965931e3a8
Commit394e40a297
("bpf: extend bpf_prog_array to store pointers to the cgroup storage") refactored the bpf_prog_array_copy_core() to accommodate new structure bpf_prog_array_item which contains bpf_prog array itself. In the old code, we had perf_event_query_prog_array(): mutex_lock(...) bpf_prog_array_copy_call(): prog = rcu_dereference_check(array, 1)->progs bpf_prog_array_copy_core(prog, ...) mutex_unlock(...) With the above commit, we had perf_event_query_prog_array(): mutex_lock(...) bpf_prog_array_copy_call(): bpf_prog_array_copy_core(array, ...): item = rcu_dereference(array)->items; ... mutex_unlock(...) The new code will trigger a lockdep rcu checking warning. The fix is to change rcu_dereference() to rcu_dereference_check() to prevent such a warning. Reported-by: syzbot+6e72317008eef84a216b@syzkaller.appspotmail.com Fixes:394e40a297
("bpf: extend bpf_prog_array to store pointers to the cgroup storage") Cc: Roman Gushchin <guro@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Roman Gushchin <guro@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
1858 lines
46 KiB
C
1858 lines
46 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 <linux/rbtree_latch.h>
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#include <linux/kallsyms.h>
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#include <linux/rcupdate.h>
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#include <linux/perf_event.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_ZERO | 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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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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fp->jit_requested = ebpf_jit_enabled();
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INIT_LIST_HEAD_RCU(&fp->aux->ksym_lnode);
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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_ZERO | 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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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_tag(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_tag_scratch_size(fp);
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u32 digest[SHA_DIGEST_WORDS];
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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(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(digest, todo, ws);
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todo += SHA_MESSAGE_BYTES;
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}
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result = (__force __be32 *)digest;
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for (i = 0; i < SHA_DIGEST_WORDS; i++)
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result[i] = cpu_to_be32(digest[i]);
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memcpy(fp->tag, result, sizeof(fp->tag));
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vfree(raw);
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return 0;
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}
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static int bpf_adj_delta_to_imm(struct bpf_insn *insn, u32 pos, u32 delta,
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u32 curr, const bool probe_pass)
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{
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const s64 imm_min = S32_MIN, imm_max = S32_MAX;
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s64 imm = insn->imm;
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if (curr < pos && curr + imm + 1 > pos)
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imm += delta;
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else if (curr > pos + delta && curr + imm + 1 <= pos + delta)
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imm -= delta;
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if (imm < imm_min || imm > imm_max)
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return -ERANGE;
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if (!probe_pass)
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insn->imm = imm;
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return 0;
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}
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static int bpf_adj_delta_to_off(struct bpf_insn *insn, u32 pos, u32 delta,
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u32 curr, const bool probe_pass)
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{
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const s32 off_min = S16_MIN, off_max = S16_MAX;
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s32 off = insn->off;
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if (curr < pos && curr + off + 1 > pos)
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off += delta;
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else if (curr > pos + delta && curr + off + 1 <= pos + delta)
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off -= delta;
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if (off < off_min || off > off_max)
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return -ERANGE;
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if (!probe_pass)
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insn->off = off;
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return 0;
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}
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static int bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta,
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const bool probe_pass)
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{
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u32 i, insn_cnt = prog->len + (probe_pass ? delta : 0);
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struct bpf_insn *insn = prog->insnsi;
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int ret = 0;
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for (i = 0; i < insn_cnt; i++, insn++) {
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u8 code;
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/* In the probing pass we still operate on the original,
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* unpatched image in order to check overflows before we
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* do any other adjustments. Therefore skip the patchlet.
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*/
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if (probe_pass && i == pos) {
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i += delta + 1;
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insn++;
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}
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code = insn->code;
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if (BPF_CLASS(code) != BPF_JMP ||
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BPF_OP(code) == BPF_EXIT)
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continue;
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/* Adjust offset of jmps if we cross patch boundaries. */
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if (BPF_OP(code) == BPF_CALL) {
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if (insn->src_reg != BPF_PSEUDO_CALL)
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continue;
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ret = bpf_adj_delta_to_imm(insn, pos, delta, i,
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probe_pass);
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} else {
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ret = bpf_adj_delta_to_off(insn, pos, delta, i,
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probe_pass);
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}
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if (ret)
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break;
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}
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return ret;
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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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const u32 cnt_max = S16_MAX;
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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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/* Reject anything that would potentially let the insn->off
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* target overflow when we have excessive program expansions.
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* We need to probe here before we do any reallocation where
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* we afterwards may not fail anymore.
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*/
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if (insn_adj_cnt > cnt_max &&
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bpf_adj_branches(prog, off, insn_delta, true))
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return NULL;
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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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/* We are guaranteed to not fail at this point, otherwise
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* the ship has sailed to reverse to the original state. An
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* overflow cannot happen at this point.
