Message ID | 20200616100512.2168860-12-jolsa@kernel.org |
---|---|
State | Changes Requested |
Delegated to: | BPF Maintainers |
Headers | show |
Series | bpf: Add d_path helper | expand |
On Tue, Jun 16, 2020 at 3:07 AM Jiri Olsa <jolsa@kernel.org> wrote: > > Adding test for d_path helper which is pretty much > copied from Wenbo Zhang's test for bpf_get_fd_path, > which never made it in. > > I've failed so far to compile the test with <linux/fs.h> > kernel header, so for now adding 'struct file' with f_path > member that has same offset as kernel's file object. > > Original-patch-by: Wenbo Zhang <ethercflow@gmail.com> > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > --- > .../testing/selftests/bpf/prog_tests/d_path.c | 153 ++++++++++++++++++ > .../testing/selftests/bpf/progs/test_d_path.c | 55 +++++++ > 2 files changed, 208 insertions(+) > create mode 100644 tools/testing/selftests/bpf/prog_tests/d_path.c > create mode 100644 tools/testing/selftests/bpf/progs/test_d_path.c > > diff --git a/tools/testing/selftests/bpf/prog_tests/d_path.c b/tools/testing/selftests/bpf/prog_tests/d_path.c > new file mode 100644 > index 000000000000..e2b7dfeb506f > --- /dev/null > +++ b/tools/testing/selftests/bpf/prog_tests/d_path.c > @@ -0,0 +1,153 @@ > +// SPDX-License-Identifier: GPL-2.0 > +#define _GNU_SOURCE > +#include <test_progs.h> > +#include <sys/stat.h> > +#include <linux/sched.h> > +#include <sys/syscall.h> > + > +#define MAX_PATH_LEN 128 > +#define MAX_FILES 7 > +#define MAX_EVENT_NUM 16 > + > +struct d_path_test_data { > + pid_t pid; > + __u32 cnt_stat; > + __u32 cnt_close; > + char paths_stat[MAX_EVENT_NUM][MAX_PATH_LEN]; > + char paths_close[MAX_EVENT_NUM][MAX_PATH_LEN]; > +}; with skeleton there is no point in defining this container struct, and especially duplicating it between BPF code and user-space code. Just declare all those fields as global variables and access them from skeleton directly. [...] > diff --git a/tools/testing/selftests/bpf/progs/test_d_path.c b/tools/testing/selftests/bpf/progs/test_d_path.c > new file mode 100644 > index 000000000000..1b478c00ee7a > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/test_d_path.c > @@ -0,0 +1,55 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include "vmlinux.h" > +#include <bpf/bpf_helpers.h> > +#include <bpf/bpf_tracing.h> > + > +#define MAX_PATH_LEN 128 > +#define MAX_EVENT_NUM 16 > + > +static struct d_path_test_data { > + pid_t pid; > + __u32 cnt_stat; > + __u32 cnt_close; > + char paths_stat[MAX_EVENT_NUM][MAX_PATH_LEN]; > + char paths_close[MAX_EVENT_NUM][MAX_PATH_LEN]; > +} data; > + > +struct path; > +struct kstat; both structs are in vmlinux.h, you shouldn't need this. [...] >
On Thu, Jun 18, 2020 at 09:44:23PM -0700, Andrii Nakryiko wrote: > On Tue, Jun 16, 2020 at 3:07 AM Jiri Olsa <jolsa@kernel.org> wrote: > > > > Adding test for d_path helper which is pretty much > > copied from Wenbo Zhang's test for bpf_get_fd_path, > > which never made it in. > > > > I've failed so far to compile the test with <linux/fs.h> > > kernel header, so for now adding 'struct file' with f_path > > member that has same offset as kernel's file object. > > > > Original-patch-by: Wenbo Zhang <ethercflow@gmail.com> > > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > > --- > > .../testing/selftests/bpf/prog_tests/d_path.c | 153 ++++++++++++++++++ > > .../testing/selftests/bpf/progs/test_d_path.c | 55 +++++++ > > 2 files changed, 208 insertions(+) > > create mode 100644 tools/testing/selftests/bpf/prog_tests/d_path.c > > create mode 100644 tools/testing/selftests/bpf/progs/test_d_path.c > > > > diff --git a/tools/testing/selftests/bpf/prog_tests/d_path.c b/tools/testing/selftests/bpf/prog_tests/d_path.c > > new file mode 100644 > > index 000000000000..e2b7dfeb506f > > --- /dev/null > > +++ b/tools/testing/selftests/bpf/prog_tests/d_path.c > > @@ -0,0 +1,153 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +#define _GNU_SOURCE > > +#include <test_progs.h> > > +#include <sys/stat.h> > > +#include <linux/sched.h> > > +#include <sys/syscall.h> > > + > > +#define MAX_PATH_LEN 128 > > +#define MAX_FILES 7 > > +#define MAX_EVENT_NUM 16 > > + > > +struct d_path_test_data { > > + pid_t pid; > > + __u32 cnt_stat; > > + __u32 cnt_close; > > + char paths_stat[MAX_EVENT_NUM][MAX_PATH_LEN]; > > + char paths_close[MAX_EVENT_NUM][MAX_PATH_LEN]; > > +}; > > with skeleton there is no point in defining this container struct, and > especially duplicating it between BPF code and user-space code. Just > declare all those fields as global variables and access them from > skeleton directly. ok, will check > > [...] > > > diff --git a/tools/testing/selftests/bpf/progs/test_d_path.c b/tools/testing/selftests/bpf/progs/test_d_path.c > > new file mode 100644 > > index 000000000000..1b478c00ee7a > > --- /dev/null > > +++ b/tools/testing/selftests/bpf/progs/test_d_path.c > > @@ -0,0 +1,55 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > + > > +#include "vmlinux.h" > > +#include <bpf/bpf_helpers.h> > > +#include <bpf/bpf_tracing.h> > > + > > +#define MAX_PATH_LEN 128 > > +#define MAX_EVENT_NUM 16 > > + > > +static struct d_path_test_data { > > + pid_t pid; > > + __u32 cnt_stat; > > + __u32 cnt_close; > > + char paths_stat[MAX_EVENT_NUM][MAX_PATH_LEN]; > > + char paths_close[MAX_EVENT_NUM][MAX_PATH_LEN]; > > +} data; > > + > > +struct path; > > +struct kstat; > > both structs are in vmlinux.h, you shouldn't need this. leftover from earlier version, will remove thanks, jirka
diff --git a/tools/testing/selftests/bpf/prog_tests/d_path.c b/tools/testing/selftests/bpf/prog_tests/d_path.c new file mode 100644 index 000000000000..e2b7dfeb506f --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/d_path.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <test_progs.h> +#include <sys/stat.h> +#include <linux/sched.h> +#include <sys/syscall.h> + +#define MAX_PATH_LEN 128 +#define MAX_FILES 7 +#define MAX_EVENT_NUM 16 + +struct d_path_test_data { + pid_t pid; + __u32 cnt_stat; + __u32 cnt_close; + char paths_stat[MAX_EVENT_NUM][MAX_PATH_LEN]; + char paths_close[MAX_EVENT_NUM][MAX_PATH_LEN]; +}; + +#include "test_d_path.skel.h" + +static struct { + __u32 cnt; + char paths[MAX_EVENT_NUM][MAX_PATH_LEN]; +} src; + +static int set_pathname(int fd, pid_t pid) +{ + char buf[MAX_PATH_LEN]; + + snprintf(buf, MAX_PATH_LEN, "/proc/%d/fd/%d", pid, fd); + return readlink(buf, src.paths[src.cnt++], MAX_PATH_LEN); +} + +static int trigger_fstat_events(pid_t pid) +{ + int sockfd = -1, procfd = -1, devfd = -1; + int localfd = -1, indicatorfd = -1; + int pipefd[2] = { -1, -1 }; + struct stat fileStat; + int ret = -1; + + /* unmountable pseudo-filesystems */ + if (CHECK_FAIL(pipe(pipefd) < 0)) + return ret; + /* unmountable pseudo-filesystems */ + sockfd = socket(AF_INET, SOCK_STREAM, 0); + if (CHECK_FAIL(sockfd < 0)) + goto out_close; + /* mountable pseudo-filesystems */ + procfd = open("/proc/self/comm", O_RDONLY); + if (CHECK_FAIL(procfd < 0)) + goto out_close; + devfd = open("/dev/urandom", O_RDONLY); + if (CHECK_FAIL(devfd < 0)) + goto out_close; + localfd = open("/tmp/d_path_loadgen.txt", O_CREAT | O_RDONLY); + if (CHECK_FAIL(localfd < 0)) + goto out_close; + /* bpf_d_path will return path with (deleted) */ + remove("/tmp/d_path_loadgen.txt"); + indicatorfd = open("/tmp/", O_PATH); + if (CHECK_FAIL(indicatorfd < 0)) + goto out_close; + + ret = set_pathname(pipefd[0], pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + ret = set_pathname(pipefd[1], pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + ret = set_pathname(sockfd, pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + ret = set_pathname(procfd, pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + ret = set_pathname(devfd, pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + ret = set_pathname(localfd, pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + ret = set_pathname(indicatorfd, pid); + if (CHECK_FAIL(ret < 0)) + goto out_close; + + /* triggers vfs_getattr */ + fstat(pipefd[0], &fileStat); + fstat(pipefd[1], &fileStat); + fstat(sockfd, &fileStat); + fstat(procfd, &fileStat); + fstat(devfd, &fileStat); + fstat(localfd, &fileStat); + fstat(indicatorfd, &fileStat); + +out_close: + /* triggers filp_close */ + close(pipefd[0]); + close(pipefd[1]); + close(sockfd); + close(procfd); + close(devfd); + close(localfd); + close(indicatorfd); + return ret; +} + +void test_d_path(void) +{ + struct test_d_path *skel; + struct d_path_test_data *dst; + __u32 duration = 0; + int err; + + skel = test_d_path__open_and_load(); + if (CHECK(!skel, "test_d_path_load", "d_path skeleton failed\n")) + goto cleanup; + + err = test_d_path__attach(skel); + if (CHECK(err, "modify_return", "attach failed: %d\n", err)) + goto cleanup; + + dst = &skel->bss->data; + dst->pid = getpid(); + + err = trigger_fstat_events(skel->bss->data.pid); + if (CHECK_FAIL(err < 0)) + goto cleanup; + + for (int i = 0; i < MAX_FILES; i++) { + if (i < 3) { + CHECK((dst->paths_stat[i][0] == 0), "d_path", + "failed to filter fs [%d]: %s vs %s\n", + i, src.paths[i], dst->paths_stat[i]); + CHECK((dst->paths_close[i][0] == 0), "d_path", + "failed to filter fs [%d]: %s vs %s\n", + i, src.paths[i], dst->paths_close[i]); + } else { + CHECK(strncmp(src.paths[i], dst->paths_stat[i], MAX_PATH_LEN), + "d_path", + "failed to get stat path[%d]: %s vs %s\n", + i, src.paths[i], dst->paths_stat[i]); + CHECK(strncmp(src.paths[i], dst->paths_close[i], MAX_PATH_LEN), + "d_path", + "failed to get close path[%d]: %s vs %s\n", + i, src.paths[i], dst->paths_close[i]); + } + } + +cleanup: + test_d_path__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_d_path.c b/tools/testing/selftests/bpf/progs/test_d_path.c new file mode 100644 index 000000000000..1b478c00ee7a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_d_path.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +#define MAX_PATH_LEN 128 +#define MAX_EVENT_NUM 16 + +static struct d_path_test_data { + pid_t pid; + __u32 cnt_stat; + __u32 cnt_close; + char paths_stat[MAX_EVENT_NUM][MAX_PATH_LEN]; + char paths_close[MAX_EVENT_NUM][MAX_PATH_LEN]; +} data; + +struct path; +struct kstat; + +SEC("fentry/vfs_getattr") +int BPF_PROG(prog_stat, struct path *path, struct kstat *stat, + __u32 request_mask, unsigned int query_flags) +{ + pid_t pid = bpf_get_current_pid_tgid() >> 32; + + if (pid != data.pid) + return 0; + + if (data.cnt_stat >= MAX_EVENT_NUM) + return 0; + + bpf_d_path(path, data.paths_stat[data.cnt_stat], MAX_PATH_LEN); + data.cnt_stat++; + return 0; +} + +SEC("fentry/filp_close") +int BPF_PROG(prog_close, struct file *file, void *id) +{ + pid_t pid = bpf_get_current_pid_tgid() >> 32; + + if (pid != data.pid) + return 0; + + if (data.cnt_close >= MAX_EVENT_NUM) + return 0; + + bpf_d_path((struct path *) &file->f_path, + data.paths_close[data.cnt_close], MAX_PATH_LEN); + data.cnt_close++; + return 0; +} + +char _license[] SEC("license") = "GPL";
Adding test for d_path helper which is pretty much copied from Wenbo Zhang's test for bpf_get_fd_path, which never made it in. I've failed so far to compile the test with <linux/fs.h> kernel header, so for now adding 'struct file' with f_path member that has same offset as kernel's file object. Original-patch-by: Wenbo Zhang <ethercflow@gmail.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- .../testing/selftests/bpf/prog_tests/d_path.c | 153 ++++++++++++++++++ .../testing/selftests/bpf/progs/test_d_path.c | 55 +++++++ 2 files changed, 208 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/d_path.c create mode 100644 tools/testing/selftests/bpf/progs/test_d_path.c