| Message ID | 1642678950-19584-4-git-send-email-alan.maguire@oracle.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | libbpf: name-based u[ret]probe attach | expand |
On Thu, Jan 20, 2022 at 3:43 AM Alan Maguire <alan.maguire@oracle.com> wrote: > > add tests that verify attaching by name for local functions in > a program and library functions in a shared object succeed for > uprobe and uretprobes using new "func_name" option for > bpf_program__attach_uprobe_opts(). Also verify auto-attach > works where uprobe, path to binary and function name are > specified. > > Signed-off-by: Alan Maguire <alan.maguire@oracle.com> > --- > .../selftests/bpf/prog_tests/attach_probe.c | 114 ++++++++++++++++++--- > .../selftests/bpf/progs/test_attach_probe.c | 33 ++++++ > 2 files changed, 130 insertions(+), 17 deletions(-) > > diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c > index d0bd51e..1bfb09e 100644 > --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c > +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c > @@ -10,16 +10,24 @@ static void method(void) { > return ; > } > > +/* attach point for byname uprobe */ > +static void method2(void) > +{ > +} > + > void test_attach_probe(void) > { > DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts); > int duration = 0; > struct bpf_link *kprobe_link, *kretprobe_link; > - struct bpf_link *uprobe_link, *uretprobe_link; > + struct bpf_link *uprobe_link[3], *uretprobe_link[3]; why do you need an array, uprobe_link and uretprobe_link are just temporary variables for shorter code, those links are assigned into skel->links section and taken care of by skeleton destroy method > struct test_attach_probe* skel; > size_t uprobe_offset; > ssize_t base_addr, ref_ctr_offset; > + char libc_path[256]; > bool legacy; > + char *mem; > + FILE *f; > > /* Check if new-style kprobe/uprobe API is supported. > * Kernels that support new FD-based kprobe and uprobe BPF attachment > @@ -69,14 +77,14 @@ void test_attach_probe(void) > > uprobe_opts.retprobe = false; > uprobe_opts.ref_ctr_offset = legacy ? 0 : ref_ctr_offset; > - uprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, > - 0 /* self pid */, > - "/proc/self/exe", > - uprobe_offset, > - &uprobe_opts); > - if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe")) > + uprobe_link[0] = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, > + 0 /* self pid */, > + "/proc/self/exe", > + uprobe_offset, > + &uprobe_opts); > + if (!ASSERT_OK_PTR(uprobe_link[0], "attach_uprobe")) > goto cleanup; > - skel->links.handle_uprobe = uprobe_link; > + skel->links.handle_uprobe = uprobe_link[0]; > > if (!legacy) > ASSERT_GT(uprobe_ref_ctr, 0, "uprobe_ref_ctr_after"); > @@ -84,17 +92,79 @@ void test_attach_probe(void) > /* if uprobe uses ref_ctr, uretprobe has to use ref_ctr as well */ > uprobe_opts.retprobe = true; > uprobe_opts.ref_ctr_offset = legacy ? 0 : ref_ctr_offset; > - uretprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, > - -1 /* any pid */, > + uretprobe_link[0] = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, > + -1 /* any pid */, > + "/proc/self/exe", > + uprobe_offset, &uprobe_opts); > + if (!ASSERT_OK_PTR(uretprobe_link[0], "attach_uretprobe")) > + goto cleanup; > + skel->links.handle_uretprobe = uretprobe_link[0]; > + > + uprobe_opts.func_name = "method2"; > + uprobe_opts.retprobe = false; > + uprobe_opts.ref_ctr_offset = 0; > + uprobe_link[1] = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname, > + 0 /* this pid */, > "/proc/self/exe", > - uprobe_offset, &uprobe_opts); > - if (!ASSERT_OK_PTR(uretprobe_link, "attach_uretprobe")) > + 0, &uprobe_opts); > + if (!ASSERT_OK_PTR(uprobe_link[1], "attach_uprobe_byname")) > + goto cleanup; > + skel->links.handle_uprobe_byname = uprobe_link[1]; > + > + /* verify auto-attach works */ > + uretprobe_link[1] = bpf_program__attach(skel->progs.handle_uretprobe_byname); > + if (!ASSERT_OK_PTR(uretprobe_link[1], "attach_uretprobe_byname")) > + goto cleanup; > + skel->links.handle_uretprobe_byname = uretprobe_link[1]; > + > + /* test attach by name for a library