| Message ID | 20240729-convert_dev_cgroup-v2-2-4c1fc0520545@bootlin.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | selftests/bpf: convert test_dev_cgroup to test_progs | expand |
On 29/07/2024 09:20, Alexis Lothoré (eBPF Foundation) wrote: > test_dev_cgroup is defined as a standalone test program, and so is not > executed in CI. > > Convert it to test_progs framework so it is tested automatically in CI, and > remove the old test. In order to be able to run it in test_progs, /dev/null > must remain usable, so change the new test to test operations on devices > 1:3 as valid, and operations on devices 1:5 (/dev/zero) as invalid. > > Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com> A few small suggestions but looks great! Reviewed-by: Alan Maguire <alan.maguire@oracle.com> > --- > Changes in v2: > - pass expected return code to subtest function instead of boolean pass/not > pass > - also pass buffer and buffer size for read/write subtests > - fix faulty fd check on read/write tests expected to fail > --- > tools/testing/selftests/bpf/.gitignore | 1 - > tools/testing/selftests/bpf/Makefile | 2 - > .../testing/selftests/bpf/prog_tests/cgroup_dev.c | 110 +++++++++++++++++++++ > tools/testing/selftests/bpf/test_dev_cgroup.c | 85 ---------------- > 4 files changed, 110 insertions(+), 88 deletions(-) > > diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore > index 4e4aae8aa7ec..8f14d8faeb0b 100644 > --- a/tools/testing/selftests/bpf/.gitignore > +++ b/tools/testing/selftests/bpf/.gitignore > @@ -9,7 +9,6 @@ test_lpm_map > test_tag > FEATURE-DUMP.libbpf > fixdep > -test_dev_cgroup > /test_progs > /test_progs-no_alu32 > /test_progs-bpf_gcc > diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile > index aeada478e37a..2a9ba2246f80 100644 > --- a/tools/testing/selftests/bpf/Makefile > +++ b/tools/testing/selftests/bpf/Makefile > @@ -69,7 +69,6 @@ endif > > # Order correspond to 'make run_tests' order > TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ > - test_dev_cgroup \ > test_sock test_sockmap get_cgroup_id_user \ > test_cgroup_storage \ > test_tcpnotify_user test_sysctl \ > @@ -295,7 +294,6 @@ JSON_WRITER := $(OUTPUT)/json_writer.o > CAP_HELPERS := $(OUTPUT)/cap_helpers.o > NETWORK_HELPERS := $(OUTPUT)/network_helpers.o > > -$(OUTPUT)/test_dev_cgroup: $(CGROUP_HELPERS) $(TESTING_HELPERS) > $(OUTPUT)/test_skb_cgroup_id_user: $(CGROUP_HELPERS) $(TESTING_HELPERS) > $(OUTPUT)/test_sock: $(CGROUP_HELPERS) $(TESTING_HELPERS) > $(OUTPUT)/test_sockmap: $(CGROUP_HELPERS) $(TESTING_HELPERS) > diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_dev.c b/tools/testing/selftests/bpf/prog_tests/cgroup_dev.c > new file mode 100644 > index 000000000000..af0b70086c21 > --- /dev/null > +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_dev.c > @@ -0,0 +1,110 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <sys/stat.h> > +#include <sys/sysmacros.h> > +#include "test_progs.h" > +#include "cgroup_helpers.h" > +#include "dev_cgroup.skel.h" > + > +#define TEST_CGROUP "/test-bpf-based-device-cgroup/" > +#define TEST_BUFFER_SIZE 64 > + > +static void test_mknod(const char *path, mode_t mode, int dev_major, > + int dev_minor, int expected_ret) > +{ > + int ret; > + > + unlink(path); > + ret = mknod(path, mode, makedev(dev_major, dev_minor)); > + ASSERT_EQ(ret, expected_ret, "mknod"); no need to unlink unless "if (!ret)" > + unlink(path); > +} > + > +static void test_read(const char *path, char *buf, int buf_size, int expected_ret) > +{ > + int ret, fd; > + > + fd = open(path, O_RDONLY); > + > + /* A