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Subject[PATCH] bpf, arm32: Correct check_imm24
imm24 is signed, so the right range is:
[-(2<<(24 - 1)), (2<<(24 - 1)) - 1]

Note:this patch also fix a typo.

Signed-off-by: Wang YanQing <udknight@gmail.com>
---
arch/arm/net/bpf_jit_32.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index c0b4124..19c6d77 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -84,7 +84,7 @@
*
* 1. First argument is passed using the arm 32bit registers and rest of the
* arguments are passed on stack scratch space.
- * 2. First callee-saved arugument is mapped to arm 32 bit registers and rest
+ * 2. First callee-saved argument is mapped to arm 32 bit registers and rest
* arguments are mapped to scratch space on stack.
* 3. We need two 64 bit temp registers to do complex operations on eBPF
* registers.
@@ -1198,15 +1198,14 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
u8 rd, rt, rm, rn;
s32 jmp_offset;

-#define check_imm(bits, imm) do { \
- if ((((imm) > 0) && ((imm) >> (bits))) || \
- (((imm) < 0) && (~(imm) >> (bits)))) { \
- pr_info("[%2d] imm=%d(0x%x) out of range\n", \
- i, imm, imm); \
+#define check_imm_range(min, max, imm) do { \
+ if (imm < min || imm > max) { \
+ pr_info("[%2d] imm=%d is out of range\n", \
+ i, imm); \
return -EINVAL; \
} \
} while (0)
-#define check_imm24(imm) check_imm(24, imm)
+#define check_imm24(imm) check_imm_range(-16777216, 16777215, imm)

switch (code) {
/* ALU operations */
--
1.8.5.6.2.g3d8a54e.dirty
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