[src/trunk]: src/tests/lib/libbpfjit Add libbpfjit_jmp_ja_overflow test.

[alnsn <alnsn%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/80827642d1c2
branches:  trunk
changeset: 336093:80827642d1c2
user:      alnsn <alnsn%NetBSD.org@localhost>
date:      Wed Feb 11 23:33:16 2015 +0000

description:
Add libbpfjit_jmp_ja_overflow test.

diffstat:

 tests/lib/libbpfjit/t_bpfjit.c |  30 ++++++++++++++++++++++++++++--
 1 files changed, 28 insertions(+), 2 deletions(-)

diffs (58 lines):

diff -r 23ad70c68e57 -r 80827642d1c2 tests/lib/libbpfjit/t_bpfjit.c
--- a/tests/lib/libbpfjit/t_bpfjit.c    Wed Feb 11 23:29:48 2015 +0000
+++ b/tests/lib/libbpfjit/t_bpfjit.c    Wed Feb 11 23:33:16 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: t_bpfjit.c,v 1.10 2015/02/11 23:17:16 alnsn Exp $ */
+/*     $NetBSD: t_bpfjit.c,v 1.11 2015/02/11 23:33:16 alnsn Exp $ */
 
 /*-
  * Copyright (c) 2011-2012, 2014 Alexander Nasonov.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: t_bpfjit.c,v 1.10 2015/02/11 23:17:16 alnsn Exp $");
+__RCSID("$NetBSD: t_bpfjit.c,v 1.11 2015/02/11 23:33:16 alnsn Exp $");
 
 #include <atf-c.h>
 #include <stdint.h>
@@ -1941,6 +1941,31 @@
        ATF_CHECK(bpfjit_generate_code(NULL, insns, insn_count) == NULL);
 }
 
+ATF_TC(libbpfjit_jmp_ja_overflow);
+ATF_TC_HEAD(libbpfjit_jmp_ja_overflow, tc)
+{
+       atf_tc_set_md_var(tc, "descr",
+           "Test BPF_JMP+BPF_JA with negative offset");
+}
+
+ATF_TC_BODY(libbpfjit_jmp_ja_overflow, tc)
+{
+       static struct bpf_insn insns[] = {
+               BPF_STMT(BPF_JMP+BPF_JA, 1),
+               BPF_STMT(BPF_RET+BPF_K, 777),
+               BPF_STMT(BPF_JMP+BPF_JA, UINT32_MAX - 1), // -2
+               BPF_STMT(BPF_RET+BPF_K, 0)
+       };
+
+       size_t insn_count = sizeof(insns) / sizeof(insns[0]);
+
+       /* Jumps with negative offsets work in userspace ... */
+       ATF_CHECK(bpf_validate(insns, insn_count));
+
+       /* .. but not for bpfjit. */
+       ATF_CHECK(bpfjit_generate_code(NULL, insns, insn_count) == NULL);
+}
+
 ATF_TC(libbpfjit_jmp_jgt_k);
 ATF_TC_HEAD(libbpfjit_jmp_jgt_k, tc)
 {
@@ -4578,6 +4603,7 @@
        ATF_TP_ADD_TC(tp, libbpfjit_alu_neg);
        ATF_TP_ADD_TC(tp, libbpfjit_jmp_ja);
        ATF_TP_ADD_TC(tp, libbpfjit_jmp_ja_invalid);
+       ATF_TP_ADD_TC(tp, libbpfjit_jmp_ja_overflow);
        ATF_TP_ADD_TC(tp, libbpfjit_jmp_jgt_k);
        ATF_TP_ADD_TC(tp, libbpfjit_jmp_jge_k);
        ATF_TP_ADD_TC(tp, libbpfjit_jmp_jeq_k);