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

Daniel Borkmann says:

====================
pull-request: bpf 2017-12-02

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

The main changes are:

1) Fix a compilation warning in xdp redirect tracepoint due to
   missing bpf.h include that pulls in struct bpf_map, from Xie.

2) Limit the maximum number of attachable BPF progs for a given
   perf event as long as uabi is not frozen yet. The hard upper
   limit is now 64 and therefore the same as with BPF multi-prog
   for cgroups. Also add related error checking for the sample
   BPF loader when enabling and attaching to the perf event, from
   Yonghong.

3) Specifically set the RLIMIT_MEMLOCK for the test_verifier_log
   case, so that the test case can always pass and not fail in
   some environments due to too low default limit, also from
   Yonghong.

4) Fix up a missing license header comment for kernel/bpf/offload.c,
   from Jakub.

5) Several fixes for bpftool, among others a crash on incorrect
   arguments when json output is used, error message handling
   fixes on unknown options and proper destruction of json writer
   for some exit cases, all from Quentin.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/trace/events/xdp.h

@@ -8,6 +8,7 @@
 #include <linux/netdevice.h>
 #include <linux/filter.h>
 #include <linux/tracepoint.h>
+#include <linux/bpf.h>
 
 #define __XDP_ACT_MAP(FN)	\
 	FN(ABORTED)		\

kernel/bpf/core.c

@@ -1447,7 +1447,8 @@ int bpf_prog_array_length(struct bpf_prog_array __rcu *progs)
 	rcu_read_lock();
 	prog = rcu_dereference(progs)->progs;
 	for (; *prog; prog++)
-		cnt++;
+		if (*prog != &dummy_bpf_prog.prog)
+			cnt++;
 	rcu_read_unlock();
 	return cnt;
 }

kernel/bpf/offload.c

+/*
+ * Copyright (C) 2017 Netronome Systems, Inc.
+ *
+ * This software is licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree.
+ *
+ * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
+ * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
+ * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
+ * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+ */
+
 #include <linux/bpf.h>
 #include <linux/bpf_verifier.h>
 #include <linux/bug.h>

kernel/trace/bpf_trace.c

@@ -759,6 +759,8 @@ const struct bpf_prog_ops perf_event_prog_ops = {
 
 static DEFINE_MUTEX(bpf_event_mutex);
 
+#define BPF_TRACE_MAX_PROGS 64
+
 int perf_event_attach_bpf_prog(struct perf_event *event,
 			       struct bpf_prog *prog)
 {
@@ -772,6 +774,12 @@ int perf_event_attach_bpf_prog(struct perf_event *event,
 		goto unlock;
 
 	old_array = event->tp_event->prog_array;
+	if (old_array &&
+	    bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
+		ret = -E2BIG;
+		goto unlock;
+	}
+
 	ret = bpf_prog_array_copy(old_array, NULL, prog, &new_array);
 	if (ret < 0)
 		goto unlock;

samples/bpf/bpf_load.c

@@ -193,8 +193,18 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
 		return -1;
 	}
 	event_fd[prog_cnt - 1] = efd;
-	ioctl(efd, PERF_EVENT_IOC_ENABLE, 0);
-	ioctl(efd, PERF_EVENT_IOC_SET_BPF, fd);
+	err = ioctl(efd, PERF_EVENT_IOC_ENABLE, 0);
+	if (err < 0) {
+		printf("ioctl PERF_EVENT_IOC_ENABLE failed err %s\n",
+		       strerror(errno));
+		return -1;
+	}
+	err = ioctl(efd, PERF_EVENT_IOC_SET_BPF, fd);
+	if (err < 0) {
+		printf("ioctl PERF_EVENT_IOC_SET_BPF failed err %s\n",
+		       strerror(errno));
+		return -1;
+	}
 
 	return 0;
 }

tools/bpf/bpftool/Documentation/Makefile

@@ -6,7 +6,7 @@ RM ?= rm -f
 
 # Make the path relative to DESTDIR, not prefix
 ifndef DESTDIR
-prefix?=$(HOME)
+prefix ?= /usr/local
 endif
 mandir ?= $(prefix)/share/man
 man8dir = $(mandir)/man8

tools/bpf/bpftool/Makefile

@@ -45,8 +45,8 @@ $(LIBBPF)-clean:
 	$(call QUIET_CLEAN, libbpf)
 	$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(OUTPUT) clean >/dev/null
 
-prefix = /usr
-bash_compdir ?= $(prefix)/share/bash-completion/completions
+prefix = /usr/local
+bash_compdir ?= /usr/share/bash-completion/completions
 
