From: David Faust <david.faust@oracle.com>
Date: Tue, 7 Dec 2021 19:45:48 +0000 (-0800)
Subject: bpf: avoid potential NULL pointer dereference
X-Git-Tag: basepoints/gcc-13~2470
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e4c2b55b4cefc574a4c2b0b06928220edb9b3f2c;p=thirdparty%2Fgcc.git

bpf: avoid potential NULL pointer dereference

If the result from SSA_NAME_DEF_STMT is NULL, we could try to
dereference it anyway and ICE. Avoid this.

gcc/ChangeLog:

	* config/bpf/bpf.c (handle_attr_preserve): Avoid calling
	is_gimple_assign with a NULL pointer.
---

diff --git a/gcc/config/bpf/bpf.c b/gcc/config/bpf/bpf.c
index 9d2c0bb68188..c054c1ead6b5 100644
--- a/gcc/config/bpf/bpf.c
+++ b/gcc/config/bpf/bpf.c
@@ -1482,7 +1482,7 @@ handle_attr_preserve (function *fn)
 		      && TREE_CODE (TREE_OPERAND (expr, 0)) == SSA_NAME)
 		    {
 		      gimple *def_stmt = SSA_NAME_DEF_STMT (TREE_OPERAND (expr, 0));
-		      if (is_gimple_assign (def_stmt))
+		      if (def_stmt && is_gimple_assign (def_stmt))
 			expr = gimple_assign_rhs1 (def_stmt);
 		    }