mirror of https://gitee.com/openkylin/linux.git
1174 lines
31 KiB
C
1174 lines
31 KiB
C
/*
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* Linux Socket Filter - Kernel level socket filtering
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*
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* Based on the design of the Berkeley Packet Filter. The new
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* internal format has been designed by PLUMgrid:
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*
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* Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
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*
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* Authors:
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*
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* Jay Schulist <jschlst@samba.org>
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* Alexei Starovoitov <ast@plumgrid.com>
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* Daniel Borkmann <dborkman@redhat.com>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Andi Kleen - Fix a few bad bugs and races.
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* Kris Katterjohn - Added many additional checks in bpf_check_classic()
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*/
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#include <linux/filter.h>
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#include <linux/skbuff.h>
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#include <linux/vmalloc.h>
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#include <linux/random.h>
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#include <linux/moduleloader.h>
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#include <linux/bpf.h>
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#include <linux/frame.h>
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#include <asm/unaligned.h>
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/* Registers */
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#define BPF_R0 regs[BPF_REG_0]
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#define BPF_R1 regs[BPF_REG_1]
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#define BPF_R2 regs[BPF_REG_2]
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#define BPF_R3 regs[BPF_REG_3]
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#define BPF_R4 regs[BPF_REG_4]
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#define BPF_R5 regs[BPF_REG_5]
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#define BPF_R6 regs[BPF_REG_6]
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#define BPF_R7 regs[BPF_REG_7]
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#define BPF_R8 regs[BPF_REG_8]
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#define BPF_R9 regs[BPF_REG_9]
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#define BPF_R10 regs[BPF_REG_10]
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/* Named registers */
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#define DST regs[insn->dst_reg]
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#define SRC regs[insn->src_reg]
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#define FP regs[BPF_REG_FP]
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#define ARG1 regs[BPF_REG_ARG1]
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#define CTX regs[BPF_REG_CTX]
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#define IMM insn->imm
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/* No hurry in this branch
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*
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* Exported for the bpf jit load helper.
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*/
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void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size)
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{
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u8 *ptr = NULL;
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if (k >= SKF_NET_OFF)
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ptr = skb_network_header(skb) + k - SKF_NET_OFF;
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else if (k >= SKF_LL_OFF)
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ptr = skb_mac_header(skb) + k - SKF_LL_OFF;
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if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb))
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return ptr;
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return NULL;
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}
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struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
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{
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gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
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gfp_extra_flags;
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struct bpf_prog_aux *aux;
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struct bpf_prog *fp;
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size = round_up(size, PAGE_SIZE);
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fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
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if (fp == NULL)
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return NULL;
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kmemcheck_annotate_bitfield(fp, meta);
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aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
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if (aux == NULL) {
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vfree(fp);
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return NULL;
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}
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fp->pages = size / PAGE_SIZE;
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fp->aux = aux;
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fp->aux->prog = fp;
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return fp;
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}
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EXPORT_SYMBOL_GPL(bpf_prog_alloc);
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struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
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gfp_t gfp_extra_flags)
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{
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gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
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gfp_extra_flags;
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struct bpf_prog *fp;
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u32 pages, delta;
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int ret;
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BUG_ON(fp_old == NULL);
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size = round_up(size, PAGE_SIZE);
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pages = size / PAGE_SIZE;
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if (pages <= fp_old->pages)
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return fp_old;
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delta = pages - fp_old->pages;
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ret = __bpf_prog_charge(fp_old->aux->user, delta);
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if (ret)
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return NULL;
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fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
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if (fp == NULL) {
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__bpf_prog_uncharge(fp_old->aux->user, delta);
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} else {
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kmemcheck_annotate_bitfield(fp, meta);
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memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
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fp->pages = pages;
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fp->aux->prog = fp;
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/* We keep fp->aux from fp_old around in the new
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* reallocated structure.
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*/
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fp_old->aux = NULL;
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__bpf_prog_free(fp_old);
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}
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return fp;
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}
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void __bpf_prog_free(struct bpf_prog *fp)
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{
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kfree(fp->aux);
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vfree(fp);
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}
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int bpf_prog_calc_digest(struct bpf_prog *fp)
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{
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const u32 bits_offset = SHA_MESSAGE_BYTES - sizeof(__be64);
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u32 raw_size = bpf_prog_digest_scratch_size(fp);
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u32 ws[SHA_WORKSPACE_WORDS];
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u32 i, bsize, psize, blocks;
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struct bpf_insn *dst;
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bool was_ld_map;
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u8 *raw, *todo;
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__be32 *result;
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__be64 *bits;
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raw = vmalloc(raw_size);
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if (!raw)
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return -ENOMEM;
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sha_init(fp->digest);
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memset(ws, 0, sizeof(ws));
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/* We need to take out the map fd for the digest calculation
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* since they are unstable from user space side.