function, using the library > + * as the binary argument. To do this, find path to libc used > + * by test_progs via /proc/self/maps. > + */ > + f = fopen("/proc/self/maps", "r"); > + if (!ASSERT_OK_PTR(f, "read /proc/self/maps")) > + goto cleanup; > + while (fscanf(f, "%*s %*s %*s %*s %*s %[^\n]", libc_path) == 1) { > + if (strstr(libc_path, "libc-")) > + break; > + } > + fclose(f); > + if (!ASSERT_NEQ(strstr(libc_path, "libc-"), NULL, "find libc path in /proc/self/maps")) > + goto cleanup; maybe let's extract this into a small helper, we'll eventually probably use it for other tests (and it just makes it a bit more obvious what's going on) > + > + uprobe_opts.func_name = "malloc"; > + uprobe_opts.retprobe = false; > + uprobe_link[2] = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname2, > + 0 /* this pid */, > + libc_path, > + 0, &uprobe_opts); > + if (!ASSERT_OK_PTR(uprobe_link[2], "attach_uprobe_byname2")) > goto cleanup; > - skel->links.handle_uretprobe = uretprobe_link; > + skel->links.handle_uprobe_byname2 = uprobe_link[2]; > > - /* trigger & validate kprobe && kretprobe */ > + uprobe_opts.func_name = "free"; > + uprobe_opts.retprobe = true; > + uretprobe_link[2] = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe_byname2, > + -1 /* any pid */, > + libc_path, > + 0, &uprobe_opts); > + if (!ASSERT_OK_PTR(uretprobe_link[2], "attach_uretprobe_byname2")) > + goto cleanup; > + skel->links.handle_uretprobe_byname2 = uretprobe_link[2]; > + > + /* trigger & validate kprobe && kretprobe && uretprobe by name */ > usleep(1); > > + /* trigger & validate shared library u[ret]probes attached by name */ > + mem = malloc(1); > + free(mem); > + > + /* trigger & validate uprobe & uretprobe */ > + method(); > + > + /* trigger & validate uprobe attached by name */ > + method2(); > + > if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res", > "wrong kprobe res: %d\n", skel->bss->kprobe_res)) > goto cleanup; > @@ -102,9 +172,6 @@ void test_attach_probe(void) > "wrong kretprobe res: %d\n", skel->bss->kretprobe_res)) > goto cleanup; > > - /* trigger & validate uprobe & uretprobe */ > - method(); > - > if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res", > "wrong uprobe res: %d\n", skel->bss->uprobe_res)) > goto cleanup; > @@ -112,6 +179,19 @@ void test_attach_probe(void) > "wrong uretprobe res: %d\n", skel->bss->uretprobe_res)) > goto cleanup; > > + if (CHECK(skel->bss->uprobe_byname_res != 5, "check_uprobe_byname_res", > + "wrong uprobe byname res: %d\n", skel->bss->uprobe_byname_res)) > + goto cleanup; > + if (CHECK(skel->bss->uretprobe_byname_res != 6, "check_uretprobe_byname_res", > + "wrong uretprobe byname res: %d\n", skel->bss->uretprobe_byname_res)) > + goto cleanup; > + if (CHECK(skel->bss->uprobe_byname2_res != 7, "check_uprobe_byname2_res", > + "wrong uprobe byname2 res: %d\n", skel->bss->uprobe_byname2_res)) > + goto cleanup; > + if (CHECK(skel->bss->uretprobe_byname2_res != 8, "check_uretprobe_byname2_res", > + "wrong uretprobe byname2 res: %d\n", skel->bss->uretprobe_byname2_res)) > + goto cleanup; use ASSERT_xxx() instead of CHECK() for new tests > + > cleanup: > test_attach_probe__destroy(skel); > ASSERT_EQ(uprobe_ref_ctr, 0, "uprobe_ref_ctr_cleanup"); > diff --git a/tools/testing/selftests/bpf/progs/test_attach_probe.c b/tools/testing/selftests/bpf/progs/test_attach_probe.c > index 8056a4c..c176c89 100644 > --- a/tools/testing/selftests/bpf/progs/test_attach_probe.c > +++ b/tools/testing/selftests/bpf/progs/test_attach_probe.c > @@ -10,6 +10,10 @@ > int kretprobe_res = 0; > int uprobe_res = 0; > int uretprobe_res = 0; > +int uprobe_byname_res = 0; > +int uretprobe_byname_res = 0; > +int uprobe_byname2_res = 0; > +int uretprobe_byname2_res = 0; > > SEC("kprobe/sys_nanosleep") > int handle_kprobe(struct pt_regs *ctx) > @@ -39,4 +43,33 @@ int handle_uretprobe(struct pt_regs *ctx) > return 0; > } > > +SEC("uprobe/trigger_func_byname") this should be just SEC("uprobe") ? > +int handle_uprobe_byname(struct pt_regs *ctx) > +{ > + uprobe_byname_res = 5; > + return 0; > +} > + > +/* use auto-attach format for