From 64b2dd3a8be3ec4e08fd5a3dab0620d9c6c398fe Mon Sep 17 00:00:00 2001
From: David Daney <david.daney@cavium.com>
Date: Tue, 14 Mar 2017 14:21:42 -0700
Subject: [PATCH] MIPS: BPF: Use unsigned access for unsigned SKB fields.
The SKB vlan_tci and queue_mapping fields are unsigned, don't sign
extend these in the BPF JIT. In the vlan_tci case, the value gets
masked so the change is not needed for correctness, but do it anyway
for agreement with the types defined in struct sk_buff.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Steven J. Hill <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15746/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
arch/mips/net/bpf_jit.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c
index 880e329310ee8..a68cd36a892f2 100644
--- a/arch/mips/net/bpf_jit.c
+++ b/arch/mips/net/bpf_jit.c
@@ -1156,7 +1156,7 @@ jmp_cmp:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff,
vlan_tci) != 2);
off = offsetof(struct sk_buff, vlan_tci);
- emit_half_load(r_s0, r_skb, off, ctx);
+ emit_half_load_unsigned(r_s0, r_skb, off, ctx);
if (code == (BPF_ANC | SKF_AD_VLAN_TAG)) {
emit_andi(r_A, r_s0, (u16)~VLAN_TAG_PRESENT, ctx);
} else {
@@ -1183,7 +1183,7 @@ jmp_cmp:
BUILD_BUG_ON(offsetof(struct sk_buff,
queue_mapping) > 0xff);
off = offsetof(struct sk_buff, queue_mapping);
- emit_half_load(r_A, r_skb, off, ctx);
+ emit_half_load_unsigned(r_A, r_skb, off, ctx);
break;
default:
pr_debug("%s: Unhandled opcode: 0x%02x\n", __FILE__,
--
2.30.2