Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2023-01-04

We've added 45 non-merge commits during the last 21 day(s) which contain
a total of 50 files changed, 1454 insertions(+), 375 deletions(-).

The main changes are:

1) Fixes, improvements and refactoring of parts of BPF verifier's
   state equivalence checks, from Andrii Nakryiko.

2) Fix a few corner cases in libbpf's BTF-to-C converter in particular
   around padding handling and enums, also from Andrii Nakryiko.

3) Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better
  support decap on GRE tunnel devices not operating in collect metadata,
  from Christian Ehrig.

4) Improve x86 JIT's codegen for PROBE_MEM runtime error checks,
   from Dave Marchevsky.

5) Remove the need for trace_printk_lock for bpf_trace_printk
   and bpf_trace_vprintk helpers, from Jiri Olsa.

6) Add proper documentation for BPF_MAP_TYPE_SOCK{MAP,HASH} maps,
   from Maryam Tahhan.

7) Improvements in libbpf's btf_parse_elf error handling, from Changbin Du.

8) Bigger batch of improvements to BPF tracing code samples,
   from Daniel T. Lee.

9) Add LoongArch support to libbpf's bpf_tracing helper header,
   from Hengqi Chen.

10) Fix a libbpf compiler warning in perf_event_open_probe on arm32,
    from Khem Raj.

11) Optimize bpf_local_storage_elem by removing 56 bytes of padding,
    from Martin KaFai Lau.

12) Use pkg-config to locate libelf for resolve_btfids build,
    from Shen Jiamin.

13) Various libbpf improvements around API documentation and errno
    handling, from Xin Liu.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (45 commits)
  libbpf: Return -ENODATA for missing btf section
  libbpf: Add LoongArch support to bpf_tracing.h
  libbpf: Restore errno after pr_warn.
  libbpf: Added the description of some API functions
  libbpf: Fix invalid return address register in s390
  samples/bpf: Use BPF_KSYSCALL macro in syscall tracing programs
  samples/bpf: Fix tracex2 by using BPF_KSYSCALL macro
  samples/bpf: Change _kern suffix to .bpf with syscall tracing program
  samples/bpf: Use vmlinux.h instead of implicit headers in syscall tracing program
  samples/bpf: Use kyscall instead of kprobe in syscall tracing program
  bpf: rename list_head -> graph_root in field info types
  libbpf: fix errno is overwritten after being closed.
  bpf: fix regs_exact() logic in regsafe() to remap IDs correctly
  bpf: perform byte-by-byte comparison only when necessary in regsafe()
  bpf: reject non-exact register type matches in regsafe()
  bpf: generalize MAYBE_NULL vs non-MAYBE_NULL rule
  bpf: reorganize struct bpf_reg_state fields
  bpf: teach refsafe() to take into account ID remapping
  bpf: Remove unused field initialization in bpf's ctl_table
  selftests/bpf: Add jit probe_mem corner case tests to s390x denylist
  ...
====================

Link: https://lore.kernel.org/r/20230105000926.31350-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

