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

Daniel Borkmann says:

====================
pull-request: bpf-next 2018-01-07

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

The main changes are:

1) Add a start of a framework for extending struct xdp_buff without
   having the overhead of populating every data at runtime. Idea
   is to have a new per-queue struct xdp_rxq_info that holds read
   mostly data (currently that is, queue number and a pointer to
   the corresponding netdev) which is set up during rxqueue config
   time. When a XDP program is invoked, struct xdp_buff holds a
   pointer to struct xdp_rxq_info that the BPF program can then
   walk. The user facing BPF program that uses struct xdp_md for
   context can use these members directly, and the verifier rewrites
   context access transparently by walking the xdp_rxq_info and
   net_device pointers to load the data, from Jesper.

2) Redo the reporting of offload device information to user space
   such that it works in combination with network namespaces. The
   latter is reported through a device/inode tuple as similarly
   done in other subsystems as well (e.g. perf) in order to identify
   the namespace. For this to work, ns_get_path() has been generalized
   such that the namespace can be retrieved not only from a specific
   task (perf case), but also from a callback where we deduce the
   netns (ns_common) from a netdevice. bpftool support using the new
   uapi info and extensive test cases for test_offload.py in BPF
   selftests have been added as well, from Jakub.

3) Add two bpftool improvements: i) properly report the bpftool
   version such that it corresponds to the version from the kernel
   source tree. So pick the right linux/version.h from the source
   tree instead of the installed one. ii) fix bpftool and also
   bpf_jit_disasm build with bintutils >= 2.9. The reason for the
   build breakage is that binutils library changed the function
   signature to select the disassembler. Given this is needed in
   multiple tools, add a proper feature detection to the
   tools/build/features infrastructure, from Roman.

4) Implement the BPF syscall command BPF_MAP_GET_NEXT_KEY for the
   stacktrace map. It is currently unimplemented, but there are
   use cases where user space needs to walk all stacktrace map
   entries e.g. for dumping or deleting map entries w/o having to
   close and recreate the map. Add BPF selftests along with it,
   from Yonghong.

5) Few follow-up cleanups for the bpftool cgroup code: i) rename
   the cgroup 'list' command into 'show' as we have it for other
   subcommands as well, ii) then alias the 'show' command such that
   'list' is accepted which is also common practice in iproute2,
   and iii) remove couple of newlines from error messages using
   p_err(), from Jakub.

6) Two follow-up cleanups to sockmap code: i) remove the unused
   bpf_compute_data_end_sk_skb() function and ii) only build the
   sockmap infrastructure when CONFIG_INET is enabled since it's
   only aware of TCP sockets at this time, from John.
====================

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

4 files changed, 291 insertions, 12 deletions

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 1304753d29ea..a8aa7e251c8e 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -19,7 +19,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
 TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
 	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \
 	sockmap_verdict_prog.o dev_cgroup.o sample_ret0.o test_tracepoint.o \
-	test_l4lb_noinline.o test_xdp_noinline.o
+	test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o
 
 TEST_PROGS := test_kmod.sh test_xdp_redirect.sh test_xdp_meta.sh \
 	test_offload.py
diff --git a/tools/testing/selftests/bpf/test_offload.py b/tools/testing/selftests/bpf/test_offload.py
index c940505c2978..e3c750f17cb8 100755
--- a/tools/testing/selftests/bpf/test_offload.py
+++ b/tools/testing/selftests/bpf/test_offload.py
@@ -18,6 +18,8 @@ import argparse
 import json
 import os
 import pprint
+import random
+import string
 import subprocess
 import time
 
@@ -27,6 +29,7 @@ bpf_test_dir = os.path.dirname(os.path.realpath(__file__))
 pp = pprint.PrettyPrinter()
 devs = [] # devices we created for clean up
 files = [] # files to be removed
+netns = [] # net namespaces to be removed
 
 def log_get_sec(level=0):
     return "*" * (log_level + level)
@@ -128,22 +131,25 @@ def rm(f):
     if f in files:
         files.remove(f)
 
-def tool(name, args, flags, JSON=True, fail=True):
+def tool(name, args, flags, JSON=True, ns="", fail=True):
     params = ""
     if JSON:
         params += "%s " % (flags["json"])
 
-    ret, out = cmd(name + " " + params + args, fail=fail)
+    if ns != "":
+        ns = "ip netns exec %s " % (ns)
+
+    ret, out = cmd(ns + name + " " + params + args, fail=fail)
     if JSON and len(out.strip()) != 0:
         return ret, json.loads(out)
     else:
         return ret, out
 
-def bpftool(args, JSON=True, fail=True):
-    return tool("bpftool", args, {"json":"-p"}, JSON=JSON, fail=fail)
+def bpftool(args, JSON=True, ns="", fail=True):
+    return tool("bpftool", args, {"json":"-p"}, JSON=JSON, ns=ns, fail=fail)
 
