Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of easy overlapping changes in the confict resolutions here. Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
@@ -157,7 +157,29 @@ struct bpf_verifier_stack_elem {
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#define BPF_COMPLEXITY_LIMIT_INSNS 131072
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#define BPF_COMPLEXITY_LIMIT_STACK 1024
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#define BPF_MAP_PTR_POISON ((void *)0xeB9F + POISON_POINTER_DELTA)
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#define BPF_MAP_PTR_UNPRIV 1UL
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#define BPF_MAP_PTR_POISON ((void *)((0xeB9FUL << 1) + \
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POISON_POINTER_DELTA))
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#define BPF_MAP_PTR(X) ((struct bpf_map *)((X) & ~BPF_MAP_PTR_UNPRIV))
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static bool bpf_map_ptr_poisoned(const struct bpf_insn_aux_data *aux)
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{
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return BPF_MAP_PTR(aux->map_state) == BPF_MAP_PTR_POISON;
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}
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static bool bpf_map_ptr_unpriv(const struct bpf_insn_aux_data *aux)
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{
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return aux->map_state & BPF_MAP_PTR_UNPRIV;
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}
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static void bpf_map_ptr_store(struct bpf_insn_aux_data *aux,
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const struct bpf_map *map, bool unpriv)
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{
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BUILD_BUG_ON((unsigned long)BPF_MAP_PTR_POISON & BPF_MAP_PTR_UNPRIV);
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unpriv |= bpf_map_ptr_unpriv(aux);
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aux->map_state = (unsigned long)map |
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(unpriv ? BPF_MAP_PTR_UNPRIV : 0UL);
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}
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struct bpf_call_arg_meta {
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struct bpf_map *map_ptr;
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@@ -989,7 +1011,7 @@ static bool register_is_null(struct bpf_reg_state *reg)
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*/
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static int check_stack_write(struct bpf_verifier_env *env,
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struct bpf_func_state *state, /* func where register points to */
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int off, int size, int value_regno)
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int off, int size, int value_regno, int insn_idx)
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{
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struct bpf_func_state *cur; /* state of the current function */
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int i, slot = -off - 1, spi = slot / BPF_REG_SIZE, err;
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@@ -1028,8 +1050,33 @@ static int check_stack_write(struct bpf_verifier_env *env,
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state->stack[spi].spilled_ptr = cur->regs[value_regno];
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state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN;
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for (i = 0; i < BPF_REG_SIZE; i++)
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for (i = 0; i < BPF_REG_SIZE; i++) {
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if (state->stack[spi].slot_type[i] == STACK_MISC &&
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!env->allow_ptr_leaks) {
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int *poff = &env->insn_aux_data[insn_idx].sanitize_stack_off;
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int soff = (-spi - 1) * BPF_REG_SIZE;
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/* detected reuse of integer stack slot with a pointer
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* which means either llvm is reusing stack slot or
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* an attacker is trying to exploit CVE-2018-3639
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* (speculative store bypass)
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* Have to sanitize that slot with preemptive
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* store of zero.
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*/
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if (*poff && *poff != soff) {
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/* disallow programs where single insn stores
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* into two different stack slots, since verifier
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* cannot sanitize them
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*/
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verbose(env,
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"insn %d cannot access two stack slots fp%d and fp%d",
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insn_idx, *poff, soff);
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return -EINVAL;
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}
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*poff = soff;
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}
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state->stack[spi].slot_type[i] = STACK_SPILL;
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}
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} else {
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u8 type = STACK_MISC;
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@@ -1701,7 +1748,7 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
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if (t == BPF_WRITE)
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err = check_stack_write(env, state, off, size,
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value_regno);
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value_regno, insn_idx);
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else
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err = check_stack_read(env, state, off, size,
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value_regno);
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@@ -2367,6 +2414,29 @@ static void do_refine_retval_range(struct bpf_reg_state *regs, int ret_type,
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__reg_bound_offset(ret_reg);
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}
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static int
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record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
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int func_id, int insn_idx)
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{
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struct bpf_insn_aux_data *aux = &env->insn_aux_data[insn_idx];
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if (func_id != BPF_FUNC_tail_call &&
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func_id != BPF_FUNC_map_lookup_elem)
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return 0;
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if (meta->map_ptr == NULL) {
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verbose(env, "kernel subsystem misconfigured verifier\n");
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return -EINVAL;
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}
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if (!BPF_MAP_PTR(aux->map_state))
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bpf_map_ptr_store(aux, meta->map_ptr,
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meta->map_ptr->unpriv_array);
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else if (BPF_MAP_PTR(aux->map_state) != meta->map_ptr)
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bpf_map_ptr_store(aux, BPF_MAP_PTR_POISON,
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meta->map_ptr->unpriv_array);
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return 0;
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}
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static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
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{
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const struct bpf_func_proto *fn = NULL;
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@@ -2421,13 +2491,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
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err = check_func_arg(env, BPF_REG_2, fn->arg2_type, &meta);
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if (err)
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return err;
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if (func_id == BPF_FUNC_tail_call) {
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if (meta.map_ptr == NULL) {
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verbose(env, "verifier bug\n");
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return -EINVAL;
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}
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env->insn_aux_data[insn_idx].map_ptr = meta.map_ptr;
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}
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err = check_func_arg(env, BPF_REG_3, fn->arg3_type, &meta);
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if (err)
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return err;
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@@ -2438,6 +2501,10 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
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if (err)
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return err;
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err = record_func_map(env, &meta, func_id, insn_idx);
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if (err)
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return err;
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/* Mark slots with STACK_MISC in case of raw mode, stack offset
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* is inferred from register state.
