| Message ID | 20191009152632.14218-5-cneirabustos@gmail.com |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | BPF: New helper to obtain namespace data from current task | expand |
On Wed, Oct 9, 2019 at 8:29 AM Carlos Neira <cneirabustos@gmail.com> wrote: > > Self tests added for new helper > > Signed-off-by: Carlos Neira <cneirabustos@gmail.com> > --- > tools/testing/selftests/bpf/bpf_helpers.h | 4 + > .../bpf/prog_tests/get_ns_current_pid_tgid.c | 85 +++++++++++++++++++ > .../bpf/progs/get_ns_current_pid_tgid_kern.c | 53 ++++++++++++ > 3 files changed, 142 insertions(+) > create mode 100644 tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c > create mode 100644 tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c > > diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h > index 54a50699bbfd..16261b23e011 100644 > --- a/tools/testing/selftests/bpf/bpf_helpers.h > +++ b/tools/testing/selftests/bpf/bpf_helpers.h > @@ -233,6 +233,10 @@ static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal; > static long long (*bpf_tcp_gen_syncookie)(struct bpf_sock *sk, void *ip, > int ip_len, void *tcp, int tcp_len) = > (void *) BPF_FUNC_tcp_gen_syncookie; > +static unsigned long long (*bpf_get_ns_current_pid_tgid)(struct bpf_pidns_info *nsinfo, > + unsigned int buf_size) = > + (void *) BPF_FUNC_get_ns_current_pid_tgid; > + This is obsolete as of two days ago :) We now generate this automatically from the bpf.h's documentation (which is currently broken for your helper, I replied on respective patch). So please pull latest bpf-next and rebase. > > /* llvm builtin functions that eBPF C program may use to > * emit BPF_LD_ABS and BPF_LD_IND instructions > diff --git a/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c b/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c > new file mode 100644 > index 000000000000..a7bff0ef6677 > --- /dev/null > +++ b/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c > @@ -0,0 +1,85 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */ > +#include <test_progs.h> > +#include <sys/stat.h> > +#include <sys/types.h> > +#include <sys/stat.h> > +#include <unistd.h> > +#include <sys/syscall.h> > + > +void test_get_ns_current_pid_tgid(void) > +{ > + const char *probe_name = "syscalls/sys_enter_nanosleep"; > + const char *file = "get_ns_current_pid_tgid_kern.o"; > + int ns_data_map_fd, duration = 0; > + struct perf_event_attr attr = {}; > + int err, efd, prog_fd, pmu_fd; > + __u64 ino, dev, id, nspid; > + struct bpf_object *obj; > + struct stat st; > + __u32 key = 0; > + 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)) > + return; > + > + ns_data_map_fd = bpf_find_map(__func__, obj, "ns_data_map"); > + if (CHECK_FAIL(ns_data_map_fd < 0)) > + goto close_prog; > + > + pid_t tid = syscall(SYS_gettid); > + pid_t pid = getpid(); > + > + id = (__u64) tid << 32 | pid; > + bpf_map_update_elem(ns_data_map_fd, &key, &id, 0); > + > + if (stat("/proc/self/ns/pid", &st)) CHECK() or CHECK_FAIL() ? > + goto close_prog; > + > + dev = st.st_dev; > + ino = st.st_ino; > + key = 1; > + bpf_map_update_elem(ns_data_map_fd, &key, &dev, 0); > + key = 2; > + bpf_map_update_elem(ns_data_map_fd, &key, &ino, 0); > + > + snprintf(buf, sizeof(buf), > + "/sys/kernel/debug/tracing/events/%s/id", probe_name); > + efd = open(buf, O_RDONLY, 0); > + read(efd, buf, sizeof(buf)); > + close(efd); > + attr.config = strtol(buf, NULL, 0); > + attr.type = PERF_TYPE_TRACEPOINT; > + attr.sample_type = PERF_SAMPLE_RAW; > + attr.sample_period = 1; > + attr.wakeup_events = 1; > + > + pmu_fd = syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0); > + if (CHECK_FAIL(pmu_fd < 0)) > + goto cleanup; > + > + err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); > + if (CHECK_FAIL(err)) > + goto cleanup; > + > + err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); > + if (CHECK_FAIL(err)) > + goto cleanup; All this attaching boilerplate is now obsolete as well, stick to bpf_program__attach_tracepoint(). But even better, use RAW_TRACEPOINT. > + > + /* trigger some syscalls */ > + sleep(1); > + key = 3; > + err = bpf_map_lookup_elem(ns_data_map_fd, &key, &nspid); > + if (CHECK_FAIL(err)) > + goto cleanup; > + > + if (CHECK(id != nspid, "Compare user pid/tgid vs. bpf pid/tgid", > + "Userspace pid/tgid %llu EBPF pid/tgid %llu\n", id, nspid)) > + goto cleanup; > + > +cleanup: > + close(pmu_fd); > +close_prog: > + bpf_object__close(obj); > +} > diff --git a/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c b/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c > new file mode 100644 > index 000000000000..3659aaa7c71f > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c > @@ -0,0 +1,53 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */ > + > +#include <linux/bpf.h> > +#include "bpf_helpers.h" > + > +struct { > + __uint(type, BPF_MAP_TYPE_ARRAY); > + __uint(max_entries, 4); > + __type(key, __u32); > + __type(value, __u64); > +} ns_data_map SEC(".maps"); > + > + > +SEC("tracepoint/syscalls/sys_enter_nanosleep") > +int trace(void *ctx) > +{ > + __u64 *val, *inum, *dev, nspidtgid, *expected_pid; > + struct bpf_pidns_info nsdata; > + __u32 key = 1; > + > + dev = bpf_map_lookup_elem(&ns_data_map, &key); > + if (!dev) > + return 0; > + key = 2; > + inum = bpf_map_lookup_elem(&ns_data_map, &key); > + if (!inum) > + return 0; > + > + nsdata.dev = *dev; > + nsdata.inum = *inum; > + > + if (bpf_get_ns_current_pid_tgid(&nsdata, sizeof(struct bpf_pidns_info))) > + return 0; > + > + nspidtgid = (__u64)nsdata.tgid << 32 | nsdata.pid; > + key = 0; > + expected_pid = bpf_map_lookup_elem(&ns_data_map, &key); > + > + if (!expected_pid || *expected_pid != nspidtgid) > + return 0; > + > + key = 3; > + val = bpf_map_lookup_elem(&ns_data_map, &key); Please, use global data for this, will make this BPF program much shorter, cleaner, and up to the point. See recent patch by Daniel T. Lee, or some of the tests I added (e.g., progs/test_core_reloc_kernel.c) > + > + if (val) > + *val = nspidtgid; > + > + return 0; > +} > + > +char _license[] SEC("license") = "GPL"; > +__u32 _version SEC("version") = 1; You can drop version now (recent stuff), it's not required by libbpf anymore. > -- > 2.20.1 >
On Wed, Oct 09, 2019 at 09:26:32AM -0700, Andrii Nakryiko wrote: > On Wed, Oct 9, 2019 at 8:29 AM Carlos Neira <cneirabustos@gmail.com> wrote: > > > > Self tests added for new helper > > > > Signed-off-by: Carlos Neira <cneirabustos@gmail.com> > > --- > > tools/testing/selftests/bpf/bpf_helpers.h | 4 + > > .../bpf/prog_tests/get_ns_current_pid_tgid.c | 85 +++++++++++++++++++ > > .../bpf/progs/get_ns_current_pid_tgid_kern.c | 53 ++++++++++++ > > 3 files changed, 142 insertions(+) > > create mode 100644 tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c > > create mode 100644 tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c > > > > diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h > > index 54a50699bbfd..16261b23e011 100644 > > --- a/tools/testing/selftests/bpf/bpf_helpers.h > > +++ b/tools/testing/selftests/bpf/bpf_helpers.h > > @@ -233,6 +233,10 @@ static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal; > > static long long (*bpf_tcp_gen_syncookie)(struct bpf_sock *sk, void *ip, > > int ip_len, void *tcp, int tcp_len) = > > (void *) BPF_FUNC_tcp_gen_syncookie; > > +static unsigned long long (*bpf_get_ns_current_pid_tgid)(struct bpf_pidns_info *nsinfo, > > + unsigned int buf_size) = > > + (void *) BPF_FUNC_get_ns_current_pid_tgid; > > + > > This is obsolete as of two days ago :) We now generate this > automatically from the bpf.h's documentation (which is currently > broken for your helper, I replied on respective patch). So please pull > latest bpf-next and rebase. > > > > > /* llvm builtin functions that eBPF C program may use to > > * emit BPF_LD_ABS and BPF_LD_IND instructions > > diff --git a/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c b/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c > > new file mode 100644 > > index 000000000000..a7bff0ef6677 > > --- /dev/null > > +++ b/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c > > @@ -0,0 +1,85 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */ > > +#include <test_progs.h> > > +#include <sys/stat.h> > > +#include <sys/types.h> > > +#include <sys/stat.h> > > +#include <unistd.h> > > +#include <sys/syscall.h> > > + > > +void test_get_ns_current_pid_tgid(void) > > +{ > > + const char *probe_name = "syscalls/sys_enter_nanosleep"; > > + const char *file = "get_ns_current_pid_tgid_kern.o"; > > + int ns_data_map_fd, duration = 0; > > + struct perf_event_attr attr = {}; > > + int err, efd, prog_fd, pmu_fd; > > + __u64 ino, dev, id, nspid; > > + struct bpf_object *obj; > > + struct stat st; > > + __u32 key = 0; > > + 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)) > > + return; > > + > > + ns_data_map_fd = bpf_find_map(__func__, obj, "ns_data_map"); > > + if (CHECK_FAIL(ns_data_map_fd < 0)) > > + goto close_prog; > > + > > + pid_t tid = syscall(SYS_gettid); > > + pid_t pid = getpid(); > > + > > + id = (__u64) tid << 32 | pid; > > + bpf_map_update_elem(ns_data_map_fd, &key, &id, 0); > > + > > + if (stat("/proc/self/ns/pid", &st)) > > CHECK() or CHECK_FAIL() ? > > > + goto close_prog; > > + > > + dev = st.st_dev; > > + ino = st.st_ino; > > + key = 1; > > + bpf_map_update_elem(ns_data_map_fd, &key, &dev, 0); > > + key = 2; > > + bpf_map_update_elem(ns_data_map_fd, &key, &ino, 0); > > + > > + snprintf(buf, sizeof(buf), > > + "/sys/kernel/debug/tracing/events/%s/id", probe_name); > > + efd = open(buf, O_RDONLY, 0); > > + read(efd, buf, sizeof(buf)); > > + close(efd); > > + attr.config = strtol(buf, NULL, 0); > > + attr.type = PERF_TYPE_TRACEPOINT; > > + attr.sample_type = PERF_SAMPLE_RAW; > > + attr.sample_period = 1; > > + attr.wakeup_events = 1; > > + > > + pmu_fd = syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0); > > + if (CHECK_FAIL(pmu_fd < 0)) > > + goto cleanup; > > + > > + err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); > > + if (CHECK_FAIL(err)) > > + goto cleanup; > > + > > + err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); > > + if (CHECK_FAIL(err)) > > + goto cleanup; > > > All this attaching boilerplate is now obsolete as well, stick to > bpf_program__attach_tracepoint(). But even better, use RAW_TRACEPOINT. > > > + > > + /* trigger some syscalls */ > > + sleep(1); > > + key = 3; > > + err = bpf_map_lookup_elem(ns_data_map_fd, &key, &nspid); > > + if (CHECK_FAIL(err)) > > + goto