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-rw-r--r--kernel/bpf/core.c2358
1 files changed, 2358 insertions, 0 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
new file mode 100644
index 000000000..33ea6ab12
--- /dev/null
+++ b/kernel/bpf/core.c
@@ -0,0 +1,2358 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Linux Socket Filter - Kernel level socket filtering
+ *
+ * Based on the design of the Berkeley Packet Filter. The new
+ * internal format has been designed by PLUMgrid:
+ *
+ * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
+ *
+ * Authors:
+ *
+ * Jay Schulist <jschlst@samba.org>
+ * Alexei Starovoitov <ast@plumgrid.com>
+ * Daniel Borkmann <dborkman@redhat.com>
+ *
+ * Andi Kleen - Fix a few bad bugs and races.
+ * Kris Katterjohn - Added many additional checks in bpf_check_classic()
+ */
+
+#include <uapi/linux/btf.h>
+#include <linux/filter.h>
+#include <linux/skbuff.h>
+#include <linux/vmalloc.h>
+#include <linux/random.h>
+#include <linux/moduleloader.h>
+#include <linux/bpf.h>
+#include <linux/btf.h>
+#include <linux/objtool.h>
+#include <linux/rbtree_latch.h>
+#include <linux/kallsyms.h>
+#include <linux/rcupdate.h>
+#include <linux/perf_event.h>
+#include <linux/extable.h>
+#include <linux/log2.h>
+#include <linux/nospec.h>
+
+#include <asm/barrier.h>
+#include <asm/unaligned.h>
+
+/* Registers */
+#define BPF_R0 regs[BPF_REG_0]
+#define BPF_R1 regs[BPF_REG_1]
+#define BPF_R2 regs[BPF_REG_2]
+#define BPF_R3 regs[BPF_REG_3]
+#define BPF_R4 regs[BPF_REG_4]
+#define BPF_R5 regs[BPF_REG_5]
+#define BPF_R6 regs[BPF_REG_6]
+#define BPF_R7 regs[BPF_REG_7]
+#define BPF_R8 regs[BPF_REG_8]
+#define BPF_R9 regs[BPF_REG_9]
+#define BPF_R10 regs[BPF_REG_10]
+
+/* Named registers */
+#define DST regs[insn->dst_reg]
+#define SRC regs[insn->src_reg]
+#define FP regs[BPF_REG_FP]
+#define AX regs[BPF_REG_AX]
+#define ARG1 regs[BPF_REG_ARG1]
+#define CTX regs[BPF_REG_CTX]
+#define IMM insn->imm
+
+/* No hurry in this branch
+ *
+ * Exported for the bpf jit load helper.
+ */
+void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size)
+{
+ u8 *ptr = NULL;
+
+ if (k >= SKF_NET_OFF) {
+ ptr = skb_network_header(skb) + k - SKF_NET_OFF;
+ } else if (k >= SKF_LL_OFF) {
+ if (unlikely(!skb_mac_header_was_set(skb)))
+ return NULL;
+ ptr = skb_mac_header(skb) + k - SKF_LL_OFF;
+ }
+ if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb))
+ return ptr;
+
+ return NULL;
+}
+
+struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+ struct bpf_prog_aux *aux;
+ struct bpf_prog *fp;
+
+ size = round_up(size, PAGE_SIZE);
+ fp = __vmalloc(size, gfp_flags);
+ if (fp == NULL)
+ return NULL;
+
+ aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
+ if (aux == NULL) {
+ vfree(fp);
+ return NULL;
+ }
+
+ fp->pages = size / PAGE_SIZE;
+ fp->aux = aux;
+ fp->aux->prog = fp;
+ fp->jit_requested = ebpf_jit_enabled();
+
+ INIT_LIST_HEAD_RCU(&fp->aux->ksym.lnode);
+ mutex_init(&fp->aux->used_maps_mutex);
+ mutex_init(&fp->aux->dst_mutex);
+
+ return fp;
+}
+
+struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+ struct bpf_prog *prog;
+ int cpu;
+
+ prog = bpf_prog_alloc_no_stats(size, gfp_extra_flags);
+ if (!prog)
+ return NULL;
+
+ prog->aux->stats = alloc_percpu_gfp(struct bpf_prog_stats, gfp_flags);
+ if (!prog->aux->stats) {
+ kfree(prog->aux);
+ vfree(prog);
+ return NULL;
+ }
+
+ for_each_possible_cpu(cpu) {
+ struct bpf_prog_stats *pstats;
+
+ pstats = per_cpu_ptr(prog->aux->stats, cpu);
+ u64_stats_init(&pstats->syncp);
+ }
+ return prog;
+}
+EXPORT_SYMBOL_GPL(bpf_prog_alloc);
+
+int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog)
+{
+ if (!prog->aux->nr_linfo || !prog->jit_requested)
+ return 0;
+
+ prog->aux->jited_linfo = kcalloc(prog->aux->nr_linfo,
+ sizeof(*prog->aux->jited_linfo),
+ GFP_KERNEL | __GFP_NOWARN);
+ if (!prog->aux->jited_linfo)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void bpf_prog_free_jited_linfo(struct bpf_prog *prog)
+{
+ kfree(prog->aux->jited_linfo);
+ prog->aux->jited_linfo = NULL;
+}
+
+void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog)
+{
+ if (prog->aux->jited_linfo && !prog->aux->jited_linfo[0])
+ bpf_prog_free_jited_linfo(prog);
+}
+
+/* The jit engine is responsible to provide an array
+ * for insn_off to the jited_off mapping (insn_to_jit_off).
+ *
+ * The idx to this array is the insn_off. Hence, the insn_off
+ * here is relative to the prog itself instead of the main prog.
+ * This array has one entry for each xlated bpf insn.
+ *
+ * jited_off is the byte off to the last byte of the jited insn.
+ *
+ * Hence, with
+ * insn_start:
+ * The first bpf insn off of the prog. The insn off
+ * here is relative to the main prog.