16 files changed, 58 insertions, 90 deletions

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 727da3c5879b2e..22039a0a5b35e7 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -125,21 +125,21 @@ always-y += sockex1_kern.o
 always-y += sockex2_kern.o
 always-y += sockex3_kern.o
 always-y += tracex1_kern.o
-always-y += tracex2_kern.o
+always-y += tracex2.bpf.o
 always-y += tracex3_kern.o
 always-y += tracex4_kern.o
 always-y += tracex5_kern.o
 always-y += tracex6_kern.o
 always-y += tracex7_kern.o
 always-y += sock_flags_kern.o
-always-y += test_probe_write_user_kern.o
-always-y += trace_output_kern.o
+always-y += test_probe_write_user.bpf.o
+always-y += trace_output.bpf.o
 always-y += tcbpf1_kern.o
 always-y += tc_l2_redirect_kern.o
 always-y += lathist_kern.o
 always-y += offwaketime_kern.o
 always-y += spintest_kern.o
-always-y += map_perf_test_kern.o
+always-y += map_perf_test.bpf.o
 always-y += test_overhead_tp_kern.o
 always-y += test_overhead_raw_tp_kern.o
 always-y += test_overhead_kprobe_kern.o
@@ -147,7 +147,7 @@ always-y += parse_varlen.o parse_simple.o parse_ldabs.o
 always-y += test_cgrp2_tc_kern.o
 always-y += xdp1_kern.o
 always-y += xdp2_kern.o
-always-y += test_current_task_under_cgroup_kern.o
+always-y += test_current_task_under_cgroup.bpf.o
 always-y += trace_event_kern.o
 always-y += sampleip_kern.o
 always-y += lwt_len_hist_kern.o
diff --git a/samples/bpf/gnu/stubs.h b/samples/bpf/gnu/stubs.h
new file mode 100644
index 00000000000000..719225b1662697
--- /dev/null
+++ b/samples/bpf/gnu/stubs.h
@@ -0,0 +1 @@
+/* dummy .h to trick /usr/include/features.h to work with 'clang -target bpf' */
diff --git a/samples/bpf/map_perf_test_kern.c b/samples/bpf/map_perf_test.bpf.c
index 7342c5b2f27873..3cdeba2afe12d5 100644
--- a/samples/bpf/map_perf_test_kern.c
+++ b/samples/bpf/map_perf_test.bpf.c
@@ -4,14 +4,12 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
-#include <linux/skbuff.h>
-#include <linux/netdevice.h>
+#include "vmlinux.h"
+#include <errno.h>
 #include <linux/version.h>
-#include <uapi/linux/bpf.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 #include <bpf/bpf_core_read.h>
-#include "trace_common.h"
 
 #define MAX_ENTRIES 1000
 #define MAX_NR_CPUS 1024
@@ -102,8 +100,8 @@ struct {
 	__uint(max_entries, MAX_ENTRIES);
 } lru_hash_lookup_map SEC(".maps");
 
-SEC("kprobe/" SYSCALL(sys_getuid))
-int stress_hmap(struct pt_regs *ctx)
+SEC("ksyscall/getuid")
+int BPF_KSYSCALL(stress_hmap)
 {
 	u32 key = bpf_get_current_pid_tgid();
 	long init_val = 1;
@@ -120,8 +118,8 @@ int stress_hmap(struct pt_regs *ctx)
 	return 0;
 }
 
-SEC("kprobe/" SYSCALL(sys_geteuid))
-int stress_percpu_hmap(struct pt_regs *ctx)
+SEC("ksyscall/geteuid")
+int BPF_KSYSCALL(stress_percpu_hmap)
 {
 	u32 key = bpf_get_current_pid_tgid();
 	long init_val = 1;
@@ -137,8 +135,8 @@ int stress_percpu_hmap(struct pt_regs *ctx)
 	return 0;
 }
 
-SEC("kprobe/" SYSCALL(sys_getgid))
-int stress_hmap_alloc(struct pt_regs *ctx)
+SEC("ksyscall/getgid")
+int BPF_KSYSCALL(stress_hmap_alloc)
 {
 	u32 key = bpf_get_current_pid_tgid();
 	long init_val = 1;
@@ -154,8 +152,8 @@ int stress_hmap_alloc(struct pt_regs *ctx)
 	return 0;
 }
 
-SEC("kprobe/" SYSCALL(sys_getegid))
-int stress_percpu_hmap_alloc(struct pt_regs *ctx)
+SEC("ksyscall/getegid")
+int BPF_KSYSCALL(stress_percpu_hmap_alloc)
 {
 	u32 key = bpf_get_current_pid_tgid();
 	long init_val = 1;
@@ -170,11 +168,10 @@ int stress_percpu_hmap_alloc(struct pt_regs *ctx)
 	}
 	return 0;
 }
-
-SEC("kprobe/" SYSCALL(sys_connect))
-int stress_lru_hmap_alloc(struct pt_regs *ctx)
+SEC("ksyscall/connect")
+int BPF_KSYSCALL(stress_lru_hmap_alloc, int fd, struct sockaddr_in *uservaddr,
+		 int addrlen)
 {
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1_CORE(ctx);
 	char fmt[] = "Failed at stress_lru_hmap_alloc. ret:%dn";
 	union {
 		u16 dst6[8];
@@ -187,14 +184,11 @@ int stress_lru_hmap_alloc(struct pt_regs *ctx)
 			u32 key;
 		};
 	} test_params;
-	struct sockaddr_in6 *in6;
+	struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)uservaddr;
 	u16 test_case;
-	int addrlen, ret;
 	long val = 1;
 	u32 key = 0;
-
-	in6 = (struct sockaddr_in6 *)PT_REGS_PARM2_CORE(real_regs);
-	addrlen = (int)PT_REGS_PARM3_CORE(real_regs);
+	int ret;
 
 	if (addrlen != sizeof(*in6))
 		return 0;
@@ -251,8 +245,8 @@ done:
 	return 0;
 }
 