cleanup; > > + > > + if (CHECK(id != nspid, "Compare user pid/tgid vs. bpf pid/tgid", > > + "Userspace pid/tgid %llu EBPF pid/tgid %llu\n", id, nspid)) > > + goto cleanup; > > + > > +cleanup: > > + close(pmu_fd); > > +close_prog: > > + bpf_object__close(obj); > > +} > > diff --git a/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c b/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c > > new file mode 100644 > > index 000000000000..3659aaa7c71f > > --- /dev/null > > +++ b/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c > > @@ -0,0 +1,53 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */ > > + > > +#include <linux/bpf.h> > > +#include "bpf_helpers.h" > > + > > +struct { > > + __uint(type, BPF_MAP_TYPE_ARRAY); > > + __uint(max_entries, 4); > > + __type(key, __u32); > > + __type(value, __u64); > > +} ns_data_map SEC(".maps"); > > + > > + > > +SEC("tracepoint/syscalls/sys_enter_nanosleep") > > +int trace(void *ctx) > > +{ > > + __u64 *val, *inum, *dev, nspidtgid, *expected_pid; > > + struct bpf_pidns_info nsdata; > > + __u32 key = 1; > > + > > + dev = bpf_map_lookup_elem(&ns_data_map, &key); > > + if (!dev) > > + return 0; > > + key = 2; > > + inum = bpf_map_lookup_elem(&ns_data_map, &key); > > + if (!inum) > > + return 0; > > + > > + nsdata.dev = *dev; > > + nsdata.inum = *inum; > > + > > + if (bpf_get_ns_current_pid_tgid(&nsdata, sizeof(struct bpf_pidns_info))) > > + return 0; > > + > > + nspidtgid = (__u64)nsdata.tgid << 32 | nsdata.pid; > > + key = 0; > > + expected_pid = bpf_map_lookup_elem(&ns_data_map, &key); > > + > > + if (!expected_pid || *expected_pid != nspidtgid) > > + return 0; > > + > > + key = 3; > > + val = bpf_map_lookup_elem(&ns_data_map, &key); > > Please, use global data for this, will make this BPF program much > shorter, cleaner, and up to the point. See recent patch by Daniel T. > Lee, or some of the tests I added (e.g., > progs/test_core_reloc_kernel.c) > > > + > > + if (val) > > + *val = nspidtgid; > > + > > + return 0; > > +} > > + > > +char _license[] SEC("license") = "GPL"; > > +__u32 _version SEC("version") = 1; > > You can drop version now (recent stuff), it's not required by libbpf anymore. > > > -- > > 2.20.1 > > Thanks for checking this out!, I'll rebase to current bpf-next and checkout progs/test_core_reloc_kernel.c. Bests
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index 54a50699bbfd..16261b23e011 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -233,6 +233,10 @@ static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal; static long long (*bpf_tcp_gen_syncookie)(struct bpf_sock *sk, void *ip, int ip_len, void *tcp, int tcp_len) = (void *) BPF_FUNC_tcp_gen_syncookie; +static unsigned long long (*bpf_get_ns_current_pid_tgid)(struct bpf_pidns_info *nsinfo, + unsigned int buf_size) = + (void *) BPF_FUNC_get_ns_current_pid_tgid; + /* llvm builtin functions that eBPF C program may use to * emit BPF_LD_ABS and BPF_LD_IND instructions diff --git a/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c b/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c new file mode 100644 index 000000000000..a7bff0ef6677 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c @@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */ +#include <test_progs.