| Message ID | 20230428071737.43849-3-zhoufeng.zf@bytedance.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Introduce a new kfunc of bpf_task_under_cgroup | expand |
On 4/28/23 12:17 AM, Feng zhou wrote: > From: Feng Zhou <zhoufeng.zf@bytedance.com> > > test_progs: > Tests new kfunc bpf_task_under_cgroup(). > > The bpf program saves the new task's pid within a given cgroup to > the remote_pid, which is convenient for the user-mode program to > verify the test correctness. > > The user-mode program creates its own mount namespace, and mounts the > cgroupsv2 hierarchy in there, call the fork syscall, then check if > remote_pid and local_pid are unequal. > > Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com> Ack with a few nits below. Acked-by: Yonghong Song <yhs@fb.com> > --- > tools/testing/selftests/bpf/DENYLIST.s390x | 1 + > .../bpf/prog_tests/task_under_cgroup.c | 55 +++++++++++++++++++ > .../bpf/progs/test_task_under_cgroup.c | 51 +++++++++++++++++ > 3 files changed, 107 insertions(+) > create mode 100644 tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c > create mode 100644 tools/testing/selftests/bpf/progs/test_task_under_cgroup.c > > diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x b/tools/testing/selftests/bpf/DENYLIST.s390x > index c7463f3ec3c0..5061d9e24c16 100644 > --- a/tools/testing/selftests/bpf/DENYLIST.s390x > +++ b/tools/testing/selftests/bpf/DENYLIST.s390x > @@ -26,3 +26,4 @@ user_ringbuf # failed to find kernel BTF type ID of > verif_stats # trace_vprintk__open_and_load unexpected error: -9 (?) > xdp_bonding # failed to auto-attach program 'trace_on_entry': -524 (trampoline) > xdp_metadata # JIT does not support calling kernel function (kfunc) > +test_task_under_cgroup # JIT does not support calling kernel function (kfunc) > diff --git a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c > new file mode 100644 > index 000000000000..5e79dff86dec > --- /dev/null > +++ b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c > @@ -0,0 +1,55 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2023 Bytedance */ > + > +#include <sys/syscall.h> > +#include <test_progs.h> > +#include <cgroup_helpers.h> > +#include "test_task_under_cgroup.skel.h" > + > +#define FOO "/foo" > + > +void test_task_under_cgroup(void) > +{ > + struct test_task_under_cgroup *skel; > + int ret, foo = -1; > + pid_t pid; > + > + foo = test__join_cgroup(FOO); > + if (!ASSERT_OK(foo < 0, "cgroup_join_foo")) > + return; > + > + skel = test_task_under_cgroup__open(); > + if (!ASSERT_OK_PTR(skel, "test_task_under_cgroup__open")) > + goto cleanup; > + > + skel->rodata->local_pid = getpid(); > + skel->bss->remote_pid = getpid(); > + skel->rodata->cgid = get_cgroup_id(FOO); > + > + ret = test_task_under_cgroup__load(skel); > + if (!ASSERT_OK(ret, "test_task_under_cgroup__load")) > + goto cleanup; > + > + ret = test_task_under_cgroup__attach(skel); > + if (!ASSERT_OK(ret, "test_task_under_cgroup__attach")) > + goto cleanup; > + > + pid = fork(); > + if (pid == 0) > + exit(0); > + else if (pid == -1) > + printf("Couldn't fork process!\n"); ASSERT_* is preferred compared to 'printf'. Maybe ASSERT_TRUE(0, "Couldn't fork process")? > + > + wait(NULL); > + > + test_task_under_cgroup__detach(skel); > + > + ASSERT_NEQ(skel->bss->remote_pid, skel->rodata->local_pid, > + "test task_under_cgroup"); > + > +cleanup: > + if (foo >= 0) "if (foo >= 0)" is not needed. 