From 93d41d82963b2cfd0b24c906f5a8daf53281b559 Mon Sep 17 00:00:00 2001
From: "H. Peter Anvin (Intel)" <hpa@zytor.com>
Date: Fri, 16 Aug 2019 01:12:54 -0700
Subject: [PATCH] BR 3392576: don't segfault on a bad %pragma limit

Don't segfault on a bad %pragma limit. Instead treat a NULL pointer as
an empty string.

Reported-by: Ren Kimura <rkx1209dev@gmail.com>
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>

CVE: CVE-2019-14248
Upstream-Status: Backport [https://repo.or.cz/nasm.git/commit/93d41d82963b2cfd0b24c906f5a8daf53281b559]
Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>
---
 asm/nasm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/asm/nasm.c b/asm/nasm.c
index c84d675..65116ab 100644
--- a/asm/nasm.c
+++ b/asm/nasm.c
@@ -212,6 +212,11 @@ nasm_set_limit(const char *limit, const char *valstr)
     bool rn_error;
     int errlevel;
 
+    if (!limit)
+        limit = "";
+    if (!valstr)
+        valstr = "";
+
     for (i = 0; i <= LIMIT_MAX; i++) {
         if (!nasm_stricmp(limit, limit_info[i].name))
             break;
@@ -204,7 +209,7 @@ nasm_set_limit(const char *limit, const char *valstr)
             errlevel = ERR_WARNING|ERR_NOFILE|ERR_USAGE;
         else
             errlevel = ERR_WARNING|ERR_PASS1|WARN_UNKNOWN_PRAGMA;
-        nasm_error(errlevel, "unknown limit: `%s'", limit);
+        nasm_error(errlevel, "invalid limit value: `%s'", valstr);
         return DIRR_ERROR;
     }