There is a static checker warning that the %d in format string is
mismatched with the corresponding argument type, which could result in
incorrect printed data. This patch fixes it.
Signed-off-by: Luo Yifan <luoyifan@cmss.chinamobile.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241111021004.272293-1-luoyifan@cmss.chinamobile.com
Logic to prevent callbacks from acquiring new references for the program
(i.e. leaving acquired references), and releasing caller references
(i.e. those acquired in parent frames) was introduced in commit
9d9d00ac29 ("bpf: Fix reference state management for synchronous callbacks").
This was necessary because back then, the verifier simulated each
callback once (that could potentially be executed N times, where N can
be zero). This meant that callbacks that left lingering resources or
cleared caller resources could do it more than once, operating on
undefined state or leaking memory.
With the fixes to callback verification in commit
ab5cfac139 ("bpf: verify callbacks as if they are called unknown number of times"),
all of this extra logic is no longer necessary. Hence, drop it as part
of this commit.
Cc: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241109231430.2475236-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
The timer_lockup test needs 2 CPUs to work, on single-CPU nodes it fails
to set thread affinity to CPU 1 since it doesn't exist:
# ./test_progs -t timer_lockup
test_timer_lockup:PASS:timer_lockup__open_and_load 0 nsec
test_timer_lockup:PASS:pthread_create thread1 0 nsec
test_timer_lockup:PASS:pthread_create thread2 0 nsec
timer_lockup_thread:PASS:cpu affinity 0 nsec
timer_lockup_thread:FAIL:cpu affinity unexpected error: 22 (errno 0)
test_timer_lockup:PASS: 0 nsec
#406 timer_lockup:FAIL
Skip the test if only 1 CPU is available.
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Fixes: 50bd5a0c65 ("selftests/bpf: Add timer lockup selftest")
Tested-by: Philo Lu <lulie@linux.alibaba.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241107115231.75200-1-vmalik@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Add test cases to verify the following four update operations on htab of
maps don't trigger lockdep warning:
(1) add then delete
(2) add, overwrite, then delete
(3) add, then lookup_and_delete
(4) add two elements, then lookup_and_delete_batch
Test cases are added for pre-allocated and non-preallocated htab of maps
respectively.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20241106063542.357743-4-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Moving the definition of ENOTSUPP into bpf_util.h to remove the
duplicated definitions in multiple files.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20241106063542.357743-3-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
With recent uprobe fix [1] the sync time after unregistering uprobe is
much longer and prolongs the consumer test which creates and destroys
hundreds of uprobes.
This change adds 16 threads (which fits the test logic) and speeds up
the test.
Before the change:
# perf stat --null ./test_progs -t uprobe_multi_test/consumers
#421/9 uprobe_multi_test/consumers:OK
#421 uprobe_multi_test:OK
Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED
Performance counter stats for './test_progs -t uprobe_multi_test/consumers':
28.818778973 seconds time elapsed
0.745518000 seconds user
0.919186000 seconds sys
After the change:
# perf stat --null ./test_progs -t uprobe_multi_test/consumers 2>&1
#421/9 uprobe_multi_test/consumers:OK
#421 uprobe_multi_test:OK
Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED
Performance counter stats for './test_progs -t uprobe_multi_test/consumers':
3.504790814 seconds time elapsed
0.012141000 seconds user
0.751760000 seconds sys
[1] commit 87195a1ee3 ("uprobes: switch to RCU Tasks Trace flavor for better performance")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-14-jolsa@kernel.org
Adding uprobe session consumers to the consumer test,
so we get the session into the test mix.
In addition scaling down the test to have just 1 uprobe
and 1 uretprobe, otherwise the test time grows and is
unsuitable for CI even with threads.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-13-jolsa@kernel.org
Testing that the session ret_handler bypass works on single
uprobe with multiple consumers, each with different session
ignore return value.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-12-jolsa@kernel.org
Making sure kprobe.session program can return only [0,1] values.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-11-jolsa@kernel.org
Making sure uprobe.session program can return only [0,1] values.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-10-jolsa@kernel.org
Adding uprobe session test that verifies the cookie value is stored
properly when single uprobe-ed function is executed recursively.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-9-jolsa@kernel.org
Adding uprobe session test that verifies the cookie value
get properly propagated from entry to return program.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-8-jolsa@kernel.org
Adding uprobe session test and testing that the entry program
return value controls execution of the return probe program.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-7-jolsa@kernel.org
Adding support to attach program in uprobe session mode
with bpf_program__attach_uprobe_multi function.
