1 files changed, 139 insertions, 41 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 90675b987148..b39de3ae50f5 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -293,13 +293,15 @@ void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt,
 	WARN_ONCE(n >= BPF_VERIFIER_TMP_LOG_SIZE - 1,
 		  "verifier log line truncated - local buffer too short\n");
 
-	n = min(log->len_total - log->len_used - 1, n);
-	log->kbuf[n] = '\0';
-
 	if (log->level == BPF_LOG_KERNEL) {
-		pr_err("BPF:%s\n", log->kbuf);
+		bool newline = n > 0 && log->kbuf[n - 1] == '\n';
+
+		pr_err("BPF: %s%s", log->kbuf, newline ? "" : "\n");
 		return;
 	}
+
+	n = min(log->len_total - log->len_used - 1, n);
+	log->kbuf[n] = '\0';
 	if (!copy_to_user(log->ubuf + log->len_used, log->kbuf, n + 1))
 		log->len_used += n;
 	else
@@ -6101,6 +6103,27 @@ static int set_map_elem_callback_state(struct bpf_verifier_env *env,
 	return 0;
 }
 
+static int set_loop_callback_state(struct bpf_verifier_env *env,
+				   struct bpf_func_state *caller,
+				   struct bpf_func_state *callee,
+				   int insn_idx)
+{
+	/* bpf_loop(u32 nr_loops, void *callback_fn, void *callback_ctx,
+	 *	    u64 flags);
+	 * callback_fn(u32 index, void *callback_ctx);
+	 */
+	callee->regs[BPF_REG_1].type = SCALAR_VALUE;
+	callee->regs[BPF_REG_2] = caller->regs[BPF_REG_3];
+
+	/* unused */
+	__mark_reg_not_init(env, &callee->regs[BPF_REG_3]);
+	__mark_reg_not_init(env, &callee->regs[BPF_REG_4]);
+	__mark_reg_not_init(env, &callee->regs[BPF_REG_5]);
+
+	callee->in_callback_fn = true;
+	return 0;
+}
+
 static int set_timer_callback_state(struct bpf_verifier_env *env,
 				    struct bpf_func_state *caller,
 				    struct bpf_func_state *callee,
@@ -6474,13 +6497,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn
 			return err;
 	}
 
-	if (func_id == BPF_FUNC_tail_call) {
-		err = check_reference_leak(env);
-		if (err) {
-			verbose(env, "tail_call would lead to reference leak\n");
-			return err;
-		}
-	} else if (is_release_function(func_id)) {
+	if (is_release_function(func_id)) {
 		err = release_reference(env, meta.ref_obj_id);
 		if (err) {
 			verbose(env, "func %s#%d reference has not been acquired before\n",
@@ -6491,42 +6508,47 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn
 
 	regs = cur_regs(env);
 
-	/* check that flags argument in get_local_storage(map, flags) is 0,
-	 * this is required because get_local_storage() can't return an error.
-	 */
-	if (func_id == BPF_FUNC_get_local_storage &&
-	    !register_is_null(&regs[BPF_REG_2])) {
-		verbose(env, "get_local_storage() doesn't support non-zero flags\n");
-		return -EINVAL;
-	}
-
-	if (func_id == BPF_FUNC_for_each_map_elem) {
+	switch (func_id) {
+	case BPF_FUNC_tail_call:
+		err = check_reference_leak(env);
+		if (err) {
+			verbose(env, "tail_call would lead to reference leak\n");
+			return err;
+		}
+		break;
+	case BPF_FUNC_get_local_storage:
+		/* check that flags argument in get_local_storage(map, flags) is 0,
+		 * this is required because get_local_storage() can't return an error.
+		 */
+		if (!register_is_null(&regs[BPF_REG_2])) {
+			verbose(env, "get_local_storage() doesn't support non-zero flags\n");
+			return -EINVAL;
+		}
+		break;
+	case BPF_FUNC_for_each_map_elem:
 		err = __check_func_call(env, insn, insn_idx_p, meta.subprogno,
 					set_map_elem_callback_state);
-		if (err < 0)
-			return -EINVAL;
-	}
-
-	if (func_id == BPF_FUNC_timer_set_callback) {
+		break;
+	case BPF_FUNC_timer_set_callback:
 		err = __check_func_call(env, insn, insn_idx_p, meta.subprogno,
 					set_timer_callback_state);
-		if (err < 0)
-			return -EINVAL;
-	}
-
-	if (func_id == BPF_FUNC_find_vma) {
+		break;
+	case BPF_FUNC_find_vma:
 		err = __check_func_call(env, insn, insn_idx_p, meta.subprogno,
 					set_find_vma_callback_state);
-		if (err < 0)
-			return -EINVAL;
-	}
-
-	if (func_id == BPF_FUNC_snprintf) {
+		break;
+	case BPF_FUNC_snprintf:
 		err = check_bpf_snprintf_call(env, regs);
-		if (err < 0)
-			return err;
+		break;
+	case BPF_FUNC_loop:
+		err = __check_func_call(env, insn, insn_idx_p, meta.subprogno,
+					set_loop_callback_state);
+		break;
 	}
 
