From 48ced849ed621a05cec4c04d4567323af3a76e81 Mon Sep 17 00:00:00 2001 From: dataisland Date: Fri, 15 Sep 2023 18:20:49 +0000 Subject: [PATCH] Fix null-pointer-dereference in yasm_expr_get_intnum Fixes the following CVE: - CVE-2021-33454: NULL pointer dereference in yasm_expr_get_intnum() in libyasm/expr.c For more info see: - https://nvd.nist.gov/vuln/detail/CVE-2021-33454 - https://github.com/yasm/yasm/pull/244 Upstream: https://github.com/yasm/yasm/pull/244 Signed-off-by: Titouan Christophe --- libyasm/expr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libyasm/expr.c b/libyasm/expr.c index c2c868ede..6838eca56 100644 --- a/libyasm/expr.c +++ b/libyasm/expr.c @@ -1260,7 +1260,7 @@ yasm_expr_get_intnum(yasm_expr **ep, int calc_bc_dist) { *ep = yasm_expr_simplify(*ep, calc_bc_dist); - if ((*ep)->op == YASM_EXPR_IDENT && (*ep)->terms[0].type == YASM_EXPR_INT) + if (*ep && (*ep)->op == YASM_EXPR_IDENT && (*ep)->terms[0].type == YASM_EXPR_INT) return (*ep)->terms[0].data.intn; else return (yasm_intnum *)NULL;