Adding session bool to bpf_uprobe_multi_opts struct that allows
to load and attach the bpf program via uprobe session.
the attachment to create uprobe multi session.
Also adding new program loader section that allows:
SEC("uprobe.session/bpf_fentry_test*")
and loads/attaches uprobe program as uprobe session.
Adding sleepable hook (uprobe.session.s) as well.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-6-jolsa@kernel.org
Adding support to attach BPF program for entry and return probe
of the same function. This is common use case which at the moment
requires to create two uprobe multi links.
Adding new BPF_TRACE_UPROBE_SESSION attach type that instructs
kernel to attach single link program to both entry and exit probe.
It's possible to control execution of the BPF program on return
probe simply by returning zero or non zero from the entry BPF
program execution to execute or not the BPF program on return
probe respectively.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241108134544.480660-4-jolsa@kernel.org
The new uprobe changes bring some new behaviour that we need to reflect
in the consumer test. Now pending uprobe instance in the kernel can
survive longer and thus might call uretprobe consumer callbacks in
some situations in which, previously, such callback would be omitted.
We now need to take that into account in uprobe-multi consumer tests.
The idea being that uretprobe under test either stayed from before to
after (uret_stays + test_bit) or uretprobe instance survived and we
have uretprobe active in after (uret_survives + test_bit).
uret_survives just states that uretprobe survives if there are *any*
uretprobes both before and after (overlapping or not, doesn't matter)
and uprobe was attached before.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241107094337.3848210-1-jolsa@kernel.org
In order to specify extra compilation or linking flags to BPF selftests,
it is possible to set EXTRA_CFLAGS and EXTRA_LDFLAGS from the command
line. The problem is that they are not propagated to sub-make calls
(runqslower, bpftool, libbpf) and in the better case are not applied, in
the worse case cause the entire build fail.
Propagate EXTRA_CFLAGS and EXTRA_LDFLAGS to the sub-makes.
This, for instance, allows to build selftests as PIE with
$ make EXTRA_CFLAGS='-fPIE' EXTRA_LDFLAGS='-pie'
Without this change, the command would fail because libbpf.a would not
be built with -fPIE and other PIE binaries would not link against it.
The only problem is that we have to explicitly provide empty
EXTRA_CFLAGS='' and EXTRA_LDFLAGS='' to the builds of kernel modules as
we don't want to build modules with flags used for userspace (the above
example would fail as kernel doesn't support PIE).
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Ensure that trusted PTR_TO_BTF_ID accesses perform PROBE_MEM handling in
raw_tp program. Without the previous fix, this selftest crashes the
kernel due to a NULL-pointer dereference. Also ensure that dead code
elimination does not kick in for checks on the pointer.
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241104171959.2938862-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Availability of the gettid definition across glibc versions supported by
BPF selftests is not certain. Currently, all users in the tree open-code
syscall to gettid. Convert them to a common macro definition.
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241104171959.2938862-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Arguments to a raw tracepoint are tagged as trusted, which carries the
semantics that the pointer will be non-NULL. However, in certain cases,
a raw tracepoint argument may end up being NULL. More context about this
issue is available in [0].
Thus, there is a discrepancy between the reality, that raw_tp arguments
can actually be NULL, and the verifier's knowledge, that they are never
NULL, causing explicit NULL checks to be deleted, and accesses to such
pointers potentially crashing the kernel.
To fix this, mark raw_tp arguments as PTR_MAYBE_NULL, and then special
case the dereference and pointer arithmetic to permit it, and allow
passing them into helpers/kfuncs; these exceptions are made for raw_tp
programs only. Ensure that we don't do this when ref_obj_id > 0, as in
that case this is an acquired object and doesn't need such adjustment.
The reason we do mask_raw_tp_trusted_reg logic is because other will
recheck in places whether the register is a trusted_reg, and then
consider our register as untrusted when detecting the presence of the
PTR_MAYBE_NULL flag.
To allow safe dereference, we enable PROBE_MEM marking when we see loads
into trusted pointers with PTR_MAYBE_NULL.
