linux-kernel - [PATCH v2] kasan: fix mention for KASAN_HW

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]

Date:   Fri, 23 Jun 2023 16:58:05 +0900
From:   Chanho Min <chanho.min@....com>
To:     andreyknvl@...il.com
Cc:     chanho.min@....com, dvyukov@...gle.com, elver@...gle.com,
        glider@...gle.com, gunho.lee@....com, kasan-dev@...glegroups.com,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        ryabinin.a.a@...il.com, vincenzo.frascino@....com
Subject: [PATCH v2] kasan: fix mention for KASAN_HW_TAGS

This patch fixes description of the KASAN_HW_TAGS's memory consumption.
KASAN_HW_TAGS are dependent on the HW implementation and are not reserved
from system memory like shadow memory.

Suggested-by: Andrey Konovalov <andreyknvl@...il.com>
Signed-off-by: Chanho Min <chanho.min@....com>
---
 lib/Kconfig.kasan | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index fdca89c05745..f8f9e12510b7 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -124,7 +124,8 @@ config KASAN_HW_TAGS
 	  Supported only on arm64 CPUs starting from ARMv8.5 and relies on
 	  Memory Tagging Extension and Top Byte Ignore.
 
-	  Consumes about 1/32nd of available memory.
+	  Does not consume memory by itself but relies on the 1/32nd of
+	  available memory being reserved by the firmware when MTE is enabled.
 
 	  May potentially introduce problems related to pointer casting and
 	  comparison, as it embeds a tag into the top byte of each pointer.
-- 
2.17.1