-def bpftool_prog_list(expected=None):
-    _, progs = bpftool("prog show", JSON=True, fail=True)
+def bpftool_prog_list(expected=None, ns=""):
+    _, progs = bpftool("prog show", JSON=True, ns=ns, fail=True)
     if expected is not None:
         if len(progs) != expected:
             fail(True, "%d BPF programs loaded, expected %d" %
@@ -158,13 +164,13 @@ def bpftool_prog_list_wait(expected=0, n_retry=20):
         time.sleep(0.05)
     raise Exception("Time out waiting for program counts to stabilize want %d, have %d" % (expected, nprogs))
 
-def ip(args, force=False, JSON=True, fail=True):
+def ip(args, force=False, JSON=True, ns="", fail=True):
     if force:
         args = "-force " + args
-    return tool("ip", args, {"json":"-j"}, JSON=JSON, fail=fail)
+    return tool("ip", args, {"json":"-j"}, JSON=JSON, ns=ns, fail=fail)
 
-def tc(args, JSON=True, fail=True):
-    return tool("tc", args, {"json":"-p"}, JSON=JSON, fail=fail)
+def tc(args, JSON=True, ns="", fail=True):
+    return tool("tc", args, {"json":"-p"}, JSON=JSON, ns=ns, fail=fail)
 
 def ethtool(dev, opt, args, fail=True):
     return cmd("ethtool %s %s %s" % (opt, dev["ifname"], args), fail=fail)
@@ -178,6 +184,15 @@ def bpf_pinned(name):
 def bpf_bytecode(bytecode):
     return "bytecode \"%s\"" % (bytecode)
 
+def mknetns(n_retry=10):
+    for i in range(n_retry):
+        name = ''.join([random.choice(string.ascii_letters) for i in range(8)])
+        ret, _ = ip("netns add %s" % (name), fail=False)
+        if ret == 0:
+            netns.append(name)
+            return name
+    return None
+
 class DebugfsDir:
     """
     Class for accessing DebugFS directories as a dictionary.
@@ -237,6 +252,8 @@ class NetdevSim:
         self.dev = self._netdevsim_create()
         devs.append(self)
 
+        self.ns = ""
+
         self.dfs_dir = '/sys/kernel/debug/netdevsim/%s' % (self.dev['ifname'])
         self.dfs_refresh()
 
@@ -257,7 +274,7 @@ class NetdevSim:
 
     def remove(self):
         devs.remove(self)
-        ip("link del dev %s" % (self.dev["ifname"]))
+        ip("link del dev %s" % (self.dev["ifname"]), ns=self.ns)
 
     def dfs_refresh(self):
         self.dfs = DebugfsDir(self.dfs_dir)
@@ -285,6 +302,11 @@ class NetdevSim:
             time.sleep(0.05)
         raise Exception("Time out waiting for program counts to stabilize want %d/%d, have %d bound, %d loaded" % (bound, total, nbound, nprogs))
 
+    def set_ns(self, ns):
+        name = "1" if ns == "" else ns
+        ip("link set dev %s netns %s" % (self.dev["ifname"], name), ns=self.ns)
+        self.ns = ns
+
     def set_mtu(self, mtu, fail=True):
         return ip("link set dev %s mtu %d" % (self.dev["ifname"], mtu),
                   fail=fail)
@@ -372,6 +394,8 @@ def clean_up():
         dev.remove()
     for f in files:
         cmd("rm -f %s" % (f))
+    for ns in netns:
+        cmd("ip netns delete %s" % (ns))
 
 def pin_prog(file_name, idx=0):
     progs = bpftool_prog_list(expected=(idx + 1))
@@ -381,6 +405,35 @@ def pin_prog(file_name, idx=0):
 
     return file_name, bpf_pinned(file_name)
 