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*/
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dst = (void *)raw;
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for (i = 0, was_ld_map = false; i < fp->len; i++) {
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dst[i] = fp->insnsi[i];
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if (!was_ld_map &&
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dst[i].code == (BPF_LD | BPF_IMM | BPF_DW) &&
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dst[i].src_reg == BPF_PSEUDO_MAP_FD) {
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was_ld_map = true;
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dst[i].imm = 0;
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} else if (was_ld_map &&
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dst[i].code == 0 &&
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dst[i].dst_reg == 0 &&
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dst[i].src_reg == 0 &&
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dst[i].off == 0) {
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was_ld_map = false;
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dst[i].imm = 0;
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} else {
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was_ld_map = false;
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}
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}
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psize = bpf_prog_insn_size(fp);
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memset(&raw[psize], 0, raw_size - psize);
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raw[psize++] = 0x80;
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bsize = round_up(psize, SHA_MESSAGE_BYTES);
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blocks = bsize / SHA_MESSAGE_BYTES;
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todo = raw;
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if (bsize - psize >= sizeof(__be64)) {
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bits = (__be64 *)(todo + bsize - sizeof(__be64));
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} else {
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bits = (__be64 *)(todo + bsize + bits_offset);
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blocks++;
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}
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*bits = cpu_to_be64((psize - 1) << 3);
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while (blocks--) {
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sha_transform(fp->digest, todo, ws);
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todo += SHA_MESSAGE_BYTES;
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}
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result = (__force __be32 *)fp->digest;
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for (i = 0; i < SHA_DIGEST_WORDS; i++)
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result[i] = cpu_to_be32(fp->digest[i]);
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vfree(raw);
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return 0;
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}
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static bool bpf_is_jmp_and_has_target(const struct bpf_insn *insn)
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{
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return BPF_CLASS(insn->code) == BPF_JMP &&
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/* Call and Exit are both special jumps with no
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* target inside the BPF instruction image.
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*/
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BPF_OP(insn->code) != BPF_CALL &&
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BPF_OP(insn->code) != BPF_EXIT;
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}
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static void bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta)
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{
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struct bpf_insn *insn = prog->insnsi;
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u32 i, insn_cnt = prog->len;
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for (i = 0; i < insn_cnt; i++, insn++) {
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if (!bpf_is_jmp_and_has_target(insn))
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continue;
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/* Adjust offset of jmps if we cross boundaries. */
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if (i < pos && i + insn->off + 1 > pos)
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insn->off += delta;
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else if (i > pos + delta && i + insn->off + 1 <= pos + delta)
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insn->off -= delta;
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}
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}
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struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
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const struct bpf_insn *patch, u32 len)
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{
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u32 insn_adj_cnt, insn_rest, insn_delta = len - 1;
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struct bpf_prog *prog_adj;
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/* Since our patchlet doesn't expand the image, we're done. */
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if (insn_delta == 0) {
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memcpy(prog->insnsi + off, patch, sizeof(*patch));
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return prog;
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}
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insn_adj_cnt = prog->len + insn_delta;
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/* Several new instructions need to be inserted. Make room
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* for them. Likely, there's no need for a new allocation as
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* last page could have large enough tailroom.
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*/
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prog_adj = bpf_prog_realloc(prog, bpf_prog_size(insn_adj_cnt),
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GFP_USER);
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if (!prog_adj)
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return NULL;
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prog_adj->len = insn_adj_cnt;
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/* Patching happens in 3 steps:
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*
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* 1) Move over tail of insnsi from next instruction onwards,
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* so we can patch the single target insn with one or more
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* new ones (patching is always from 1 to n insns, n > 0).
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* 2) Inject new instructions at the target location.
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* 3) Adjust branch offsets if necessary.
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*/
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insn_rest = insn_adj_cnt - off - len;
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memmove(prog_adj->insnsi + off + len, prog_adj->insnsi + off + 1,
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sizeof(*patch) * insn_rest);
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memcpy(prog_adj->insnsi + off, patch, sizeof(*patch) * len);
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bpf_adj_branches(prog_adj, off, insn_delta);
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return prog_adj;
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}
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#ifdef CONFIG_BPF_JIT
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struct bpf_binary_header *
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bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
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unsigned int alignment,
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bpf_jit_fill_hole_t bpf_fill_ill_insns)
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{
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struct bpf_binary_header *hdr;
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unsigned int size, hole, start;
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/* Most of BPF filters are really small, but if some of them
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* fill a page, allow at least 128 extra bytes to insert a
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* random section of illegal instructions.
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*/
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size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
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hdr = module_alloc(size);
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if (hdr == NULL)
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return NULL;
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/* Fill space with illegal/arch-dep instructions. */
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bpf_fill_ill_insns(hdr, size);
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hdr->pages = size / PAGE_SIZE;
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hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)),
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PAGE_SIZE - sizeof(*hdr));
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start = (get_random_int() % hole) & ~(alignment - 1);
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/* Leave a random number of instructions before BPF code. */
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*image_ptr = &hdr->image[start];
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return hdr;
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}
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void bpf_jit_binary_free(struct bpf_binary_header *hdr)