 CC = gcc
 
@@ -76,6 +76,7 @@ clean: $(LIBBPF)-clean
 	$(Q)rm -rf $(OUTPUT)bpftool $(OUTPUT)*.o $(OUTPUT)*.d
 
 install:
+	install -m 0755 -d $(prefix)/sbin
 	install $(OUTPUT)bpftool $(prefix)/sbin/bpftool
 	install -m 0755 -d $(bash_compdir)
 	install -m 0644 bash-completion/bpftool $(bash_compdir)
@@ -88,5 +89,5 @@ doc-install:
 
 FORCE:
 
-.PHONY: all clean FORCE
+.PHONY: all clean FORCE install doc doc-install
 .DEFAULT_GOAL := all

tools/bpf/bpftool/main.c

@@ -58,11 +58,19 @@ bool show_pinned;
 struct pinned_obj_table prog_table;
 struct pinned_obj_table map_table;
 
+static void __noreturn clean_and_exit(int i)
+{
+	if (json_output)
+		jsonw_destroy(&json_wtr);
+
+	exit(i);
+}
+
 void usage(void)
 {
 	last_do_help(last_argc - 1, last_argv + 1);
 
-	exit(-1);
+	clean_and_exit(-1);
 }
 
 static int do_help(int argc, char **argv)
@@ -280,6 +288,7 @@ int main(int argc, char **argv)
 	hash_init(prog_table.table);
 	hash_init(map_table.table);
 
+	opterr = 0;
 	while ((opt = getopt_long(argc, argv, "Vhpjf",
 				  options, NULL)) >= 0) {
 		switch (opt) {
@@ -291,13 +300,25 @@ int main(int argc, char **argv)
 			pretty_output = true;
 			/* fall through */
 		case 'j':
-			json_output = true;
+			if (!json_output) {
+				json_wtr = jsonw_new(stdout);
+				if (!json_wtr) {
+					p_err("failed to create JSON writer");
+					return -1;
+				}
+				json_output = true;
+			}
+			jsonw_pretty(json_wtr, pretty_output);
 			break;
 		case 'f':
 			show_pinned = true;
 			break;
 		default:
-			usage();
+			p_err("unrecognized option '%s'", argv[optind - 1]);
+			if (json_output)
+				clean_and_exit(-1);
+			else
+				usage();
 		}
 	}
 
@@ -306,15 +327,6 @@ int main(int argc, char **argv)
 	if (argc < 0)
 		usage();
 
-	if (json_output) {
-		json_wtr = jsonw_new(stdout);
-		if (!json_wtr) {
-			p_err("failed to create JSON writer");
-			return -1;
-		}
-		jsonw_pretty(json_wtr, pretty_output);
-	}
-
 	bfd_init();
 
 	ret = cmd_select(cmds, argc, argv, do_help);

tools/bpf/bpftool/main.h

@@ -41,6 +41,7 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <linux/bpf.h>
+#include <linux/compiler.h>
 #include <linux/kernel.h>
 #include <linux/hashtable.h>
 
@@ -50,7 +51,7 @@
 
 #define NEXT_ARG()	({ argc--; argv++; if (argc < 0) usage(); })
 #define NEXT_ARGP()	({ (*argc)--; (*argv)++; if (*argc < 0) usage(); })
-#define BAD_ARG()	({ p_err("what is '%s'?\n", *argv); -1; })
+#define BAD_ARG()	({ p_err("what is '%s'?", *argv); -1; })
 
 #define ERR_MAX_LEN	1024
 
@@ -80,7 +81,7 @@ void p_info(const char *fmt, ...);
 
 bool is_prefix(const char *pfx, const char *str);
 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep);
-void usage(void) __attribute__((noreturn));
+void usage(void) __noreturn;
 
 struct pinned_obj_table {
 	DECLARE_HASHTABLE(table, 16);

tools/testing/selftests/bpf/test_verifier_log.c

@@ -3,6 +3,8 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
+#include <sys/time.h>
+#include <sys/resource.h>
 
 #include <linux/bpf.h>
 #include <linux/filter.h>
@@ -131,11 +133,16 @@ static void test_log_bad(char *log, size_t log_len, int log_level)
 
 int main(int argc, char **argv)
 {
+	struct rlimit limit  = { RLIM_INFINITY, RLIM_INFINITY };
 	char full_log[LOG_SIZE];
 	char log[LOG_SIZE];
 	size_t want_len;
 	int i;
 
+	/* allow unlimited locked memory to have more consistent error code */
+	if (setrlimit(RLIMIT_MEMLOCK, &limit) < 0)
+		perror("Unable to lift memlock rlimit");
+
 	memset(log, 1, LOG_SIZE);
 
 	/* Test incorrect attr */