+ * e.g. if prog is a subprog, insn_start > 0
+ * linfo_idx:
+ * The prog's idx to prog->aux->linfo and jited_linfo
+ *
+ * jited_linfo[linfo_idx] = prog->bpf_func
+ *
+ * For i > linfo_idx,
+ *
+ * jited_linfo[i] = prog->bpf_func +
+ * insn_to_jit_off[linfo[i].insn_off - insn_start - 1]
+ */
+void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
+ const u32 *insn_to_jit_off)
+{
+ u32 linfo_idx, insn_start, insn_end, nr_linfo, i;
+ const struct bpf_line_info *linfo;
+ void **jited_linfo;
+
+ if (!prog->aux->jited_linfo)
+ /* Userspace did not provide linfo */
+ return;
+
+ linfo_idx = prog->aux->linfo_idx;
+ linfo = &prog->aux->linfo[linfo_idx];
+ insn_start = linfo[0].insn_off;
+ insn_end = insn_start + prog->len;
+
+ jited_linfo = &prog->aux->jited_linfo[linfo_idx];
+ jited_linfo[0] = prog->bpf_func;
+
+ nr_linfo = prog->aux->nr_linfo - linfo_idx;
+
+ for (i = 1; i < nr_linfo && linfo[i].insn_off < insn_end; i++)
+ /* The verifier ensures that linfo[i].insn_off is
+ * strictly increasing
+ */
+ jited_linfo[i] = prog->bpf_func +
+ insn_to_jit_off[linfo[i].insn_off - insn_start - 1];
+}
+
+void bpf_prog_free_linfo(struct bpf_prog *prog)
+{
+ bpf_prog_free_jited_linfo(prog);
+ kvfree(prog->aux->linfo);
+}
+
+struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
+ gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+ struct bpf_prog *fp;
+ u32 pages, delta;
+ int ret;
+
+ size = round_up(size, PAGE_SIZE);
+ pages = size / PAGE_SIZE;
+ if (pages <= fp_old->pages)
+ return fp_old;
+
+ delta = pages - fp_old->pages;
+ ret = __bpf_prog_charge(fp_old->aux->user, delta);
+ if (ret)
+ return NULL;
+
+ fp = __vmalloc(size, gfp_flags);
+ if (fp == NULL) {
+ __bpf_prog_uncharge(fp_old->aux->user, delta);
+ } else {
+ memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
+ fp->pages = pages;
+ fp->aux->prog = fp;
+
+ /* We keep fp->aux from fp_old around in the new
+ * reallocated structure.
+ */
+ fp_old->aux = NULL;
+ __bpf_prog_free(fp_old);
+ }
+
+ return fp;
+}
+
+void __bpf_prog_free(struct bpf_prog *fp)
+{
+ if (fp->aux) {
+ mutex_destroy(&fp->aux->used_maps_mutex);
+ mutex_destroy(&fp->aux->dst_mutex);
+ free_percpu(fp->aux->stats);
+ kfree(fp->aux->poke_tab);
+ kfree(fp->aux);
+ }
+ vfree(fp);
+}
+
+int bpf_prog_calc_tag(struct bpf_prog *fp)
+{
+ const u32 bits_offset = SHA1_BLOCK_SIZE - sizeof(__be64);
+ u32 raw_size = bpf_prog_tag_scratch_size(fp);
+ u32 digest[SHA1_DIGEST_WORDS];
+ u32 ws[SHA1_WORKSPACE_WORDS];
+ u32 i, bsize, psize, blocks;
+ struct bpf_insn *dst;
+ bool was_ld_map;
+ u8 *raw, *todo;
+ __be32 *result;
+ __be64 *bits;
+
+ raw = vmalloc(raw_size);
+ if (!raw)
+ return -ENOMEM;
+
+ sha1_init(digest);
+ memset(ws, 0, sizeof(ws));
+
+ /* We need to take out the map fd for the digest calculation
+ * since they are unstable from user space side.
+ */
+ dst = (void *)raw;
+ for (i = 0, was_ld_map = false; i < fp->len; i++) {
+ dst[i] = fp->insnsi[i];
+ if (!was_ld_map &&
+ dst[i].code == (BPF_LD | BPF_IMM | BPF_DW) &&
+ (dst[i].src_reg == BPF_PSEUDO_MAP_FD ||
+ dst[i].src_reg == BPF_PSEUDO_MAP_VALUE)) {
+ was_ld_map = true;
+ dst[i].imm = 0;
+ } else if (was_ld_map &&
+ dst[i].code == 0 &&
+ dst[i].dst_reg == 0 &&
+ dst[i].src_reg == 0 &&
+ dst[i].off == 0) {
+ was_ld_map = false;
+ dst[i].imm = 0;
+ } else {
+ was_ld_map = false;
+ }
+ }
+
+ psize = bpf_prog_insn_size(fp);
+ memset(&raw[psize], 0, raw_size - psize);
+ raw[psize++] = 0x80;
+
+ bsize = round_up(psize, SHA1_BLOCK_SIZE);
+ blocks = bsize / SHA1_BLOCK_SIZE;
+ todo = raw;
+ if (bsize - psize >= sizeof(__be64)) {
+ bits = (__be64 *)(todo + bsize - sizeof(__be64));
+ } else {
+ bits = (__be64 *)(todo + bsize + bits_offset);
+ blocks++;
+ }
+ *bits = cpu_to_be64((psize - 1) << 3);
+
+ while (blocks--) {
+ sha1_transform(digest, todo, ws);
+ todo += SHA1_BLOCK_SIZE;
+ }
+
+ result = (__force __be32 *)digest;
+ for (i = 0; i < SHA1_DIGEST_WORDS; i++)
+ result[i] = cpu_to_be32(digest[i]);
+ memcpy(fp->tag, result, sizeof(fp->tag));
+
+ vfree(raw);
+ return 0;
+}
+
+static int bpf_adj_delta_to_imm(struct bpf_insn *insn, u32 pos, s32 end_old,
+ s32 end_new, s32 curr, const bool probe_pass)
+{
+ const s64 imm_min = S32_MIN, imm_max = S32_MAX;
+ s32 delta = end_new - end_old;
+ s64 imm = insn->imm;
+
+ if (curr < pos && curr + imm + 1 >= end_old)
+ imm += delta;
+ else if (curr >= end_new && curr + imm + 1 < end_new)
+ imm -= delta;
+ if (imm < imm_min || imm > imm_max)
+ return -ERANGE;
+ if (!probe_pass)
+ insn->imm = imm;
+ return 0;
+}
+
+static int bpf_adj_delta_to_off(struct bpf_insn *insn, u32 pos, s32 end_old,
+ s32 end_new, s32 curr, const bool probe_pass)
+{
+ const s32 off_min = S16_MIN, off_max = S16_MAX;
+ s32 delta = end_new - end_old;
+ s32 off = insn->off;
+
+ if (curr < pos && curr + off + 1 >= end_old)
+ off += delta;
+ else if (curr >= end_new && curr + off + 1 < end_new)
+ off -= delta;
+ if (off < off_min || off > off_max)
+ return -ERANGE;
+ if (!probe_pass)
+ insn->off = off;
+ return 0;
+}
+
+static int bpf_adj_branches(struct bpf_prog *prog, u32 pos, s32 end_old,
+ s32 end_new, const bool probe_pass)
+{
+ u32 i, insn_cnt = prog->len + (probe_pass ? end_new - end_old : 0);
+ struct bpf_insn *insn = prog->insnsi;
+ int ret = 0;
+
+ for (i = 0; i < insn_cnt; i++, insn++) {
+ u8 code;
+
+ /* In the probing pass we still operate on the original,
+ * unpatched image in order to check overflows before we
+ * do any other adjustments. Therefore skip the patchlet.