bare open on unauthorized device should fail */ > + if (expected_ret < 0) { > + ASSERT_EQ(fd, expected_ret, "open file for read"); > + if (fd >= 0) > + close(fd); > + return; > + } > + > + if (!ASSERT_OK_FD(fd, "open file for read")) > + return; > + > + ret = read(fd, buf, buf_size); > + ASSERT_EQ(ret, expected_ret, "read"); > + > + close(fd); > +} > + > +static void test_write(const char *path, char *buf, int buf_size, int expected_ret) > +{ > + int ret, fd; > + > + fd = open(path, O_WRONLY); > + > + /* A bare open on unauthorized device should fail */ > + if (expected_ret < 0) { > + ASSERT_EQ(fd, expected_ret, "open file for write"); > + if (fd >= 0) > + close(fd); > + return; > + } > + > + if (!ASSERT_OK_FD(fd, "open file for write")) > + return; > + > + ret = write(fd, buf, buf_size); > + ASSERT_EQ(ret, expected_ret, "write"); > + > + close(fd); > +} > + > +void test_cgroup_dev(void) > +{ > + char buf[TEST_BUFFER_SIZE] = "some random test data"; > + struct dev_cgroup *skel; > + int cgroup_fd; > + > + cgroup_fd = cgroup_setup_and_join(TEST_CGROUP); > + if (!ASSERT_OK_FD(cgroup_fd, "cgroup switch")) > + return; > + > + skel = dev_cgroup__open_and_load(); > + if (!ASSERT_OK_PTR(skel, "load program")) > + goto cleanup_cgroup; > + > + if (!ASSERT_OK(bpf_prog_attach(bpf_program__fd(skel->progs.bpf_prog1), > + cgroup_fd, BPF_CGROUP_DEVICE, 0), > + "attach_program")) I'd suggest using bpf_program__attach_cgroup() here as you can assign the link in the skeleton; see prog_tests/cgroup_v1v2.c. > + goto cleanup_progs; > + > + if (test__start_subtest("deny-mknod")) > + test_mknod("/dev/test_dev_cgroup_zero", S_IFCHR, 1, 5, -EPERM); > + nit: group with other deny subtests. > + if (test__start_subtest("allow-mknod")) > + test_mknod("/dev/test_dev_cgroup_null", S_IFCHR, 1, 3, 0); > + > + if (test__start_subtest("allow-read")) > + test_read("/dev/urandom", buf, TEST_BUFFER_SIZE, TEST_BUFFER_SIZE); > + Nit: should we have a separate garbage buffer for the successful /dev/urandom read? We're not validating buffer contents anywhere but we will overwrite our test string I think and it'll end up non-null terminated. Alan
Hello Alan, thanks for the review On 7/29/24 19:29, Alan Maguire wrote: > On 29/07/2024 09:20, Alexis Lothoré (eBPF Foundation) wrote: >> test_dev_cgroup is defined as a standalone test program, and so is not >> executed in CI. >> >> Convert it to test_progs framework so it is tested automatically in CI, and >> remove the old test. In order to be able to run it in test_progs, /dev/null >> must remain usable, so change the new test to test operations on devices >> 1:3 as valid, and operations on devices 1:5 (/dev/zero) as invalid. >> >> Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com> > > A few small suggestions but looks great! > > Reviewed-by: Alan Maguire <alan.maguire@oracle.com> [...] >> + unlink(path); >> + ret = mknod(path, mode, makedev(dev_major, dev_minor)); >> + ASSERT_EQ(ret, expected_ret, "mknod"); > no need to unlink unless "if (!ret)" Indeed, you are right. [...] >> + skel = dev_cgroup__open_and_load(); >> + if (!ASSERT_OK_PTR(skel, "load program")) >> + goto cleanup_cgroup; >> + >> + if (!ASSERT_OK(bpf_prog_attach(bpf_program__fd(skel->progs.bpf_prog1), >> + cgroup_fd, BPF_CGROUP_DEVICE, 0), >> + "attach_program")) > > I'd suggest using bpf_program__attach_cgroup() here as you can assign > the link in the skeleton; see prog_tests/cgroup_v1v2.c. Ah yes, thanks for the hint ! >> + goto cleanup_progs; >> + >> + if (test__start_subtest("deny-mknod")) >> + test_mknod("/dev/test_dev_cgroup_zero", S_IFCHR, 