-SEC("kprobe/" SYSCALL(sys_gettid))
-int stress_lpm_trie_map_alloc(struct pt_regs *ctx)
+SEC("ksyscall/gettid")
+int BPF_KSYSCALL(stress_lpm_trie_map_alloc)
 {
 	union {
 		u32 b32[2];
@@ -273,8 +267,8 @@ int stress_lpm_trie_map_alloc(struct pt_regs *ctx)
 	return 0;
 }
 
-SEC("kprobe/" SYSCALL(sys_getpgid))
-int stress_hash_map_lookup(struct pt_regs *ctx)
+SEC("ksyscall/getpgid")
+int BPF_KSYSCALL(stress_hash_map_lookup)
 {
 	u32 key = 1, i;
 	long *value;
@@ -286,8 +280,8 @@ int stress_hash_map_lookup(struct pt_regs *ctx)
 	return 0;
 }
 
-SEC("kprobe/" SYSCALL(sys_getppid))
-int stress_array_map_lookup(struct pt_regs *ctx)
+SEC("ksyscall/getppid")
+int BPF_KSYSCALL(stress_array_map_lookup)
 {
 	u32 key = 1, i;
 	long *value;
diff --git a/samples/bpf/map_perf_test_user.c b/samples/bpf/map_perf_test_user.c
index 1bb53f4b29e11e..d2fbcf963cdf6d 100644
--- a/samples/bpf/map_perf_test_user.c
+++ b/samples/bpf/map_perf_test_user.c
@@ -443,7 +443,7 @@ int main(int argc, char **argv)
 	if (argc > 4)
 		max_cnt = atoi(argv[4]);
 
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
diff --git a/samples/bpf/test_current_task_under_cgroup_kern.c b/samples/bpf/test_current_task_under_cgroup.bpf.c
index fbd43e2bb4d3ed..58b9cf7ed659ab 100644
--- a/samples/bpf/test_current_task_under_cgroup_kern.c
+++ b/samples/bpf/test_current_task_under_cgroup.bpf.c
@@ -5,12 +5,11 @@
  * License as published by the Free Software Foundation.
  */
 
-#include <linux/ptrace.h>
-#include <uapi/linux/bpf.h>
+#include "vmlinux.h"
 #include <linux/version.h>
 #include <bpf/bpf_helpers.h>
-#include <uapi/linux/utsname.h>
-#include "trace_common.h"
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
 
 struct {
 	__uint(type, BPF_MAP_TYPE_CGROUP_ARRAY);
@@ -27,8 +26,8 @@ struct {
 } perf_map SEC(".maps");
 
 /* Writes the last PID that called sync to a map at index 0 */
-SEC("kprobe/" SYSCALL(sys_sync))
-int bpf_prog1(struct pt_regs *ctx)
+SEC("ksyscall/sync")
+int BPF_KSYSCALL(bpf_prog1)
 {
 	u64 pid = bpf_get_current_pid_tgid();
 	int idx = 0;
diff --git a/samples/bpf/test_current_task_under_cgroup_user.c b/samples/bpf/test_current_task_under_cgroup_user.c
index ac251a417f45fa..9726ed2a8a8bf5 100644
--- a/samples/bpf/test_current_task_under_cgroup_user.c
+++ b/samples/bpf/test_current_task_under_cgroup_user.c
@@ -14,14 +14,14 @@
 int main(int argc, char **argv)
 {
 	pid_t remote_pid, local_pid = getpid();
+	int cg2 = -1, idx = 0, rc = 1;
 	struct bpf_link *link = NULL;
 	struct bpf_program *prog;
-	int cg2, idx = 0, rc = 1;
 	struct bpf_object *obj;
 	char filename[256];
 	int map_fd[2];
 