+ */
+ if (probe_pass && i == pos) {
+ i = end_new;
+ insn = prog->insnsi + end_old;
+ }
+ code = insn->code;
+ if ((BPF_CLASS(code) != BPF_JMP &&
+ BPF_CLASS(code) != BPF_JMP32) ||
+ BPF_OP(code) == BPF_EXIT)
+ continue;
+ /* Adjust offset of jmps if we cross patch boundaries. */
+ if (BPF_OP(code) == BPF_CALL) {
+ if (insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ ret = bpf_adj_delta_to_imm(insn, pos, end_old,
+ end_new, i, probe_pass);
+ } else {
+ ret = bpf_adj_delta_to_off(insn, pos, end_old,
+ end_new, i, probe_pass);
+ }
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static void bpf_adj_linfo(struct bpf_prog *prog, u32 off, u32 delta)
+{
+ struct bpf_line_info *linfo;
+ u32 i, nr_linfo;
+
+ nr_linfo = prog->aux->nr_linfo;
+ if (!nr_linfo || !delta)
+ return;
+
+ linfo = prog->aux->linfo;
+
+ for (i = 0; i < nr_linfo; i++)
+ if (off < linfo[i].insn_off)
+ break;
+
+ /* Push all off < linfo[i].insn_off by delta */
+ for (; i < nr_linfo; i++)
+ linfo[i].insn_off += delta;
+}
+
+struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
+ const struct bpf_insn *patch, u32 len)
+{
+ u32 insn_adj_cnt, insn_rest, insn_delta = len - 1;
+ const u32 cnt_max = S16_MAX;
+ struct bpf_prog *prog_adj;
+ int err;
+
+ /* Since our patchlet doesn't expand the image, we're done. */
+ if (insn_delta == 0) {
+ memcpy(prog->insnsi + off, patch, sizeof(*patch));
+ return prog;
+ }
+
+ insn_adj_cnt = prog->len + insn_delta;
+
+ /* Reject anything that would potentially let the insn->off
+ * target overflow when we have excessive program expansions.
+ * We need to probe here before we do any reallocation where
+ * we afterwards may not fail anymore.
+ */
+ if (insn_adj_cnt > cnt_max &&
+ (err = bpf_adj_branches(prog, off, off + 1, off + len, true)))
+ return ERR_PTR(err);
+
+ /* Several new instructions need to be inserted. Make room
+ * for them. Likely, there's no need for a new allocation as
+ * last page could have large enough tailroom.
+ */
+ prog_adj = bpf_prog_realloc(prog, bpf_prog_size(insn_adj_cnt),
+ GFP_USER);
+ if (!prog_adj)
+ return ERR_PTR(-ENOMEM);
+
+ prog_adj->len = insn_adj_cnt;
+
+ /* Patching happens in 3 steps:
+ *
+ * 1) Move over tail of insnsi from next instruction onwards,
+ * so we can patch the single target insn with one or more
+ * new ones (patching is always from 1 to n insns, n > 0).
+ * 2) Inject new instructions at the target location.
+ * 3) Adjust branch offsets if necessary.
+ */
+ insn_rest = insn_adj_cnt - off - len;
+
+ memmove(prog_adj->insnsi + off + len, prog_adj->insnsi + off + 1,
+ sizeof(*patch) * insn_rest);
+ memcpy(prog_adj->insnsi + off, patch, sizeof(*patch) * len);
+
+ /* We are guaranteed to not fail at this point, otherwise
+ * the ship has sailed to reverse to the original state. An
+ * overflow cannot happen at this point.
