, NULL,
 			   "vmalloc size %lu allocation failure: "
 			   "page array size %lu allocation failed",
 			   nr_small_pages * PAGE_SIZE, array_size);
+		free_vm_area(area);
 		return NULL;
 	}
 
-- 
2.20.1