From 2b589a7e2bd3eb610a4b7f5e61393481755a4de9 Mon Sep 17 00:00:00 2001 From: Wang YanQing Date: Fri, 11 May 2018 11:06:34 +0800 Subject: bpf, arm32: correct check_imm24 imm24 is signed, so the right range is: [-(1<<(24 - 1)), (1<<(24 - 1)) - 1] Note: this patch also fix a typo. Fixes: 39c13c204bb1 ("arm: eBPF JIT compiler") Signed-off-by: Wang YanQing Cc: Shubham Bansal Cc: linux-arm-kernel@lists.infradead.org Cc: linux@armlinux.org.uk Signed-off-by: Daniel Borkmann --- arch/arm/net/bpf_jit_32.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/arm/net/bpf_jit_32.c') diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index d3ea6454e775..0d542007b49d 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. @@ -1192,8 +1192,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) s32 jmp_offset; #define check_imm(bits, imm) do { \ - if ((((imm) > 0) && ((imm) >> (bits))) || \ - (((imm) < 0) && (~(imm) >> (bits)))) { \ + if ((imm) >= (1 << ((bits) - 1)) || \ + (imm) < -(1 << ((bits) - 1))) { \ pr_info("[%2d] imm=%d(0x%x) out of range\n", \ i, imm, imm); \ return -EINVAL; \ -- cgit v1.2.3-59-g8ed1b