From: Ilya Leoshkevich iii@linux.ibm.com
[ Upstream commit bb2d267c448f4bc3a3389d97c56391cb779178ae ]
"masking, test in bounds 3" fails on s390, because BPF_ALU64_IMM(BPF_NEG, BPF_REG_2, 0) ignores the top 32 bits of BPF_REG_2. The reason is that JIT emits lcgfr instead of lcgr. The associated comment indicates that the code was intended to emit lcgr in the first place, it's just that the wrong opcode was used.
Fix by using the correct opcode.
Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Signed-off-by: Ilya Leoshkevich iii@linux.ibm.com Acked-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Signed-off-by: Sasha Levin sashal@kernel.org --- arch/s390/net/bpf_jit_comp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 896344b6e0363..e4616090732a4 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -881,7 +881,7 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i break; case BPF_ALU64 | BPF_NEG: /* dst = -dst */ /* lcgr %dst,%dst */ - EMIT4(0xb9130000, dst_reg, dst_reg); + EMIT4(0xb9030000, dst_reg, dst_reg); break; /* * BPF_FROM_BE/LE