+ */
+ BUG_ON(bpf_adj_branches(prog_adj, off, off + 1, off + len, false));
+
+ bpf_adj_linfo(prog_adj, off, insn_delta);
+
+ return prog_adj;
+}
+
+int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt)
+{
+ /* Branch offsets can't overflow when program is shrinking, no need
+ * to call bpf_adj_branches(..., true) here
+ */
+ memmove(prog->insnsi + off, prog->insnsi + off + cnt,
+ sizeof(struct bpf_insn) * (prog->len - off - cnt));
+ prog->len -= cnt;
+
+ return WARN_ON_ONCE(bpf_adj_branches(prog, off, off + cnt, off, false));
+}
+
+static void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp)
+{
+ int i;
+
+ for (i = 0; i < fp->aux->func_cnt; i++)
+ bpf_prog_kallsyms_del(fp->aux->func[i]);
+}
+
+void bpf_prog_kallsyms_del_all(struct bpf_prog *fp)
+{
+ bpf_prog_kallsyms_del_subprogs(fp);
+ bpf_prog_kallsyms_del(fp);
+}
+
+#ifdef CONFIG_BPF_JIT
+/* All BPF JIT sysctl knobs here. */
+int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_DEFAULT_ON);
+int bpf_jit_kallsyms __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_DEFAULT_ON);
+int bpf_jit_harden __read_mostly;
+long bpf_jit_limit __read_mostly;
+long bpf_jit_limit_max __read_mostly;
+
+static void
+bpf_prog_ksym_set_addr(struct bpf_prog *prog)
+{
+ const struct bpf_binary_header *hdr = bpf_jit_binary_hdr(prog);
+ unsigned long addr = (unsigned long)hdr;
+
+ WARN_ON_ONCE(!bpf_prog_ebpf_jited(prog));
+
+ prog->aux->ksym.start = (unsigned long) prog->bpf_func;
+ prog->aux->ksym.end = addr + hdr->pages * PAGE_SIZE;
+}
+
+static void
+bpf_prog_ksym_set_name(struct bpf_prog *prog)
+{
+ char *sym = prog->aux->ksym.name;
+ const char *end = sym + KSYM_NAME_LEN;
+ const struct btf_type *type;
+ const char *func_name;
+
+ BUILD_BUG_ON(sizeof("bpf_prog_") +
+ sizeof(prog->tag) * 2 +
+ /* name has been null terminated.
+ * We should need +1 for the '_' preceding
+ * the name. However, the null character
+ * is double counted between the name and the
+ * sizeof("bpf_prog_") above, so we omit
+ * the +1 here.
+ */
+ sizeof(prog->aux->name) > KSYM_NAME_LEN);
+
+ sym += snprintf(sym, KSYM_NAME_LEN, "bpf_prog_");
+ sym = bin2hex(sym, prog->tag, sizeof(prog->tag));
+
+ /* prog->aux->name will be ignored if full btf name is available */
+ if (prog->aux->func_info_cnt) {
+ type = btf_type_by_id(prog->aux->btf,
+ prog->aux->func_info[prog->aux->func_idx].type_id);
+ func_name = btf_name_by_offset(prog->aux->btf, type->name_off);
+ snprintf(sym, (size_t)(end - sym), "_%s", func_name);
+ return;
+ }
+
+ if (prog->aux->name[0])
+ snprintf(sym, (size_t)(end - sym), "_%s", prog->aux->name);
+ else
+ *sym = 0;
+}
+
+static unsigned long bpf_get_ksym_start(struct latch_tree_node *n)
+{
+ return container_of(n, struct bpf_ksym, tnode)->start;
+}
+
+static __always_inline bool bpf_tree_less(struct latch_tree_node *a,
+ struct latch_tree_node *b)
+{
+ return bpf_get_ksym_start(a) < bpf_get_ksym_start(b);
+}
+
+static __always_inline int bpf_tree_comp(void *key, struct latch_tree_node *n)
+{
+ unsigned long val = (unsigned long)key;
+ const struct bpf_ksym *ksym;
+
+ ksym = container_of(n, struct bpf_ksym, tnode);
+
+ if (val < ksym->start)
+ return -1;
+ /* Ensure that we detect return addresses as part of the program, when
+ * the final instruction is a call for a program part of the stack
+ * trace. Therefore, do val > ksym->end instead of val >= ksym->end.
+ */
+ if (val > ksym->end)
+ return 1;
+
+ return 0;
+}
+
+static const struct latch_tree_ops bpf_tree_ops = {
+ .less = bpf_tree_less,
+ .comp = bpf_tree_comp,
+};
+
+static DEFINE_SPINLOCK(bpf_lock);
+static LIST_HEAD(bpf_kallsyms);
+static struct latch_tree_root bpf_tree __cacheline_aligned;
+
+void bpf_ksym_add(struct bpf_ksym *ksym)
+{
+ spin_lock_bh(&bpf_lock);
+ WARN_ON_ONCE(!list_empty(&ksym->lnode));
+ list_add_tail_rcu(&ksym->lnode, &bpf_kallsyms);
+ latch_tree_insert(&ksym->tnode, &bpf_tree, &bpf_tree_ops);
+ spin_unlock_bh(&bpf_lock);
+}
+
+static void __bpf_ksym_del(struct bpf_ksym *ksym)
+{
+ if (list_empty(&ksym->lnode))
+ return;
+
+ latch_tree_erase(&ksym->tnode, &bpf_tree, &bpf_tree_ops);
+ list_del_rcu(&ksym->lnode);
+}
+
+void bpf_ksym_del(struct bpf_ksym *ksym)
+{
+ spin_lock_bh(&bpf_lock);
+ __bpf_ksym_del(ksym);
+ spin_unlock_bh(&bpf_lock);
+}
+
+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) ||
+ !bpf_capable())
+ return;
+
+ bpf_prog_ksym_set_addr(fp);
+ bpf_prog_ksym_set_name(fp);
+ fp->aux->ksym.prog = true;
+
+ bpf_ksym_add(&fp->aux->ksym);
+}
+
+void bpf_prog_kallsyms_del(struct bpf_prog *fp)
+{
+ if (!bpf_prog_kallsyms_candidate(fp))
+ return;
+
+ bpf_ksym_del(&fp->aux->ksym);
+}
+
+static struct bpf_ksym *bpf_ksym_find(unsigned long addr)
+{
+ struct latch_tree_node *n;
+
+ n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops);
+ return n ? container_of(n, struct bpf_ksym, tnode) : NULL;
+}
+
+const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
+ unsigned long *off, char *sym)
+{
+ struct bpf_ksym *ksym;
+ char *ret = NULL;
+
+ rcu_read_lock();
+ ksym = bpf_ksym_find(addr);
+ if (ksym) {
+ unsigned long symbol_start = ksym->start;
+ unsigned long symbol_end = ksym->end;
+
+ strncpy(sym, ksym->name, KSYM_NAME_LEN);
+
+ 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_ksym_find(addr) != NULL;
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static struct bpf_prog *bpf_prog_ksym_find(unsigned long addr)
+{
+ struct bpf_ksym *ksym = bpf_ksym_find(addr);
+
+ return ksym && ksym->prog ?
