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

Daniel Borkmann says:

====================
pull-request: bpf-next 2022-10-03

We've added 143 non-merge commits during the last 27 day(s) which contain
a total of 151 files changed, 8321 insertions(+), 1402 deletions(-).

The main changes are:

1) Add kfuncs for PKCS#7 signature verification from BPF programs, from Roberto Sassu.

2) Add support for struct-based arguments for trampoline based BPF programs,
   from Yonghong Song.

3) Fix entry IP for kprobe-multi and trampoline probes under IBT enabled, from Jiri Olsa.

4) Batch of improvements to veristat selftest tool in particular to add CSV output,
   a comparison mode for CSV outputs and filtering, from Andrii Nakryiko.

5) Add preparatory changes needed for the BPF core for upcoming BPF HID support,
   from Benjamin Tissoires.

6) Support for direct writes to nf_conn's mark field from tc and XDP BPF program
   types, from Daniel Xu.

7) Initial batch of documentation improvements for BPF insn set spec, from Dave Thaler.

8) Add a new BPF_MAP_TYPE_USER_RINGBUF map which provides single-user-space-producer /
   single-kernel-consumer semantics for BPF ring buffer, from David Vernet.

9) Follow-up fixes to BPF allocator under RT to always use raw spinlock for the BPF
   hashtab's bucket lock, from Hou Tao.

10) Allow creating an iterator that loops through only the resources of one
    task/thread instead of all, from Kui-Feng Lee.

11) Add support for kptrs in the per-CPU arraymap, from Kumar Kartikeya Dwivedi.

12) Add a new kfunc helper for nf to set src/dst NAT IP/port in a newly allocated CT
    entry which is not yet inserted, from Lorenzo Bianconi.

13) Remove invalid recursion check for struct_ops for TCP congestion control BPF
    programs, from Martin KaFai Lau.

14) Fix W^X issue with BPF trampoline and BPF dispatcher, from Song Liu.

15) Fix percpu_counter leakage in BPF hashtab allocation error path, from Tetsuo Handa.

16) Various cleanups in BPF selftests to use preferred ASSERT_* macros, from Wang Yufen.

17) Add invocation for cgroup/connect{4,6} BPF programs for ICMP pings, from YiFei Zhu.

18) Lift blinding decision under bpf_jit_harden = 1 to bpf_capable(), from Yauheni Kaliuta.

19) Various libbpf fixes and cleanups including a libbpf NULL pointer deref, from Xin Liu.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (143 commits)
  net: netfilter: move bpf_ct_set_nat_info kfunc in nf_nat_bpf.c
  Documentation: bpf: Add implementation notes documentations to table of contents
  bpf, docs: Delete misformatted table.
  selftests/xsk: Fix double free
  bpftool: Fix error message of strerror
  libbpf: Fix overrun in netlink attribute iteration
  selftests/bpf: Fix spelling mistake "unpriviledged" -> "unprivileged"
  samples/bpf: Fix typo in xdp_router_ipv4 sample
  bpftool: Remove unused struct event_ring_info
  bpftool: Remove unused struct btf_attach_point
  bpf, docs: Add TOC and fix formatting.
  bpf, docs: Add Clang note about BPF_ALU
  bpf, docs: Move Clang notes to a separate file
  bpf, docs: Linux byteswap note
  bpf, docs: Move legacy packet instructions to a separate file
  selftests/bpf: Check -EBUSY for the recurred bpf_setsockopt(TCP_CONGESTION)
  bpf: tcp: Stop bpf_setsockopt(TCP_CONGESTION) in init ops to recur itself
  bpf: Refactor bpf_setsockopt(TCP_CONGESTION) handling into another function
  bpf: Move the "cdg" tcp-cc check to the common sol_tcp_sockopt()
  bpf: Add __bpf_prog_{enter,exit}_struct_ops for struct_ops trampoline
  ...
====================

Link: https://lore.kernel.org/r/20221003194915.11847-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 50 insertions, 56 deletions

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 3ad139285fad..184ce1684dcd 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -163,6 +163,7 @@ static const char * const map_type_name[] = {
 	[BPF_MAP_TYPE_INODE_STORAGE]		= "inode_storage",
 	[BPF_MAP_TYPE_TASK_STORAGE]		= "task_storage",
 	[BPF_MAP_TYPE_BLOOM_FILTER]		= "bloom_filter",
+	[BPF_MAP_TYPE_USER_RINGBUF]             = "user_ringbuf",
 };
 
 static const char * const prog_type_name[] = {
@@ -883,7 +884,7 @@ __u32 get_kernel_version(void)
 	__u32 major, minor, patch;
 	struct utsname info;
 