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*/
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BUG_ON(bpf_adj_branches(prog_adj, off, insn_delta, false));
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return prog_adj;
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}
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void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp)
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{
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int i;
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for (i = 0; i < fp->aux->func_cnt; i++)
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bpf_prog_kallsyms_del(fp->aux->func[i]);
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}
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void bpf_prog_kallsyms_del_all(struct bpf_prog *fp)
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{
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bpf_prog_kallsyms_del_subprogs(fp);
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bpf_prog_kallsyms_del(fp);
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}
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#ifdef CONFIG_BPF_JIT
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/* All BPF JIT sysctl knobs here. */
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int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON);
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int bpf_jit_harden __read_mostly;
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int bpf_jit_kallsyms __read_mostly;
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static __always_inline void
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bpf_get_prog_addr_region(const struct bpf_prog *prog,
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unsigned long *symbol_start,
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unsigned long *symbol_end)
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{
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const struct bpf_binary_header *hdr = bpf_jit_binary_hdr(prog);
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unsigned long addr = (unsigned long)hdr;
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WARN_ON_ONCE(!bpf_prog_ebpf_jited(prog));
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*symbol_start = addr;
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*symbol_end = addr + hdr->pages * PAGE_SIZE;
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}
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static void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
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{
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const char *end = sym + KSYM_NAME_LEN;
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BUILD_BUG_ON(sizeof("bpf_prog_") +
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sizeof(prog->tag) * 2 +
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/* name has been null terminated.
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* We should need +1 for the '_' preceding
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* the name. However, the null character
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* is double counted between the name and the
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* sizeof("bpf_prog_") above, so we omit
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* the +1 here.
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*/
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sizeof(prog->aux->name) > KSYM_NAME_LEN);
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sym += snprintf(sym, KSYM_NAME_LEN, "bpf_prog_");
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sym = bin2hex(sym, prog->tag, sizeof(prog->tag));
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if (prog->aux->name[0])
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snprintf(sym, (size_t)(end - sym), "_%s", prog->aux->name);
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else
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*sym = 0;
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}
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static __always_inline unsigned long
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bpf_get_prog_addr_start(struct latch_tree_node *n)
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{
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unsigned long symbol_start, symbol_end;
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const struct bpf_prog_aux *aux;
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aux = container_of(n, struct bpf_prog_aux, ksym_tnode);
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bpf_get_prog_addr_region(aux->prog, &symbol_start, &symbol_end);
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return symbol_start;
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}
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static __always_inline bool bpf_tree_less(struct latch_tree_node *a,
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struct latch_tree_node *b)
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{
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return bpf_get_prog_addr_start(a) < bpf_get_prog_addr_start(b);
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}
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static __always_inline int bpf_tree_comp(void *key, struct latch_tree_node *n)
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{
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unsigned long val = (unsigned long)key;
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unsigned long symbol_start, symbol_end;
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const struct bpf_prog_aux *aux;
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aux = container_of(n, struct bpf_prog_aux, ksym_tnode);
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bpf_get_prog_addr_region(aux->prog, &symbol_start, &symbol_end);
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if (val < symbol_start)
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return -1;
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if (val >= symbol_end)
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return 1;
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return 0;
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}
|
|
|
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static const struct latch_tree_ops bpf_tree_ops = {
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.less = bpf_tree_less,
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.comp = bpf_tree_comp,
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};
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|
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static DEFINE_SPINLOCK(bpf_lock);
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static LIST_HEAD(bpf_kallsyms);
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static struct latch_tree_root bpf_tree __cacheline_aligned;
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|
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static void bpf_prog_ksym_node_add(struct bpf_prog_aux *aux)
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{
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WARN_ON_ONCE(!list_empty(&aux->ksym_lnode));
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list_add_tail_rcu(&aux->ksym_lnode, &bpf_kallsyms);
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latch_tree_insert(&aux->ksym_tnode, &bpf_tree, &bpf_tree_ops);
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}
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static void bpf_prog_ksym_node_del(struct bpf_prog_aux *aux)
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{
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if (list_empty(&aux->ksym_lnode))
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return;
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|
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latch_tree_erase(&aux->ksym_tnode, &bpf_tree, &bpf_tree_ops);
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list_del_rcu(&aux->ksym_lnode);
|
|
}
|
|
|
|
static bool bpf_prog_kallsyms_candidate(const struct bpf_prog *fp)
|
|
{
|
|
return fp->jited && !bpf_prog_was_classic(fp);
|
|
}
|
|
|
|
static bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp)
|
|
{
|
|
return list_empty(&fp->aux->ksym_lnode) ||
|
|
fp->aux->ksym_lnode.prev == LIST_POISON2;
|
|
}
|
|
|
|
void bpf_prog_kallsyms_add(struct bpf_prog *fp)
|
|
{
|
|
if (!bpf_prog_kallsyms_candidate(fp) ||
|
|
!capable(CAP_SYS_ADMIN))
|
|
return;
|
|
|
|
spin_lock_bh(&bpf_lock);
|
|
bpf_prog_ksym_node_add(fp->aux);
|
|
spin_unlock_bh(&bpf_lock);
|
|
}
|
|
|
|
void bpf_prog_kallsyms_del(struct bpf_prog *fp)
|
|
{
|
|
if (!bpf_prog_kallsyms_candidate(fp))
|
|
return;
|
|
|
|
spin_lock_bh(&bpf_lock);
|
|
bpf_prog_ksym_node_del(fp->aux);
|
|
spin_unlock_bh(&bpf_lock);
|
|
}
|
|
|
|
static struct bpf_prog *bpf_prog_kallsyms_find(unsigned long addr)
|
|
{
|
|
struct latch_tree_node *n;
|
|
|
|
if (!bpf_jit_kallsyms_enabled())
|
|
return NULL;
|
|
|
|
n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops);
|
|
return n ?