While trusted raw_tp arguments can also be passed into helpers or kfuncs
where such broken assumption may cause issues, a future patch set will
tackle their case separately, as PTR_TO_BTF_ID (without PTR_TRUSTED) can
already be passed into helpers and causes similar problems. Thus, they
are left alone for now.
It is possible that these checks also permit passing non-raw_tp args
that are trusted PTR_TO_BTF_ID with null marking. In such a case,
allowing dereference when pointer is NULL expands allowed behavior, so
won't regress existing programs, and the case of passing these into
helpers is the same as above and will be dealt with later.
Also update the failure case in tp_btf_nullable selftest to capture the
new behavior, as the verifier will no longer cause an error when
directly dereference a raw tracepoint argument marked as __nullable.
[0]: https://lore.kernel.org/bpf/ZrCZS6nisraEqehw@jlelli-thinkpadt14gen4.remote.csb
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Reported-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Fixes: 3f00c52393 ("bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241104171959.2938862-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There are similar checks for covering locks, references, RCU read
sections and preempt_disable sections in 3 places in the verifer, i.e.
for tail calls, bpf_ld_[abs, ind], and exit path (for BPF_EXIT and
bpf_throw). Unify all of these into a common check_resource_leak
function to avoid code duplication.
Also update the error strings in selftests to the new ones in the same
change to ensure clean bisection.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241103225940.1408302-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There exist compiler flags supported by GCC but not supported by Clang
(e.g. -specs=...). Currently, these cannot be passed to BPF selftests
builds, even when building with GCC, as some binaries (urandom_read and
liburandom_read.so) are always built with Clang and the unsupported
flags make the compilation fail (as -Werror is turned on).
Add -Wno-unused-command-line-argument to these rules to suppress such
errors.
This allows to do things like:
$ CFLAGS="-specs=/usr/lib/rpm/redhat/redhat-hardened-cc1" \
make -C tools/testing/selftests/bpf
Without this patch, the compilation would fail with:
[...]
clang: error: argument unused during compilation: '-specs=/usr/lib/rpm/redhat/redhat-hardened-cc1' [-Werror,-Wunused-command-line-argument]
make: *** [Makefile:273: /bpf-next/tools/testing/selftests/bpf/liburandom_read.so] Error 1
[...]
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/2d349e9d5eb0a79dd9ff94b496769d64e6ff7654.1730449390.git.vmalik@redhat.com
When building selftests with CFLAGS set via env variable, the value of
CFLAGS is propagated into bpftool Makefile (called from selftests
Makefile). This makes the compilation fail as _GNU_SOURCE is defined two
times - once from selftests Makefile (by including lib.mk) and once from
bpftool Makefile (by calling `llvm-config --cflags`):
$ CFLAGS="" make -C tools/testing/selftests/bpf
[...]
CC /bpf-next/tools/testing/selftests/bpf/tools/build/bpftool/btf.o
<command-line>: error: "_GNU_SOURCE" redefined [-Werror]
<command-line>: note: this is the location of the previous definition
cc1: all warnings being treated as errors
[...]
Filter out -D_GNU_SOURCE from the result of `llvm-config --cflags` in
bpftool Makefile to prevent this error.
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/acec3108b62d4df1436cda777e58e93e033ac7a7.1730449390.git.vmalik@redhat.com
This patch addresses the bpftool issue "Wrong callq address displayed"[0].
The issue stemmed from an incorrect program counter (PC) value used during
disassembly with LLVM or libbfd.
For LLVM: The PC argument must represent the actual address in the kernel
to compute the correct relative address.
For libbfd: The relative address can be adjusted by adding func_ksym within
the custom info->print_address_func to yield the correct address.
Links:
[0] https://github.com/libbpf/bpftool/issues/109
Changes:
v2 -> v3:
* Address comment from Quentin:
* Remove the typedef.
v1 -> v2:
* Fix the broken libbfd disassembler.
Fixes: e1947c750f ("bpftool: Refactor disassembler for JIT-ed programs")
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Quentin Monnet <qmo@kernel.org>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20241031152844.68817-1-leon.hwang@linux.dev
The new subtest runs with bpf_prog_test_run_opts() as a syscall prog.