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{
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module_memfree(hdr);
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}
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int bpf_jit_harden __read_mostly;
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static int bpf_jit_blind_insn(const struct bpf_insn *from,
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const struct bpf_insn *aux,
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struct bpf_insn *to_buff)
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{
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struct bpf_insn *to = to_buff;
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u32 imm_rnd = get_random_int();
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s16 off;
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BUILD_BUG_ON(BPF_REG_AX + 1 != MAX_BPF_JIT_REG);
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BUILD_BUG_ON(MAX_BPF_REG + 1 != MAX_BPF_JIT_REG);
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if (from->imm == 0 &&
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(from->code == (BPF_ALU | BPF_MOV | BPF_K) ||
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from->code == (BPF_ALU64 | BPF_MOV | BPF_K))) {
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*to++ = BPF_ALU64_REG(BPF_XOR, from->dst_reg, from->dst_reg);
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goto out;
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}
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switch (from->code) {
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case BPF_ALU | BPF_ADD | BPF_K:
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case BPF_ALU | BPF_SUB | BPF_K:
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case BPF_ALU | BPF_AND | BPF_K:
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case BPF_ALU | BPF_OR | BPF_K:
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case BPF_ALU | BPF_XOR | BPF_K:
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case BPF_ALU | BPF_MUL | BPF_K:
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case BPF_ALU | BPF_MOV | BPF_K:
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case BPF_ALU | BPF_DIV | BPF_K:
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case BPF_ALU | BPF_MOD | BPF_K:
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*to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
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*to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_ALU32_REG(from->code, from->dst_reg, BPF_REG_AX);
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break;
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case BPF_ALU64 | BPF_ADD | BPF_K:
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case BPF_ALU64 | BPF_SUB | BPF_K:
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case BPF_ALU64 | BPF_AND | BPF_K:
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case BPF_ALU64 | BPF_OR | BPF_K:
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case BPF_ALU64 | BPF_XOR | BPF_K:
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case BPF_ALU64 | BPF_MUL | BPF_K:
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case BPF_ALU64 | BPF_MOV | BPF_K:
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case BPF_ALU64 | BPF_DIV | BPF_K:
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case BPF_ALU64 | BPF_MOD | BPF_K:
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*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
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*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_ALU64_REG(from->code, from->dst_reg, BPF_REG_AX);
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break;
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case BPF_JMP | BPF_JEQ | BPF_K:
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case BPF_JMP | BPF_JNE | BPF_K:
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case BPF_JMP | BPF_JGT | BPF_K:
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case BPF_JMP | BPF_JGE | BPF_K:
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case BPF_JMP | BPF_JSGT | BPF_K:
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case BPF_JMP | BPF_JSGE | BPF_K:
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case BPF_JMP | BPF_JSET | BPF_K:
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/* Accommodate for extra offset in case of a backjump. */
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off = from->off;
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if (off < 0)
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off -= 2;
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*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
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*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off);
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break;
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case BPF_LD | BPF_ABS | BPF_W:
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case BPF_LD | BPF_ABS | BPF_H:
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case BPF_LD | BPF_ABS | BPF_B:
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*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
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*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0);
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break;
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|
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case BPF_LD | BPF_IND | BPF_W:
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case BPF_LD | BPF_IND | BPF_H:
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case BPF_LD | BPF_IND | BPF_B:
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*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
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*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_ALU32_REG(BPF_ADD, BPF_REG_AX, from->src_reg);
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*to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0);
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break;
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|
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case BPF_LD | BPF_IMM | BPF_DW:
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*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm);
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*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_ALU64_IMM(BPF_LSH, BPF_REG_AX, 32);
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*to++ = BPF_ALU64_REG(BPF_MOV, aux[0].dst_reg, BPF_REG_AX);
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break;
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case 0: /* Part 2 of BPF_LD | BPF_IMM | BPF_DW. */
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*to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[0].imm);
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*to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_ALU64_REG(BPF_OR, aux[0].dst_reg, BPF_REG_AX);
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break;
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case BPF_ST | BPF_MEM | BPF_DW:
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case BPF_ST | BPF_MEM | BPF_W:
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case BPF_ST | BPF_MEM | BPF_H:
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case BPF_ST | BPF_MEM | BPF_B:
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*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
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*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
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*to++ = BPF_STX_MEM(from->code, from->dst_reg, BPF_REG_AX, from->off);
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break;
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}
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out:
|
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return to - to_buff;
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}
|
|
|
|
static struct bpf_prog *bpf_prog_clone_create(struct bpf_prog *fp_other,
|
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gfp_t gfp_extra_flags)
|
|
{
|
|
gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
|
|
gfp_extra_flags;
|
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struct bpf_prog *fp;
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|
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fp = __vmalloc(fp_other->pages * PAGE_SIZE, gfp_flags, PAGE_KERNEL);
|
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if (fp != NULL) {
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kmemcheck_annotate_bitfield(fp, meta);
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|
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/* aux->prog still points to the fp_other one, so
|
|
* when promoting the clone to the real program,
|
|
* this still needs to be adapted.
|
|
*/
|
|
memcpy(fp, fp_other, fp_other->pages * PAGE_SIZE);
|
|
}
|
|
|
|
return fp;
|
|
}
|
|
|
|
static void bpf_prog_clone_free(struct bpf_prog *fp)
|
|
{
|
|
/* aux was stolen by the other clone, so we cannot free
|
|
* it from this path! It will be freed eventually by the
|
|
* other program on release.
|
|
*
|
|
* At this point, we don't need a deferred release since
|
|
* clone is guaranteed to not be locked.
|
|
*/
|
|
fp->aux = NULL;
|
|
__bpf_prog_free(fp);
|
|
}
|
|
|
|
void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other)
|
|
{
|
|
/* We have to repoint aux->prog to self, as we don't
|
|
* know whether fp here is the clone or the original.
|
|
*/
|
|
fp->aux->prog = fp;
|
|
bpf_prog_clone_free(fp_other);
|
|
}
|
|
|
|
struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
|
|
{
|
|
struct bpf_insn insn_buff[16], aux[2];
|
|
struct bpf_prog *clone, *tmp;
|
|
int insn_delta, insn_cnt;
|
|
struct bpf_insn *insn;
|
|
int i, rewritten;
|
|
|
|
if (!bpf_jit_blinding_enabled())
|
|
return prog;
|
|
|
|
clone = bpf_prog_clone_create(prog, GFP_USER);
|
|
if (!clone)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
insn_cnt = clone->len;
|
|
insn = clone->insnsi;
|
|
|
|
for (i = 0; i < insn_cnt; i++, insn++) {
|
|
/* We temporarily need to hold the original ld64 insn
|
|
* so that we can still access the first part in the
|
|
* second blinding run.