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*/
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@@ -2462,8 +2529,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
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} else if (fn->ret_type == RET_VOID) {
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regs[BPF_REG_0].type = NOT_INIT;
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} else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL) {
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struct bpf_insn_aux_data *insn_aux;
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regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
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/* There is no offset yet applied, variable or fixed */
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mark_reg_known_zero(env, regs, BPF_REG_0);
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@@ -2479,11 +2544,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
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}
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regs[BPF_REG_0].map_ptr = meta.map_ptr;
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regs[BPF_REG_0].id = ++env->id_gen;
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insn_aux = &env->insn_aux_data[insn_idx];
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if (!insn_aux->map_ptr)
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insn_aux->map_ptr = meta.map_ptr;
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else if (insn_aux->map_ptr != meta.map_ptr)
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insn_aux->map_ptr = BPF_MAP_PTR_POISON;
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} else {
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verbose(env, "unknown return type %d of func %s#%d\n",
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fn->ret_type, func_id_name(func_id), func_id);
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@@ -5245,6 +5305,34 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
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else
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continue;
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if (type == BPF_WRITE &&
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env->insn_aux_data[i + delta].sanitize_stack_off) {
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struct bpf_insn patch[] = {
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/* Sanitize suspicious stack slot with zero.
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* There are no memory dependencies for this store,
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* since it's only using frame pointer and immediate
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* constant of zero
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*/
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BPF_ST_MEM(BPF_DW, BPF_REG_FP,
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env->insn_aux_data[i + delta].sanitize_stack_off,
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0),
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/* the original STX instruction will immediately
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* overwrite the same stack slot with appropriate value
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*/
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*insn,
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};
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cnt = ARRAY_SIZE(patch);
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new_prog = bpf_patch_insn_data(env, i + delta, patch, cnt);
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if (!new_prog)
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return -ENOMEM;
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delta += cnt - 1;
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env->prog = new_prog;
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insn = new_prog->insnsi + i + delta;
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continue;
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}
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if (env->insn_aux_data[i + delta].ptr_type != PTR_TO_CTX)
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continue;
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@@ -5498,6 +5586,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
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struct bpf_insn *insn = prog->insnsi;
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const struct bpf_func_proto *fn;
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const int insn_cnt = prog->len;
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struct bpf_insn_aux_data *aux;
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struct bpf_insn insn_buf[16];
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struct bpf_prog *new_prog;
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struct bpf_map *map_ptr;
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@@ -5591,19 +5680,22 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
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insn->imm = 0;
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insn->code = BPF_JMP | BPF_TAIL_CALL;
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aux = &env->insn_aux_data[i + delta];
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if (!bpf_map_ptr_unpriv(aux))
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continue;
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/* instead of changing every JIT dealing with tail_call
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* emit two extra insns:
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* if (index >= max_entries) goto out;
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* index &= array->index_mask;
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* to avoid out-of-bounds cpu speculation
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*/
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map_ptr = env->insn_aux_data[i + delta].map_ptr;
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if (map_ptr == BPF_MAP_PTR_POISON) {
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if (bpf_map_ptr_poisoned(aux)) {
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verbose(env, "tail_call abusing map_ptr\n");
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return -EINVAL;
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}
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if (!map_ptr->unpriv_array)
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continue;
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map_ptr = BPF_MAP_PTR(aux->map_state);
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insn_buf[0] = BPF_JMP_IMM(BPF_JGE, BPF_REG_3,
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map_ptr->max_entries, 2);
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insn_buf[1] = BPF_ALU32_IMM(BPF_AND, BPF_REG_3,
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@@ -5627,9 +5719,12 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
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*/
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if (prog->jit_requested && BITS_PER_LONG == 64 &&
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insn->imm == BPF_FUNC_map_lookup_elem) {
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map_ptr = env->insn_aux_data[i + delta].map_ptr;
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if (map_ptr == BPF_MAP_PTR_POISON ||
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!map_ptr->ops->map_gen_lookup)
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aux = &env->insn_aux_data[i + delta];
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if (bpf_map_ptr_poisoned(aux))
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goto patch_call_imm;
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map_ptr = BPF_MAP_PTR(aux->map_state);
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if (!map_ptr->ops->map_gen_lookup)
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goto patch_call_imm;
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cnt = map_ptr->ops->map_gen_lookup(map_ptr, insn_buf);
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