-	if (access(ubuntu_kver_file, R_OK) == 0) {
+	if (faccessat(AT_FDCWD, ubuntu_kver_file, R_OK, AT_EACCESS) == 0) {
 		FILE *f;
 
 		f = fopen(ubuntu_kver_file, "r");
@@ -2096,19 +2097,30 @@ static bool get_map_field_int(const char *map_name, const struct btf *btf,
 	return true;
 }
 
+static int pathname_concat(char *buf, size_t buf_sz, const char *path, const char *name)
+{
+	int len;
+
+	len = snprintf(buf, buf_sz, "%s/%s", path, name);
+	if (len < 0)
+		return -EINVAL;
+	if (len >= buf_sz)
+		return -ENAMETOOLONG;
+
+	return 0;
+}
+
 static int build_map_pin_path(struct bpf_map *map, const char *path)
 {
 	char buf[PATH_MAX];
-	int len;
+	int err;
 
 	if (!path)
 		path = "/sys/fs/bpf";
 
-	len = snprintf(buf, PATH_MAX, "%s/%s", path, bpf_map__name(map));
-	if (len < 0)
-		return -EINVAL;
-	else if (len >= PATH_MAX)
-		return -ENAMETOOLONG;
+	err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));
+	if (err)
+		return err;
 
 	return bpf_map__set_pin_path(map, buf);
 }
@@ -2372,6 +2384,12 @@ static size_t adjust_ringbuf_sz(size_t sz)
 	return sz;
 }
 
+static bool map_is_ringbuf(const struct bpf_map *map)
+{
+	return map->def.type == BPF_MAP_TYPE_RINGBUF ||
+	       map->def.type == BPF_MAP_TYPE_USER_RINGBUF;
+}
+
 static void fill_map_from_def(struct bpf_map *map, const struct btf_map_def *def)
 {
 	map->def.type = def->map_type;
@@ -2386,7 +2404,7 @@ static void fill_map_from_def(struct bpf_map *map, const struct btf_map_def *def
 	map->btf_value_type_id = def->value_type_id;
 
 	/* auto-adjust BPF ringbuf map max_entries to be a multiple of page size */
-	if (map->def.type == BPF_MAP_TYPE_RINGBUF)
+	if (map_is_ringbuf(map))
 		map->def.max_entries = adjust_ringbuf_sz(map->def.max_entries);
 
 	if (def->parts & MAP_DEF_MAP_TYPE)
@@ -4369,7 +4387,7 @@ int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries)
 	map->def.max_entries = max_entries;
 
 	/* auto-adjust BPF ringbuf map max_entries to be a multiple of page size */
-	if (map->def.type == BPF_MAP_TYPE_RINGBUF)
+	if (map_is_ringbuf(map))
 		map->def.max_entries = adjust_ringbuf_sz(map->def.max_entries);
 
 	return 0;
@@ -7961,17 +7979,9 @@ int bpf_object__pin_maps(struct bpf_object *obj, const char *path)
 			continue;
 
 		if (path) {
-			int len;
-
-			len = snprintf(buf, PATH_MAX, "%s/%s", path,
-				       bpf_map__name(map));
-			if (len < 0) {
-				err = -EINVAL;
-				goto err_unpin_maps;
-			} else if (len >= PATH_MAX) {
-				err = -ENAMETOOLONG;
+			err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));
+			if (err)
 				goto err_unpin_maps;
-			}
 			sanitize_pin_path(buf);
 			pin_path = buf;
 		} else if (!map->pin_path) {
@@ -8009,14 +8019,9 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
 		char buf[PATH_MAX];
 
 		if (path) {
-			int len;
-
-			len = snprintf(buf, PATH_MAX, "%s/%s", path,
-				       bpf_map__name(map));
-			if (len < 0)
-				return libbpf_err(-EINVAL);
-			else if (len >= PATH_MAX)
-				return libbpf_err(-ENAMETOOLONG);
+			err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));
+			if (err)
+				return libbpf_err(err);
 			sanitize_pin_path(buf);
 			pin_path = buf;
 		} else if (!map->pin_path) {
@@ -8034,6 +8039,7 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
 int bpf_object__pin_programs(struct bpf_object *obj, const char *path)
 {
 	struct bpf_program *prog;
+	char buf[PATH_MAX];
 	int err;
 