'foo' is guaranteed ">= 0" as this point. > + close(foo); > + > + test_task_under_cgroup__destroy(skel); > +} > diff --git a/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c > new file mode 100644 > index 000000000000..5bcb726d6d0a > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c > @@ -0,0 +1,51 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2023 Bytedance */ > + > +#include <vmlinux.h> > +#include <bpf/bpf_tracing.h> > +#include <bpf/bpf_helpers.h> > + > +#include "bpf_misc.h" > + > +struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym; > +long bpf_task_under_cgroup(struct task_struct *task, struct cgroup *ancestor) __ksym; > +void bpf_cgroup_release(struct cgroup *p) __ksym; > +struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym; > +void bpf_task_release(struct task_struct *p) __ksym; > + > +const volatile int local_pid; > +const volatile long cgid; cgid cannot be a negative number. So let us do const volatile __u64 cgid; > +int remote_pid; > + > +SEC("tp_btf/task_newtask") > +int BPF_PROG(handle__task_newtask, struct task_struct *task, u64 clone_flags) > +{ > + struct cgroup *cgrp = NULL; > + struct task_struct *acquired = NULL; "acquired = NULL" is not needed. Just do "struct task_struct *acquired;". > + > + if (local_pid != (bpf_get_current_pid_tgid() >> 32)) > + return 0; > + > + acquired = bpf_task_acquire(task); > + if (!acquired) > + return 0; > + > + if (local_pid == acquired->tgid) > + goto out; > + > + cgrp = bpf_cgroup_from_id(cgid); > + if (!cgrp) > + goto out; > + > + if (bpf_task_under_cgroup(acquired, cgrp)) > + remote_pid = acquired->tgid; > + > +out: > + if (acquired) > + bpf_task_release(acquired); > + if (cgrp) > + bpf_cgroup_release(cgrp); > + return 0; > +} > + > +char _license[] SEC("license") = "GPL";
在 2023/4/29 00:32, Yonghong Song 写道: > > > On 4/28/23 12:17 AM, Feng zhou wrote: >> From: Feng Zhou <zhoufeng.zf@bytedance.com> >> >> test_progs: >> Tests new kfunc bpf_task_under_cgroup(). >> >> The bpf program saves the new task's pid within a given cgroup to >> the remote_pid, which is convenient for the user-mode program to >> verify the test correctness. >> >> The user-mode program creates its own mount namespace, and mounts the >> cgroupsv2 hierarchy in there, call the fork syscall, then check if >> remote_pid and local_pid are unequal. >> >> Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com> > > Ack with a few nits below. > > Acked-by: Yonghong Song <yhs@fb.com> > >> --- >> tools/testing/selftests/bpf/DENYLIST.s390x | 1 + >> .../bpf/prog_tests/task_under_cgroup.c | 55 +++++++++++++++++++ >> .../bpf/progs/test_task_under_cgroup.c | 51 +++++++++++++++++ >> 3 files changed, 107 insertions(+) >> create mode 100644 >> tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> create mode 100644 >> tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> >> diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x >> b/tools/testing/selftests/bpf/DENYLIST.s390x >> index c7463f3ec3c0..5061d9e24c16 100644 >> --- a/tools/testing/selftests/bpf/DENYLIST.s390x >> +++ b/tools/testing/selftests/bpf/DENYLIST.s390x >> @@ -26,3 +26,4 @@ user_ringbuf # failed to >> find kernel BTF type ID of >> verif_stats # >> trace_vprintk__open_and_load unexpected error: >> -9 (?) >> xdp_bonding # failed to auto-attach >> program 'trace_on_entry': -524 (trampoline) >> xdp_metadata # JIT does not support >> calling kernel function (kfunc) >> +test_task_under_cgroup # JIT does not support >> calling kernel function (kfunc) >> diff --git >> a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> new file mode 100644 >> index 000000000000..5e79dff86dec >> --- /dev/null >> +++ b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> @@ -0,0 +1,55 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* Copyright (c) 2023 Bytedance */ >> + >> +#include <sys/syscall.h> >> +#include <test_progs.h> >> +#include <cgroup_helpers.h> >> +#include "test_task_under_cgroup.skel.h" >> + >> +#define FOO "/foo" >> + >> +void test_task_under_cgroup(void) >> +{ >> + struct test_task_under_cgroup *skel; >> + int ret, foo = -1; >> + pid_t pid; >> + >> + foo = test__join_cgroup(FOO); >> + if (!ASSERT_OK(foo < 0, "cgroup_join_foo")) >> + return; >> + >> + skel = test_task_under_cgroup__open(); >> + if (!ASSERT_OK_PTR(skel, "test_task_under_cgroup__open")) >> + goto cleanup; >> + >> + skel->rodata->local_pid = getpid(); >> + skel->bss->remote_pid = getpid(); >> + skel->rodata->cgid = get_cgroup_id(FOO); >> + >> + ret = test_task_under_cgroup__load(skel); >> + if (!ASSERT_OK(ret, "test_task_under_cgroup__load")) >> + goto cleanup; >> + >> + ret = test_task_under_cgroup__attach(skel); >> + if (!ASSERT_OK(ret, "test_task_under_cgroup__attach")) >> + goto cleanup; >> + >> + pid = fork(); >> + if (pid == 0) >> + exit(0); >> + else if (pid == -1) >> + printf("Couldn't fork process!\n"); > > ASSERT_* is preferred compared to 'printf'. Maybe ASSERT_TRUE(0, > "Couldn't fork process")? > Will do. >> + >> + wait(NULL); >> + >> + test_task_under_cgroup__detach(skel); >> + >> + ASSERT_NEQ(skel->bss->remote_pid, skel->rodata->local_pid, >> + "test task_under_cgroup"); >> + >> +cleanup: >> + if (foo >= 0) > > "if (foo >= 0)" is not needed. 'foo' is guaranteed ">= 0" as this point. > Yes >> + close(foo); >> + >> + test_task_under_cgroup__destroy(skel); >> +} >> diff --git >> a/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> new file mode 100644 >> index 000000000000..5bcb726d6d0a >> --- /dev/null >> +++ b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> @@ -0,0 +1,51 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* Copyright (c) 2023 Bytedance */ >> + >> +#include <vmlinux.h> >> +#include <bpf/bpf_tracing.h> >> +#include <bpf/bpf_helpers.h> >> + >> +#include "bpf_misc.h" >> + >> +struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym; >> +long bpf_task_under_cgroup(struct task_struct *task, struct cgroup >> *ancestor) __ksym; >> +void bpf_cgroup_release(struct cgroup *p) __ksym; >> +struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym; >> +void bpf_task_release(struct task_struct *p) __ksym; >> + >> +const volatile int local_pid; >> +const volatile long cgid; > > cgid cannot be a negative number. So let us do > const volatile __u64 cgid; > Ok >> +int remote_pid; >> + >> +SEC("tp_btf/task_newtask") >> +int BPF_PROG(handle__task_newtask, struct task_struct *task, u64 >> clone_flags) >> +{ >> + struct cgroup *cgrp = NULL; >> + struct task_struct *acquired = NULL; > > "acquired = NULL" is not needed. Just do "struct task_struct *acquired;". > Ok >> + >> + if (local_pid != (bpf_get_current_pid_tgid() >> 32)) >> + return 0; >> + >> + acquired = bpf_task_acquire(task); >> + if (!acquired) >> + return 0; >> + >> + if (local_pid == acquired->tgid) >> + goto out; >> + >> + cgrp = bpf_cgroup_from_id(cgid); >> + if (!cgrp) >> + goto out; >> + >> + if (bpf_task_under_cgroup(acquired, cgrp)) >> + remote_pid = acquired->tgid; >> + >> +out: >> + if (acquired) >> + bpf_task_release(acquired); >> + if (cgrp) >> + bpf_cgroup_release(cgrp); >> + return 0; >> +} >> + >> +char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x b/tools/testing/selftests/bpf/DENYLIST.s390x index c7463f3ec3c0..5061d9e24c16 100644 --- a/tools/testing/selftests/bpf/DENYLIST.s390x +++ b/tools/testing/selftests/bpf/DENYLIST.s390x @@ -26,3 +26,4 @@ user_ringbuf # failed to find kernel BTF type ID of verif_stats # trace_vprintk__open_and_load unexpected error: -9 (?) xdp_bonding # failed to auto-attach program 'trace_on_entry': -524 (trampoline) xdp_metadata # JIT does not support calling kernel function (kfunc) +test_task_under_cgroup # JIT does not support calling kernel function (kfunc) diff --git a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c new file mode 100644 index 000000000000..5e79dff86dec --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Bytedance */ + +#include <sys/syscall.h> +#include <test_progs.h> +#include <cgroup_helpers.h> +#include "test_task_under_cgroup.skel.h" + +#define FOO "/foo" + +void test_task_under_cgroup(void) +{ + struct test_task_under_cgroup *skel; + int ret, foo = -1; + pid_t pid; + + foo = test__join_cgroup(FOO); + if (!ASSERT_OK(foo < 0, "cgroup_join_foo")) + return; + + skel = test_task_under_cgroup__open(); + if (!ASSERT_OK_PTR(skel, "test_task_under_cgroup__open")) + goto cleanup; + + skel->rodata->local_pid = getpid(); + skel->bss->remote_pid = getpid(); + skel->rodata->cgid = get_cgroup_id(FOO); + + ret = test_task_under_cgroup__load(skel); + if (!ASSERT_OK(ret, "test_task_under_cgroup__load")) + goto cleanup; + + ret = test_task_under_cgroup__attach(skel); + if (!ASSERT_OK(ret, "test_task_under_cgroup__attach")) + goto cleanup; + + pid = fork(); + if (pid == 0) + exit(0); + else if (pid == -1) + printf("Couldn't fork process!\n"); + + wait(NULL); + + test_task_under_cgroup__detach(skel); + + ASSERT_NEQ(skel->bss->remote_pid, skel->rodata->local_pid, + "test task_under_cgroup"); + +cleanup: + if (foo >= 0) + close(foo); + + test_task_under_cgroup__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c new file mode 100644 index 000000000000..5bcb726d6d0a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Bytedance */ + +#include <vmlinux.h> +#include <bpf/bpf_tracing.h> +#include <bpf/bpf_helpers.h> + +#include "bpf_misc.h" + +struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym; +long bpf_task_under_cgroup(struct task_struct *task, struct cgroup *ancestor) __ksym; +void bpf_cgroup_release(struct cgroup *p) __ksym; +struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym; +void bpf_task_release(struct task_struct *p) __ksym; + +const volatile int local_pid; +const volatile long cgid; +int remote_pid; + +SEC("tp_btf/task_newtask") +int BPF_PROG(handle__task_newtask, struct task_struct *task, u64 clone_flags) +{ + struct cgroup *cgrp = NULL; + struct task_struct *acquired = NULL; + + if (local_pid != (bpf_get_current_pid_tgid() >> 32)) + return 0; + + acquired = bpf_task_acquire(task); + if (!acquired) + return 0; + + if (local_pid == acquired->tgid) + goto out; + + cgrp = bpf_cgroup_from_id(cgid); + if (!cgrp) + goto out; + + if (bpf_task_under_cgroup(acquired, cgrp)) + remote_pid = acquired->tgid; + +out: + if (acquired) + bpf_task_release(acquired); + if (cgrp) + bpf_cgroup_release(cgrp); + return 0; +} + +char _license[] SEC("license") = "GPL";