Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2018-11-30

The following pull-request contains BPF updates for your *net-next* tree.

(Getting out bit earlier this time to pull in a dependency from bpf.)

The main changes are:

1) Add libbpf ABI versioning and document API naming conventions
   as well as ABI versioning process, from Andrey.

2) Add a new sk_msg_pop_data() helper for sk_msg based BPF
   programs that is used in conjunction with sk_msg_push_data()
   for adding / removing meta data to the msg data, from John.

3) Optimize convert_bpf_ld_abs() for 0 offset and fix various
   lib and testsuite build failures on 32 bit, from David.

4) Make BPF prog dump for !JIT identical to how we dump subprogs
   when JIT is in use, from Yonghong.

5) Rename btf_get_from_id() to make it more conform with libbpf
   API naming conventions, from Martin.

6) Add a missing BPF kselftest config item, from Naresh.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 48 insertions, 43 deletions

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 539e8575689f..f93ed667546f 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -411,7 +411,8 @@ static void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
 
 	/* prog->aux->name will be ignored if full btf name is available */
 	if (prog->aux->btf) {
-		type = btf_type_by_id(prog->aux->btf, prog->aux->type_id);
+		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;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 998377808102..85cbeec06e50 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1214,6 +1214,7 @@ static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
 		bpf_prog_free_id(prog, do_idr_lock);
 		bpf_prog_kallsyms_del_all(prog);
 		btf_put(prog->aux->btf);
+		kvfree(prog->aux->func_info);
 
 		call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
 	}
@@ -2219,46 +2220,28 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
 	}
 
 	if (prog->aux->btf) {
+		u32 krec_size = sizeof(struct bpf_func_info);
 		u32 ucnt, urec_size;
 
 		info.btf_id = btf_id(prog->aux->btf);
 
 		ucnt = info.func_info_cnt;
-		info.func_info_cnt = prog->aux->func_cnt ? : 1;
+		info.func_info_cnt = prog->aux->func_info_cnt;
 		urec_size = info.func_info_rec_size;
-		info.func_info_rec_size = sizeof(struct bpf_func_info);
+		info.func_info_rec_size = krec_size;
 		if (ucnt) {
 			/* expect passed-in urec_size is what the kernel expects */
 			if (urec_size != info.func_info_rec_size)
 				return -EINVAL;
 
 			if (bpf_dump_raw_ok()) {
-				struct bpf_func_info kern_finfo;
 				char __user *user_finfo;
-				u32 i, insn_offset;
 
 				user_finfo = u64_to_user_ptr(info.func_info);
-				if (prog->aux->func_cnt) {
-					ucnt = min_t(u32, info.func_info_cnt, ucnt);
-					insn_offset = 0;
-					for (i = 0; i < ucnt; i++) {
-						kern_finfo.insn_offset = insn_offset;
-						kern_finfo.type_id = prog->aux->func[i]->aux->type_id;
-						if (copy_to_user(user_finfo, &kern_finfo,
-								 sizeof(kern_finfo)))
-							return -EFAULT;
-
-						/* func[i]->len holds the prog len */
-						insn_offset += prog->aux->func[i]->len;
-						user_finfo += urec_size;
-					}
-				} else {
-					kern_finfo.insn_offset = 0;
-					kern_finfo.type_id = prog->aux->type_id;
-					if (copy_to_user(user_finfo, &kern_finfo,
-							 sizeof(kern_finfo)))
-						return -EFAULT;
-				}
+				ucnt = min_t(u32, info.func_info_cnt, ucnt);
+				if (copy_to_user(user_finfo, prog->aux->func_info,
+						 krec_size * ucnt))
+					return -EFAULT;
 			} else {
 				info.func_info_cnt = 0;
 			}
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 4ce049cd30a3..9584438fa2cc 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4650,7 +4650,7 @@ static int check_btf_func(struct bpf_prog *prog, struct bpf_verifier_env *env,
 {
 	u32 i, nfuncs, urec_size, min_size, prev_offset;
 	u32 krec_size = sizeof(struct bpf_func_info);
-	struct bpf_func_info krecord = {};
+	struct bpf_func_info *krecord = NULL;
 	const struct btf_type *type;
 	void __user *urecord;
 	struct btf *btf;
@@ -4682,6 +4682,12 @@ static int check_btf_func(struct bpf_prog *prog, struct bpf_verifier_env *env,
 	urecord = u64_to_user_ptr(attr->func_info);
 	min_size = min_t(u32, krec_size, urec_size);
 