 	if (!obj)
@@ -8045,17 +8051,9 @@ int bpf_object__pin_programs(struct bpf_object *obj, const char *path)
 	}
 
 	bpf_object__for_each_program(prog, obj) {
-		char buf[PATH_MAX];
-		int len;
-
-		len = snprintf(buf, PATH_MAX, "%s/%s", path, prog->name);
-		if (len < 0) {
-			err = -EINVAL;
-			goto err_unpin_programs;
-		} else if (len >= PATH_MAX) {
-			err = -ENAMETOOLONG;
+		err = pathname_concat(buf, sizeof(buf), path, prog->name);
+		if (err)
 			goto err_unpin_programs;
-		}
 
 		err = bpf_program__pin(prog, buf);
 		if (err)
@@ -8066,13 +8064,7 @@ int bpf_object__pin_programs(struct bpf_object *obj, const char *path)
 
 err_unpin_programs:
 	while ((prog = bpf_object__prev_program(obj, prog))) {
-		char buf[PATH_MAX];
-		int len;
-
-		len = snprintf(buf, PATH_MAX, "%s/%s", path, prog->name);
-		if (len < 0)
-			continue;
-		else if (len >= PATH_MAX)
+		if (pathname_concat(buf, sizeof(buf), path, prog->name))
 			continue;
 
 		bpf_program__unpin(prog, buf);
@@ -8091,13 +8083,10 @@ int bpf_object__unpin_programs(struct bpf_object *obj, const char *path)
 
 	bpf_object__for_each_program(prog, obj) {
 		char buf[PATH_MAX];
-		int len;
 
-		len = snprintf(buf, PATH_MAX, "%s/%s", path, prog->name);
-		if (len < 0)
-			return libbpf_err(-EINVAL);
-		else if (len >= PATH_MAX)
-			return libbpf_err(-ENAMETOOLONG);
+		err = pathname_concat(buf, sizeof(buf), path, prog->name);
+		if (err)
+			return libbpf_err(err);
 
 		err = bpf_program__unpin(prog, buf);
 		if (err)
@@ -9084,11 +9073,15 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attac
 	int err = 0;
 
 	/* BPF program's BTF ID */
-	if (attach_prog_fd) {
+	if (prog->type == BPF_PROG_TYPE_EXT || attach_prog_fd) {
+		if (!attach_prog_fd) {
+			pr_warn("prog '%s': attach program FD is not set\n", prog->name);
+			return -EINVAL;
+		}
 		err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd);
 		if (err < 0) {
-			pr_warn("failed to find BPF program (FD %d) BTF ID for '%s': %d\n",
-				 attach_prog_fd, attach_name, err);
+			pr_warn("prog '%s': failed to find BPF program (FD %d) BTF ID for '%s': %d\n",
+				 prog->name, attach_prog_fd, attach_name, err);
 			return err;
 		}
 		*btf_obj_fd = 0;
@@ -9105,7 +9098,8 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attac
 		err = find_kernel_btf_id(prog->obj, attach_name, attach_type, btf_obj_fd, btf_type_id);
 	}
 	if (err) {
-		pr_warn("failed to find kernel BTF type ID of '%s': %d\n", attach_name, err);
+		pr_warn("prog '%s': failed to find kernel BTF type ID of '%s': %d\n",
+			prog->name, attach_name, err);
 		return err;
 	}
 	return 0;
@@ -9910,7 +9904,7 @@ static bool use_debugfs(void)
 	static int has_debugfs = -1;
 
 	if (has_debugfs < 0)
-		has_debugfs = access(DEBUGFS, F_OK) == 0;
+		has_debugfs = faccessat(AT_FDCWD, DEBUGFS, F_OK, AT_EACCESS) == 0;
 
 	return has_debugfs == 1;
 }
@@ -10727,7 +10721,7 @@ static int resolve_full_path(const char *file, char *result, size_t result_sz)
 				continue;
 			snprintf(result, result_sz, "%.*s/%s", seg_len, s, file);
 			/* ensure it has required permissions */
-			if (access(result, perm) < 0)
+			if (faccessat(AT_FDCWD, result, perm, AT_EACCESS) < 0)
 				continue;
 			pr_debug("resolved '%s' to '%s'\n", file, result);
 			return 0;