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
@@ -103,7 +103,9 @@ int main(int argc, char **argv)
 	rc = 0;
 
 err:
-	close(cg2);
+	if (cg2 != -1)
+		close(cg2);
+
 	cleanup_cgroup_environment();
 
 cleanup:
diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index 5efb91763d6516..1c161276d57b66 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -42,11 +42,6 @@ static inline void INIT_LIST_HEAD(struct list_head *list)
 	list->prev = list;
 }
 
-static inline int list_empty(const struct list_head *head)
-{
-	return head->next == head;
-}
-
 static inline void __list_add(struct list_head *new,
 			      struct list_head *prev,
 			      struct list_head *next)
diff --git a/samples/bpf/test_map_in_map_kern.c b/samples/bpf/test_map_in_map_kern.c
index b0200c8eac09af..0e17f9ade5c569 100644
--- a/samples/bpf/test_map_in_map_kern.c
+++ b/samples/bpf/test_map_in_map_kern.c
@@ -13,7 +13,6 @@
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 #include <bpf/bpf_core_read.h>
-#include "trace_common.h"
 
 #define MAX_NR_PORTS 65536
 
diff --git a/samples/bpf/test_probe_write_user_kern.c b/samples/bpf/test_probe_write_user.bpf.c
index 220a96438d75f3..a4f3798b7fb0c0 100644
--- a/samples/bpf/test_probe_write_user_kern.c
+++ b/samples/bpf/test_probe_write_user.bpf.c
@@ -4,14 +4,12 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
-#include <linux/skbuff.h>
-#include <linux/netdevice.h>
-#include <uapi/linux/bpf.h>
+#include "vmlinux.h"
+#include <string.h>
 #include <linux/version.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 #include <bpf/bpf_core_read.h>
-#include "trace_common.h"
 
 struct {
 	__uint(type, BPF_MAP_TYPE_HASH);
@@ -28,25 +26,23 @@ struct {
  * This example sits on a syscall, and the syscall ABI is relatively stable
  * of course, across platforms, and over time, the ABI may change.
  */
-SEC("kprobe/" SYSCALL(sys_connect))
-int bpf_prog1(struct pt_regs *ctx)
+SEC("ksyscall/connect")
+int BPF_KSYSCALL(bpf_prog1, int fd, struct sockaddr_in *uservaddr,
+		 int addrlen)
 {
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1_CORE(ctx);
-	void *sockaddr_arg = (void *)PT_REGS_PARM2_CORE(real_regs);
-	int sockaddr_len = (int)PT_REGS_PARM3_CORE(real_regs);
 	struct sockaddr_in new_addr, orig_addr = {};
 	struct sockaddr_in *mapped_addr;
 
-	if (sockaddr_len > sizeof(orig_addr))
+	if (addrlen > sizeof(orig_addr))
 		return 0;
 
-	if (bpf_probe_read_user(&orig_addr, sizeof(orig_addr), sockaddr_arg) != 0)
+	if (bpf_probe_read_user(&orig_addr, sizeof(orig_addr), uservaddr) != 0)
 		return 0;
 
 	mapped_addr = bpf_map_lookup_elem(&dnat_map, &orig_addr);
 	if (mapped_addr != NULL) {
 		memcpy(&new_addr, mapped_addr, sizeof(new_addr));
-		bpf_probe_write_user(sockaddr_arg, &new_addr,
+		bpf_probe_write_user(uservaddr, &new_addr,
 				     sizeof(new_addr));
 	}
 	return 0;
diff --git a/samples/bpf/test_probe_write_user_user.c b/samples/bpf/test_probe_write_user_user.c
index 00ccfb834e4567..2a539aec411630 100644
--- a/samples/bpf/test_probe_write_user_user.c
+++ b/samples/bpf/test_probe_write_user_user.c
@@ -24,7 +24,7 @@ int main(int ac, char **argv)
 	mapped_addr_in = (struct sockaddr_in *)&mapped_addr;
 	tmp_addr_in = (struct sockaddr_in *)&tmp_addr;
 
