yasm: fix CVE-2023-37732

Yasm v1.3.0.78 was found prone to NULL Pointer Dereference in /libyasm/intnum.c
and /elf/elf.c, which allows the attacker to cause a denial of service via a
crafted file.

References:
https://github.com/yasm/yasm/issues/233
https://nvd.nist.gov/vuln/detail/CVE-2023-37732

Signed-off-by: Soumya <soumya.sambu@windriver.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

meta-oe/recipes-devtools/yasm/yasm/CVE-2023-37732.patch

@@ -0,0 +1,41 @@
+From 2cd3bb50e256f5ed5f611ac611d25fe673f2cec3 Mon Sep 17 00:00:00 2001
+From: Peter Johnson <johnson.peter@gmail.com>
+Date: Fri, 11 Aug 2023 10:49:51 +0000
+Subject: [PATCH] elf.c: Fix NULL deref on bad xsize expression (#234)
+
+CVE: CVE-2023-37732
+
+Upstream-Status: Backport [https://github.com/yasm/yasm/commit/2cd3bb50e256f5ed5f611ac611d25fe673f2cec3]
+
+Signed-off-by: Soumya <soumya.sambu@windriver.com>
+---
+ modules/objfmts/elf/elf.c | 10 +++++-----
+ 1 file changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/modules/objfmts/elf/elf.c b/modules/objfmts/elf/elf.c
+index 2486bba8..bab4c9ca 100644
+--- a/modules/objfmts/elf/elf.c
++++ b/modules/objfmts/elf/elf.c
+@@ -482,15 +482,15 @@ elf_symtab_write_to_file(FILE *f, elf_symtab_head *symtab,
+
+         /* get size (if specified); expr overrides stored integer */
+         if (entry->xsize) {
+-            size_intn = yasm_intnum_copy(
+-                yasm_expr_get_intnum(&entry->xsize, 1));
+-            if (!size_intn) {
++            yasm_intnum *intn = yasm_expr_get_intnum(&entry->xsize, 1);
++            if (!intn) {
+                 yasm_error_set(YASM_ERROR_VALUE,
+                                N_("size specifier not an integer expression"));
+                 yasm_errwarn_propagate(errwarns, entry->xsize->line);
+-            }
++            } else
++                size_intn = yasm_intnum_copy(intn);
+         }
+-        else
++        if (!size_intn)
+             size_intn = yasm_intnum_create_uint(entry->size);
+
+         /* get EQU value for constants */
+--
+2.40.0

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

@@ -13,6 +13,7 @@ SRCREV = "ba463d3c26c0ece2e797b8d6381b161633b5971a"
 SRC_URI = "git://github.com/yasm/yasm.git;branch=master;protocol=https \
            file://0001-Do-not-use-AC_HEADER_STDC.patch \
            file://CVE-2023-31975.patch \
+           file://CVE-2023-37732.patch \
 "
 
 S = "${WORKDIR}/git"