section definition. */ > +SEC("uretprobe/proc/self/exe/method2") > +int handle_uretprobe_byname(struct pt_regs *ctx) > +{ > + uretprobe_byname_res = 6; > + return 0; > +} > + > +SEC("uprobe/trigger_func_byname2") > +int handle_uprobe_byname2(struct pt_regs *ctx) > +{ > + uprobe_byname2_res = 7; > + return 0; > +} > + > +SEC("uretprobe/trigger_func_byname2") same here and above, SEC("uprobe") if you don't specify binary + func. We should tighten this up for other SEC_DEF()s as well, but that's separate change from yours. > +int handle_uretprobe_byname2(struct pt_regs *ctx) > +{ > + uretprobe_byname2_res = 8; > + return 0; > +} > + > char _license[] SEC("license") = "GPL"; > -- > 1.8.3.1 >
diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c index d0bd51e..1bfb09e 100644 --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c @@ -10,16 +10,24 @@ static void method(void) { return ; } +/* attach point for byname uprobe */ +static void method2(void) +{ +} + void test_attach_probe(void) { DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts); int duration = 0; struct bpf_link *kprobe_link, *kretprobe_link; - struct bpf_link *uprobe_link, *uretprobe_link; + struct bpf_link *uprobe_link[3], *uretprobe_link[3]; struct test_attach_probe* skel; size_t uprobe_offset; ssize_t base_addr, ref_ctr_offset; + char libc_path[256]; bool legacy; + char *mem; + FILE *f; /* Check if new-style kprobe/uprobe API is supported. * Kernels that support new FD-based kprobe and uprobe BPF attachment @@ -69,14 +77,14 @@ void test_attach_probe(void) uprobe_opts.retprobe = false; uprobe_opts.ref_ctr_offset = legacy ? 0 : ref_ctr_offset; - uprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, - 0 /* self pid */, - "/proc/self/exe", - uprobe_offset, - &uprobe_opts); - if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe")) + uprobe_link[0] = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, + 0 /* self pid */, + "/proc/self/exe", + uprobe_offset, + &uprobe_opts); + if (!ASSERT_OK_PTR(uprobe_link[0], "attach_uprobe")) goto cleanup; - skel->links.handle_uprobe = uprobe_link; + skel->links.handle_uprobe = uprobe_link[0]; if (!legacy) ASSERT_GT(uprobe_ref_ctr, 0, "uprobe_ref_ctr_after"); @@ -84,17 +92,79 @@ void test_attach_probe(void) /* if uprobe uses ref_ctr, uretprobe has to use ref_ctr as well */ uprobe_opts.retprobe = true; uprobe_opts.ref_ctr_offset = legacy ? 0 : ref_ctr_offset; - uretprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, - -1 /* any pid */, + uretprobe_link[0] = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, + -1 /* any pid */, + "/proc/self/exe", + uprobe_offset, &uprobe_opts); + if (!ASSERT_OK_PTR(uretprobe_link[0], "attach_uretprobe")) + goto cleanup; + skel->links.handle_uretprobe = uretprobe_link[0]; + + uprobe_opts.func_name = "method2"; + uprobe_opts.retprobe = false; + uprobe_opts.ref_ctr_offset = 0; + uprobe_link[1] = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname, + 0 /* this pid */, "/proc/self/exe", - uprobe_offset, &uprobe_opts); - if (!ASSERT_OK_PTR(uretprobe_link, "attach_uretprobe")) + 0, &uprobe_opts); + if (!ASSERT_OK_PTR(uprobe_link[1], "attach_uprobe_byname")) + goto cleanup; + skel->links.handle_uprobe_byname = uprobe_link[1]; + + /* verify auto-attach works */ + uretprobe_link[1] = bpf_program__attach(skel->progs.handle_uretprobe_byname); + if (!ASSERT_OK_PTR(uretprobe_link[1], "attach_uretprobe_byname")) + goto cleanup; + skel->links.handle_uretprobe_byname = uretprobe_link[1]; + + /* test attach by name for a library function, using the library + * as the binary argument. To do this, find path to libc used + * by test_progs via /proc/self/maps. + */ + f = fopen("/proc/self/maps", "r"); + if (!ASSERT_OK_PTR(f, "read /proc/self/maps")) + goto cleanup; + while (fscanf(f, "%*s %*s %*s %*s %*s %[^\n]", libc_path) == 1) { + if (strstr(libc_path, "libc-")) + break; + } + fclose(f); + if (!ASSERT_NEQ(strstr(libc_path, "libc-"), NULL, "find libc path in /proc/self/maps")) + goto cleanup; + + uprobe_opts.func_name = "malloc"; + uprobe_opts.retprobe = false; + uprobe_link[2] = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname2, + 0 /* this pid */, + libc_path, + 0, &uprobe_opts); + if (!ASSERT_OK_PTR(uprobe_link[2], "attach_uprobe_byname2")) goto cleanup; - skel->links.handle_uretprobe = uretprobe_link; + skel->links.handle_uprobe_byname2 = uprobe_link[2]; - /* trigger & validate kprobe && kretprobe */ + uprobe_opts.func_name = "free"; + uprobe_opts.retprobe = true; + uretprobe_link[2] = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe_byname2, + -1 /* any pid */, + libc_path, + 0, &uprobe_opts); + if (!ASSERT_OK_PTR(uretprobe_link[2], "attach_uretprobe_byname2")) + goto cleanup; + skel->links.handle_uretprobe_byname2 = uretprobe_link[2]; + + /* trigger & validate kprobe && kretprobe && uretprobe by name */ usleep(1); + /* trigger & validate shared library u[ret]probes attached by name */ + mem = malloc(1); + free(mem); + + /* trigger & validate uprobe & uretprobe */ + method(); + + /* trigger & validate uprobe attached by name */ + method2(); + if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res", "wrong kprobe res: %d\n", skel->bss->kprobe_res)) goto cleanup; @@ -102,9 +172,6 @@ void test_attach_probe(void) "wrong kretprobe res: %d\n", skel->bss->kretprobe_res)) goto cleanup; - /* trigger & validate uprobe & uretprobe */ - method(); - if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res", "wrong uprobe res: %d\n", skel->bss->uprobe_res)) goto cleanup; @@ -112,6 +179,19 @@ void test_attach_probe(void) "wrong uretprobe res: %d\n", skel->bss->uretprobe_res)) goto cleanup; + if (CHECK(skel->bss->uprobe_byname_res != 5, "check_uprobe_byname_res", + "wrong uprobe byname res: %d\n", skel->bss->uprobe_byname_res)) + goto cleanup; + if (CHECK(skel->bss->uretprobe_byname_res != 6, "check_uretprobe_byname_res", + "wrong uretprobe byname res: %d\n", skel->bss->uretprobe_byname_res)) + goto cleanup; + if (CHECK(skel->bss->uprobe_byname2_res != 7, "check_uprobe_byname2_res", + "wrong uprobe byname2 res: %d\n", skel->bss->uprobe_byname2_res)) + goto cleanup; + if (CHECK(skel->bss->uretprobe_byname2_res != 8, "check_uretprobe_byname2_res", + "wrong uretprobe byname2 res: %d\n", skel->bss->uretprobe_byname2_res)) + goto cleanup; + cleanup: test_attach_probe__destroy(skel); ASSERT_EQ(uprobe_ref_ctr, 0, "uprobe_ref_ctr_cleanup"); diff --git a/tools/testing/selftests/bpf/progs/test_attach_probe.c b/tools/testing/selftests/bpf/progs/test_attach_probe.c index 8056a4c..c176c89 100644 --- a/tools/testing/selftests/bpf/progs/test_attach_probe.c +++ b/tools/testing/selftests/bpf/progs/test_attach_probe.c @@ -10,6 +10,10 @@ int kretprobe_res = 0; int uprobe_res = 0; int uretprobe_res = 0; +int uprobe_byname_res = 0; +int uretprobe_byname_res = 0; +int uprobe_byname2_res = 0; +int uretprobe_byname2_res = 0; SEC("kprobe/sys_nanosleep") int handle_kprobe(struct pt_regs *ctx) @@ -39,4 +43,33 @@ int handle_uretprobe(struct pt_regs *ctx) return 0; } +SEC("uprobe/trigger_func_byname") +int handle_uprobe_byname(struct pt_regs *ctx) +{ + uprobe_byname_res = 5; + return 0; +} + +/* use auto-attach format for section definition. */ +SEC("uretprobe/proc/self/exe/method2") +int handle_uretprobe_byname(struct pt_regs *ctx) +{ + uretprobe_byname_res = 6; + return 0; +} + +SEC("uprobe/trigger_func_byname2") +int handle_uprobe_byname2(struct pt_regs *ctx) +{ + uprobe_byname2_res = 7; + return 0; +} + +SEC("uretprobe/trigger_func_byname2") +int handle_uretprobe_byname2(struct pt_regs *ctx) +{ + uretprobe_byname2_res = 8; + return 0; +} + char _license[] SEC("license") = "GPL";
add tests that verify attaching by name for local functions in a program and library functions in a shared object succeed for uprobe and uretprobes using new "func_name" option for bpf_program__attach_uprobe_opts(). Also verify auto-attach works where uprobe, path to binary and function name are specified. Signed-off-by: Alan Maguire <alan.maguire@oracle.com> --- .../selftests/bpf/prog_tests/attach_probe.c | 114 ++++++++++++++++++--- .../selftests/bpf/progs/test_attach_probe.c | 33 ++++++ 2 files changed, 130 insertions(+), 17 deletions(-)