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authorLinus Torvalds <torvalds@linux-foundation.org>2018-06-06 18:39:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-06-06 18:39:49 -0700
commit1c8c5a9d38f607c0b6fd12c91cbe1a4418762a21 (patch)
treedcc97181d4d187252e0cc8fdf29d9b365fa3ffd0 /samples/bpf/task_fd_query_user.c
parent285767604576148fc1be7fcd112e4a90eb0d6ad2 (diff)
parent7170e6045a6a8b33f4fa5753589dc77b16198e2d (diff)
downloadlinux-1c8c5a9d38f607c0b6fd12c91cbe1a4418762a21.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
Diffstat (limited to 'samples/bpf/task_fd_query_user.c')
-rw-r--r--samples/bpf/task_fd_query_user.c382
1 files changed, 382 insertions, 0 deletions
diff --git a/samples/bpf/task_fd_query_user.c b/samples/bpf/task_fd_query_user.c
new file mode 100644
index 000000000000..8381d792f138
--- /dev/null
+++ b/samples/bpf/task_fd_query_user.c
@@ -0,0 +1,382 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdint.h>
+#include <fcntl.h>
+#include <linux/bpf.h>
+#include <sys/ioctl.h>
+#include <sys/resource.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "libbpf.h"
+#include "bpf_load.h"
+#include "bpf_util.h"
+#include "perf-sys.h"
+#include "trace_helpers.h"
+
+#define CHECK_PERROR_RET(condition) ({ \
+ int __ret = !!(condition); \
+ if (__ret) { \
+ printf("FAIL: %s:\n", __func__); \
+ perror(" "); \
+ return -1; \
+ } \
+})
+
+#define CHECK_AND_RET(condition) ({ \
+ int __ret = !!(condition); \
+ if (__ret) \
+ return -1; \
+})
+
+static __u64 ptr_to_u64(void *ptr)
+{
+ return (__u64) (unsigned long) ptr;
+}
+
+#define PMU_TYPE_FILE "/sys/bus/event_source/devices/%s/type"
+static int bpf_find_probe_type(const char *event_type)
+{
+ char buf[256];
+ int fd, ret;
+
+ ret = snprintf(buf, sizeof(buf), PMU_TYPE_FILE, event_type);
+ CHECK_PERROR_RET(ret < 0 || ret >= sizeof(buf));
+
+ fd = open(buf, O_RDONLY);
+ CHECK_PERROR_RET(fd < 0);
+
+ ret = read(fd, buf, sizeof(buf));
+ close(fd);
+ CHECK_PERROR_RET(ret < 0 || ret >= sizeof(buf));
+
+ errno = 0;
+ ret = (int)strtol(buf, NULL, 10);
+ CHECK_PERROR_RET(errno);
+ return ret;
+}
+
+#define PMU_RETPROBE_FILE "/sys/bus/event_source/devices/%s/format/retprobe"
+static int bpf_get_retprobe_bit(const char *event_type)
+{
+ char buf[256];
+ int fd, ret;
+
+ ret = snprintf(buf, sizeof(buf), PMU_RETPROBE_FILE, event_type);
+ CHECK_PERROR_RET(ret < 0 || ret >= sizeof(buf));
+
+ fd = open(buf, O_RDONLY);
+ CHECK_PERROR_RET(fd < 0);
+
+ ret = read(fd, buf, sizeof(buf));
+ close(fd);
+ CHECK_PERROR_RET(ret < 0 || ret >= sizeof(buf));
+ CHECK_PERROR_RET(strlen(buf) < strlen("config:"));
+
+ errno = 0;
+ ret = (int)strtol(buf + strlen("config:"), NULL, 10);
+ CHECK_PERROR_RET(errno);
+ return ret;
+}
+
+static int test_debug_fs_kprobe(int prog_fd_idx, const char *fn_name,
+ __u32 expected_fd_type)
+{
+ __u64 probe_offset, probe_addr;
+ __u32 len, prog_id, fd_type;
+ char buf[256];
+ int err;
+
+ len = sizeof(buf);
+ err = bpf_task_fd_query(getpid(), event_fd[prog_fd_idx], 0, buf, &len,
+ &prog_id, &fd_type, &probe_offset,
+ &probe_addr);
+ if (err < 0) {
+ printf("FAIL: %s, for event_fd idx %d, fn_name %s\n",
+ __func__, prog_fd_idx, fn_name);
+ perror(" :");
+ return -1;
+ }
+ if (strcmp(buf, fn_name) != 0 ||
+ fd_type != expected_fd_type ||
+ probe_offset != 0x0 || probe_addr != 0x0) {
+ printf("FAIL: bpf_trace_event_query(event_fd[%d]):\n",
+ prog_fd_idx);
+ printf("buf: %s, fd_type: %u, probe_offset: 0x%llx,"
+ " probe_addr: 0x%llx\n",
+ buf, fd_type, probe_offset, probe_addr);
+ return -1;
+ }
+ return 0;
+}
+
+static int test_nondebug_fs_kuprobe_common(const char *event_type,
+ const char *name, __u64 offset, __u64 addr, bool is_return,
+ char *buf, __u32 *buf_len, __u32 *prog_id, __u32 *fd_type,
+ __u64 *probe_offset, __u64 *probe_addr)
