selftests/bpf: add bpf_for_each(), bpf_for(), and bpf_repeat() macros

Add bpf_for_each(), bpf_for(), and bpf_repeat() macros that make writing
open-coded iterator-based loops much more convenient an

selftests/bpf: add bpf_for_each(), bpf_for(), and bpf_repeat() macros

Add bpf_for_each(), bpf_for(), and bpf_repeat() macros that make writing
open-coded iterator-based loops much more convenient and natural. These
macros utilize cleanup attribute to ensure proper destruction of the
iterator and thanks to that manage to provide the ergonomics that is
very close to C language's for() construct. Typical loop would look like:

int i;
int arr[N];

bpf_for(i, 0, N) {
/* verifier will know that i >= 0 && i < N, so could be used to
* directly access array elements with no extra checks
*/
arr[i] = i;
}

bpf_repeat() is very similar, but it doesn't expose iteration number and
is meant as a simple "repeat action N times" loop:

bpf_repeat(N) { /* whatever, N times */ }

Note that `break` and `continue` statements inside the {} block work as
expected.

bpf_for_each() is a generalization over any kind of BPF open-coded
iterator allowing to use for-each-like approach instead of calling
low-level bpf_iter_<type>_{new,next,destroy}() APIs explicitly. E.g.:

struct cgroup *cg;

bpf_for_each(cgroup, cg, some, input, args) {
/* do something with each cg */
}

would call (not-yet-implemented) bpf_iter_cgroup_{new,next,destroy}()
functions to form a loop over cgroups, where `some, input, args` are
passed verbatim into constructor as

bpf_iter_cgroup_new(&it, some, input, args).

As a first demonstration, add pyperf variant based on the bpf_for() loop.

Also clean up a few tests that either included bpf_misc.h header
unnecessarily from the user-space, which is unsupported, or included it
before any common types are defined (and thus leading to unnecessary
compilation warnings, potentially).

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230308184121.1165081-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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selftests/bpf: Fix test_lsm on s390x

Use syscall macros to access the setdomainname() arguments; currently
the code uses gprs[2] instead of orig_gpr2 for the first argument.

Signed-off-by: Ilya Leo

selftests/bpf: Fix test_lsm on s390x

Use syscall macros to access the setdomainname() arguments; currently
the code uses gprs[2] instead of orig_gpr2 for the first argument.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-16-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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selftests/bpf: Fix attach point for non-x86 arches in test_progs/lsm

Use SYS_PREFIX macro from bpf_misc.h instead of hard-coded '__x64_'
prefix for sys_setdomainname attach point in lsm test.

Signe

selftests/bpf: Fix attach point for non-x86 arches in test_progs/lsm

Use SYS_PREFIX macro from bpf_misc.h instead of hard-coded '__x64_'
prefix for sys_setdomainname attach point in lsm test.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220816055231.717006-1-asavkov@redhat.com

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selftests/bpf: Add a test for map-in-map and per-cpu maps in sleepable progs

Add a basic test for map-in-map and per-cpu maps in sleepable programs.

Signed-off-by: Alexei Starovoitov <ast@kernel.or

selftests/bpf: Add a test for map-in-map and per-cpu maps in sleepable progs

Add a basic test for map-in-map and per-cpu maps in sleepable programs.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-10-alexei.starovoitov@gmail.com

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bpf: Remove bpf_lsm_file_mprotect from sleepable list.

Technically the bpf programs can sleep while attached to bpf_lsm_file_mprotect,
but such programs need to access user memory. So they're in mig

bpf: Remove bpf_lsm_file_mprotect from sleepable list.

Technically the bpf programs can sleep while attached to bpf_lsm_file_mprotect,
but such programs need to access user memory. So they're in might_fault()
category. Which means they cannot be called from file_mprotect lsm hook that
takes write lock on mm->mmap_lock.
Adjust the test accordingly.

Also add might_fault() to __bpf_prog_enter_sleepable() to catch such deadlocks early.

Fixes: 1e6c62a88215 ("bpf: Introduce sleepable BPF programs")
Fixes: e68a144547fc ("selftests/bpf: Add sleepable tests")
Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200831201651.82447-1-alexei.starovoitov@gmail.com

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selftests/bpf: Add sleepable tests

Modify few tests to sanity test sleepable bpf functionality.

Running 'bench trig-fentry-sleep' vs 'bench trig-fentry' and 'perf report':
sleepable with SRCU:
3

selftests/bpf: Add sleepable tests

Modify few tests to sanity test sleepable bpf functionality.

Running 'bench trig-fentry-sleep' vs 'bench trig-fentry' and 'perf report':
sleepable with SRCU:
3.86% bench [k] __srcu_read_unlock
3.22% bench [k] __srcu_read_lock
0.92% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep
0.50% bench [k] bpf_trampoline_10297
0.26% bench [k] __bpf_prog_exit_sleepable
0.21% bench [k] __bpf_prog_enter_sleepable

sleepable with RCU_TRACE:
0.79% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep
0.72% bench [k] bpf_trampoline_10381
0.31% bench [k] __bpf_prog_exit_sleepable
0.29% bench [k] __bpf_prog_enter_sleepable

non-sleepable with RCU:
0.88% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry
0.84% bench [k] bpf_trampoline_10297
0.13% bench [k] __bpf_prog_enter
0.12% bench [k] __bpf_prog_exit

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200827220114.69225-6-alexei.starovoitov@gmail.com

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bpf, lsm: Fix the file_mprotect LSM test.