+ container_of(ksym, struct bpf_prog_aux, ksym)->prog :
+ NULL;
+}
+
+const struct exception_table_entry *search_bpf_extables(unsigned long addr)
+{
+ const struct exception_table_entry *e = NULL;
+ struct bpf_prog *prog;
+
+ rcu_read_lock();
+ prog = bpf_prog_ksym_find(addr);
+ if (!prog)
+ goto out;
+ if (!prog->aux->num_exentries)
+ goto out;
+
+ e = search_extable(prog->aux->extable, prog->aux->num_exentries, addr);
+out:
+ rcu_read_unlock();
+ return e;
+}
+
+int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
+ char *sym)
+{
+ struct bpf_ksym *ksym;
+ unsigned int it = 0;
+ int ret = -ERANGE;
+
+ if (!bpf_jit_kallsyms_enabled())
+ return ret;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ksym, &bpf_kallsyms, lnode) {
+ if (it++ != symnum)
+ continue;
+
+ strncpy(sym, ksym->name, KSYM_NAME_LEN);
+
+ *value = ksym->start;
+ *type = BPF_SYM_ELF_TYPE;
+
+ ret = 0;
+ break;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
+int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
+ struct bpf_jit_poke_descriptor *poke)
+{
+ struct bpf_jit_poke_descriptor *tab = prog->aux->poke_tab;
+ static const u32 poke_tab_max = 1024;
+ u32 slot = prog->aux->size_poke_tab;
+ u32 size = slot + 1;
+
+ if (size > poke_tab_max)
+ return -ENOSPC;
+ if (poke->tailcall_target || poke->tailcall_target_stable ||
+ poke->tailcall_bypass || poke->adj_off || poke->bypass_addr)
+ return -EINVAL;
+
+ switch (poke->reason) {
+ case BPF_POKE_REASON_TAIL_CALL:
+ if (!poke->tail_call.map)
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ tab = krealloc(tab, size * sizeof(*poke), GFP_KERNEL);
+ if (!tab)
+ return -ENOMEM;
+
+ memcpy(&tab[slot], poke, sizeof(*poke));
+ prog->aux->size_poke_tab = size;
+ prog->aux->poke_tab = tab;
+
+ return slot;
+}
+
+static atomic_long_t bpf_jit_current;
+
+/* Can be overridden by an arch's JIT compiler if it has a custom,
+ * dedicated BPF backend memory area, or if neither of the two
+ * below apply.
+ */
+u64 __weak bpf_jit_alloc_exec_limit(void)
+{
+#if defined(MODULES_VADDR)
+ return MODULES_END - MODULES_VADDR;
+#else
+ return VMALLOC_END - VMALLOC_START;
+#endif
+}
+
+static int __init bpf_jit_charge_init(void)
+{
+ /* Only used as heuristic here to derive limit. */
+ bpf_jit_limit_max = bpf_jit_alloc_exec_limit();
+ bpf_jit_limit = min_t(u64, round_up(bpf_jit_limit_max >> 1,
+ PAGE_SIZE), LONG_MAX);
+ return 0;
+}
+pure_initcall(bpf_jit_charge_init);
+
+int bpf_jit_charge_modmem(u32 pages)
+{
+ if (atomic_long_add_return(pages, &bpf_jit_current) >
+ (bpf_jit_limit >> PAGE_SHIFT)) {
+ if (!bpf_capable()) {
+ atomic_long_sub(pages, &bpf_jit_current);
+ return -EPERM;
+ }
+ }
+
+ return 0;
+}
+
+void bpf_jit_uncharge_modmem(u32 pages)
+{
+ atomic_long_sub(pages, &bpf_jit_current);
+}
+
+void *__weak bpf_jit_alloc_exec(unsigned long size)
+{
+ return module_alloc(size);
+}
+
+void __weak bpf_jit_free_exec(void *addr)
+{
+ module_memfree(addr);
+}
+
+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;
+ u32 size, hole, start, pages;
+
+ WARN_ON_ONCE(!is_power_of_2(alignment) ||
+ alignment > BPF_IMAGE_ALIGNMENT);
+
+ /* 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);
+ pages = size / PAGE_SIZE;
+
+ if (bpf_jit_charge_modmem(pages))
+ return NULL;
+ hdr = bpf_jit_alloc_exec(size);
+ if (!hdr) {
+ bpf_jit_uncharge_modmem(pages);
+ return NULL;
+ }
+
+ /* Fill space with illegal/arch-dep instructions. */
+ bpf_fill_ill_insns(hdr, size);
+
+ hdr->pages = pages;
+ 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)
+{
+ u32 pages = hdr->pages;
+
+ bpf_jit_free_exec(hdr);
+ bpf_jit_uncharge_modmem(pages);
+}
+
+/* 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_free(hdr);
+
+ WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(fp));
+ }
+
+ bpf_prog_unlock_free(fp);
+}
+
+int bpf_jit_get_func_addr(const struct bpf_prog *prog,
+ const struct bpf_insn *insn, bool extra_pass,
+ u64 *func_addr, bool *func_addr_fixed)
+{
+ s16 off = insn->off;
+ s32 imm = insn->imm;
+ u8 *addr;
+
+ *func_addr_fixed = insn->src_reg != BPF_PSEUDO_CALL;
+ if (!*func_addr_fixed) {
+ /* Place-holder address till the last pass has collected
+ * all addresses for JITed subprograms in which case we
+ * can pick them up from prog->aux.
+ */
+ if (!extra_pass)
+ addr = NULL;
+ else if (prog->aux->func &&
+ off >= 0 && off < prog->aux->func_cnt)
+ addr = (u8 *)prog->aux->func[off]->bpf_func;
+ else
+ return -EINVAL;
+ } else {
+ /* Address of a BPF helper call. Since part of the core
+ * kernel, it's always at a fixed location. __bpf_call_base
+ * and the helper with imm relative to it are both in core
+ * kernel.