+{
+ int is_return_bit = bpf_get_retprobe_bit(event_type);
+ int type = bpf_find_probe_type(event_type);
+ struct perf_event_attr attr = {};
+ int fd;
+
+ if (type < 0 || is_return_bit < 0) {
+ printf("FAIL: %s incorrect type (%d) or is_return_bit (%d)\n",
+ __func__, type, is_return_bit);
+ return -1;
+ }
+
+ attr.sample_period = 1;
+ attr.wakeup_events = 1;
+ if (is_return)
+ attr.config |= 1 << is_return_bit;
+
+ if (name) {
+ attr.config1 = ptr_to_u64((void *)name);
+ attr.config2 = offset;
+ } else {
+ attr.config1 = 0;
+ attr.config2 = addr;
+ }
+ attr.size = sizeof(attr);
+ attr.type = type;
+
+ fd = sys_perf_event_open(&attr, -1, 0, -1, 0);
+ CHECK_PERROR_RET(fd < 0);
+
+ CHECK_PERROR_RET(ioctl(fd, PERF_EVENT_IOC_ENABLE, 0) < 0);
+ CHECK_PERROR_RET(ioctl(fd, PERF_EVENT_IOC_SET_BPF, prog_fd[0]) < 0);
+ CHECK_PERROR_RET(bpf_task_fd_query(getpid(), fd, 0, buf, buf_len,
+ prog_id, fd_type, probe_offset, probe_addr) < 0);
+
+ return 0;
+}
+
+static int test_nondebug_fs_probe(const char *event_type, const char *name,
+ __u64 offset, __u64 addr, bool is_return,
+ __u32 expected_fd_type,
+ __u32 expected_ret_fd_type,
+ char *buf, __u32 buf_len)
+{
+ __u64 probe_offset, probe_addr;
+ __u32 prog_id, fd_type;
+ int err;
+
+ err = test_nondebug_fs_kuprobe_common(event_type, name,
+ offset, addr, is_return,
+ buf, &buf_len, &prog_id,
+ &fd_type, &probe_offset,
+ &probe_addr);
+ if (err < 0) {
+ printf("FAIL: %s, "
+ "for name %s, offset 0x%llx, addr 0x%llx, is_return %d\n",
+ __func__, name ? name : "", offset, addr, is_return);
+ perror(" :");
+ return -1;
+ }
+ if ((is_return && fd_type != expected_ret_fd_type) ||
+ (!is_return && fd_type != expected_fd_type)) {
+ printf("FAIL: %s, incorrect fd_type %u\n",
+ __func__, fd_type);
+ return -1;
+ }
+ if (name) {
+ if (strcmp(name, buf) != 0) {
+ printf("FAIL: %s, incorrect buf %s\n", __func__, buf);
+ return -1;
+ }
+ if (probe_offset != offset) {
+ printf("FAIL: %s, incorrect probe_offset 0x%llx\n",
+ __func__, probe_offset);
+ return -1;
+ }
+ } else {
+ if (buf_len != 0) {
+ printf("FAIL: %s, incorrect buf %p\n",
+ __func__, buf);
+ return -1;
+ }
+
+ if (probe_addr != addr) {
+ printf("FAIL: %s, incorrect probe_addr 0x%llx\n",
+ __func__, probe_addr);
+ return -1;
+ }
+ }
+ return 0;
+}
+
+static int test_debug_fs_uprobe(char *binary_path, long offset, bool is_return)
+{
+ const char *event_type = "uprobe";
+ struct perf_event_attr attr = {};
+ char buf[256], event_alias[256];
+ __u64 probe_offset, probe_addr;
+ __u32 len, prog_id, fd_type;
+ int err, res, kfd, efd;
+ ssize_t bytes;
+
+ snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/%s_events",
+ event_type);
+ kfd = open(buf, O_WRONLY | O_APPEND, 0);
+ CHECK_PERROR_RET(kfd < 0);
+
+ res = snprintf(event_alias, sizeof(event_alias), "test_%d", getpid());
+ CHECK_PERROR_RET(res < 0 || res >= sizeof(event_alias));
+
+ res = snprintf(buf, sizeof(buf), "%c:%ss/%s %s:0x%lx",
+ is_return ? 'r' : 'p', event_type, event_alias,
+ binary_path, offset);
+ CHECK_PERROR_RET(res < 0 || res >= sizeof(buf));
+ CHECK_PERROR_RET(write(kfd, buf, strlen(buf)) < 0);
+
+ close(kfd);
+ kfd = -1;
+
+ snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id",
+ event_type, event_alias);
+ efd = open(buf, O_RDONLY, 0);
+ CHECK_PERROR_RET(efd < 0);
+
+ bytes = read(efd, buf, sizeof(buf));
+ CHECK_PERROR_RET(bytes <= 0 || bytes >= sizeof(buf));
+ close(efd);
+ buf[bytes] = '\0';
+
+ attr.config = strtol(buf, NULL, 0);
+ attr.type = PERF_TYPE_TRACEPOINT;
+ attr.sample_period = 1;
+ attr.wakeup_events = 1;
+ kfd = sys_perf_event_open(&attr, -1, 0, -1, PERF_FLAG_FD_CLOEXEC);
+ CHECK_PERROR_RET(kfd < 0);
+ CHECK_PERROR_RET(ioctl(kfd, PERF_EVENT_IOC_SET_BPF, prog_fd[0]) < 0);
+ CHECK_PERROR_RET(ioctl(kfd, PERF_EVENT_IOC_ENABLE, 0) < 0);