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <sys/syscall.h> + +void test_get_ns_current_pid_tgid(void) +{ + const char *probe_name = "syscalls/sys_enter_nanosleep"; + const char *file = "get_ns_current_pid_tgid_kern.o"; + int ns_data_map_fd, duration = 0; + struct perf_event_attr attr = {}; + int err, efd, prog_fd, pmu_fd; + __u64 ino, dev, id, nspid; + struct bpf_object *obj; + struct stat st; + __u32 key = 0; + 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)) + return; + + ns_data_map_fd = bpf_find_map(__func__, obj, "ns_data_map"); + if (CHECK_FAIL(ns_data_map_fd < 0)) + goto close_prog; + + pid_t tid = syscall(SYS_gettid); + pid_t pid = getpid(); + + id = (__u64) tid << 32 | pid; + bpf_map_update_elem(ns_data_map_fd, &key, &id, 0); + + if (stat("/proc/self/ns/pid", &st)) + goto close_prog; + + dev = st.st_dev; + ino = st.st_ino; + key = 1; + bpf_map_update_elem(ns_data_map_fd, &key, &dev, 0); + key = 2; + bpf_map_update_elem(ns_data_map_fd, &key, &ino, 0); + + snprintf(buf, sizeof(buf), + "/sys/kernel/debug/tracing/events/%s/id", probe_name); + efd = open(buf, O_RDONLY, 0); + read(efd, buf, sizeof(buf)); + close(efd); + attr.config = strtol(buf, NULL, 0); + attr.type = PERF_TYPE_TRACEPOINT; + attr.sample_type = PERF_SAMPLE_RAW; + attr.sample_period = 1; + attr.wakeup_events = 1; + + pmu_fd = syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0); + if (CHECK_FAIL(pmu_fd < 0)) + goto cleanup; + + err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); + if (CHECK_FAIL(err)) + goto cleanup; + + err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); + if (CHECK_FAIL(err)) + goto cleanup; + + /* trigger some syscalls */ + sleep(1); + key = 3; + err = bpf_map_lookup_elem(ns_data_map_fd, &key, &nspid); + if (CHECK_FAIL(err)) + goto cleanup; + + if (CHECK(id != nspid, "Compare user pid/tgid vs. bpf pid/tgid", + "Userspace pid/tgid %llu EBPF pid/tgid %llu\n", id, nspid)) + goto cleanup; + +cleanup: + close(pmu_fd); +close_prog: + bpf_object__close(obj); +} diff --git a/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c b/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c new file mode 100644 index 000000000000..3659aaa7c71f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Carlos Neira cneirabustos@gmail.com */ + +#include <linux/bpf.h> +#include "bpf_helpers.h" + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 4); + __type(key, __u32); + __type(value, __u64); +} ns_data_map SEC(".maps"); + + +SEC("tracepoint/syscalls/sys_enter_nanosleep") +int trace(void *ctx) +{ + __u64 *val, *inum, *dev, nspidtgid, *expected_pid; + struct bpf_pidns_info nsdata; + __u32 key = 1; + + dev = bpf_map_lookup_elem(&ns_data_map, &key); + if (!dev) + return 0; + key = 2; + inum = bpf_map_lookup_elem(&ns_data_map, &key); + if (!inum) + return 0; + + nsdata.dev = *dev; + nsdata.inum = *inum; + + if (bpf_get_ns_current_pid_tgid(&nsdata, sizeof(struct bpf_pidns_info))) + return 0; + + nspidtgid = (__u64)nsdata.tgid << 32 | nsdata.pid; + key = 0; + expected_pid = bpf_map_lookup_elem(&ns_data_map, &key); + + if (!expected_pid || *expected_pid != nspidtgid) + return 0; + + key = 3; + val = bpf_map_lookup_elem(&ns_data_map, &key); + + if (val) + *val = nspidtgid; + + return 0; +} + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = 1;
Self tests added for new helper Signed-off-by: Carlos Neira <cneirabustos@gmail.com> --- tools/testing/selftests/bpf/bpf_helpers.h | 4 + .../bpf/prog_tests/get_ns_current_pid_tgid.c | 85 +++++++++++++++++++ .../bpf/progs/get_ns_current_pid_tgid_kern.c | 53 ++++++++++++ 3 files changed, 142 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/get_ns_current_pid_tgid.c create mode 100644 tools/testing/selftests/bpf/progs/get_ns_current_pid_tgid_kern.c