It iterates the kmem_cache using bpf_for_each loop and count the number
of entries. Finally it checks it with the number of entries from the
regular iterator.
$ ./vmtest.sh -- ./test_progs -t kmem_cache_iter
...
#130/1 kmem_cache_iter/check_task_struct:OK
#130/2 kmem_cache_iter/check_slabinfo:OK
#130/3 kmem_cache_iter/open_coded_iter:OK
#130 kmem_cache_iter:OK
Summary: 1/3 PASSED, 0 SKIPPED, 0 FAILED
Also simplify the code by using attach routine of the skeleton.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241030222819.1800667-2-namhyung@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Drop bpf_iter.h header which uses vmlinux.h but re-defines a bunch of
iterator structures and some of BPF constants for use in BPF iterator
selftests.
None of that is necessary when fresh vmlinux.h header is generated for
vmlinux image that matches latest selftests. So drop ugly hacks and have
a nice plain vmlinux.h usage everywhere.
We could do the same with all the kfunc __ksym redefinitions, but that
has dependency on very fresh pahole, so I'm not addressing that here.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241029203919.1948941-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
As we can see from the title, when I compiled the selftests/bpf, I
saw the error:
implicit declaration of function ‘gettid’ ; did you mean ‘getgid’? [-Werror=implicit-function-declaration]
skel->bss->tid = gettid();
^~~~~~
getgid
Directly call the syscall solves this issue.
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/r/20241029074627.80289-1-kerneljasonxing@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
- Fix an out-of-bounds read in bpf_link_show_fdinfo for BPF
sockmap link file descriptors (Hou Tao)
- Fix BPF arm64 JIT's address emission with tag-based KASAN
enabled reserving not enough size (Peter Collingbourne)
- Fix BPF verifier do_misc_fixups patching for inlining of the
bpf_get_branch_snapshot BPF helper (Andrii Nakryiko)
- Fix a BPF verifier bug and reject BPF program write attempts
into read-only marked BPF maps (Daniel Borkmann)
- Fix perf_event_detach_bpf_prog error handling by removing an
invalid check which would skip BPF program release (Jiri Olsa)
- Fix memory leak when parsing mount options for the BPF
filesystem (Hou Tao)
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:
- Fix an out-of-bounds read in bpf_link_show_fdinfo for BPF sockmap
link file descriptors (Hou Tao)
- Fix BPF arm64 JIT's address emission with tag-based KASAN enabled
reserving not enough size (Peter Collingbourne)
- Fix BPF verifier do_misc_fixups patching for inlining of the
bpf_get_branch_snapshot BPF helper (Andrii Nakryiko)
- Fix a BPF verifier bug and reject BPF program write attempts into
read-only marked BPF maps (Daniel Borkmann)
- Fix perf_event_detach_bpf_prog error handling by removing an invalid
check which would skip BPF program release (Jiri Olsa)
- Fix memory leak when parsing mount options for the BPF filesystem
(Hou Tao)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Check validity of link->type in bpf_link_show_fdinfo()
bpf: Add the missing BPF_LINK_TYPE invocation for sockmap
bpf: fix do_misc_fixups() for bpf_get_branch_snapshot()
bpf,perf: Fix perf_event_detach_bpf_prog error handling
selftests/bpf: Add test for passing in uninit mtu_len
selftests/bpf: Add test for writes to .rodata
bpf: Remove MEM_UNINIT from skb/xdp MTU helpers
bpf: Fix overloading of MEM_UNINIT's meaning
bpf: Add MEM_WRITE attribute
bpf: Preserve param->string when parsing mount options
bpf, arm64: Fix address emission with tag-based KASAN enabled
This patch tests the map creation failure when the map_value
has unsupported uptr. The three cases are the struct is larger
than one page, the struct is empty, and the struct is a kernel struct.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20241023234759.860539-13-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch test the following failures in syscall update_elem
1. The first update_elem(BPF_F_LOCK) should be EOPNOTSUPP. syscall.c takes
care of unpinning the uptr.
2. The second update_elem(BPF_EXIST) fails. syscall.c takes care of
unpinning the uptr.
3. The forth update_elem(BPF_NOEXIST) fails. bpf_local_storage_update
takes care of unpinning the uptr.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20241023234759.860539-11-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch tests the case when uptr has a struct spanning across two
pages. It is not supported now and EOPNOTSUPP is expected from the
syscall update_elem.