|
|
container_of(n, struct bpf_prog_aux, ksym_tnode)->prog :
|
|
NULL;
|
|
}
|
|
|
|
const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
|
|
unsigned long *off, char *sym)
|
|
{
|
|
unsigned long symbol_start, symbol_end;
|
|
struct bpf_prog *prog;
|
|
char *ret = NULL;
|
|
|
|
rcu_read_lock();
|
|
prog = bpf_prog_kallsyms_find(addr);
|
|
if (prog) {
|
|
bpf_get_prog_addr_region(prog, &symbol_start, &symbol_end);
|
|
bpf_get_prog_name(prog, sym);
|
|
|
|
ret = sym;
|
|
if (size)
|
|
*size = symbol_end - symbol_start;
|
|
if (off)
|
|
*off = addr - symbol_start;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
bool is_bpf_text_address(unsigned long addr)
|
|
{
|
|
bool ret;
|
|
|
|
rcu_read_lock();
|
|
ret = bpf_prog_kallsyms_find(addr) != NULL;
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
|
|
char *sym)
|
|
{
|
|
unsigned long symbol_start, symbol_end;
|
|
struct bpf_prog_aux *aux;
|
|
unsigned int it = 0;
|
|
int ret = -ERANGE;
|
|
|
|
if (!bpf_jit_kallsyms_enabled())
|
|
return ret;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(aux, &bpf_kallsyms, ksym_lnode) {
|
|
if (it++ != symnum)
|
|
continue;
|
|
|
|
bpf_get_prog_addr_region(aux->prog, &symbol_start, &symbol_end);
|
|
bpf_get_prog_name(aux->prog, sym);
|
|
|
|
*value = symbol_start;
|
|
*type = BPF_SYM_ELF_TYPE;
|
|
|
|
ret = 0;
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
struct bpf_binary_header *
|
|
bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
|
|
unsigned int alignment,
|
|
bpf_jit_fill_hole_t bpf_fill_ill_insns)
|
|
{
|
|
struct bpf_binary_header *hdr;
|
|
unsigned int size, hole, start;
|
|
|
|
/* Most of BPF filters are really small, but if some of them
|
|
* fill a page, allow at least 128 extra bytes to insert a
|
|
* random section of illegal instructions.
|
|
*/
|
|
size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
|
|
hdr = module_alloc(size);
|
|
if (hdr == NULL)
|
|
return NULL;
|
|
|
|
/* Fill space with illegal/arch-dep instructions. */
|
|
bpf_fill_ill_insns(hdr, size);
|
|
|
|
hdr->pages = size / PAGE_SIZE;
|
|
hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)),
|
|
PAGE_SIZE - sizeof(*hdr));
|
|
start = (get_random_int() % hole) & ~(alignment - 1);
|
|
|
|
/* Leave a random number of instructions before BPF code. */
|
|
*image_ptr = &hdr->image[start];
|
|
|
|
return hdr;
|
|
}
|
|
|
|
void bpf_jit_binary_free(struct bpf_binary_header *hdr)
|
|
{
|
|
module_memfree(hdr);
|
|
}
|
|
|
|
/* This symbol is only overridden by archs that have different
|
|
* requirements than the usual eBPF JITs, f.e. when they only
|
|
* implement cBPF JIT, do not set images read-only, etc.
|
|
*/
|
|
void __weak bpf_jit_free(struct bpf_prog *fp)
|
|
{
|
|
if (fp->jited) {
|
|
struct bpf_binary_header *hdr = bpf_jit_binary_hdr(fp);
|
|
|
|
bpf_jit_binary_unlock_ro(hdr);
|
|
bpf_jit_binary_free(hdr);
|
|
|
|
WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(fp));
|
|
}
|
|
|
|
bpf_prog_unlock_free(fp);
|
|
}
|
|
|
|
static int bpf_jit_blind_insn(const struct bpf_insn *from,
|
|
const struct bpf_insn *aux,
|
|
struct bpf_insn *to_buff)
|
|
{
|
|
struct bpf_insn *to = to_buff;
|
|
u32 imm_rnd = get_random_int();
|
|
s16 off;
|
|
|
|
BUILD_BUG_ON(BPF_REG_AX + 1 != MAX_BPF_JIT_REG);
|
|
BUILD_BUG_ON(MAX_BPF_REG + 1 != MAX_BPF_JIT_REG);
|
|
|
|
if (from->imm == 0 &&
|
|
(from->code == (BPF_ALU | BPF_MOV | BPF_K) ||
|
|
from->code == (BPF_ALU64 | BPF_MOV | BPF_K))) {
|
|
*to++ = BPF_ALU64_REG(BPF_XOR, from->dst_reg, from->dst_reg);
|
|
goto out;
|
|
}
|
|
|
|
switch (from->code) {
|
|
case BPF_ALU | BPF_ADD | BPF_K:
|
|
case BPF_ALU | BPF_SUB | BPF_K:
|
|
case BPF_ALU | BPF_AND | BPF_K:
|
|
case BPF_ALU | BPF_OR | BPF_K:
|
|
case BPF_ALU | BPF_XOR | BPF_K:
|
|
case BPF_ALU | BPF_MUL | BPF_K:
|
|
case BPF_ALU | BPF_MOV | BPF_K:
|
|
case BPF_ALU | BPF_DIV | BPF_K:
|
|
case BPF_ALU | BPF_MOD | BPF_K:
|
|
*to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
|
|
*to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
|
|
*to++ = BPF_ALU32_REG(from->code, from->dst_reg, BPF_REG_AX);
|
|
break;
|
|
|
|
case BPF_ALU64 | BPF_ADD | BPF_K:
|
|
case BPF_ALU64 | BPF_SUB | BPF_K:
|
|
case BPF_ALU64 | BPF_AND | BPF_K:
|
|
case BPF_ALU64 | BPF_OR | BPF_K:
|
|
case BPF_ALU64 | BPF_XOR | BPF_K:
|
|
case BPF_ALU64 | BPF_MUL | BPF_K:
|
|
case BPF_ALU64 | BPF_MOV | BPF_K:
|
|
case BPF_ALU64 | BPF_DIV | BPF_K:
|
|
case BPF_ALU64 | BPF_MOD | BPF_K:
|
|
*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
|
|
*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
|
|
*to++ = BPF_ALU64_REG(from->code, from->dst_reg, BPF_REG_AX);
|
|
break;
|
|
|
|
case BPF_JMP | BPF_JEQ | BPF_K:
|
|
case BPF_JMP | BPF_JNE | BPF_K:
|
|
case BPF_JMP | BPF_JGT | BPF_K:
|
|
case BPF_JMP | BPF_JLT | BPF_K:
|
|
case BPF_JMP | BPF_JGE | BPF_K:
|
|
case BPF_JMP | BPF_JLE | BPF_K:
|
|
case BPF_JMP | BPF_JSGT | BPF_K:
|
|
case BPF_JMP | BPF_JSLT | BPF_K:
|
|
case BPF_JMP | BPF_JSGE | BPF_K:
|
|
case BPF_JMP | BPF_JSLE | BPF_K:
|
|
case BPF_JMP | BPF_JSET | BPF_K:
|
|
/* Accommodate for extra offset in case of a backjump. */
|
|
off = from->off;
|
|
if (off < 0)
|
|
off -= 2;
|
|
*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
|
|
*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
|
|
*to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off);
|
|
break;
|
|
|
|
case BPF_LD | BPF_IMM | BPF_DW:
|
|
*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm);
|
|
*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
|
|
*to++ = BPF_ALU64_IMM(BPF_LSH, BPF_REG_AX, 32);
|
|
*to++ = BPF_ALU64_REG(BPF_MOV, aux[0].dst_reg, BPF_REG_AX);
|
|
break;
|
|
case 0: /* Part 2 of BPF_LD | BPF_IMM | BPF_DW. */
|
|
*to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[0].imm);
|
|
*to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
|
|
*to++ = BPF_ALU64_REG(BPF_OR, aux[0].dst_reg, BPF_REG_AX);
|
|
break;
|
|
|
|
case BPF_ST | BPF_MEM | BPF_DW:
|
|
case BPF_ST | BPF_MEM | BPF_W:
|
|
case BPF_ST | BPF_MEM | BPF_H:
|
|
case BPF_ST | BPF_MEM | BPF_B:
|
|
*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
|
|
*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
|
|
*to++ = BPF_STX_MEM(from->code, from->dst_reg, BPF_REG_AX, from->off);
|
|
break;
|
|
}
|
|
out:
|
|
return to - to_buff;
|
|
}
|
|
|
|
static struct bpf_prog *bpf_prog_clone_create(struct bpf_prog *fp_other,
|
|
gfp_t gfp_extra_flags)
|
|
{
|
|
gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
|
|
struct bpf_prog *fp;
|
|
|
|
fp = __vmalloc(fp_other->pages * PAGE_SIZE, gfp_flags, PAGE_KERNEL);
|
|
if (fp != NULL) {
|
|
/* 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(prog) || prog->blinded)
|
|
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;
|
|
}
|
|
|
|
clone->blinded = 1;
|
|
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. This also needs
|
|
* to go into kallsyms for correlation from e.g. bpftool, so naming
|
|
* must not change.
|
|
*/
|
|
noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
|
|
{
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__bpf_call_base);
|
|
|
|
/* All UAPI available opcodes. */
|
|
#define BPF_INSN_MAP(INSN_2, INSN_3) \
|
|
/* 32 bit ALU operations. */ \
|
|
/* Register based. */ \
|
|
INSN_3(ALU, ADD, X), \
|
|
INSN_3(ALU, SUB, X), \
|
|
INSN_3(ALU, AND, X), \
|
|
INSN_3(ALU, OR, X), \
|
|
INSN_3(ALU, LSH, X), \
|
|
INSN_3(ALU, RSH, X), \
|
|
INSN_3(ALU, XOR, X), \
|
|
INSN_3(ALU, MUL, X), \
|
|
INSN_3(ALU, MOV, X), \
|
|
INSN_3(ALU, DIV, X), \
|
|
INSN_3(ALU, MOD, X), \
|
|
INSN_2(ALU, NEG), \
|
|
INSN_3(ALU, END, TO_BE), \
|
|
INSN_3(ALU, END, TO_LE), \
|
|
/* Immediate based. */ \
|
|
INSN_3(ALU, ADD, K), \
|
|
INSN_3(ALU, SUB, K), \
|
|
INSN_3(ALU, AND, K), \
|
|
INSN_3(ALU, OR, K), \
|
|
INSN_3(ALU, LSH, K), \
|
|
INSN_3(ALU, RSH, K), \
|
|
INSN_3(ALU, XOR, K), \
|
|
INSN_3(ALU, MUL, K), \
|
|
INSN_3(ALU, MOV, K), \
|
|
INSN_3(ALU, DIV, K), \
|
|
INSN_3(ALU, MOD, K), \
|
|
/* 64 bit ALU operations. */ \
|
|
/* Register based. */ \
|
|
INSN_3(ALU64, ADD, X), \
|
|
INSN_3(ALU64, SUB, X), \
|
|
INSN_3(ALU64, AND, X), \
|
|
INSN_3(ALU64, OR, X), \
|
|
INSN_3(ALU64, LSH, X), \
|
|
INSN_3(ALU64, RSH, X), \
|
|
INSN_3(ALU64, XOR, X), \
|
|
INSN_3(ALU64, MUL, X), \
|
|
INSN_3(ALU64, MOV, X), \
|
|
INSN_3(ALU64, ARSH, X), \
|
|
INSN_3(ALU64, DIV, X), \
|
|
INSN_3(ALU64, MOD, X), \
|
|
INSN_2(ALU64, NEG), \
|
|
/* Immediate based. */ \
|
|
INSN_3(ALU64, ADD, K), \
|
|
INSN_3(ALU64, SUB, K), \
|
|
INSN_3(ALU64, AND, K), \
|
|
INSN_3(ALU64, OR, K), \
|
|
INSN_3(ALU64, LSH, K), \
|
|
INSN_3(ALU64, RSH, K), \
|
|
INSN_3(ALU64, XOR, K), \
|
|
INSN_3(ALU64, MUL, K), \
|
|
INSN_3(ALU64, MOV, K), \
|
|
INSN_3(ALU64, ARSH, K), \
|
|
INSN_3(ALU64, DIV, K), \
|
|
INSN_3(ALU64, MOD, K), \
|
|