|
|
*/
|
|
if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW) &&
|
|
insn[1].code == 0)
|
|
memcpy(aux, insn, sizeof(aux));
|
|
|
|
rewritten = bpf_jit_blind_insn(insn, aux, insn_buff);
|
|
if (!rewritten)
|
|
continue;
|
|
|
|
tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
|
|
if (!tmp) {
|
|
/* Patching may have repointed aux->prog during
|
|
* realloc from the original one, so we need to
|
|
* fix it up here on error.
|
|
*/
|
|
bpf_jit_prog_release_other(prog, clone);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
clone = tmp;
|
|
insn_delta = rewritten - 1;
|
|
|
|
/* Walk new program and skip insns we just inserted. */
|
|
insn = clone->insnsi + i + insn_delta;
|
|
insn_cnt += insn_delta;
|
|
i += insn_delta;
|
|
}
|
|
|
|
return clone;
|
|
}
|
|
#endif /* CONFIG_BPF_JIT */
|
|
|
|
/* Base function for offset calculation. Needs to go into .text section,
|
|
* therefore keeping it non-static as well; will also be used by JITs
|
|
* anyway later on, so do not let the compiler omit it.
|
|
*/
|
|
noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
|
|
{
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__bpf_call_base);
|
|
|
|
/**
|
|
* __bpf_prog_run - run eBPF program on a given context
|
|
* @ctx: is the data we are operating on
|
|
* @insn: is the array of eBPF instructions
|
|
*
|
|
* Decode and execute eBPF instructions.
|
|
*/
|
|
static unsigned int __bpf_prog_run(void *ctx, const struct bpf_insn *insn)
|
|
{
|
|
u64 stack[MAX_BPF_STACK / sizeof(u64)];
|
|
u64 regs[MAX_BPF_REG], tmp;
|
|
static const void *jumptable[256] = {
|
|
[0 ... 255] = &&default_label,
|
|
/* Now overwrite non-defaults ... */
|
|
/* 32 bit ALU operations */
|
|
[BPF_ALU | BPF_ADD | BPF_X] = &&ALU_ADD_X,
|
|
[BPF_ALU | BPF_ADD | BPF_K] = &&ALU_ADD_K,
|
|
[BPF_ALU | BPF_SUB | BPF_X] = &&ALU_SUB_X,
|
|
[BPF_ALU | BPF_SUB | BPF_K] = &&ALU_SUB_K,
|
|
[BPF_ALU | BPF_AND | BPF_X] = &&ALU_AND_X,
|
|
[BPF_ALU | BPF_AND | BPF_K] = &&ALU_AND_K,
|
|
[BPF_ALU | BPF_OR | BPF_X] = &&ALU_OR_X,
|
|
[BPF_ALU | BPF_OR | BPF_K] = &&ALU_OR_K,
|
|
[BPF_ALU | BPF_LSH | BPF_X] = &&ALU_LSH_X,
|
|
[BPF_ALU | BPF_LSH | BPF_K] = &&ALU_LSH_K,
|
|
[BPF_ALU | BPF_RSH | BPF_X] = &&ALU_RSH_X,
|
|
[BPF_ALU | BPF_RSH | BPF_K] = &&ALU_RSH_K,
|
|
[BPF_ALU | BPF_XOR | BPF_X] = &&ALU_XOR_X,
|
|
[BPF_ALU | BPF_XOR | BPF_K] = &&ALU_XOR_K,
|
|
[BPF_ALU | BPF_MUL | BPF_X] = &&ALU_MUL_X,
|
|
[BPF_ALU | BPF_MUL | BPF_K] = &&ALU_MUL_K,
|
|
[BPF_ALU | BPF_MOV | BPF_X] = &&ALU_MOV_X,
|
|
[BPF_ALU | BPF_MOV | BPF_K] = &&ALU_MOV_K,
|
|
[BPF_ALU | BPF_DIV | BPF_X] = &&ALU_DIV_X,
|
|
[BPF_ALU | BPF_DIV | BPF_K] = &&ALU_DIV_K,
|
|
[BPF_ALU | BPF_MOD | BPF_X] = &&ALU_MOD_X,
|
|
[BPF_ALU | BPF_MOD | BPF_K] = &&ALU_MOD_K,
|
|
[BPF_ALU | BPF_NEG] = &&ALU_NEG,
|
|
[BPF_ALU | BPF_END | BPF_TO_BE] = &&ALU_END_TO_BE,
|
|
[BPF_ALU | BPF_END | BPF_TO_LE] = &&ALU_END_TO_LE,
|
|
/* 64 bit ALU operations */
|
|
[BPF_ALU64 | BPF_ADD | BPF_X] = &&ALU64_ADD_X,
|
|
