Subject: [PATCH] fix a bug in emitting the 16-bit immediate operand of AND

From: "[email-masked]" <[email-masked]>
Date: Thu, 29 Mar 2012 17:27:00 +0800

When K >= 0xFFFF0000, AND needs the two least significant bytes of K as
its operand, but EMIT2() gives it the least significant byte of K and
0x2. EMIT() should be used here to replace EMIT2().

Signed-off-by: Feiran Zhuang  <[email-masked]>
---
 arch/x86/net/bpf_jit_comp.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 5671752..5a5b6e4 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -289,7 +289,7 @@ void bpf_jit_compile(struct sk_filter *fp)
 					EMIT2(0x24, K & 0xFF); /* and imm8,%al */
 				} else if (K >= 0xFFFF0000) {
 					EMIT2(0x66, 0x25);	/* and imm16,%ax */
-					EMIT2(K, 2);
+					EMIT(K, 2);
 				} else {
 					EMIT1_off32(0x25, K);	/* and imm32,%eax */
 				}
-- 
1.7.5.4