1, 5, -EPERM); >> + > > nit: group with other deny subtests. ACK >> + if (test__start_subtest("allow-mknod")) >> + test_mknod("/dev/test_dev_cgroup_null", S_IFCHR, 1, 3, 0); >> + >> + if (test__start_subtest("allow-read")) >> + test_read("/dev/urandom", buf, TEST_BUFFER_SIZE, TEST_BUFFER_SIZE); >> + > > Nit: should we have a separate garbage buffer for the successful > /dev/urandom read? We're not validating buffer contents anywhere but we > will overwrite our test string I think and it'll end up non-null terminated. True, but since the tests aren't performing any string operation on it, is it really a big deal ? I can even switch the string to a byte array, if it can prevent any mistake. If that's ok for you, I can bring all the suggestions discussed here in a new revision and keep your review tag. Thanks, Alexis > > Alan
On 29/07/2024 18:47, Alexis Lothoré wrote: > Hello Alan, thanks for the review > > On 7/29/24 19:29, Alan Maguire wrote: >> On 29/07/2024 09:20, Alexis Lothoré (eBPF Foundation) wrote: >>> test_dev_cgroup is defined as a standalone test program, and so is not >>> executed in CI. >>> >>> Convert it to test_progs framework so it is tested automatically in CI, and >>> remove the old test. In order to be able to run it in test_progs, /dev/null >>> must remain usable, so change the new test to test operations on devices >>> 1:3 as valid, and operations on devices 1:5 (/dev/zero) as invalid. >>> >>> Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com> >> >> A few small suggestions but looks great! >> >> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> > > [...] > >>> + unlink(path); >>> + ret = mknod(path, mode, makedev(dev_major, dev_minor)); >>> + ASSERT_EQ(ret, expected_ret, "mknod"); >> no need to unlink unless "if (!ret)" > > Indeed, you are right. > > [...] > >>> + skel = dev_cgroup__open_and_load(); >>> + if (!ASSERT_OK_PTR(skel, "load program")) >>> + goto cleanup_cgroup; >>> + >>> + if (!ASSERT_OK(bpf_prog_attach(bpf_program__fd(skel->progs.bpf_prog1), >>> + cgroup_fd, BPF_CGROUP_DEVICE, 0), >>> + "attach_program")) >> >> I'd suggest using bpf_program__attach_cgroup() here as you can assign >> the link in the skeleton; see prog_tests/cgroup_v1v2.c. > > Ah yes, thanks for the hint ! > > >>> + goto cleanup_progs; >>> + >>> + if (test__start_subtest("deny-mknod")) >>> + test_mknod("/dev/test_dev_cgroup_zero", S_IFCHR, 1, 5, -EPERM); >>> + >> >> nit: group with other deny subtests. > > ACK > >>> + if (test__start_subtest("allow-mknod")) >>> + test_mknod("/dev/test_dev_cgroup_null", S_IFCHR, 1, 3, 0); >>> + >>> + if (test__start_subtest("allow-read")) >>> + test_read("/dev/urandom", buf, TEST_BUFFER_SIZE, TEST_BUFFER_SIZE); >>> + >> >> Nit: should we have a separate garbage buffer for the successful >> /dev/urandom read? We're not validating buffer contents anywhere but we >> will overwrite our test string I think and it'll end up non-null terminated. > > True, but since the tests aren't performing any string operation on it, is it > really a big deal ? I can even switch the string to a byte array, if it can > prevent any mistake. > There's no need, don't worry. As long as the size limits ensure we don't overrun the buffer, we're good. > If that's ok for you, I can bring all the suggestions discussed here in a new > revision and keep your review tag. > Sounds great, thanks! Alan