+	if (err)
+		return err;
+
 	/* reset caller saved regs */
 	for (i = 0; i < CALLER_SAVED_REGS; i++) {
 		mark_reg_not_init(env, regs, caller_saved[i]);
@@ -10267,6 +10289,78 @@ err_free:
 	return err;
 }
 
+#define MIN_CORE_RELO_SIZE	sizeof(struct bpf_core_relo)
+#define MAX_CORE_RELO_SIZE	MAX_FUNCINFO_REC_SIZE
+
+static int check_core_relo(struct bpf_verifier_env *env,
+			   const union bpf_attr *attr,
+			   bpfptr_t uattr)
+{
+	u32 i, nr_core_relo, ncopy, expected_size, rec_size;
+	struct bpf_core_relo core_relo = {};
+	struct bpf_prog *prog = env->prog;
+	const struct btf *btf = prog->aux->btf;
+	struct bpf_core_ctx ctx = {
+		.log = &env->log,
+		.btf = btf,
+	};
+	bpfptr_t u_core_relo;
+	int err;
+
+	nr_core_relo = attr->core_relo_cnt;
+	if (!nr_core_relo)
+		return 0;
+	if (nr_core_relo > INT_MAX / sizeof(struct bpf_core_relo))
+		return -EINVAL;
+
+	rec_size = attr->core_relo_rec_size;
+	if (rec_size < MIN_CORE_RELO_SIZE ||
+	    rec_size > MAX_CORE_RELO_SIZE ||
+	    rec_size % sizeof(u32))
+		return -EINVAL;
+
+	u_core_relo = make_bpfptr(attr->core_relos, uattr.is_kernel);
+	expected_size = sizeof(struct bpf_core_relo);
+	ncopy = min_t(u32, expected_size, rec_size);
+
+	/* Unlike func_info and line_info, copy and apply each CO-RE
+	 * relocation record one at a time.
+	 */
+	for (i = 0; i < nr_core_relo; i++) {
+		/* future proofing when sizeof(bpf_core_relo) changes */
+		err = bpf_check_uarg_tail_zero(u_core_relo, expected_size, rec_size);
+		if (err) {
+			if (err == -E2BIG) {
+				verbose(env, "nonzero tailing record in core_relo");
+				if (copy_to_bpfptr_offset(uattr,
+							  offsetof(union bpf_attr, core_relo_rec_size),
+							  &expected_size, sizeof(expected_size)))
+					err = -EFAULT;
+			}
+			break;
+		}
+
+		if (copy_from_bpfptr(&core_relo, u_core_relo, ncopy)) {
+			err = -EFAULT;
+			break;
+		}
+
+		if (core_relo.insn_off % 8 || core_relo.insn_off / 8 >= prog->len) {
+			verbose(env, "Invalid core_relo[%u].insn_off:%u prog->len:%u\n",
+				i, core_relo.insn_off, prog->len);
+			err = -EINVAL;
+			break;
+		}
+
+		err = bpf_core_apply(&ctx, &core_relo, i,
+				     &prog->insnsi[core_relo.insn_off / 8]);
+		if (err)
+			break;
+		bpfptr_add(&u_core_relo, rec_size);
+	}
+	return err;
+}
+
 static int check_btf_info(struct bpf_verifier_env *env,
 			  const union bpf_attr *attr,
 			  bpfptr_t uattr)
@@ -10297,6 +10391,10 @@ static int check_btf_info(struct bpf_verifier_env *env,
 	if (err)
 		return err;
 
+	err = check_core_relo(env, attr, uattr);
+	if (err)
+		return err;
+
 	return 0;
 }
 
@@ -13975,11 +14073,11 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr)
 		log->ubuf = (char __user *) (unsigned long) attr->log_buf;
 		log->len_total = attr->log_size;
 
-		ret = -EINVAL;
 		/* log attributes have to be sane */
-		if (log->len_total < 128 || log->len_total > UINT_MAX >> 2 ||
-		    !log->level || !log->ubuf || log->level & ~BPF_LOG_MASK)
+		if (!bpf_verifier_log_attr_valid(log)) {
+			ret = -EINVAL;
 			goto err_unlock;
+		}
 	}
 
 	if (IS_ERR(btf_vmlinux)) {