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(const void *ctx,
+ const struct bpf_insn *insn)
+ {
+ return 0;
+ }
+ #endif
+
bool bpf_prog_array_compatible(struct bpf_array *array,
const struct bpf_prog *fp)
{
strict);
}
+static int update_stack_depth(struct bpf_verifier_env *env,
+ const struct bpf_func_state *func,
+ int off)
+{
+ u16 stack = env->subprog_stack_depth[func->subprogno];
+
+ if (stack >= -off)
+ return 0;
+
+ /* update known max for given subprogram */
+ env->subprog_stack_depth[func->subprogno] = -off;
+ return 0;
+}
+
+/* starting from main bpf function walk all instructions of the function
+ * and recursively walk all callees that given function can call.
+ * Ignore jump and exit insns.
+ * Since recursion is prevented by check_cfg() this algorithm
+ * only needs a local stack of MAX_CALL_FRAMES to remember callsites
+ */
+static int check_max_stack_depth(struct bpf_verifier_env *env)
+{
+ int depth = 0, frame = 0, subprog = 0, i = 0, subprog_end;
+ struct bpf_insn *insn = env->prog->insnsi;
+ int insn_cnt = env->prog->len;
+ int ret_insn[MAX_CALL_FRAMES];
+ int ret_prog[MAX_CALL_FRAMES];
+
+process_func:
+ /* round up to 32-bytes, since this is granularity
+ * of interpreter stack size
+ */
+ depth += round_up(max_t(u32, env->subprog_stack_depth[subprog], 1), 32);
+ if (depth > MAX_BPF_STACK) {
+ verbose(env, "combined stack size of %d calls is %d. Too large\n",
+ frame + 1, depth);
+ return -EACCES;
+ }
+continue_func:
+ if (env->subprog_cnt == subprog)
+ subprog_end = insn_cnt;
+ else
+ subprog_end = env->subprog_starts[subprog];
+ for (; i < subprog_end; i++) {
+ if (insn[i].code != (BPF_JMP | BPF_CALL))
+ continue;
+ if (insn[i].src_reg != BPF_PSEUDO_CALL)
+ continue;
+ /* remember insn and function to return to */
+ ret_insn[frame] = i + 1;
+ ret_prog[frame] = subprog;
+
+ /* find the callee */
+ i = i + insn[i].imm + 1;
+ subprog = find_subprog(env, i);
+ if (subprog < 0) {
+ WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
+ i);
+ return -EFAULT;
+ }
+ subprog++;
+ frame++;
+ if (frame >= MAX_CALL_FRAMES) {
+ WARN_ONCE(1, "verifier bug. Call stack is too deep\n");
+ return -EFAULT;
+ }
+ goto process_func;
+ }
+ /* end of for() loop means the last insn of the 'subprog'
+ * was reached. Doesn't matter whether it was JA or EXIT
+ */
+ if (frame == 0)
+ return 0;
+ depth -= round_up(max_t(u32, env->subprog_stack_depth[subprog], 1), 32);
+ frame--;
+ i = ret_insn[frame];
+ subprog = ret_prog[frame];
+ goto continue_func;
+}
+
++#ifndef CONFIG_BPF_JIT_ALWAYS_ON
+static int get_callee_stack_depth(struct bpf_verifier_env *env,
+ const struct bpf_insn *insn, int idx)
+{
+ int start = idx + insn->imm + 1, subprog;
+
+ subprog = find_subprog(env, start);
+ if (subprog < 0) {
+ WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
+ start);
+ return -EFAULT;
+ }
+ subprog++;
+ return env->subprog_stack_depth[subprog];
+}
++#endif
+
/* truncate register to smaller size (in bytes)
* must be called with size < BPF_REG_SIZE
*/
return 0;
}
- if (env->prog->jit_requested)
- if (jit_subprogs(env) == 0)
+static int jit_subprogs(struct bpf_verifier_env *env)
+{
+ struct bpf_prog *prog = env->prog, **func, *tmp;
+ int i, j, subprog_start, subprog_end = 0, len, subprog;
+ struct bpf_insn *insn;
+ void *old_bpf_func;
+ int err = -ENOMEM;
+
+ if (env->subprog_cnt == 0)
+ return 0;
+
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ subprog = find_subprog(env, i + insn->imm + 1);
+ if (subprog < 0) {
+ WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
+ i + insn->imm + 1);
+ return -EFAULT;
+ }
+ /* temporarily remember subprog id inside insn instead of
+ * aux_data, since next loop will split up all insns into funcs
+ */
+ insn->off = subprog + 1;
+ /* remember original imm in case JIT fails and fallback
+ * to interpreter will be needed
+ */
+ env->insn_aux_data[i].call_imm = insn->imm;
+ /* point imm to __bpf_call_base+1 from JITs point of view */
+ insn->imm = 1;
+ }
+
+ func = kzalloc(sizeof(prog) * (env->subprog_cnt + 1), GFP_KERNEL);
+ if (!func)
+ return -ENOMEM;
+
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ subprog_start = subprog_end;
+ if (env->subprog_cnt == i)
+ subprog_end = prog->len;
+ else
+ subprog_end = env->subprog_starts[i];
+
+ len = subprog_end - subprog_start;
+ func[i] = bpf_prog_alloc(bpf_prog_size(len), GFP_USER);
+ if (!func[i])
+ goto out_free;
+ memcpy(func[i]->insnsi, &prog->insnsi[subprog_start],
+ len * sizeof(struct bpf_insn));
+ func[i]->type = prog->type;
+ func[i]->len = len;
+ if (bpf_prog_calc_tag(func[i]))
+ goto out_free;
+ func[i]->is_func = 1;
+ /* Use bpf_prog_F_tag to indicate functions in stack traces.