It also tests the whole uptr struct located exactly at the
end of a page and ensures that this case is accepted by update_elem.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20241023234759.860539-10-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make sure the memory of uptrs have been mapped to the kernel properly.
Also ensure the values of uptrs in the kernel haven't been copied
to userspace.
It also has the syscall update_elem/delete_elem test to test the
pin/unpin code paths.
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20241023234759.860539-9-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make __uptr available to BPF programs to enable them to define uptrs.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20241023234759.860539-8-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There is an out-of-bounds read in bpf_link_show_fdinfo() for the sockmap
link fd. Fix it by adding the missing BPF_LINK_TYPE invocation for
sockmap link
Also add comments for bpf_link_type to prevent missing updates in the
future.
Fixes: 699c23f02c ("bpf: Add bpf_link support for sk_msg and sk_skb progs")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241024013558.1135167-2-houtao@huaweicloud.com
Add a new subtest validating that bpf_object loaded and initialized
through generic APIs is still interoperable with BPF subskeleton,
including initialization and reading of global variables.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241023043908.3834423-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since BPF skeleton inception libbpf has been doing mmap()'ing of global
data ARRAY maps in bpf_object__load_skeleton() API, which is used by
code generated .skel.h files (i.e., by BPF skeletons only).
This is wrong because if BPF object is loaded through generic
bpf_object__load() API, global data maps won't be re-mmap()'ed after
load step, and memory pointers returned from bpf_map__initial_value()
would be wrong and won't reflect the actual memory shared between BPF
program and user space.
bpf_map__initial_value() return result is rarely used after load, so
this went unnoticed for a really long time, until bpftrace project
attempted to load BPF object through generic bpf_object__load() API and
then used BPF subskeleton instantiated from such bpf_object. It turned
out that .data/.rodata/.bss data updates through such subskeleton was
"blackholed", all because libbpf wouldn't re-mmap() those maps during
bpf_object__load() phase.
Long story short, this step should be done by libbpf regardless of BPF
skeleton usage, right after BPF map is created in the kernel. This patch
moves this functionality into bpf_object__populate_internal_map() to
achieve this. And bpf_object__load_skeleton() is now simple and almost
trivial, only propagating these mmap()'ed pointers into user-supplied
skeleton structs.
We also do trivial adjustments to error reporting inside
bpf_object__populate_internal_map() for consistency with the rest of
libbpf's map-handling code.
Reported-by: Alastair Robertson <ajor@meta.com>
Reported-by: Jonathan Wiepert <jwiepert@meta.com>
Fixes: d66562fba1 ("libbpf: Add BPF object skeleton support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241023043908.3834423-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Global variables of special types (like `struct bpf_spin_lock`) make
underlying ARRAY maps non-mmapable. To make this work with libbpf's
mmaping logic, application is expected to declare such special variables
as static, so libbpf doesn't even attempt to mmap() such ARRAYs.
test_spin_lock_fail.c didn't follow this rule, but given it relied on
this test to trigger failures, this went unnoticed, as we never got to
the step of mmap()'ing these ARRAY maps.
It is fragile and relies on specific sequence of libbpf steps, which are
an internal implementation details.
Fix the test by marking lockA and lockB as static.
Fixes: c48748aea4 ("selftests/bpf: Add failure test cases for spin lock pairing")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241023043908.3834423-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Initialize the pointer 'o' in options__order to NULL to prevent a
compiler warning/error which is observed when compiling with the '-Og'
option, but is not emitted by the compiler with the current default
compilation options.
For example, when compiling libsubcmd with
$ make "EXTRA_CFLAGS=-Og" -C tools/lib/subcmd/ clean all
Clang version 17.0.6 and GCC 13.3.1 fail to compile parse-options.c due
to following error:
parse-options.c: In function ‘options__order’:
parse-options.c:832:9: error: ‘o’ may be used uninitialized [-Werror=maybe-uninitialized]
832 | memcpy(&ordered[nr_opts], o, sizeof(*o));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
parse-options.c:810:30: note: ‘o’ was declared here
810 | const struct option *o, *p = opts;
| ^
cc1: all warnings being treated as errors
Signed-off-by: Eder Zulian <ezulian@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20241022172329.3871958-4-ezulian@redhat.com
Initialize 'new_off' and 'pad_bits' to 0 and 'pad_type' to NULL in
btf_dump_emit_bit_padding to prevent compiler warnings/errors which are
observed when compiling with 'EXTRA_CFLAGS=-g -Og' options, but do not
happen when compiling with current default options.