[BPF_ALU64 | BPF_ADD | BPF_K] = &&ALU64_ADD_K,
|
|
[BPF_ALU64 | BPF_SUB | BPF_X] = &&ALU64_SUB_X,
|
|
[BPF_ALU64 | BPF_SUB | BPF_K] = &&ALU64_SUB_K,
|
|
[BPF_ALU64 | BPF_AND | BPF_X] = &&ALU64_AND_X,
|
|
[BPF_ALU64 | BPF_AND | BPF_K] = &&ALU64_AND_K,
|
|
[BPF_ALU64 | BPF_OR | BPF_X] = &&ALU64_OR_X,
|
|
[BPF_ALU64 | BPF_OR | BPF_K] = &&ALU64_OR_K,
|
|
[BPF_ALU64 | BPF_LSH | BPF_X] = &&ALU64_LSH_X,
|
|
[BPF_ALU64 | BPF_LSH | BPF_K] = &&ALU64_LSH_K,
|
|
[BPF_ALU64 | BPF_RSH | BPF_X] = &&ALU64_RSH_X,
|
|
[BPF_ALU64 | BPF_RSH | BPF_K] = &&ALU64_RSH_K,
|
|
[BPF_ALU64 | BPF_XOR | BPF_X] = &&ALU64_XOR_X,
|
|
[BPF_ALU64 | BPF_XOR | BPF_K] = &&ALU64_XOR_K,
|
|
[BPF_ALU64 | BPF_MUL | BPF_X] = &&ALU64_MUL_X,
|
|
[BPF_ALU64 | BPF_MUL | BPF_K] = &&ALU64_MUL_K,
|
|
[BPF_ALU64 | BPF_MOV | BPF_X] = &&ALU64_MOV_X,
|
|
[BPF_ALU64 | BPF_MOV | BPF_K] = &&ALU64_MOV_K,
|
|
[BPF_ALU64 | BPF_ARSH | BPF_X] = &&ALU64_ARSH_X,
|
|
[BPF_ALU64 | BPF_ARSH | BPF_K] = &&ALU64_ARSH_K,
|
|
[BPF_ALU64 | BPF_DIV | BPF_X] = &&ALU64_DIV_X,
|
|
[BPF_ALU64 | BPF_DIV | BPF_K] = &&ALU64_DIV_K,
|
|
[BPF_ALU64 | BPF_MOD | BPF_X] = &&ALU64_MOD_X,
|
|
[BPF_ALU64 | BPF_MOD | BPF_K] = &&ALU64_MOD_K,
|
|
[BPF_ALU64 | BPF_NEG] = &&ALU64_NEG,
|
|
/* Call instruction */
|
|
[BPF_JMP | BPF_CALL] = &&JMP_CALL,
|
|
[BPF_JMP | BPF_CALL | BPF_X] = &&JMP_TAIL_CALL,
|
|
/* Jumps */
|
|
[BPF_JMP | BPF_JA] = &&JMP_JA,
|
|
[BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X,
|
|
[BPF_JMP | BPF_JEQ | BPF_K] = &&JMP_JEQ_K,
|
|
[BPF_JMP | BPF_JNE | BPF_X] = &&JMP_JNE_X,
|
|
[BPF_JMP | BPF_JNE | BPF_K] = &&JMP_JNE_K,
|
|
[BPF_JMP | BPF_JGT | BPF_X] = &&JMP_JGT_X,
|
|
[BPF_JMP | BPF_JGT | BPF_K] = &&JMP_JGT_K,
|
|
[BPF_JMP | BPF_JGE | BPF_X] = &&JMP_JGE_X,
|
|
[BPF_JMP | BPF_JGE | BPF_K] = &&JMP_JGE_K,
|
|
[BPF_JMP | BPF_JSGT | BPF_X] = &&JMP_JSGT_X,
|
|
[BPF_JMP | BPF_JSGT | BPF_K] = &&JMP_JSGT_K,
|
|
[BPF_JMP | BPF_JSGE | BPF_X] = &&JMP_JSGE_X,
|
|
[BPF_JMP | BPF_JSGE | BPF_K] = &&JMP_JSGE_K,
|
|
[BPF_JMP | BPF_JSET | BPF_X] = &&JMP_JSET_X,
|
|
[BPF_JMP | BPF_JSET | BPF_K] = &&JMP_JSET_K,
|
|
/* Program return */
|
|
[BPF_JMP | BPF_EXIT] = &&JMP_EXIT,
|
|
/* Store instructions */
|
|
[BPF_STX | BPF_MEM | BPF_B] = &&STX_MEM_B,
|
|
[BPF_STX | BPF_MEM | BPF_H] = &&STX_MEM_H,
|
|
[BPF_STX | BPF_MEM | BPF_W] = &&STX_MEM_W,
|
|
[BPF_STX | BPF_MEM | BPF_DW] = &&STX_MEM_DW,
|
|
[BPF_STX | BPF_XADD | BPF_W] = &&STX_XADD_W,
|
|
[BPF_STX | BPF_XADD | BPF_DW] = &&STX_XADD_DW,
|
|
[BPF_ST | BPF_MEM | BPF_B] = &&ST_MEM_B,
|
|
[BPF_ST | BPF_MEM | BPF_H] = &&ST_MEM_H,
|
|
[BPF_ST | BPF_MEM | BPF_W] = &&ST_MEM_W,
|
|
[BPF_ST | BPF_MEM | BPF_DW] = &&ST_MEM_DW,
|
|
/* Load instructions */
|
|
[BPF_LDX | BPF_MEM | BPF_B] = &&LDX_MEM_B,
|
|
[BPF_LDX | BPF_MEM | BPF_H] = &&LDX_MEM_H,
|
|
[BPF_LDX | BPF_MEM | BPF_W] = &&LDX_MEM_W,
|
|
[BPF_LDX | BPF_MEM | BPF_DW] = &&LDX_MEM_DW,
|
|
[BPF_LD | BPF_ABS | BPF_W] = &&LD_ABS_W,
|
|
[BPF_LD | BPF_ABS | BPF_H] = &&LD_ABS_H,
|
|
[BPF_LD | BPF_ABS | BPF_B] = &&LD_ABS_B,