+ * Long term would need debug info to populate names
+ */
+ func[i]->aux->name[0] = 'F';
+ func[i]->aux->stack_depth = env->subprog_stack_depth[i];
+ func[i]->jit_requested = 1;
+ func[i] = bpf_int_jit_compile(func[i]);
+ if (!func[i]->jited) {
+ err = -ENOTSUPP;
+ goto out_free;
+ }
+ cond_resched();
+ }
+ /* at this point all bpf functions were successfully JITed
+ * now populate all bpf_calls with correct addresses and
+ * run last pass of JIT
+ */
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ insn = func[i]->insnsi;
+ for (j = 0; j < func[i]->len; j++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ subprog = insn->off;
+ insn->off = 0;
+ insn->imm = (u64 (*)(u64, u64, u64, u64, u64))
+ func[subprog]->bpf_func -
+ __bpf_call_base;
+ }
+ }
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ old_bpf_func = func[i]->bpf_func;
+ tmp = bpf_int_jit_compile(func[i]);
+ if (tmp != func[i] || func[i]->bpf_func != old_bpf_func) {
+ verbose(env, "JIT doesn't support bpf-to-bpf calls\n");
+ err = -EFAULT;
+ goto out_free;
+ }
+ cond_resched();
+ }
+
+ /* finally lock prog and jit images for all functions and
+ * populate kallsysm
+ */
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ bpf_prog_lock_ro(func[i]);
+ bpf_prog_kallsyms_add(func[i]);
+ }
+
+ /* Last step: make now unused interpreter insns from main
+ * prog consistent for later dump requests, so they can
+ * later look the same as if they were interpreted only.
+ */
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ unsigned long addr;
+
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ insn->off = env->insn_aux_data[i].call_imm;
+ subprog = find_subprog(env, i + insn->off + 1);
+ addr = (unsigned long)func[subprog + 1]->bpf_func;
+ addr &= PAGE_MASK;
+ insn->imm = (u64 (*)(u64, u64, u64, u64, u64))
+ addr - __bpf_call_base;
+ }
+
+ prog->jited = 1;
+ prog->bpf_func = func[0]->bpf_func;
+ prog->aux->func = func;
+ prog->aux->func_cnt = env->subprog_cnt + 1;
+ return 0;
+out_free:
+ for (i = 0; i <= env->subprog_cnt; i++)
+ if (func[i])
+ bpf_jit_free(func[i]);
+ kfree(func);
+ /* cleanup main prog to be interpreted */
+ prog->jit_requested = 0;
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ insn->off = 0;
+ insn->imm = env->insn_aux_data[i].call_imm;
+ }
+ return err;
+}
+
+static int fixup_call_args(struct bpf_verifier_env *env)
+{
++#ifndef CONFIG_BPF_JIT_ALWAYS_ON
+ struct bpf_prog *prog = env->prog;
+ struct bpf_insn *insn = prog->insnsi;
+ int i, depth;
++#endif
++ int err;
+
-
++ err = 0;
++ if (env->prog->jit_requested) {
++ err = jit_subprogs(env);
++ if (err == 0)
+ return 0;
- return 0;
++ }
++#ifndef CONFIG_BPF_JIT_ALWAYS_ON
+ for (i = 0; i < prog->len; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ depth = get_callee_stack_depth(env, insn, i);
+ if (depth < 0)
+ return depth;
+ bpf_patch_call_args(insn, depth);
+ }
++ err = 0;
++#endif
++ return err;
+}
+
/* fixup insn->imm field of bpf_call instructions
* and inline eligible helpers as explicit sequence of BPF instructions
*
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = REJECT,
.matches = {
- {4, "R5=pkt(id=0,off=0,r=0,imm=0)"},
+ {4, "R5_w=pkt(id=0,off=0,r=0,imm=0)"},
- /* ptr & 0x40 == either 0 or 0x40 */
- {5, "R5_w=inv(id=0,umax_value=64,var_off=(0x0; 0x40))"},
- /* ptr << 2 == unknown, (4n) */
- {7, "R5_w=inv(id=0,smax_value=9223372036854775804,umax_value=18446744073709551612,var_off=(0x0; 0xfffffffffffffffc))"},
- /* (4n) + 14 == (4n+2). We blow our bounds, because
- * the add could overflow.
- */
- {8, "R5=inv(id=0,var_off=(0x2; 0xfffffffffffffffc))"},
- /* Checked s>=0 */
- {10, "R5=inv(id=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
- /* packet pointer + nonnegative (4n+2) */
- {12, "R6_w=pkt(id=1,off=0,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
- {14, "R4=pkt(id=1,off=4,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
- /* NET_IP_ALIGN + (4n+2) == (4n), alignment is fine.
- * We checked the bounds, but it might have been able
- * to overflow if the packet pointer started in the
- * upper half of the address space.
- * So we did not get a 'range' on R6, and the access
- * attempt will fail.
- */
- {16, "R6=pkt(id=1,off=0,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
+ /* R5 bitwise operator &= on pointer prohibited */
}
},
{
projects / linux / commitdiff