+ */
+ addr = (u8 *)__bpf_call_base + imm;
+ }
+
+ *func_addr = (unsigned long)addr;
+ return 0;
+}
+
+static int bpf_jit_blind_insn(const struct bpf_insn *from,
+ const struct bpf_insn *aux,
+ struct bpf_insn *to_buff,
+ bool emit_zext)
+{
+ 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);
+
+ /* Constraints on AX register:
+ *
+ * AX register is inaccessible from user space. It is mapped in
+ * all JITs, and used here for constant blinding rewrites. It is
+ * typically "stateless" meaning its contents are only valid within
+ * the executed instruction, but not across several instructions.
+ * There are a few exceptions however which are further detailed
+ * below.
+ *
+ * Constant blinding is only used by JITs, not in the interpreter.
+ * The interpreter uses AX in some occasions as a local temporary
+ * register e.g. in DIV or MOD instructions.
+ *
+ * In restricted circumstances, the verifier can also use the AX
+ * register for rewrites as long as they do not interfere with
+ * the above cases!
+ */
+ if (from->dst_reg == BPF_REG_AX || from->src_reg == BPF_REG_AX)
+ goto out;
+
+ 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_JMP32 | BPF_JEQ | BPF_K:
+ case BPF_JMP32 | BPF_JNE | BPF_K:
+ case BPF_JMP32 | BPF_JGT | BPF_K:
+ case BPF_JMP32 | BPF_JLT | BPF_K:
+ case BPF_JMP32 | BPF_JGE | BPF_K:
+ case BPF_JMP32 | BPF_JLE | BPF_K:
+ case BPF_JMP32 | BPF_JSGT | BPF_K:
+ case BPF_JMP32 | BPF_JSLT | BPF_K:
+ case BPF_JMP32 | BPF_JSGE | BPF_K:
+ case BPF_JMP32 | BPF_JSLE | BPF_K:
+ case BPF_JMP32 | BPF_JSET | BPF_K:
+ /* Accommodate for extra offset in case of a backjump. */
+ off = from->off;
+ if (off < 0)
+ off -= 2;
+ *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_JMP32_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);
+ if (emit_zext)
+ *to++ = BPF_ZEXT_REG(BPF_REG_AX);
+ *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);
+ 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,
+ clone->aux->verifier_zext);
+ if (!rewritten)
+ continue;
+
+ tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
+ if (IS_ERR(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 tmp;
+ }
+
+ 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, ARSH, 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, ARSH, 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), \
+ /* 32-bit Jump instructions. */ \
+ /* Register based. */ \
+ INSN_3(JMP32, JEQ, X), \
+ INSN_3(JMP32, JNE, X), \
+ INSN_3(JMP32, JGT, X), \
+ INSN_3(JMP32, JLT, X), \
+ INSN_3(JMP32, JGE, X), \
+ INSN_3(JMP32, JLE, X), \
+ INSN_3(JMP32, JSGT, X), \
+ INSN_3(JMP32, JSLT, X), \
+ INSN_3(JMP32, JSGE, X), \
+ INSN_3(JMP32, JSLE, X), \
+ INSN_3(JMP32, JSET, X), \
+ /* Immediate based. */ \
+ INSN_3(JMP32, JEQ, K), \
+ INSN_3(JMP32, JNE, K), \
+ INSN_3(JMP32, JGT, K), \
+ INSN_3(JMP32, JLT, K), \
+ INSN_3(JMP32, JGE, K), \
+ INSN_3(JMP32, JLE, K), \
+ INSN_3(JMP32, JSGT, K), \
+ INSN_3(JMP32, JSLT, K), \
+ INSN_3(JMP32, JSGE, K), \
+ INSN_3(JMP32, JSLE, K), \
+ INSN_3(JMP32, JSET, K), \
+ /* 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
+u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr)
+{
+ memset(dst, 0, size);
+ return -EFAULT;
+}
+
+/**
+ * __bpf_prog_run - run eBPF program on a given context
+ * @regs: is the array of MAX_BPF_EXT_REG eBPF pseudo-registers
+ * @insn: is the array of eBPF instructions
+ * @stack: is the eBPF storage stack
+ *
+ * Decode and execute eBPF instructions.
+ */
+static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
+{
+#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 * const jumptable[256] __annotate_jump_table = {
+ [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,
+ [BPF_ST | BPF_NOSPEC] = &&ST_NOSPEC,
+ [BPF_LDX | BPF_PROBE_MEM | BPF_B] = &&LDX_PROBE_MEM_B,
+ [BPF_LDX | BPF_PROBE_MEM | BPF_H] = &&LDX_PROBE_MEM_H,
+ [BPF_LDX | BPF_PROBE_MEM | BPF_W] = &&LDX_PROBE_MEM_W,
+ [BPF_LDX | BPF_PROBE_MEM | BPF_DW] = &&LDX_PROBE_MEM_DW,
+ };
+#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];
+
+ /* Explicitly mask the register-based shift amounts with 63 or 31
+ * to avoid undefined behavior. Normally this won't affect the
+ * generated code, for example, in case of native 64 bit archs such
+ * as x86-64 or arm64, the compiler is optimizing the AND away for
+ * the interpreter. In case of JITs, each of the JIT backends compiles
+ * the BPF shift operations to machine instructions which produce
+ * implementation-defined results in such a case; the resulting
+ * contents of the register may be arbitrary, but program behaviour
+ * as a whole remains defined. In other words, in case of JIT backends,
+ * the AND must /not/ be added to the emitted LSH/RSH/ARSH translation.