|
|
[BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W,
|
|
[BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H,
|
|
[BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B,
|
|
[BPF_LD | BPF_IMM | BPF_DW] = &&LD_IMM_DW,
|
|
};
|
|
u32 tail_call_cnt = 0;
|
|
void *ptr;
|
|
int off;
|
|
|
|
#define CONT ({ insn++; goto select_insn; })
|
|
#define CONT_JMP ({ insn++; goto select_insn; })
|
|
|
|
FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)];
|
|
ARG1 = (u64) (unsigned long) ctx;
|
|
|
|
select_insn:
|
|
goto *jumptable[insn->code];
|
|
|
|
/* ALU */
|
|
#define ALU(OPCODE, OP) \
|
|
ALU64_##OPCODE##_X: \
|
|
DST = DST OP SRC; \
|
|
CONT; \
|
|
ALU_##OPCODE##_X: \
|
|
DST = (u32) DST OP (u32) SRC; \
|
|
CONT; \
|
|
ALU64_##OPCODE##_K: \
|
|
DST = DST OP IMM; \
|
|
CONT; \
|
|
ALU_##OPCODE##_K: \
|
|
DST = (u32) DST OP (u32) IMM; \
|
|
CONT;
|
|
|
|
ALU(ADD, +)
|
|
ALU(SUB, -)
|
|
ALU(AND, &)
|
|
ALU(OR, |)
|
|
ALU(LSH, <<)
|
|
ALU(RSH, >>)
|
|
ALU(XOR, ^)
|
|
ALU(MUL, *)
|
|
#undef ALU
|
|
ALU_NEG:
|
|
DST = (u32) -DST;
|
|
CONT;
|
|
ALU64_NEG:
|
|
DST = -DST;
|
|
CONT;
|
|
ALU_MOV_X:
|
|
DST = (u32) SRC;
|
|
CONT;
|
|
ALU_MOV_K:
|
|
DST = (u32) IMM;
|
|
CONT;
|
|
ALU64_MOV_X:
|
|
DST = SRC;
|
|
CONT;
|
|
ALU64_MOV_K:
|
|
DST = IMM;
|
|
CONT;
|
|
LD_IMM_DW:
|
|
DST = (u64) (u32) insn[0].imm | ((u64) (u32) insn[1].imm) << 32;
|
|
insn++;
|
|
CONT;
|
|
ALU64_ARSH_X:
|
|
(*(s64 *) &DST) >>= SRC;
|
|
CONT;
|
|
ALU64_ARSH_K:
|
|
(*(s64 *) &DST) >>= IMM;
|
|
CONT;
|
|
ALU64_MOD_X:
|
|
if (unlikely(SRC == 0))
|
|
return 0;
|
|
div64_u64_rem(DST, SRC, &tmp);
|
|
DST = tmp;
|
|
CONT;
|
|
ALU_MOD_X:
|
|
if (unlikely(SRC == 0))
|
|
return 0;
|
|
tmp = (u32) DST;
|
|
DST = do_div(tmp, (u32) SRC);
|
|
CONT;
|
|
ALU64_MOD_K:
|
|
div64_u64_rem(DST, IMM, &tmp);
|
|
DST = tmp;
|
|
CONT;
|
|
ALU_MOD_K:
|
|
tmp = (u32) DST;
|
|
DST = do_div(tmp, (u32) IMM);
|
|
CONT;
|
|
ALU64_DIV_X:
|
|
if (unlikely(SRC == 0))
|
|
return 0;
|
|
DST = div64_u64(DST, SRC);
|
|
CONT;
|
|
ALU_DIV_X:
|
|
if (unlikely(SRC == 0))
|
|
return 0;
|
|
tmp = (u32) DST;
|
|
do_div(tmp, (u32) SRC);
|
|
DST = (u32) tmp;
|
|
CONT;
|
|
ALU64_DIV_K:
|
|
DST = div64_u64(DST, IMM);
|
|
CONT;
|
|
ALU_DIV_K:
|
|
tmp = (u32) DST;
|
|
do_div(tmp, (u32) IMM);
|
|
DST = (u32) tmp;
|
|
CONT;
|
|
ALU_END_TO_BE:
|
|
switch (IMM) {
|
|
case 16:
|
|
DST = (__force u16) cpu_to_be16(DST);
|
|
break;
|
|
case 32:
|
|
DST = (__force u32) cpu_to_be32(DST);
|
|
break;
|
|
case 64:
|
|
DST = (__force u64) cpu_to_be64(DST);
|
|
break;
|
|
}
|
|
CONT;
|
|
ALU_END_TO_LE:
|
|
switch (IMM) {
|
|
case 16:
|
|
DST = (__force u16) cpu_to_le16(DST);
|
|
break;
|
|
case 32:
|
|
DST = (__force u32) cpu_to_le32(DST);
|
|
break;
|
|
case 64:
|
|
DST = (__force u64) cpu_to_le64(DST);
|
|
break;
|
|
}
|
|
CONT;
|
|
|
|
/* CALL */
|
|
JMP_CALL:
|
|
/* Function call scratches BPF_R1-BPF_R5 registers,
|
|
* preserves BPF_R6-BPF_R9, and stores return value
|
|
* into BPF_R0.