+
+ len = sizeof(buf);
+ err = bpf_task_fd_query(getpid(), kfd, 0, buf, &len,
+ &prog_id, &fd_type, &probe_offset,
+ &probe_addr);
+ if (err < 0) {
+ printf("FAIL: %s, binary_path %s\n", __func__, binary_path);
+ perror(" :");
+ return -1;
+ }
+ if ((is_return && fd_type != BPF_FD_TYPE_URETPROBE) ||
+ (!is_return && fd_type != BPF_FD_TYPE_UPROBE)) {
+ printf("FAIL: %s, incorrect fd_type %u\n", __func__,
+ fd_type);
+ return -1;
+ }
+ if (strcmp(binary_path, buf) != 0) {
+ printf("FAIL: %s, incorrect buf %s\n", __func__, buf);
+ return -1;
+ }
+ if (probe_offset != offset) {
+ printf("FAIL: %s, incorrect probe_offset 0x%llx\n", __func__,
+ probe_offset);
+ return -1;
+ }
+
+ close(kfd);
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ struct rlimit r = {1024*1024, RLIM_INFINITY};
+ extern char __executable_start;
+ char filename[256], buf[256];
+ __u64 uprobe_file_offset;
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+ if (setrlimit(RLIMIT_MEMLOCK, &r)) {
+ perror("setrlimit(RLIMIT_MEMLOCK)");
+ return 1;
+ }
+
+ if (load_kallsyms()) {
+ printf("failed to process /proc/kallsyms\n");
+ return 1;
+ }
+
+ if (load_bpf_file(filename)) {
+ printf("%s", bpf_log_buf);
+ return 1;
+ }
+
+ /* test two functions in the corresponding *_kern.c file */
+ CHECK_AND_RET(test_debug_fs_kprobe(0, "blk_start_request",
+ BPF_FD_TYPE_KPROBE));
+ CHECK_AND_RET(test_debug_fs_kprobe(1, "blk_account_io_completion",
+ BPF_FD_TYPE_KRETPROBE));
+
+ /* test nondebug fs kprobe */
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", "bpf_check", 0x0, 0x0,
+ false, BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ buf, sizeof(buf)));
+#ifdef __x86_64__
+ /* set a kprobe on "bpf_check + 0x5", which is x64 specific */
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", "bpf_check", 0x5, 0x0,
+ false, BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ buf, sizeof(buf)));
+#endif
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", "bpf_check", 0x0, 0x0,
+ true, BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ buf, sizeof(buf)));
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", NULL, 0x0,
+ ksym_get_addr("bpf_check"), false,
+ BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ buf, sizeof(buf)));
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", NULL, 0x0,
+ ksym_get_addr("bpf_check"), false,
+ BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ NULL, 0));
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", NULL, 0x0,
+ ksym_get_addr("bpf_check"), true,
+ BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ buf, sizeof(buf)));
+ CHECK_AND_RET(test_nondebug_fs_probe("kprobe", NULL, 0x0,
+ ksym_get_addr("bpf_check"), true,
+ BPF_FD_TYPE_KPROBE,
+ BPF_FD_TYPE_KRETPROBE,
+ 0, 0));
+
+ /* test nondebug fs uprobe */
+ /* the calculation of uprobe file offset is based on gcc 7.3.1 on x64
+ * and the default linker script, which defines __executable_start as
+ * the start of the .text section. The calculation could be different
+ * on different systems with different compilers. The right way is
+ * to parse the ELF file. We took a shortcut here.
+ */
+ uprobe_file_offset = (__u64)main - (__u64)&__executable_start;
+ CHECK_AND_RET(test_nondebug_fs_probe("uprobe", (char *)argv[0],
+ uprobe_file_offset, 0x0, false,
+ BPF_FD_TYPE_UPROBE,
+ BPF_FD_TYPE_URETPROBE,
+ buf, sizeof(buf)));
+ CHECK_AND_RET(test_nondebug_fs_probe("uprobe", (char *)argv[0],
+ uprobe_file_offset, 0x0, true,
+ BPF_FD_TYPE_UPROBE,
+ BPF_FD_TYPE_URETPROBE,
+ buf, sizeof(buf)));
+
+ /* test debug fs uprobe */
+ CHECK_AND_RET(test_debug_fs_uprobe((char *)argv[0], uprobe_file_offset,
+ false));
+ CHECK_AND_RET(test_debug_fs_uprobe((char *)argv[0], uprobe_file_offset,
+ true));
+
+ return 0;
+}