From fe593844957a7ce092ee14e085ee8ddfd6c3b73f Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Fri, 22 May 2015 08:36:40 -0700 Subject: [PATCH] test_bpf: Add backward jump test case Currently the testsuite does not have a test case with a backward jump. The s390x JIT (kernel 4.0) had a bug in that area. So add one new test case for this now. Signed-off-by: Michael Holzheu Signed-off-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- lib/test_bpf.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index aaa0a40a7eb3..9b012a811ee1 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -3940,6 +3940,22 @@ static struct bpf_test tests[] = { { }, { { 0, 1 } }, }, + /* BPF_JMP | BPF_JGT | BPF_K jump backwards */ + { + "JMP_JGT_K: if (3 > 2) return 1 (jump backwards)", + .u.insns_int = { + BPF_JMP_IMM(BPF_JA, 0, 0, 2), /* goto start */ + BPF_ALU32_IMM(BPF_MOV, R0, 1), /* out: */ + BPF_EXIT_INSN(), + BPF_ALU32_IMM(BPF_MOV, R0, 0), /* start: */ + BPF_LD_IMM64(R1, 3), /* note: this takes 2 insns */ + BPF_JMP_IMM(BPF_JGT, R1, 2, -6), /* goto out */ + BPF_EXIT_INSN(), + }, + INTERNAL, + { }, + { { 0, 1 } }, + }, { "JMP_JGE_K: if (3 >= 3) return 1", .u.insns_int = { -- 2.20.1