nasm: fix CVE-2018-10016

Previously fix of CVE-2018-10016 caused ovmf build failure,
I reported the failure to upstream and it replied with
this V2 fix.

Details at:
https://bugzilla.nasm.us/show_bug.cgi?id=3392473

(From OE-Core rev: e2fa6bc137faebba3c440cac93c88092421e8e82)

(From OE-Core rev: 19138a21aabe60b67015e3383f4030db0d4d37a4)

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 41 insertions, 0 deletions

diff --git a/meta/recipes-devtools/nasm/nasm/0001-eval-Eliminate-division-by-zero.patch b/meta/recipes-devtools/nasm/nasm/0001-eval-Eliminate-division-by-zero.patch
new file mode 100644
index 0000000000..6c332497c9
--- /dev/null
+++ b/meta/recipes-devtools/nasm/nasm/0001-eval-Eliminate-division-by-zero.patch
@@ -0,0 +1,40 @@
+From ceec0d818798aeaa75ed4907e6135b0247ed46b2 Mon Sep 17 00:00:00 2001
+From: Cyrill Gorcunov <gorcunov@gmail.com>
+Date: Sun, 14 Oct 2018 01:26:19 +0300
+Subject: [PATCH] eval: Eliminate division by zero
+
+When doing division we should detect if the value we're
+divided by is not zero. Instead of is_unknown() helper
+we should use is_just_unknown().
+
+https://bugzilla.nasm.us/show_bug.cgi?id=3392515
+https://bugzilla.nasm.us/show_bug.cgi?id=3392473
+
+Reported-by: Jun <jxx13@psu.edu>
+Reported-by: stuartly <situlingyun@gmail.com>
+Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
+
+Upstream-Status: Backport [https://github.com/netwide-assembler/nasm/commit/ceec0d818798aeaa75ed4907e6135b0247ed46b2.patch]
+CVE: CVE-2018-10016
+Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
+
+---
+ asm/eval.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/asm/eval.c b/asm/eval.c
+index 1a6680f..7e727a4 100644
+--- a/asm/eval.c
++++ b/asm/eval.c
+@@ -580,7 +580,7 @@ static expr *expr5(int critical)
+                   " scalar values");
+             return NULL;
+         }
+-        if (j != '*' && !is_unknown(f) && reloc_value(f) == 0) {
++        if (j != '*' && !is_just_unknown(f) && reloc_value(f) == 0) {
+             nasm_error(ERR_NONFATAL, "division by zero");
+             return NULL;
+         }
+-- 
+2.10.2
+
diff --git a/meta/recipes-devtools/nasm/nasm_2.13.03.bb b/meta/recipes-devtools/nasm/nasm_2.13.03.bb
index 6a02df4854..730db1d8c2 100644
--- a/meta/recipes-devtools/nasm/nasm_2.13.03.bb
+++ b/meta/recipes-devtools/nasm/nasm_2.13.03.bb
@@ -8,6 +8,7 @@ SRC_URI = "http://www.nasm.us/pub/nasm/releasebuilds/${PV}/nasm-${PV}.tar.bz2 \
            file://0001-assemble-Check-global-line-limit.patch \
            file://0001-fix-CVE-2018-8882.patch \
            file://0001-Verify-that-we-are-not-reading-past-end-of-a-buffer.patch \
+           file://0001-eval-Eliminate-division-by-zero.patch \
            "
 
 SRC_URI[md5sum] = "0c581d482f39d5111879ca9601938f74"