linux-kernel - [PATCH] mm: slub: Fix slub_debug disablement for list of slabs

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-next>] [day] [month] [year] [list]

Message-Id: <1626176750-13099-1-git-send-email-vjitta@codeaurora.org>
Date:   Tue, 13 Jul 2021 17:15:50 +0530
From:   vjitta@...eaurora.org
To:     cl@...ux.com, penberg@...nel.org, rientjes@...gle.com,
        iamjoonsoo.kim@....com, akpm@...ux-foundation.org, vbabka@...e.cz
Cc:     linux-mm@...ck.org, linux-kernel@...r.kernel.org,
        vinmenon@...eaurora.org, vjitta@...eaurora.org
Subject: [PATCH] mm: slub: Fix slub_debug disablement for list of slabs

From: Vijayanand Jitta <vjitta@...eaurora.org>

Consider the scenario where CONFIG_SLUB_DEBUG_ON is set
and we would want to disable slub_debug for few slabs.
Using boot parameter with slub_debug=-,slab_name syntax
doesn't work as expected i.e; only disabling debugging for
the specified list of slabs, instead it disables debugging
for all slabs. Fix this.

Signed-off-by: Vijayanand Jitta <vjitta@...eaurora.org>
---
 mm/slub.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index dc863c1..5a88418 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1429,6 +1429,7 @@ static int __init setup_slub_debug(char *str)
 	char *slab_list;
 	bool global_slub_debug_changed = false;
 	bool slab_list_specified = false;
+	bool slab_list_debug_disable = true;
 
 	slub_debug = DEBUG_DEFAULT_FLAGS;
 	if (*str++ != '=' || !*str)
@@ -1436,7 +1437,6 @@ static int __init setup_slub_debug(char *str)
 		 * No options specified. Switch on full debugging.
 		 */
 		goto out;
-
 	saved_str = str;
 	while (str) {
 		str = parse_slub_debug_flags(str, &flags, &slab_list, true);
@@ -1445,6 +1445,8 @@ static int __init setup_slub_debug(char *str)
 			slub_debug = flags;
 			global_slub_debug_changed = true;
 		} else {
+			if (flags || !IS_ENABLED(CONFIG_SLUB_DEBUG_ON))
+				slab_list_debug_disable = false;
 			slab_list_specified = true;
 		}
 	}
@@ -1456,7 +1458,7 @@ static int __init setup_slub_debug(char *str)
 	 * long as there is no option specifying flags without a slab list.
 	 */
 	if (slab_list_specified) {
-		if (!global_slub_debug_changed)
+		if (!global_slub_debug_changed && !slab_list_debug_disable)
 			slub_debug = 0;
 		slub_debug_string = saved_str;
 	}
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
2.7.4