From 083b20907185b076f21c265b30fe5b5f24c03d8c Mon Sep 17 00:00:00 2001
From: Mark Lord <mlord@pobox.com>
Date: Tue, 20 Feb 2018 14:49:20 -0500
Subject: [PATCH] powerpc/bpf/jit: Fix 32-bit JIT for seccomp_data access
References: bsc#1065729
Patch-mainline: v4.16-rc3
Git-commit: 083b20907185b076f21c265b30fe5b5f24c03d8c
I am using SECCOMP to filter syscalls on a ppc32 platform, and noticed
that the JIT compiler was failing on the BPF even though the
interpreter was working fine.
The issue was that the compiler was missing one of the instructions
used by SECCOMP, so here is a patch to enable JIT for that
instruction.
Fixes: eb84bab0fb38 ("ppc: Kconfig: Enable BPF JIT on ppc32")
Signed-off-by: Mark Lord <mlord@pobox.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/net/bpf_jit_comp.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 872d1f6dd11e..a9636d8cba15 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -327,6 +327,9 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, len) != 4);
PPC_LWZ_OFFS(r_A, r_skb, offsetof(struct sk_buff, len));
break;
+ case BPF_LDX | BPF_W | BPF_ABS: /* A = *((u32 *)(seccomp_data + K)); */
+ PPC_LWZ_OFFS(r_A, r_skb, K);
+ break;
case BPF_LDX | BPF_W | BPF_LEN: /* X = skb->len; */
PPC_LWZ_OFFS(r_X, r_skb, offsetof(struct sk_buff, len));
break;
--
2.13.6