|
|
*/
|
|
BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3,
|
|
BPF_R4, BPF_R5);
|
|
CONT;
|
|
|
|
JMP_TAIL_CALL: {
|
|
struct bpf_map *map = (struct bpf_map *) (unsigned long) BPF_R2;
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
struct bpf_prog *prog;
|
|
u64 index = BPF_R3;
|
|
|
|
if (unlikely(index >= array->map.max_entries))
|
|
goto out;
|
|
if (unlikely(tail_call_cnt > MAX_TAIL_CALL_CNT))
|
|
goto out;
|
|
|
|
tail_call_cnt++;
|
|
|
|
prog = READ_ONCE(array->ptrs[index]);
|
|
if (!prog)
|
|
goto out;
|
|
|
|
/* ARG1 at this point is guaranteed to point to CTX from
|
|
* the verifier side due to the fact that the tail call is
|
|
* handeled like a helper, that is, bpf_tail_call_proto,
|
|
* where arg1_type is ARG_PTR_TO_CTX.
|
|
*/
|
|
insn = prog->insnsi;
|
|
goto select_insn;
|
|
out:
|
|
CONT;
|
|
}
|
|
/* JMP */
|
|
JMP_JA:
|
|
insn += insn->off;
|
|
CONT;
|
|
JMP_JEQ_X:
|
|
if (DST == SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JEQ_K:
|
|
if (DST == IMM) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JNE_X:
|
|
if (DST != SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JNE_K:
|
|
if (DST != IMM) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JGT_X:
|
|
if (DST > SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JGT_K:
|
|
if (DST > IMM) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JGE_X:
|
|
if (DST >= SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JGE_K:
|
|
if (DST >= IMM) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSGT_X:
|
|
if (((s64) DST) > ((s64) SRC)) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSGT_K:
|
|
if (((s64) DST) > ((s64) IMM)) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSGE_X:
|
|
if (((s64) DST) >= ((s64) SRC)) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSGE_K:
|
|
if (((s64) DST) >= ((s64) IMM)) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSET_X:
|
|
if (DST & SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSET_K:
|
|
if (DST & IMM) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_EXIT:
|
|
return BPF_R0;
|
|
|
|
/* STX and ST and LDX*/
|
|
#define LDST(SIZEOP, SIZE) \
|
|
STX_MEM_##SIZEOP: \
|
|
*(SIZE *)(unsigned long) (DST + insn->off) = SRC; \
|
|
CONT; \
|
|
ST_MEM_##SIZEOP: \
|
|
*(SIZE *)(unsigned long) (DST + insn->off) = IMM; \
|
|
CONT; \
|
|
LDX_MEM_##SIZEOP: \
|
|
DST = *(SIZE *)(unsigned long) (SRC + insn->off); \
|
|
CONT;
|
|
|
|
LDST(B, u8)
|
|
LDST(H, u16)
|
|
LDST(W, u32)
|
|
LDST(DW, u64)
|
|
#undef LDST
|
|
STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
|
|
atomic_add((u32) SRC, (atomic_t *)(unsigned long)
|
|
(DST + insn->off));
|
|
CONT;
|
|
STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
|
|
atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
|
|
(DST + insn->off));
|
|
CONT;
|
|
LD_ABS_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + imm32)) */
|
|
off = IMM;
|
|
load_word:
|
|
/* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are
|
|
* only appearing in the programs where ctx ==
|
|
* skb. All programs keep 'ctx' in regs[BPF_REG_CTX]
|
|
* == BPF_R6, bpf_convert_filter() saves it in BPF_R6,
|
|
* internal BPF verifier will check that BPF_R6 ==
|
|
* ctx.
|
|
*
|
|
* BPF_ABS and BPF_IND are wrappers of function calls,
|
|
* so they scratch BPF_R1-BPF_R5 registers, preserve
|
|
* BPF_R6-BPF_R9, and store return value into BPF_R0.
|
|
*
|
|
* Implicit input:
|
|
* ctx == skb == BPF_R6 == CTX
|
|
*
|
|
* Explicit input:
|
|
* SRC == any register
|
|
* IMM == 32-bit immediate
|
|
*
|
|
* Output:
|
|
* BPF_R0 - 8/16/32-bit skb data converted to cpu endianness
|
|
*/
|
|
|
|
ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 4, &tmp);
|
|
if (likely(ptr != NULL)) {
|
|
BPF_R0 = get_unaligned_be32(ptr);
|
|
CONT;
|
|
}
|
|
|
|
return 0;
|
|
LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + imm32)) */
|
|
off = IMM;
|
|
load_half:
|
|
ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp);
|
|
if (likely(ptr != NULL)) {
|
|
BPF_R0 = get_unaligned_be16(ptr);
|
|
CONT;
|
|
}
|
|
|
|
return 0;
|
|
LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */
|
|
off = IMM;
|
|
load_byte:
|
|
ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp);
|
|
if (likely(ptr != NULL)) {
|
|
BPF_R0 = *(u8 *)ptr;
|
|
CONT;
|
|
}
|
|
|
|
return 0;
|
|
LD_IND_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + src_reg + imm32)) */
|
|
off = IMM + SRC;
|
|
goto load_word;
|
|
LD_IND_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + src_reg + imm32)) */
|
|
off = IMM + SRC;
|
|
goto load_half;
|
|
LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + src_reg + imm32) */
|
|
off = IMM + SRC;
|
|
goto load_byte;
|
|
|
|
default_label:
|
|
/* If we ever reach this, we have a bug somewhere. */
|
|
WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code);
|
|
return 0;
|
|
}
|
|
STACK_FRAME_NON_STANDARD(__bpf_prog_run); /* jump table */
|
|
|
|
bool bpf_prog_array_compatible(struct bpf_array *array,
|
|
const struct bpf_prog *fp)
|
|
{
|
|
if (!array->owner_prog_type) {
|
|
/* There's no owner yet where we could check for
|
|
* compatibility.