+ */
+ /* ALU (shifts) */
+#define SHT(OPCODE, OP) \
+ ALU64_##OPCODE##_X: \
+ DST = DST OP (SRC & 63); \
+ CONT; \
+ ALU_##OPCODE##_X: \
+ DST = (u32) DST OP ((u32) SRC & 31); \
+ CONT; \
+ ALU64_##OPCODE##_K: \
+ DST = DST OP IMM; \
+ CONT; \
+ ALU_##OPCODE##_K: \
+ DST = (u32) DST OP (u32) IMM; \
+ CONT;
+ /* ALU (rest) */
+#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(XOR, ^)
+ ALU(MUL, *)
+ SHT(LSH, <<)
+ SHT(RSH, >>)
+#undef SHT
+#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;
+ ALU_ARSH_X:
+ DST = (u64) (u32) (((s32) DST) >> (SRC & 31));
+ CONT;
+ ALU_ARSH_K:
+ DST = (u64) (u32) (((s32) DST) >> IMM);
+ CONT;
+ ALU64_ARSH_X:
+ (*(s64 *) &DST) >>= (SRC & 63);
+ CONT;
+ ALU64_ARSH_K:
+ (*(s64 *) &DST) >>= IMM;
+ CONT;
+ ALU64_MOD_X:
+ div64_u64_rem(DST, SRC, &AX);
+ DST = AX;
+ CONT;
+ ALU_MOD_X:
+ AX = (u32) DST;
+ DST = do_div(AX, (u32) SRC);
+ CONT;
+ ALU64_MOD_K:
+ div64_u64_rem(DST, IMM, &AX);
+ DST = AX;
+ CONT;
+ ALU_MOD_K:
+ AX = (u32) DST;
+ DST = do_div(AX, (u32) IMM);
+ CONT;
+ ALU64_DIV_X:
+ DST = div64_u64(DST, SRC);
+ CONT;
+ ALU_DIV_X:
+ AX = (u32) DST;
+ do_div(AX, (u32) SRC);
+ DST = (u32) AX;
+ CONT;
+ ALU64_DIV_K:
+ DST = div64_u64(DST, IMM);
+ CONT;
+ ALU_DIV_K:
+ AX = (u32) DST;
+ do_div(AX, (u32) IMM);
+ DST = (u32) AX;
+ 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
+ * handled 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_JA:
+ insn += insn->off;
+ CONT;
+ JMP_EXIT:
+ return BPF_R0;
+ /* JMP */
+#define COND_JMP(SIGN, OPCODE, CMP_OP) \
+ JMP_##OPCODE##_X: \
+ if ((SIGN##64) DST CMP_OP (SIGN##64) SRC) { \
+ insn += insn->off; \
+ CONT_JMP; \
+ } \
+ CONT; \
+ JMP32_##OPCODE##_X: \
+ if ((SIGN##32) DST CMP_OP (SIGN##32) SRC) { \
+ insn += insn->off; \
+ CONT_JMP; \
+ } \
+ CONT; \
+ JMP_##OPCODE##_K: \
+ if ((SIGN##64) DST CMP_OP (SIGN##64) IMM) { \
+ insn += insn->off; \
+ CONT_JMP; \
+ } \
+ CONT; \
+ JMP32_##OPCODE##_K: \
+ if ((SIGN##32) DST CMP_OP (SIGN##32) IMM) { \
+ insn += insn->off; \
+ CONT_JMP; \
+ } \
+ CONT;
+ COND_JMP(u, JEQ, ==)
+ COND_JMP(u, JNE, !=)
+ COND_JMP(u, JGT, >)
+ COND_JMP(u, JLT, <)
+ COND_JMP(u, JGE, >=)
+ COND_JMP(u, JLE, <=)
+ COND_JMP(u, JSET, &)
+ COND_JMP(s, JSGT, >)
+ COND_JMP(s, JSLT, <)
+ COND_JMP(s, JSGE, >=)
+ COND_JMP(s, JSLE, <=)
+#undef COND_JMP
+ /* ST, STX and LDX*/
+ ST_NOSPEC:
+ /* Speculation barrier for mitigating Speculative Store Bypass.
+ * In case of arm64, we rely on the firmware mitigation as
+ * controlled via the ssbd kernel parameter. Whenever the
+ * mitigation is enabled, it works for all of the kernel code
+ * with no need to provide any additional instructions here.
+ * In case of x86, we use 'lfence' insn for mitigation. We
+ * reuse preexisting logic from Spectre v1 mitigation that
+ * happens to produce the required code on x86 for v4 as well.
+ */
+ barrier_nospec();
+ CONT;
+#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; \
+ LDX_PROBE_MEM_##SIZEOP: \
+ bpf_probe_read_kernel(&DST, sizeof(SIZE), \
+ (const void *)(long) (SRC + insn->off)); \
+ DST = *((SIZE *)&DST); \
+ 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;
+}
+
+#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_EXT_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_EXT_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)
+{
+ bool ret;
+
+ if (fp->kprobe_override)
+ return false;
+
+ spin_lock(&array->aux->owner.lock);
+
+ if (!array->aux->owner.type) {
+ /* There's no owner yet where we could check for
+ * compatibility.
+ */
+ array->aux->owner.type = fp->type;
+ array->aux->owner.jited = fp->jited;
+ ret = true;
+ } else {
+ ret = array->aux->owner.type == fp->type &&
+ array->aux->owner.jited == fp->jited;
+ }
+ spin_unlock(&array->aux->owner.lock);
+ return ret;
+}
+
+static int bpf_check_tail_call(const struct bpf_prog *fp)
+{
+ struct bpf_prog_aux *aux = fp->aux;
+ int i, ret = 0;
+
+ mutex_lock(&aux->used_maps_mutex);
+ 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)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&aux->used_maps_mutex);
+ return ret;
+}
+
+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)) {
+ *err = bpf_prog_alloc_jited_linfo(fp);
+ if (*err)
+ return fp;
+
+ fp = bpf_int_jit_compile(fp);
+ if (!fp->jited) {
+ bpf_prog_free_jited_linfo(fp);
+#ifdef CONFIG_BPF_JIT_ALWAYS_ON
+ *err = -ENOTSUPP;
+ return fp;
+#endif
+ } else {
+ bpf_prog_free_unused_jited_linfo(fp);
+ }
+ } 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 *progs)
+{
+ if (!progs || progs == &empty_prog_array.hdr)
+ return;
+ kfree_rcu(progs, rcu);
+}
+
+int bpf_prog_array_length(struct bpf_prog_array *array)
+{
+ struct bpf_prog_array_item *item;
+ u32 cnt = 0;
+
+ for (item = array->items; item->prog; item++)
+ if (item->prog != &dummy_bpf_prog.prog)
+ cnt++;
+ return cnt;
+}
+
+bool bpf_prog_array_is_empty(struct bpf_prog_array *array)
+{
+ struct bpf_prog_array_item *item;
+
+ for (item = array->items; item->prog; item++)
+ if (item->prog != &dummy_bpf_prog.prog)
+ return false;
+ return true;
+}
+
+static bool bpf_prog_array_copy_core(struct bpf_prog_array *array,
+ u32 *prog_ids,
+ u32 request_cnt)
+{
+ struct bpf_prog_array_item *item;
+ int i = 0;
+
+ for (item = array->items; 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 *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.
