diff options
Diffstat (limited to 'arch/arm/net/bpf_jit_32.c')
| -rw-r--r-- | arch/arm/net/bpf_jit_32.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index a34f1e214116..a0bd8a755bdf 100644 --- a/arch/arm/net/bpf_jit_32.c +++ b/arch/arm/net/bpf_jit_32.c @@ -341,10 +341,17 @@ static void emit_load_be16(u8 cond, u8 r_res, u8 r_addr, struct jit_ctx *ctx) static inline void emit_swap16(u8 r_dst, u8 r_src, struct jit_ctx *ctx) { - emit(ARM_LSL_R(ARM_R1, r_src, 8), ctx); - emit(ARM_ORR_S(r_dst, ARM_R1, r_src, SRTYPE_LSL, 8), ctx); - emit(ARM_LSL_I(r_dst, r_dst, 8), ctx); - emit(ARM_LSL_R(r_dst, r_dst, 8), ctx); + /* r_dst = (r_src << 8) | (r_src >> 8) */ + emit(ARM_LSL_I(ARM_R1, r_src, 8), ctx); + emit(ARM_ORR_S(r_dst, ARM_R1, r_src, SRTYPE_LSR, 8), ctx); + + /* + * we need to mask out the bits set in r_dst[23:16] due to + * the first shift instruction. + * + * note that 0x8ff is the encoded immediate 0x00ff0000. + */ + emit(ARM_BIC_I(r_dst, r_dst, 0x8ff), ctx); } #else /* ARMv6+ */ @@ -569,7 +576,7 @@ load_ind: /* x = ((*(frame + k)) & 0xf) << 2; */ ctx->seen |= SEEN_X | SEEN_DATA | SEEN_CALL; /* the interpreter should deal with the negative K */ - if (k < 0) + if ((int)k < 0) return -1; /* offset in r1: we might have to take the slow path */ emit_mov_i(r_off, k, ctx); |