yasm: patch CVE-2021-33456

Details: https://nvd.nist.gov/vuln/detail/CVE-2021-33465

The patch was taken from Debian:
https://sources.debian.org/patches/yasm/1.3.0-8/1020-hash-null-CVE-2021-33456.patch/

Signed-off-by: Gyorgy Sarvari <skandigraun@gmail.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-devtools/yasm/yasm/CVE-2021-33456.patch

@@ -0,0 +1,35 @@
+From 1126140b8f5ece18c58640725f0e4c08e5ec97b0 Mon Sep 17 00:00:00 2001
+From: Gyorgy Sarvari <skandigraun@gmail.com>
+Date: Sat, 15 Nov 2025 13:34:15 +0100
+Subject: [PATCH] A potential null pointer difference is that the return value
+ of the hash may be null. This fixes CVE-2021-33456.
+
+From: lixuebing <lixuebing@cqsoftware.com.cn>
+Date: Mon, 25 Aug 2025 13:51:28 +0800
+Subject: Fix null-pointer-dereference in hash
+Bug: https://github.com/yasm/yasm/issues/175
+Origin: https://github.com/yasm/yasm/pull/290
+
+CVE: CVE-2021-33456
+Upstream-Status: Submitted [https://github.com/yasm/yasm/pull/290]
+
+Signed-off-by: Gyorgy Sarvari <skandigraun@gmail.com>
+---
+ modules/preprocs/nasm/nasm-pp.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/modules/preprocs/nasm/nasm-pp.c b/modules/preprocs/nasm/nasm-pp.c
+index f9f92dd1..473d98c1 100644
+--- a/modules/preprocs/nasm/nasm-pp.c
++++ b/modules/preprocs/nasm/nasm-pp.c
+@@ -1102,6 +1102,10 @@ hash(char *s)
+ {
+     unsigned int h = 0;
+     unsigned int i = 0;
++    /* Check if the input string is NULL to avoid null pointer dereference */
++    if (s == NULL) {
++        return 0;
++    }
+     /*
+      * Powers of three, mod 31.
+      */

meta-oe/recipes-devtools/yasm/yasm_git.bb

@@ -16,6 +16,7 @@ SRC_URI = "git://github.com/yasm/yasm.git;branch=master;protocol=https \
            file://0001-bitvect-fix-build-with-gcc-15.patch \
            file://CVE-2023-29579.patch \
            file://CVE-2021-33464.patch \
+           file://CVE-2021-33456.patch \
            "