|
|
*/
|
|
array->owner_prog_type = fp->type;
|
|
array->owner_jited = fp->jited;
|
|
|
|
return true;
|
|
}
|
|
|
|
return array->owner_prog_type == fp->type &&
|
|
array->owner_jited == fp->jited;
|
|
}
|
|
|
|
static int bpf_check_tail_call(const struct bpf_prog *fp)
|
|
{
|
|
struct bpf_prog_aux *aux = fp->aux;
|
|
int i;
|
|
|
|
for (i = 0; i < aux->used_map_cnt; i++) {
|
|
struct bpf_map *map = aux->used_maps[i];
|
|
struct bpf_array *array;
|
|
|
|
if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY)
|
|
continue;
|
|
|
|
array = container_of(map, struct bpf_array, map);
|
|
if (!bpf_prog_array_compatible(array, fp))
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* bpf_prog_select_runtime - select exec runtime for BPF program
|
|
* @fp: bpf_prog populated with internal BPF program
|
|
* @err: pointer to error variable
|
|
*
|
|
* Try to JIT eBPF program, if JIT is not available, use interpreter.
|
|
* The BPF program will be executed via BPF_PROG_RUN() macro.
|
|
*/
|
|
struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
|
|
{
|
|
fp->bpf_func = (void *) __bpf_prog_run;
|
|
|
|
/* eBPF JITs can rewrite the program in case constant
|
|
* blinding is active. However, in case of error during
|
|
* blinding, bpf_int_jit_compile() must always return a
|
|
* valid program, which in this case would simply not
|
|
* be JITed, but falls back to the interpreter.
|
|
*/
|
|
fp = bpf_int_jit_compile(fp);
|
|
bpf_prog_lock_ro(fp);
|
|
|
|
/* The tail call compatibility check can only be done at
|
|
* this late stage as we need to determine, if we deal
|
|
* with JITed or non JITed program concatenations and not
|
|
* all eBPF JITs might immediately support all features.
|
|
*/
|
|
*err = bpf_check_tail_call(fp);
|
|
|
|
return fp;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_select_runtime);
|
|
|
|
static void bpf_prog_free_deferred(struct work_struct *work)
|
|
{
|
|
struct bpf_prog_aux *aux;
|
|
|
|
aux = container_of(work, struct bpf_prog_aux, work);
|
|
bpf_jit_free(aux->prog);
|
|
}
|
|
|
|
/* Free internal BPF program */
|
|
void bpf_prog_free(struct bpf_prog *fp)
|
|
{
|
|
struct bpf_prog_aux *aux = fp->aux;
|
|
|
|
INIT_WORK(&aux->work, bpf_prog_free_deferred);
|
|
schedule_work(&aux->work);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_free);
|
|
|
|
/* RNG for unpriviledged user space with separated state from prandom_u32(). */
|
|
static DEFINE_PER_CPU(struct rnd_state, bpf_user_rnd_state);
|
|
|
|
void bpf_user_rnd_init_once(void)
|
|
{
|
|
prandom_init_once(&bpf_user_rnd_state);
|
|
}
|
|
|
|
BPF_CALL_0(bpf_user_rnd_u32)
|
|
{
|
|
/* Should someone ever have the rather unwise idea to use some
|
|
* of the registers passed into this function, then note that
|
|
* this function is called from native eBPF and classic-to-eBPF
|
|
* transformations. Register assignments from both sides are
|
|
* different, f.e. classic always sets fn(ctx, A, X) here.
|
|
*/
|
|
struct rnd_state *state;
|
|
u32 res;
|
|
|
|
state = &get_cpu_var(bpf_user_rnd_state);
|
|
res = prandom_u32_state(state);
|
|
put_cpu_var(bpf_user_rnd_state);
|
|
|
|
return res;
|
|
}
|
|
|
|
/* Weak definitions of helper functions in case we don't have bpf syscall. */
|
|
const struct bpf_func_proto bpf_map_lookup_elem_proto __weak;
|
|
const struct bpf_func_proto bpf_map_update_elem_proto __weak;
|
|
const struct bpf_func_proto bpf_map_delete_elem_proto __weak;
|
|
|
|
const struct bpf_func_proto bpf_get_prandom_u32_proto __weak;
|
|
const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak;
|
|
const struct bpf_func_proto bpf_get_numa_node_id_proto __weak;
|
|
const struct bpf_func_proto bpf_ktime_get_ns_proto __weak;
|
|
|
|
const struct bpf_func_proto bpf_get_current_pid_tgid_proto __weak;
|
|
const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak;
|
|
const struct bpf_func_proto bpf_get_current_comm_proto __weak;
|
|
|
|
const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
u64 __weak
|
|
bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
|
|
void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
|
|
{
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
/* Always built-in helper functions. */
|
|
const struct bpf_func_proto bpf_tail_call_proto = {
|
|
.func = NULL,
|
|
.gpl_only = false,
|
|
.ret_type = RET_VOID,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_ANYTHING,
|
|
};
|
|
|
|
/* For classic BPF JITs that don't implement bpf_int_jit_compile(). */
|
|
struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog)
|
|
{
|
|
return prog;
|
|
}
|
|
|
|
bool __weak bpf_helper_changes_pkt_data(void *func)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/* To execute LD_ABS/LD_IND instructions __bpf_prog_run() may call
|
|
* skb_copy_bits(), so provide a weak definition of it for NET-less config.
|
|
*/
|
|
int __weak skb_copy_bits(const struct sk_buff *skb, int offset, void *to,
|
|
int len)
|
|
{
|
|
return -EFAULT;
|
|
}
|