The test was previously using an mprotect on the heap memory allocated
using malloc and was expecting the allocation to be always using
sbrk(2). This is, ho

bpf, lsm: Fix the file_mprotect LSM test.

The test was previously using an mprotect on the heap memory allocated
using malloc and was expecting the allocation to be always using
sbrk(2). This is, however, not always true and in certain conditions
malloc may end up using anonymous mmaps for heap alloctions. This means
that the following condition that is used in the "lsm/file_mprotect"
program is not sufficent to detect all mprotect calls done on heap
memory:

is_heap = (vma->vm_start >= vma->vm_mm->start_brk &&
vma->vm_end <= vma->vm_mm->brk);

The test is updated to use an mprotect on memory allocated on the stack.
While this would result in the splitting of the vma, this happens only
after the security_file_mprotect hook. So, the condition used in the BPF
program holds true.

Fixes: 03e54f100d57 ("bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200402200751.26372-1-kpsingh@chromium.org

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bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM

* Load/attach a BPF program that hooks to file_mprotect (int)
and bprm_committed_creds (void).
* Perform an action that triggers the hook.
* Verify if

bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM

* Load/attach a BPF program that hooks to file_mprotect (int)
and bprm_committed_creds (void).
* Perform an action that triggers the hook.
* Verify if the audit event was received using the shared global
variables for the process executed.
* Verify if the mprotect returns a -EPERM.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Thomas Garnier <thgarnie@google.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-8-kpsingh@chromium.org

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bpf: Remove bpf_lsm_file_mprotect from sleepable list.

Technically the bpf programs can sleep while attached to bpf_lsm_file_mprotect,
but such programs need to access user memory. So th

bpf: Remove bpf_lsm_file_mprotect from sleepable list.

Technically the bpf programs can sleep while attached to bpf_lsm_file_mprotect,
but such programs need to access user memory. So they're in might_fault()
category. Which means they cannot be called from file_mprotect lsm hook that
takes write lock on mm->mmap_lock.
Adjust the test accordingly.

Also add might_fault() to __bpf_prog_enter_sleepable() to catch such deadlocks early.

Fixes: 1e6c62a88215 ("bpf: Introduce sleepable BPF programs")
Fixes: e68a144547fc ("selftests/bpf: Add sleepable tests")
Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200831201651.82447-1-alexei.starovoitov@gmail.com

show more ...

selftests/bpf: Add sleepable tests

Modify few tests to sanity test sleepable bpf functionality.

Running 'bench trig-fentry-sleep' vs 'bench trig-fentry' and 'perf report':
sleep

selftests/bpf: Add sleepable tests

Modify few tests to sanity test sleepable bpf functionality.

Running 'bench trig-fentry-sleep' vs 'bench trig-fentry' and 'perf report':
sleepable with SRCU:
3.86% bench [k] __srcu_read_unlock
3.22% bench [k] __srcu_read_lock
0.92% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep
0.50% bench [k] bpf_trampoline_10297
0.26% bench [k] __bpf_prog_exit_sleepable
0.21% bench [k] __bpf_prog_enter_sleepable

sleepable with RCU_TRACE:
0.79% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep
0.72% bench [k] bpf_trampoline_10381
0.31% bench [k] __bpf_prog_exit_sleepable
0.29% bench [k] __bpf_prog_enter_sleepable

non-sleepable with RCU:
0.88% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry
0.84% bench [k] bpf_trampoline_10297
0.13% bench [k] __bpf_prog_enter
0.12% bench [k] __bpf_prog_exit

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200827220114.69225-6-alexei.starovoitov@gmail.com

show more ...

bpf, lsm: Fix the file_mprotect LSM test.

The test was previously using an mprotect on the heap memory allocated
using malloc and was expecting the allocation to be always using
sbrk

bpf, lsm: Fix the file_mprotect LSM test.

The test was previously using an mprotect on the heap memory allocated
using malloc and was expecting the allocation to be always using
sbrk(2). This is, however, not always true and in certain conditions
malloc may end up using anonymous mmaps for heap alloctions. This means
that the following condition that is used in the "lsm/file_mprotect"
program is not sufficent to detect all mprotect calls done on heap
memory:

is_heap = (vma->vm_start >= vma->vm_mm->start_brk &&
vma->vm_end <= vma->vm_mm->brk);

The test is updated to use an mprotect on memory allocated on the stack.
While this would result in the splitting of the vma, this happens only
after the security_file_mprotect hook. So, the condition used in the BPF
program holds true.

Fixes: 03e54f100d57 ("bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200402200751.26372-1-kpsingh@chromium.org

show more ...

bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM

* Load/attach a BPF program that hooks to file_mprotect (int)
and bprm_committed_creds (void).
* Perform an action that triggers the h

bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM

* Load/attach a BPF program that hooks to file_mprotect (int)
and bprm_committed_creds (void).
* Perform an action that triggers the hook.
* Verify if the audit event was received using the shared global
variables for the process executed.
* Verify if the mprotect returns a -EPERM.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Thomas Garnier <thgarnie@google.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-8-kpsingh@chromium.org

show more ...