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index 4e4aae8aa7ec..8f14d8faeb0b 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -9,7 +9,6 @@ test_lpm_map test_tag FEATURE-DUMP.libbpf fixdep -test_dev_cgroup /test_progs /test_progs-no_alu32 /test_progs-bpf_gcc diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index aeada478e37a..2a9ba2246f80 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -69,7 +69,6 @@ endif # Order correspond to 'make run_tests' order TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ - test_dev_cgroup \ test_sock test_sockmap get_cgroup_id_user \ test_cgroup_storage \ test_tcpnotify_user test_sysctl \ @@ -295,7 +294,6 @@ JSON_WRITER := $(OUTPUT)/json_writer.o CAP_HELPERS := $(OUTPUT)/cap_helpers.o NETWORK_HELPERS := $(OUTPUT)/network_helpers.o -$(OUTPUT)/test_dev_cgroup: $(CGROUP_HELPERS) $(TESTING_HELPERS) $(OUTPUT)/test_skb_cgroup_id_user: $(CGROUP_HELPERS) $(TESTING_HELPERS) $(OUTPUT)/test_sock: $(CGROUP_HELPERS) $(TESTING_HELPERS) $(OUTPUT)/test_sockmap: $(CGROUP_HELPERS) $(TESTING_HELPERS) diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_dev.c b/tools/testing/selftests/bpf/prog_tests/cgroup_dev.c new file mode 100644 index 000000000000..af0b70086c21 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_dev.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <sys/stat.h> +#include <sys/sysmacros.h> +#include "test_progs.h" +#include "cgroup_helpers.h" +#include "dev_cgroup.skel.h" + +#define TEST_CGROUP "/test-bpf-based-device-cgroup/" +#define TEST_BUFFER_SIZE 64 + +static void test_mknod(const char *path, mode_t mode, int dev_major, + int dev_minor, int expected_ret) +{ + int ret; + + unlink(path); + ret = mknod(path, mode, makedev(dev_major, dev_minor)); + ASSERT_EQ(ret, expected_ret, "mknod"); + unlink(path); +} + +static void test_read(const char *path, char *buf, int buf_size, int expected_ret) +{ + int ret, fd; + + fd = open(path, O_RDONLY); + + /* A bare open on unauthorized device should fail */ + if (expected_ret < 0) { + ASSERT_EQ(fd, expected_ret, "open file for read"); + if (fd >= 0) + close(fd); + return; + } + + if (!ASSERT_OK_FD(fd, "open file for read")) + return; + + ret = read(fd, buf, buf_size); + ASSERT_EQ(ret, expected_ret, "read"); + + close(fd); +} + +static void test_write(const char *path, char *buf, int buf_size, int expected_ret) +{ + int ret, fd; + + fd = open(path, O_WRONLY); + + /* A bare open on unauthorized device should fail */ + if (expected_ret < 0) { + ASSERT_EQ(fd, expected_ret, "open file for write"); + if (fd >= 0) + close(fd); + return; + } + + if (!ASSERT_OK_FD(fd, "open file for write")) + return; + + ret = write(fd, buf, buf_size); + ASSERT_EQ(ret, expected_ret, "write"); + + close(fd); +} + +void test_cgroup_dev(void) +{ + char buf[TEST_BUFFER_SIZE] = "some random test data"; + struct dev_cgroup *skel; + int cgroup_fd; + + cgroup_fd = cgroup_setup_and_join(TEST_CGROUP); + if (!ASSERT_OK_FD(cgroup_fd, "cgroup switch")) + return; + + skel = dev_cgroup__open_and_load(); + if (!ASSERT_OK_PTR(skel, "load program")) + goto cleanup_cgroup; + + if (!ASSERT_OK(bpf_prog_attach(bpf_program__fd(skel->progs.bpf_prog1), + cgroup_fd, BPF_CGROUP_DEVICE, 0), + "attach_program")) + goto cleanup_progs; + + if (test__start_subtest("deny-mknod")) + test_mknod("/dev/test_dev_cgroup_zero", S_IFCHR, 1, 5, -EPERM); + + if (test__start_subtest("allow-mknod")) + test_mknod("/dev/test_dev_cgroup_null", S_IFCHR, 1, 3, 0); + + if (test__start_subtest("allow-read")) + test_read("/dev/urandom", buf, TEST_BUFFER_SIZE, TEST_BUFFER_SIZE); + + if (test__start_subtest("allow-write")) + test_write("/dev/null", buf, TEST_BUFFER_SIZE, TEST_BUFFER_SIZE); + + if (test__start_subtest("deny-read")) + test_read("/dev/random", buf, TEST_BUFFER_SIZE, -EPERM); + + if (test__start_subtest("deny-write")) + test_write("/dev/zero", buf, TEST_BUFFER_SIZE, -EPERM); + +cleanup_progs: + dev_cgroup__destroy(skel); +cleanup_cgroup: + cleanup_cgroup_environment(); +} diff --git a/tools/testing/selftests/bpf/test_dev_cgroup.c b/tools/testing/selftests/bpf/test_dev_cgroup.c deleted file mode 100644 index 33f544f0005a..000000000000 --- a/tools/testing/selftests/bpf/test_dev_cgroup.c +++ /dev/null @@ -1,85 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* Copyright (c) 2017 Facebook - */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <errno.h> -#include <assert.h> -#include <sys/time.h> - -#include <linux/bpf.h> -#include <bpf/bpf.h> -#include <bpf/libbpf.h> - -#include "cgroup_helpers.h" -#include "testing_helpers.h" - -#define DEV_CGROUP_PROG "./dev_cgroup.bpf.o" - -#define TEST_CGROUP "/test-bpf-based-device-cgroup/" - -int main(int argc, char **argv) -{ - struct bpf_object *obj; - int error = EXIT_FAILURE; - int prog_fd, cgroup_fd; - __u32 prog_cnt; - - /* Use libbpf 1.0 API mode */ - libbpf_set_strict_mode(LIBBPF_STRICT_ALL); - - if (bpf_prog_test_load(DEV_CGROUP_PROG, BPF_PROG_TYPE_CGROUP_DEVICE, - &obj, &prog_fd)) { - printf("Failed to load DEV_CGROUP program\n"); - goto out; - } - - cgroup_fd = cgroup_setup_and_join(TEST_CGROUP); - if (cgroup_fd < 0) { - printf("Failed to create test cgroup\n"); - goto out; - } - - /* Attach bpf program */ - if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_DEVICE, 0)) { - printf("Failed to attach DEV_CGROUP program"); - goto err; - } - - if (bpf_prog_query(cgroup_fd, BPF_CGROUP_DEVICE, 0, NULL, NULL, - &prog_cnt)) { - printf("Failed to query attached programs"); - goto err; - } - - /* All operations with /dev/null and /dev/urandom are allowed, - * everything else is forbidden. - */ - assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0); - assert(system("mknod /tmp/test_dev_cgroup_zero c 1 5")); - assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0); - - /* /dev/null is whitelisted */ - assert(system("rm -f /tmp/test_dev_cgroup_null") == 0); - assert(system("mknod /tmp/test_dev_cgroup_null c 1 3") == 0); - assert(system("rm -f /tmp/test_dev_cgroup_null") == 0); - - assert(system("dd if=/dev/urandom of=/dev/null count=64") == 0); - - /* src is allowed, target is forbidden */ - assert(system("dd if=/dev/urandom of=/dev/full count=64")); - - /* src is forbidden, target is allowed */ - assert(system("dd if=/dev/random of=/dev/null count=64")); - - error = 0; - printf("test_dev_cgroup:PASS\n"); - -err: - cleanup_cgroup_environment(); - -out: - return error; -}
test_dev_cgroup is defined as a standalone test program, and so is not executed in CI. Convert it to test_progs framework so it is tested automatically in CI, and remove the old test. In order to be able to run it in test_progs, /dev/null must remain usable, so change the new test to test operations on devices 1:3 as valid, and operations on devices 1:5 (/dev/zero) as invalid. Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com> --- Changes in v2: - pass expected return code to subtest function instead of boolean pass/not pass - also pass buffer and buffer size for read/write subtests - fix faulty fd check on read/write tests expected to fail --- tools/testing/selftests/bpf/.gitignore | 1 - tools/testing/selftests/bpf/Makefile | 2 - .../testing/selftests/bpf/prog_tests/cgroup_dev.c | 110 +++++++++++++++++++++ tools/testing/selftests/bpf/test_dev_cgroup.c | 85 ---------------- 4 files changed, 110 insertions(+), 88 deletions(-)