/* Call instruction. */ \
|
|
INSN_2(JMP, CALL), \
|
|
/* Exit instruction. */ \
|
|
INSN_2(JMP, EXIT), \
|
|
/* Jump instructions. */ \
|
|
/* Register based. */ \
|
|
INSN_3(JMP, JEQ, X), \
|
|
INSN_3(JMP, JNE, X), \
|
|
INSN_3(JMP, JGT, X), \
|
|
INSN_3(JMP, JLT, X), \
|
|
INSN_3(JMP, JGE, X), \
|
|
INSN_3(JMP, JLE, X), \
|
|
INSN_3(JMP, JSGT, X), \
|
|
INSN_3(JMP, JSLT, X), \
|
|
INSN_3(JMP, JSGE, X), \
|
|
INSN_3(JMP, JSLE, X), \
|
|
INSN_3(JMP, JSET, X), \
|
|
/* Immediate based. */ \
|
|
INSN_3(JMP, JEQ, K), \
|
|
INSN_3(JMP, JNE, K), \
|
|
INSN_3(JMP, JGT, K), \
|
|
INSN_3(JMP, JLT, K), \
|
|
INSN_3(JMP, JGE, K), \
|
|
INSN_3(JMP, JLE, K), \
|
|
INSN_3(JMP, JSGT, K), \
|
|
INSN_3(JMP, JSLT, K), \
|
|
INSN_3(JMP, JSGE, K), \
|
|
INSN_3(JMP, JSLE, K), \
|
|
INSN_3(JMP, JSET, K), \
|
|
INSN_2(JMP, JA), \
|
|
/* Store instructions. */ \
|
|
/* Register based. */ \
|
|
INSN_3(STX, MEM, B), \
|
|
INSN_3(STX, MEM, H), \
|
|
INSN_3(STX, MEM, W), \
|
|
INSN_3(STX, MEM, DW), \
|
|
INSN_3(STX, XADD, W), \
|
|
INSN_3(STX, XADD, DW), \
|
|
/* Immediate based. */ \
|
|
INSN_3(ST, MEM, B), \
|
|
INSN_3(ST, MEM, H), \
|
|
INSN_3(ST, MEM, W), \
|
|
INSN_3(ST, MEM, DW), \
|
|
/* Load instructions. */ \
|
|
/* Register based. */ \
|
|
INSN_3(LDX, MEM, B), \
|
|
INSN_3(LDX, MEM, H), \
|
|
INSN_3(LDX, MEM, W), \
|
|
INSN_3(LDX, MEM, DW), \
|
|
/* Immediate based. */ \
|
|
INSN_3(LD, IMM, DW)
|
|
|
|
bool bpf_opcode_in_insntable(u8 code)
|
|
{
|
|
#define BPF_INSN_2_TBL(x, y) [BPF_##x | BPF_##y] = true
|
|
#define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true
|
|
static const bool public_insntable[256] = {
|
|
[0 ... 255] = false,
|
|
/* Now overwrite non-defaults ... */
|
|
BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL),
|
|
/* UAPI exposed, but rewritten opcodes. cBPF carry-over. */
|
|
[BPF_LD | BPF_ABS | BPF_B] = true,
|
|
[BPF_LD | BPF_ABS | BPF_H] = true,
|
|
[BPF_LD | BPF_ABS | BPF_W] = true,
|
|
[BPF_LD | BPF_IND | BPF_B] = true,
|
|
[BPF_LD | BPF_IND | BPF_H] = true,
|
|
[BPF_LD | BPF_IND | BPF_W] = true,
|
|
};
|
|
#undef BPF_INSN_3_TBL
|
|
#undef BPF_INSN_2_TBL
|
|
return public_insntable[code];
|
|
}
|
|
|
|
#ifndef CONFIG_BPF_JIT_ALWAYS_ON
|
|
/**
|
|
* __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 u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
|
|
{
|
|
u64 tmp;
|
|
#define BPF_INSN_2_LBL(x, y) [BPF_##x | BPF_##y] = &&x##_##y
|
|
#define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z
|
|
static const void *jumptable[256] = {
|
|
[0 ... 255] = &&default_label,
|
|
/* Now overwrite non-defaults ... */
|
|
BPF_INSN_MAP(BPF_INSN_2_LBL, BPF_INSN_3_LBL),
|
|
/* Non-UAPI available opcodes. */
|
|
[BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS,
|
|
[BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL,
|
|
};
|
|
#undef BPF_INSN_3_LBL
|
|
#undef BPF_INSN_2_LBL
|
|
u32 tail_call_cnt = 0;
|
|
|
|
#define CONT ({ insn++; goto select_insn; })
|
|
#define CONT_JMP ({ insn++; goto select_insn; })
|
|
|
|
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:
|
|
div64_u64_rem(DST, SRC, &tmp);
|
|
DST = tmp;
|
|
CONT;
|
|
ALU_MOD_X:
|
|
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:
|
|
DST = div64_u64(DST, SRC);
|
|
CONT;
|
|
ALU_DIV_X:
|
|
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_CALL_ARGS:
|
|
BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2,
|
|
BPF_R3, BPF_R4,
|
|
BPF_R5,
|
|
insn + insn->off + 1);
|
|
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;
|
|
u32 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_JLT_X:
|
|
if (DST < SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JLT_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_JLE_X:
|
|
if (DST <= SRC) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JLE_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_JSLT_X:
|
|
if (((s64) DST) < ((s64) SRC)) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSLT_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_JSLE_X:
|
|
if (((s64) DST) <= ((s64) SRC)) {
|
|
insn += insn->off;
|
|
CONT_JMP;
|
|
}
|
|
CONT;
|
|
JMP_JSLE_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;
|
|
|
|
default_label:
|
|
/* If we ever reach this, we have a bug somewhere. Die hard here
|
|
* instead of just returning 0; we could be somewhere in a subprog,
|
|
* so execution could continue otherwise which we do /not/ want.