+def check_dev_info(other_ns, ns, pin_file=None, removed=False):
+    if removed:
+        bpftool_prog_list(expected=0)
+        ret, err = bpftool("prog show pin %s" % (pin_file), fail=False)
+        fail(ret == 0, "Showing prog with removed device did not fail")
+        fail(err["error"].find("No such device") == -1,
+             "Showing prog with removed device expected ENODEV, error is %s" %
+             (err["error"]))
+        return
+    progs = bpftool_prog_list(expected=int(not removed), ns=ns)
+    prog = progs[0]
+
+    fail("dev" not in prog.keys(), "Device parameters not reported")
+    dev = prog["dev"]
+    fail("ifindex" not in dev.keys(), "Device parameters not reported")
+    fail("ns_dev" not in dev.keys(), "Device parameters not reported")
+    fail("ns_inode" not in dev.keys(), "Device parameters not reported")
+
+    if not removed and not other_ns:
+        fail("ifname" not in dev.keys(), "Ifname not reported")
+        fail(dev["ifname"] != sim["ifname"],
+             "Ifname incorrect %s vs %s" % (dev["ifname"], sim["ifname"]))
+    else:
+        fail("ifname" in dev.keys(), "Ifname is reported for other ns")
+        if removed:
+            fail(dev["ifindex"] != 0, "Device perameters not zero on removed")
+            fail(dev["ns_dev"] != 0, "Device perameters not zero on removed")
+            fail(dev["ns_inode"] != 0, "Device perameters not zero on removed")
+
 # Parse command line
 parser = argparse.ArgumentParser()
 parser.add_argument("--log", help="output verbose log to given file")
@@ -417,6 +470,12 @@ for s in samples:
     skip(ret != 0, "sample %s/%s not found, please compile it" %
          (bpf_test_dir, s))
 
+# Check if net namespaces seem to work
+ns = mknetns()
+skip(ns is None, "Could not create a net namespace")
+cmd("ip netns delete %s" % (ns))
+netns = []
+
 try:
     obj = bpf_obj("sample_ret0.o")
     bytecode = bpf_bytecode("1,6 0 0 4294967295,")
@@ -549,6 +608,8 @@ try:
     progs = bpftool_prog_list(expected=1)
     fail(ipl["xdp"]["prog"]["id"] != progs[0]["id"],
          "Loaded program has wrong ID")
+    fail("dev" in progs[0].keys(),
+         "Device parameters reported for non-offloaded program")
 
     start_test("Test XDP prog replace with bad flags...")
     ret, _ = sim.set_xdp(obj, "offload", force=True, fail=False)
@@ -673,6 +734,35 @@ try:
     fail(time_diff < delay_sec, "Removal process took %s, expected %s" %
          (time_diff, delay_sec))
 
+    # Remove all pinned files and reinstantiate the netdev
+    clean_up()
+    bpftool_prog_list_wait(expected=0)
+
+    sim = NetdevSim()
+    sim.set_ethtool_tc_offloads(True)
+    sim.set_xdp(obj, "offload")
+
+    start_test("Test bpftool bound info reporting (own ns)...")
+    check_dev_info(False, "")
+
+    start_test("Test bpftool bound info reporting (other ns)...")
+    ns = mknetns()
+    sim.set_ns(ns)
+    check_dev_info(True, "")
+
+    start_test("Test bpftool bound info reporting (remote ns)...")
+    check_dev_info(False, ns)
+
+    start_test("Test bpftool bound info reporting (back to own ns)...")
+    sim.set_ns("")
+    check_dev_info(False, "")
+
+    pin_file, _ = pin_prog("/sys/fs/bpf/tmp")
+    sim.remove()
+
+    start_test("Test bpftool bound info reporting (removed dev)...")
+    check_dev_info(True, "", pin_file=pin_file, removed=True)
+
     print("%s: OK" % (os.path.basename(__file__)))
 
 finally:
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index 09087ab12293..b549308abd19 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -837,6 +837,132 @@ static void test_tp_attach_query(void)
 	free(query);
 }
 