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
diff --git a/samples/bpf/trace_common.h b/samples/bpf/trace_common.h
deleted file mode 100644
index 8cb5400aed1fc3..00000000000000
--- a/samples/bpf/trace_common.h
+++ /dev/null
@@ -1,13 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#ifndef __TRACE_COMMON_H
-#define __TRACE_COMMON_H
-
-#ifdef __x86_64__
-#define SYSCALL(SYS) "__x64_" __stringify(SYS)
-#elif defined(__s390x__)
-#define SYSCALL(SYS) "__s390x_" __stringify(SYS)
-#else
-#define SYSCALL(SYS)  __stringify(SYS)
-#endif
-
-#endif
diff --git a/samples/bpf/trace_output_kern.c b/samples/bpf/trace_output.bpf.c
index b64815af0943bb..565a73b51b04a0 100644
--- a/samples/bpf/trace_output_kern.c
+++ b/samples/bpf/trace_output.bpf.c
@@ -1,8 +1,6 @@
-#include <linux/ptrace.h>
+#include "vmlinux.h"
 #include <linux/version.h>
-#include <uapi/linux/bpf.h>
 #include <bpf/bpf_helpers.h>
-#include "trace_common.h"
 
 struct {
 	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
@@ -11,7 +9,7 @@ struct {
 	__uint(max_entries, 2);
 } my_map SEC(".maps");
 
-SEC("kprobe/" SYSCALL(sys_write))
+SEC("ksyscall/write")
 int bpf_prog1(struct pt_regs *ctx)
 {
 	struct S {
diff --git a/samples/bpf/trace_output_user.c b/samples/bpf/trace_output_user.c
index 371732f9cf8ee0..d316fd2c8e2456 100644
--- a/samples/bpf/trace_output_user.c
+++ b/samples/bpf/trace_output_user.c
@@ -51,7 +51,7 @@ int main(int argc, char **argv)
 	char filename[256];
 	FILE *f;
 
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
diff --git a/samples/bpf/tracex2_kern.c b/samples/bpf/tracex2.bpf.c
index 93e0b7680b4f03..0a5c75b367bee6 100644
--- a/samples/bpf/tracex2_kern.c
+++ b/samples/bpf/tracex2.bpf.c
@@ -4,13 +4,11 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
-#include <linux/skbuff.h>
-#include <linux/netdevice.h>
+#include "vmlinux.h"
 #include <linux/version.h>
-#include <uapi/linux/bpf.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
-#include "trace_common.h"
+#include <bpf/bpf_core_read.h>
 
 struct {
 	__uint(type, BPF_MAP_TYPE_HASH);
@@ -78,15 +76,14 @@ struct {
 	__uint(max_entries, 1024);
 } my_hist_map SEC(".maps");
 
-SEC("kprobe/" SYSCALL(sys_write))
-int bpf_prog3(struct pt_regs *ctx)
+SEC("ksyscall/write")
+int BPF_KSYSCALL(bpf_prog3, unsigned int fd, const char *buf, size_t count)
 {
-	long write_size = PT_REGS_PARM3(ctx);
 	long init_val = 1;
 	long *value;
 	struct hist_key key;
 
-	key.index = log2l(write_size);
+	key.index = log2l(count);
 	key.pid_tgid = bpf_get_current_pid_tgid();
 	key.uid_gid = bpf_get_current_uid_gid();
 	bpf_get_current_comm(&key.comm, sizeof(key.comm));
diff --git a/samples/bpf/tracex2_user.c b/samples/bpf/tracex2_user.c
index 089e408abd7ad5..2131f1648cf16d 100644
--- a/samples/bpf/tracex2_user.c
+++ b/samples/bpf/tracex2_user.c
@@ -123,7 +123,7 @@ int main(int ac, char **argv)
 	int i, j = 0;
 	FILE *f;
 
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
diff --git a/samples/bpf/tracex4_user.c b/samples/bpf/tracex4_user.c
index 227b05a0bc8833..dee8f0a091ba6a 100644
--- a/samples/bpf/tracex4_user.c
+++ b/samples/bpf/tracex4_user.c
@@ -51,7 +51,7 @@ int main(int ac, char **argv)
 	struct bpf_program *prog;
 	struct bpf_object *obj;
 	char filename[256];
-	int map_fd, i, j = 0;
+	int map_fd, j = 0;
 
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
@@ -82,7 +82,7 @@ int main(int ac, char **argv)
 		j++;
 	}
 
-	for (i = 0; ; i++) {
+	while (1) {
 		print_old_objects(map_fd);
 		sleep(1);
 	}