|
|
*
|
|
* Note, verifier whitelists all opcodes in bpf_opcode_in_insntable().
|
|
*/
|
|
pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code);
|
|
BUG_ON(1);
|
|
return 0;
|
|
}
|
|
STACK_FRAME_NON_STANDARD(___bpf_prog_run); /* jump table */
|
|
|
|
#define PROG_NAME(stack_size) __bpf_prog_run##stack_size
|
|
#define DEFINE_BPF_PROG_RUN(stack_size) \
|
|
static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn *insn) \
|
|
{ \
|
|
u64 stack[stack_size / sizeof(u64)]; \
|
|
u64 regs[MAX_BPF_REG]; \
|
|
\
|
|
FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \
|
|
ARG1 = (u64) (unsigned long) ctx; \
|
|
return ___bpf_prog_run(regs, insn, stack); \
|
|
}
|
|
|
|
#define PROG_NAME_ARGS(stack_size) __bpf_prog_run_args##stack_size
|
|
#define DEFINE_BPF_PROG_RUN_ARGS(stack_size) \
|
|
static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \
|
|
const struct bpf_insn *insn) \
|
|
{ \
|
|
u64 stack[stack_size / sizeof(u64)]; \
|
|
u64 regs[MAX_BPF_REG]; \
|
|
\
|
|
FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \
|
|
BPF_R1 = r1; \
|
|
BPF_R2 = r2; \
|
|
BPF_R3 = r3; \
|
|
BPF_R4 = r4; \
|
|
BPF_R5 = r5; \
|
|
return ___bpf_prog_run(regs, insn, stack); \
|
|
}
|
|
|
|
#define EVAL1(FN, X) FN(X)
|
|
#define EVAL2(FN, X, Y...) FN(X) EVAL1(FN, Y)
|
|
#define EVAL3(FN, X, Y...) FN(X) EVAL2(FN, Y)
|
|
#define EVAL4(FN, X, Y...) FN(X) EVAL3(FN, Y)
|
|
#define EVAL5(FN, X, Y...) FN(X) EVAL4(FN, Y)
|
|
#define EVAL6(FN, X, Y...) FN(X) EVAL5(FN, Y)
|
|
|
|
EVAL6(DEFINE_BPF_PROG_RUN, 32, 64, 96, 128, 160, 192);
|
|
EVAL6(DEFINE_BPF_PROG_RUN, 224, 256, 288, 320, 352, 384);
|
|
EVAL4(DEFINE_BPF_PROG_RUN, 416, 448, 480, 512);
|
|
|
|
EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 32, 64, 96, 128, 160, 192);
|
|
EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 224, 256, 288, 320, 352, 384);
|
|
EVAL4(DEFINE_BPF_PROG_RUN_ARGS, 416, 448, 480, 512);
|
|
|
|
#define PROG_NAME_LIST(stack_size) PROG_NAME(stack_size),
|
|
|
|
static unsigned int (*interpreters[])(const void *ctx,
|
|
const struct bpf_insn *insn) = {
|
|
EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
|
|
EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
|
|
EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
|
|
};
|
|
#undef PROG_NAME_LIST
|
|
#define PROG_NAME_LIST(stack_size) PROG_NAME_ARGS(stack_size),
|
|
static u64 (*interpreters_args[])(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5,
|
|
const struct bpf_insn *insn) = {
|
|
EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
|
|
EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
|
|
EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
|
|
};
|
|
#undef PROG_NAME_LIST
|
|
|
|
void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth)
|
|
{
|
|
stack_depth = max_t(u32, stack_depth, 1);
|
|
insn->off = (s16) insn->imm;
|
|
insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] -
|
|
__bpf_call_base_args;
|
|
insn->code = BPF_JMP | BPF_CALL_ARGS;
|
|
}
|
|
|
|
#else
|
|
static unsigned int __bpf_prog_ret0_warn(const void *ctx,
|
|
const struct bpf_insn *insn)
|
|
{
|
|
/* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON
|
|
* is not working properly, so warn about it!