+static int compare_map_keys(int map1_fd, int map2_fd)
+{
+	__u32 key, next_key;
+	char val_buf[PERF_MAX_STACK_DEPTH * sizeof(__u64)];
+	int err;
+
+	err = bpf_map_get_next_key(map1_fd, NULL, &key);
+	if (err)
+		return err;
+	err = bpf_map_lookup_elem(map2_fd, &key, val_buf);
+	if (err)
+		return err;
+
+	while (bpf_map_get_next_key(map1_fd, &key, &next_key) == 0) {
+		err = bpf_map_lookup_elem(map2_fd, &next_key, val_buf);
+		if (err)
+			return err;
+
+		key = next_key;
+	}
+	if (errno != ENOENT)
+		return -1;
+
+	return 0;
+}
+
+static void test_stacktrace_map()
+{
+	int control_map_fd, stackid_hmap_fd, stackmap_fd;
+	const char *file = "./test_stacktrace_map.o";
+	int bytes, efd, err, pmu_fd, prog_fd;
+	struct perf_event_attr attr = {};
+	__u32 key, val, duration = 0;
+	struct bpf_object *obj;
+	char buf[256];
+
+	err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd);
+	if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
+		goto out;
+
+	/* Get the ID for the sched/sched_switch tracepoint */
+	snprintf(buf, sizeof(buf),
+		 "/sys/kernel/debug/tracing/events/sched/sched_switch/id");
+	efd = open(buf, O_RDONLY, 0);
+	if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno))
+		goto close_prog;
+
+	bytes = read(efd, buf, sizeof(buf));
+	close(efd);
+	if (CHECK(bytes <= 0 || bytes >= sizeof(buf),
+		  "read", "bytes %d errno %d\n", bytes, errno))
+		goto close_prog;
+
+	/* Open the perf event and attach bpf progrram */
+	attr.config = strtol(buf, NULL, 0);
+	attr.type = PERF_TYPE_TRACEPOINT;
+	attr.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN;
+	attr.sample_period = 1;
+	attr.wakeup_events = 1;
+	pmu_fd = syscall(__NR_perf_event_open, &attr, -1 /* pid */,
+			 0 /* cpu 0 */, -1 /* group id */,
+			 0 /* flags */);
+	if (CHECK(pmu_fd < 0, "perf_event_open", "err %d errno %d\n",
+		  pmu_fd, errno))
+		goto close_prog;
+
+	err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
+	if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n",
+		  err, errno))
+		goto close_pmu;
+
+	err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
+	if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n",
+		  err, errno))
+		goto disable_pmu;
+
+	/* find map fds */
+	control_map_fd = bpf_find_map(__func__, obj, "control_map");
+	if (CHECK(control_map_fd < 0, "bpf_find_map control_map",
+		  "err %d errno %d\n", err, errno))
+		goto disable_pmu;
+
+	stackid_hmap_fd = bpf_find_map(__func__, obj, "stackid_hmap");
+	if (CHECK(stackid_hmap_fd < 0, "bpf_find_map stackid_hmap",
+		  "err %d errno %d\n", err, errno))
+		goto disable_pmu;
+
+	stackmap_fd = bpf_find_map(__func__, obj, "stackmap");
+	if (CHECK(stackmap_fd < 0, "bpf_find_map stackmap", "err %d errno %d\n",
+		  err, errno))
+		goto disable_pmu;
+
+	/* give some time for bpf program run */
+	sleep(1);
+
+	/* disable stack trace collection */
+	key = 0;
+	val = 1;
+	bpf_map_update_elem(control_map_fd, &key, &val, 0);
+
+	/* for every element in stackid_hmap, we can find a corresponding one
+	 * in stackmap, and vise versa.
+	 */
+	err = compare_map_keys(stackid_hmap_fd, stackmap_fd);
+	if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap",
+		  "err %d errno %d\n", err, errno))
+		goto disable_pmu;
+
+	err = compare_map_keys(stackmap_fd, stackid_hmap_fd);
+	if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap",
+		  "err %d errno %d\n", err, errno))
+		; /* fall through */
+
+disable_pmu:
+	ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE);
+
+close_pmu:
+	close(pmu_fd);
+
+close_prog:
+	bpf_object__close(obj);
+
+out:
+	return;
+}
+
 int main(void)
 {
 	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
@@ -852,6 +978,7 @@ int main(void)
 	test_pkt_md_access();
 	test_obj_name();
 	test_tp_attach_query();
+	test_stacktrace_map();
 
 	printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
 	return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
diff --git a/tools/testing/selftests/bpf/test_stacktrace_map.c b/tools/testing/selftests/bpf/test_stacktrace_map.c
new file mode 100644
index 000000000000..76d85c5d08bd
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_stacktrace_map.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Facebook
+
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+#ifndef PERF_MAX_STACK_DEPTH
+#define PERF_MAX_STACK_DEPTH         127
+#endif
+
+struct bpf_map_def SEC("maps") control_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u32),
+	.max_entries = 1,
+};
+
+struct bpf_map_def SEC("maps") stackid_hmap = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u32),
+	.max_entries = 10000,
+};
+
+struct bpf_map_def SEC("maps") stackmap = {
+	.type = BPF_MAP_TYPE_STACK_TRACE,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u64) * PERF_MAX_STACK_DEPTH,
+	.max_entries = 10000,
+};
+
+/* taken from /sys/kernel/debug/tracing/events/sched/sched_switch/format */
+struct sched_switch_args {
+	unsigned long long pad;
+	char prev_comm[16];
+	int prev_pid;
+	int prev_prio;
+	long long prev_state;
+	char next_comm[16];
+	int next_pid;
+	int next_prio;
+};
+
+SEC("tracepoint/sched/sched_switch")
+int oncpu(struct sched_switch_args *ctx)
+{
+	__u32 key = 0, val = 0, *value_p;
+
+	value_p = bpf_map_lookup_elem(&control_map, &key);
+	if (value_p && *value_p)
+		return 0; /* skip if non-zero *value_p */
+
+	/* The size of stackmap and stackid_hmap should be the same */
+	key = bpf_get_stackid(ctx, &stackmap, 0);
+	if ((int)key >= 0)
+		bpf_map_update_elem(&stackid_hmap, &key, &val, 0);
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+__u32 _version SEC("version") = 1; /* ignored by tracepoints, required by libbpf.a */