+ */
+ ids = kcalloc(cnt, sizeof(u32), GFP_USER | __GFP_NOWARN);
+ if (!ids)
+ return -ENOMEM;
+ nospc = bpf_prog_array_copy_core(array, ids, cnt);
+ 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 *array,
+ struct bpf_prog *old_prog)
+{
+ struct bpf_prog_array_item *item;
+
+ for (item = array->items; item->prog; item++)
+ if (item->prog == old_prog) {
+ WRITE_ONCE(item->prog, &dummy_bpf_prog.prog);
+ break;
+ }
+}
+
+/**
+ * bpf_prog_array_delete_safe_at() - Replaces the program at the given
+ * index into the program array with
+ * a dummy no-op program.
+ * @array: a bpf_prog_array
+ * @index: the index of the program to replace
+ *
+ * Skips over dummy programs, by not counting them, when calculating
+ * the position of the program to replace.
+ *
+ * Return:
+ * * 0 - Success
+ * * -EINVAL - Invalid index value. Must be a non-negative integer.
+ * * -ENOENT - Index out of range
+ */
+int bpf_prog_array_delete_safe_at(struct bpf_prog_array *array, int index)
+{
+ return bpf_prog_array_update_at(array, index, &dummy_bpf_prog.prog);
+}
+
+/**
+ * bpf_prog_array_update_at() - Updates the program at the given index
+ * into the program array.
+ * @array: a bpf_prog_array
+ * @index: the index of the program to update
+ * @prog: the program to insert into the array
+ *
+ * Skips over dummy programs, by not counting them, when calculating
+ * the position of the program to update.
+ *
+ * Return:
+ * * 0 - Success
+ * * -EINVAL - Invalid index value. Must be a non-negative integer.
+ * * -ENOENT - Index out of range
+ */
+int bpf_prog_array_update_at(struct bpf_prog_array *array, int index,
+ struct bpf_prog *prog)
+{
+ struct bpf_prog_array_item *item;
+
+ if (unlikely(index < 0))
+ return -EINVAL;
+
+ for (item = array->items; item->prog; item++) {
+ if (item->prog == &dummy_bpf_prog.prog)
+ continue;
+ if (!index) {
+ WRITE_ONCE(item->prog, prog);
+ return 0;
+ }
+ index--;
+ }
+ return -ENOENT;
+}
+
+int bpf_prog_array_copy(struct bpf_prog_array *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 *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;
+}
+
+void __bpf_free_used_maps(struct bpf_prog_aux *aux,
+ struct bpf_map **used_maps, u32 len)
+{
+ struct bpf_map *map;
+ u32 i;
+
+ for (i = 0; i < len; i++) {
+ map = used_maps[i];
+ if (map->ops->map_poke_untrack)
+ map->ops->map_poke_untrack(map, aux);
+ bpf_map_put(map);
+ }
+}
+
+static void bpf_free_used_maps(struct bpf_prog_aux *aux)
+{
+ __bpf_free_used_maps(aux, aux->used_maps, aux->used_map_cnt);
+ kfree(aux->used_maps);
+}
+
+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);
+ bpf_free_used_maps(aux);
+ 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
+ if (aux->dst_trampoline)
+ bpf_trampoline_put(aux->dst_trampoline);
+ for (i = 0; i < aux->func_cnt; i++) {
+ /* We can just unlink the subprog poke descriptor table as
+ * it was originally linked to the main program and is also
+ * released along with it.
+ */
+ aux->func[i]->aux->poke_tab = NULL;
+ 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;
+
+ if (aux->dst_prog)
+ bpf_prog_put(aux->dst_prog);
+ 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;
+}
+
+BPF_CALL_0(bpf_get_raw_cpu_id)
+{
+ return raw_smp_processor_id();
+}
+
+/* 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_map_push_elem_proto __weak;
+const struct bpf_func_proto bpf_map_pop_elem_proto __weak;
+const struct bpf_func_proto bpf_map_peek_elem_proto __weak;
+const struct bpf_func_proto bpf_spin_lock_proto __weak;
+const struct bpf_func_proto bpf_spin_unlock_proto __weak;
+const struct bpf_func_proto bpf_jiffies64_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_ktime_get_boot_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_get_current_cgroup_id_proto __weak;
+const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto __weak;
+const struct bpf_func_proto bpf_get_local_storage_proto __weak;
+const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto __weak;
+const struct bpf_func_proto bpf_snprintf_btf_proto __weak;
+const struct bpf_func_proto bpf_seq_printf_btf_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;
+}
+
+/* Return TRUE if the JIT backend wants verifier to enable sub-register usage
+ * analysis code and wants explicit zero extension inserted by verifier.
+ * Otherwise, return FALSE.
+ */
+bool __weak bpf_jit_needs_zext(void)
+{
+ 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;
+}
+
+int __weak bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
+ void *addr1, void *addr2)
+{
+ return -ENOTSUPP;
+}
+
+DEFINE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
+EXPORT_SYMBOL(bpf_stats_enabled_key);
+
+/* All definitions of tracepoints related to BPF. */
+#define CREATE_TRACE_POINTS
+#include <linux/bpf_trace.h>
+
+EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_exception);
+EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_bulk_tx);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 01:11:27 +0000