|
|
*/
|
|
WARN_ON_ONCE(1);
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
bool bpf_prog_array_compatible(struct bpf_array *array,
|
|
const struct bpf_prog *fp)
|
|
{
|
|
if (fp->kprobe_override)
|
|
return false;
|
|
|
|
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;
|
|
}
|
|
|
|
static void bpf_prog_select_func(struct bpf_prog *fp)
|
|
{
|
|
#ifndef CONFIG_BPF_JIT_ALWAYS_ON
|
|
u32 stack_depth = max_t(u32, fp->aux->stack_depth, 1);
|
|
|
|
fp->bpf_func = interpreters[(round_up(stack_depth, 32) / 32) - 1];
|
|
#else
|
|
fp->bpf_func = __bpf_prog_ret0_warn;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
/* In case of BPF to BPF calls, verifier did all the prep
|
|
* work with regards to JITing, etc.
|
|
*/
|
|
if (fp->bpf_func)
|
|
goto finalize;
|
|
|
|
bpf_prog_select_func(fp);
|
|
|
|
/* 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.
|
|
*/
|
|
if (!bpf_prog_is_dev_bound(fp->aux)) {
|
|
fp = bpf_int_jit_compile(fp);
|
|
#ifdef CONFIG_BPF_JIT_ALWAYS_ON
|
|
if (!fp->jited) {
|
|
*err = -ENOTSUPP;
|
|
return fp;
|
|
}
|
|
#endif
|
|
} else {
|
|
*err = bpf_prog_offload_compile(fp);
|
|
if (*err)
|
|
return fp;
|
|
}
|
|
|
|
finalize:
|
|
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 unsigned int __bpf_prog_ret1(const void *ctx,
|
|
const struct bpf_insn *insn)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static struct bpf_prog_dummy {
|
|
struct bpf_prog prog;
|
|
} dummy_bpf_prog = {
|
|
.prog = {
|
|
.bpf_func = __bpf_prog_ret1,
|
|
},
|
|
};
|
|
|
|
/* to avoid allocating empty bpf_prog_array for cgroups that
|
|
* don't have bpf program attached use one global 'empty_prog_array'
|
|
* It will not be modified the caller of bpf_prog_array_alloc()
|
|
* (since caller requested prog_cnt == 0)
|
|
* that pointer should be 'freed' by bpf_prog_array_free()
|
|
*/
|
|
static struct {
|
|
struct bpf_prog_array hdr;
|
|
struct bpf_prog *null_prog;
|
|
} empty_prog_array = {
|
|
.null_prog = NULL,
|
|
};
|
|
|
|
struct bpf_prog_array *bpf_prog_array_alloc(u32 prog_cnt, gfp_t flags)
|
|
{
|
|
if (prog_cnt)
|
|
return kzalloc(sizeof(struct bpf_prog_array) +
|
|
sizeof(struct bpf_prog_array_item) *
|
|
(prog_cnt + 1),
|
|
flags);
|
|
|
|
return &empty_prog_array.hdr;
|
|
}
|
|
|
|
void bpf_prog_array_free(struct bpf_prog_array __rcu *progs)
|
|
{
|
|
if (!progs ||
|
|
progs == (struct bpf_prog_array __rcu *)&empty_prog_array.hdr)
|
|
return;
|
|
kfree_rcu(progs, rcu);
|
|
}
|
|
|
|
int bpf_prog_array_length(struct bpf_prog_array __rcu *array)
|
|
{
|
|
struct bpf_prog_array_item *item;
|
|
u32 cnt = 0;
|
|
|
|
rcu_read_lock();
|
|
item = rcu_dereference(array)->items;
|
|
for (; item->prog; item++)
|
|
if (item->prog != &dummy_bpf_prog.prog)
|
|
cnt++;
|
|
rcu_read_unlock();
|
|
return cnt;
|
|
}
|
|
|
|
|
|
static bool bpf_prog_array_copy_core(struct bpf_prog_array __rcu *array,
|
|
u32 *prog_ids,
|
|
u32 request_cnt)
|
|
{
|
|
struct bpf_prog_array_item *item;
|
|
int i = 0;
|
|
|
|
item = rcu_dereference_check(array, 1)->items;
|
|
for (; item->prog; item++) {
|
|
if (item->prog == &dummy_bpf_prog.prog)
|
|
continue;
|
|
prog_ids[i] = item->prog->aux->id;
|
|
if (++i == request_cnt) {
|
|
item++;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return !!(item->prog);
|
|
}
|
|
|
|
int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *array,
|
|
__u32 __user *prog_ids, u32 cnt)
|
|
{
|
|
unsigned long err = 0;
|
|
bool nospc;
|
|
u32 *ids;
|
|
|
|
/* users of this function are doing:
|
|
* cnt = bpf_prog_array_length();
|
|
* if (cnt > 0)
|
|
* bpf_prog_array_copy_to_user(..., cnt);
|
|
* so below kcalloc doesn't need extra cnt > 0 check, but
|
|
* bpf_prog_array_length() releases rcu lock and
|
|
* prog array could have been swapped with empty or larger array,
|
|
* so always copy 'cnt' prog_ids to the user.