+	krecord = kvcalloc(nfuncs, krec_size, GFP_KERNEL | __GFP_NOWARN);
+	if (!krecord) {
+		ret = -ENOMEM;
+		goto free_btf;
+	}
+
 	for (i = 0; i < nfuncs; i++) {
 		ret = bpf_check_uarg_tail_zero(urecord, krec_size, urec_size);
 		if (ret) {
@@ -4696,59 +4702,69 @@ static int check_btf_func(struct bpf_prog *prog, struct bpf_verifier_env *env,
 			goto free_btf;
 		}
 
-		if (copy_from_user(&krecord, urecord, min_size)) {
+		if (copy_from_user(&krecord[i], urecord, min_size)) {
 			ret = -EFAULT;
 			goto free_btf;
 		}
 
 		/* check insn_offset */
 		if (i == 0) {
-			if (krecord.insn_offset) {
+			if (krecord[i].insn_offset) {
 				verbose(env,
 					"nonzero insn_offset %u for the first func info record",
-					krecord.insn_offset);
+					krecord[i].insn_offset);
 				ret = -EINVAL;
 				goto free_btf;
 			}
-		} else if (krecord.insn_offset <= prev_offset) {
+		} else if (krecord[i].insn_offset <= prev_offset) {
 			verbose(env,
 				"same or smaller insn offset (%u) than previous func info record (%u)",
-				krecord.insn_offset, prev_offset);
+				krecord[i].insn_offset, prev_offset);
 			ret = -EINVAL;
 			goto free_btf;
 		}
 
-		if (env->subprog_info[i].start != krecord.insn_offset) {
+		if (env->subprog_info[i].start != krecord[i].insn_offset) {
 			verbose(env, "func_info BTF section doesn't match subprog layout in BPF program\n");
 			ret = -EINVAL;
 			goto free_btf;
 		}
 
 		/* check type_id */
-		type = btf_type_by_id(btf, krecord.type_id);
+		type = btf_type_by_id(btf, krecord[i].type_id);
 		if (!type || BTF_INFO_KIND(type->info) != BTF_KIND_FUNC) {
 			verbose(env, "invalid type id %d in func info",
-				krecord.type_id);
+				krecord[i].type_id);
 			ret = -EINVAL;
 			goto free_btf;
 		}
 
-		if (i == 0)
-			prog->aux->type_id = krecord.type_id;
-		env->subprog_info[i].type_id = krecord.type_id;
-
-		prev_offset = krecord.insn_offset;
+		prev_offset = krecord[i].insn_offset;
 		urecord += urec_size;
 	}
 
 	prog->aux->btf = btf;
+	prog->aux->func_info = krecord;
+	prog->aux->func_info_cnt = nfuncs;
 	return 0;
 
 free_btf:
 	btf_put(btf);
+	kvfree(krecord);
 	return ret;
 }
 
+static void adjust_btf_func(struct bpf_verifier_env *env)
+{
+	int i;
+
+	if (!env->prog->aux->func_info)
+		return;
+
+	for (i = 0; i < env->subprog_cnt; i++)
+		env->prog->aux->func_info[i].insn_offset = env->subprog_info[i].start;
+}
+
 /* check %cur's range satisfies %old's */
 static bool range_within(struct bpf_reg_state *old,
 			 struct bpf_reg_state *cur)
@@ -6043,15 +6059,17 @@ static int jit_subprogs(struct bpf_verifier_env *env)
 		if (bpf_prog_calc_tag(func[i]))
 			goto out_free;
 		func[i]->is_func = 1;
+		func[i]->aux->func_idx = i;
+		/* the btf and func_info will be freed only at prog->aux */
+		func[i]->aux->btf = prog->aux->btf;
+		func[i]->aux->func_info = prog->aux->func_info;
+
 		/* 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_info[i].stack_depth;
 		func[i]->jit_requested = 1;
-		/* the btf will be freed only at prog->aux */
-		func[i]->aux->btf = prog->aux->btf;
-		func[i]->aux->type_id = env->subprog_info[i].type_id;
 		func[i] = bpf_int_jit_compile(func[i]);
 		if (!func[i]->jited) {
 			err = -ENOTSUPP;
@@ -6572,6 +6590,9 @@ skip_full_check:
 		convert_pseudo_ld_imm64(env);
 	}
 
+	if (ret == 0)
+		adjust_btf_func(env);
+
 err_release_maps:
 	if (!env->prog->aux->used_maps)
 		/* if we didn't copy map pointers into bpf_prog_info, release