diff options
| -rw-r--r-- | arch/mips/net/bpf_jit.c | 27 | ||||
| -rw-r--r-- | arch/s390/net/bpf_jit_comp.c | 35 | ||||
| -rw-r--r-- | include/linux/skbuff.h | 10 | ||||
| -rw-r--r-- | net/core/filter.c | 31 |
4 files changed, 14 insertions, 89 deletions
diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c index 0e97ccd29fe3..7edc08398c4a 100644 --- a/arch/mips/net/bpf_jit.c +++ b/arch/mips/net/bpf_jit.c @@ -765,27 +765,6 @@ static u64 jit_get_skb_w(struct sk_buff *skb, unsigned offset) return (u64)err << 32 | ntohl(ret); } -#ifdef __BIG_ENDIAN_BITFIELD -#define PKT_TYPE_MAX (7 << 5) -#else -#define PKT_TYPE_MAX 7 -#endif -static int pkt_type_offset(void) -{ - struct sk_buff skb_probe = { - .pkt_type = ~0, - }; - u8 *ct = (u8 *)&skb_probe; - unsigned int off; - - for (off = 0; off < sizeof(struct sk_buff); off++) { - if (ct[off] == PKT_TYPE_MAX) - return off; - } - pr_err_once("Please fix pkt_type_offset(), as pkt_type couldn't be found\n"); - return -1; -} - static int build_body(struct jit_ctx *ctx) { void *load_func[] = {jit_get_skb_b, jit_get_skb_h, jit_get_skb_w}; @@ -1332,11 +1311,7 @@ jmp_cmp: case BPF_ANC | SKF_AD_PKTTYPE: ctx->flags |= SEEN_SKB; - off = pkt_type_offset(); - - if (off < 0) - return -1; - emit_load_byte(r_tmp, r_skb, off, ctx); + emit_load_byte(r_tmp, r_skb, PKT_TYPE_OFFSET(), ctx); /* Keep only the last 3 bits */ emit_andi(r_A, r_tmp, PKT_TYPE_MAX, ctx); #ifdef __BIG_ENDIAN_BITFIELD diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 555f5c7e83ab..c52ac77408ca 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -227,37 +227,6 @@ static void bpf_jit_epilogue(struct bpf_jit *jit) EMIT2(0x07fe); } -/* Helper to find the offset of pkt_type in sk_buff - * Make sure its still a 3bit field starting at the MSBs within a byte. - */ -#define PKT_TYPE_MAX 0xe0 -static int pkt_type_offset; - -static int __init bpf_pkt_type_offset_init(void) -{ - struct sk_buff skb_probe = { - .pkt_type = ~0, - }; - char *ct = (char *)&skb_probe; - int off; - - pkt_type_offset = -1; - for (off = 0; off < sizeof(struct sk_buff); off++) { - if (!ct[off]) - continue; - if (ct[off] == PKT_TYPE_MAX) - pkt_type_offset = off; - else { - /* Found non matching bit pattern, fix needed. */ - WARN_ON_ONCE(1); - pkt_type_offset = -1; - return -1; - } - } - return 0; -} -device_initcall(bpf_pkt_type_offset_init); - /* * make sure we dont leak kernel information to user */ @@ -757,12 +726,10 @@ call_fn: /* lg %r1,<d(function)>(%r13) */ } break; case BPF_ANC | SKF_AD_PKTTYPE: - if (pkt_type_offset < 0) - goto out; /* lhi %r5,0 */ EMIT4(0xa7580000); /* ic %r5,<d(pkt_type_offset)>(%r2) */ - EMIT4_DISP(0x43502000, pkt_type_offset); + EMIT4_DISP(0x43502000, PKT_TYPE_OFFSET()); /* srl %r5,5 */ EMIT4_DISP(0x88500000, 5); break; diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 07c9fdd0c126..756e3d057e84 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -548,6 +548,16 @@ struct sk_buff { ip_summed:2, nohdr:1, nfctinfo:3; + +/* if you move pkt_type around you also must adapt those constants */ +#ifdef __BIG_ENDIAN_BITFIELD +#define PKT_TYPE_MAX (7 << 5) +#else +#define PKT_TYPE_MAX 7 +#endif +#define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) + + __u8 __pkt_type_offset[0]; __u8 pkt_type:3, fclone:2, ipvs_property:1, diff --git a/net/core/filter.c b/net/core/filter.c index dfc716ffa44b..601f28de7311 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -87,30 +87,6 @@ int sk_filter(struct sock *sk, struct sk_buff *skb) } EXPORT_SYMBOL(sk_filter); -/* Helper to find the offset of pkt_type in sk_buff structure. We want - * to make sure its still a 3bit field starting at a byte boundary; - * taken from arch/x86/net/bpf_jit_comp.c. - */ -#ifdef __BIG_ENDIAN_BITFIELD -#define PKT_TYPE_MAX (7 << 5) -#else -#define PKT_TYPE_MAX 7 -#endif -static unsigned int pkt_type_offset(void) -{ - struct sk_buff skb_probe = { .pkt_type = ~0, }; - u8 *ct = (u8 *) &skb_probe; - unsigned int off; - - for (off = 0; off < sizeof(struct sk_buff); off++) { - if (ct[off] == PKT_TYPE_MAX) - return off; - } - - pr_err_once("Please fix %s, as pkt_type couldn't be found!\n", __func__); - return -1; -} - static u64 __skb_get_pay_offset(u64 ctx, u64 a, u64 x, u64 r4, u64 r5) { return skb_get_poff((struct sk_buff *)(unsigned long) ctx); @@ -190,11 +166,8 @@ static bool convert_bpf_extensions(struct sock_filter *fp, break; case SKF_AD_OFF + SKF_AD_PKTTYPE: - *insn = BPF_LDX_MEM(BPF_B, BPF_REG_A, BPF_REG_CTX, - pkt_type_offset()); - if (insn->off < 0) - return false; - insn++; + *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_A, BPF_REG_CTX, + PKT_TYPE_OFFSET()); *insn = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, PKT_TYPE_MAX); #ifdef __BIG_ENDIAN_BITFIELD insn++; |