|
|
* In a rare race the user will see zero prog_ids
|
|
*/
|
|
ids = kcalloc(cnt, sizeof(u32), GFP_USER | __GFP_NOWARN);
|
|
if (!ids)
|
|
return -ENOMEM;
|
|
rcu_read_lock();
|
|
nospc = bpf_prog_array_copy_core(array, ids, cnt);
|
|
rcu_read_unlock();
|
|
err = copy_to_user(prog_ids, ids, cnt * sizeof(u32));
|
|
kfree(ids);
|
|
if (err)
|
|
return -EFAULT;
|
|
if (nospc)
|
|
return -ENOSPC;
|
|
return 0;
|
|
}
|
|
|
|
void bpf_prog_array_delete_safe(struct bpf_prog_array __rcu *array,
|
|
struct bpf_prog *old_prog)
|
|
{
|
|
struct bpf_prog_array_item *item = array->items;
|
|
|
|
for (; item->prog; item++)
|
|
if (item->prog == old_prog) {
|
|
WRITE_ONCE(item->prog, &dummy_bpf_prog.prog);
|
|
break;
|
|
}
|
|
}
|
|
|
|
int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
|
|
struct bpf_prog *exclude_prog,
|
|
struct bpf_prog *include_prog,
|
|
struct bpf_prog_array **new_array)
|
|
{
|
|
int new_prog_cnt, carry_prog_cnt = 0;
|
|
struct bpf_prog_array_item *existing;
|
|
struct bpf_prog_array *array;
|
|
bool found_exclude = false;
|
|
int new_prog_idx = 0;
|
|
|
|
/* Figure out how many existing progs we need to carry over to
|
|
* the new array.
|
|
*/
|
|
if (old_array) {
|
|
existing = old_array->items;
|
|
for (; existing->prog; existing++) {
|
|
if (existing->prog == exclude_prog) {
|
|
found_exclude = true;
|
|
continue;
|
|
}
|
|
if (existing->prog != &dummy_bpf_prog.prog)
|
|
carry_prog_cnt++;
|
|
if (existing->prog == include_prog)
|
|
return -EEXIST;
|
|
}
|
|
}
|
|
|
|
if (exclude_prog && !found_exclude)
|
|
return -ENOENT;
|
|
|
|
/* How many progs (not NULL) will be in the new array? */
|
|
new_prog_cnt = carry_prog_cnt;
|
|
if (include_prog)
|
|
new_prog_cnt += 1;
|
|
|
|
/* Do we have any prog (not NULL) in the new array? */
|
|
if (!new_prog_cnt) {
|
|
*new_array = NULL;
|
|
return 0;
|
|
}
|
|
|
|
/* +1 as the end of prog_array is marked with NULL */
|
|
array = bpf_prog_array_alloc(new_prog_cnt + 1, GFP_KERNEL);
|
|
if (!array)
|
|
return -ENOMEM;
|
|
|
|
/* Fill in the new prog array */
|
|
if (carry_prog_cnt) {
|
|
existing = old_array->items;
|
|
for (; existing->prog; existing++)
|
|
if (existing->prog != exclude_prog &&
|
|
existing->prog != &dummy_bpf_prog.prog) {
|
|
array->items[new_prog_idx++].prog =
|
|
existing->prog;
|
|
}
|
|
}
|
|
if (include_prog)
|
|
array->items[new_prog_idx++].prog = include_prog;
|
|
array->items[new_prog_idx].prog = NULL;
|
|
*new_array = array;
|
|
return 0;
|
|
}
|
|
|
|
int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array,
|
|
u32 *prog_ids, u32 request_cnt,
|
|
u32 *prog_cnt)
|
|
{
|
|
u32 cnt = 0;
|
|
|
|
if (array)
|
|
cnt = bpf_prog_array_length(array);
|
|
|
|
*prog_cnt = cnt;
|
|
|
|
/* return early if user requested only program count or nothing to copy */
|
|
if (!request_cnt || !cnt)
|
|
return 0;
|
|
|
|
/* this function is called under trace/bpf_trace.c: bpf_event_mutex */
|
|
return bpf_prog_array_copy_core(array, prog_ids, request_cnt) ? -ENOSPC
|
|
: 0;
|
|
}
|
|
|
|
static void bpf_prog_free_deferred(struct work_struct *work)
|
|
{
|
|
struct bpf_prog_aux *aux;
|
|
int i;
|
|
|
|
aux = container_of(work, struct bpf_prog_aux, work);
|
|
if (bpf_prog_is_dev_bound(aux))
|
|
bpf_prog_offload_destroy(aux->prog);
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
if (aux->prog->has_callchain_buf)
|
|
put_callchain_buffers();
|
|
#endif
|
|
for (i = 0; i < aux->func_cnt; i++)
|
|
bpf_jit_free(aux->func[i]);
|
|
if (aux->func_cnt) {
|
|
kfree(aux->func);
|
|
bpf_prog_unlock_free(aux->prog);
|
|
} else {
|
|
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 bpf_sock_map_update_proto __weak;
|
|
const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
|
|
const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak;
|
|
const struct bpf_func_proto bpf_get_local_storage_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;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_event_output);
|
|
|
|
/* 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,
|
|
};
|
|
|
|
/* Stub for JITs that only support cBPF. eBPF programs are interpreted.
|
|
* It is encouraged to implement bpf_int_jit_compile() instead, so that
|
|
* eBPF and implicitly also cBPF can get JITed!
|
|
*/
|
|
struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog)
|
|
{
|
|
return prog;
|
|
}
|
|
|
|
/* Stub for JITs that support eBPF. All cBPF code gets transformed into
|
|
* eBPF by the kernel and is later compiled by bpf_int_jit_compile().
|
|
*/
|
|
void __weak bpf_jit_compile(struct bpf_prog *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;
|
|
}
|
|
|
|
/* All definitions of tracepoints related to BPF. */
|
|
#define CREATE_TRACE_POINTS
|
|
#include <linux/bpf_trace.h>
|
|
|
|
EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_exception);
|