For example, when compiling libbpf with
$ make "EXTRA_CFLAGS=-g -Og" -C tools/lib/bpf/ clean all
Clang version 17.0.6 and GCC 13.3.1 fail to compile btf_dump.c due to
following errors:
btf_dump.c: In function ‘btf_dump_emit_bit_padding’:
btf_dump.c:903:42: error: ‘new_off’ may be used uninitialized [-Werror=maybe-uninitialized]
903 | if (new_off > cur_off && new_off <= next_off) {
| ~~~~~~~~^~~~~~~~~~~
btf_dump.c:870:13: note: ‘new_off’ was declared here
870 | int new_off, pad_bits, bits, i;
| ^~~~~~~
btf_dump.c:917:25: error: ‘pad_type’ may be used uninitialized [-Werror=maybe-uninitialized]
917 | btf_dump_printf(d, "\n%s%s: %d;", pfx(lvl), pad_type,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
918 | in_bitfield ? new_off - cur_off : 0);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
btf_dump.c:871:21: note: ‘pad_type’ was declared here
871 | const char *pad_type;
| ^~~~~~~~
btf_dump.c:930:20: error: ‘pad_bits’ may be used uninitialized [-Werror=maybe-uninitialized]
930 | if (bits == pad_bits) {
| ^
btf_dump.c:870:22: note: ‘pad_bits’ was declared here
870 | int new_off, pad_bits, bits, i;
| ^~~~~~~~
cc1: all warnings being treated as errors
Signed-off-by: Eder Zulian <ezulian@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20241022172329.3871958-3-ezulian@redhat.com
Initialize 'set' and 'set8' pointers to NULL in sets_patch to prevent
possible compiler warnings which are issued for various optimization
levels, but do not happen when compiling with current default
compilation options.
For example, when compiling resolve_btfids with
$ make "HOSTCFLAGS=-O2 -Wall" -C tools/bpf/resolve_btfids/ clean all
Clang version 17.0.6 and GCC 13.3.1 issue following
-Wmaybe-uninitialized warnings for variables 'set8' and 'set':
In function ‘sets_patch’,
inlined from ‘symbols_patch’ at main.c:748:6,
inlined from ‘main’ at main.c:823:6:
main.c:163:9: warning: ‘set8’ may be used uninitialized [-Wmaybe-uninitialized]
163 | eprintf(1, verbose, pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
main.c:729:17: note: in expansion of macro ‘pr_debug’
729 | pr_debug("sorting addr %5lu: cnt %6d [%s]\n",
| ^~~~~~~~
main.c: In function ‘main’:
main.c:682:37: note: ‘set8’ was declared here
682 | struct btf_id_set8 *set8;
| ^~~~
In function ‘sets_patch’,
inlined from ‘symbols_patch’ at main.c:748:6,
inlined from ‘main’ at main.c:823:6:
main.c:163:9: warning: ‘set’ may be used uninitialized [-Wmaybe-uninitialized]
163 | eprintf(1, verbose, pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
main.c:729:17: note: in expansion of macro ‘pr_debug’
729 | pr_debug("sorting addr %5lu: cnt %6d [%s]\n",
| ^~~~~~~~
main.c: In function ‘main’:
main.c:683:36: note: ‘set’ was declared here
683 | struct btf_id_set *set;
| ^~~
Signed-off-by: Eder Zulian <ezulian@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20241022172329.3871958-2-ezulian@redhat.com
Adding data pointer to both entry and exit consumer handlers and all
its users. The functionality itself is coming in following change.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241018202252.693462-2-jolsa@kernel.org
The current default buffer size of 16MB allocated by veristat is no
longer sufficient to hold the verifier logs of some production BPF
programs. To address this issue, we need to increase the verifier log
limit.
Commit 7a9f5c65ab ("bpf: increase verifier log limit") has already
increased the supported buffer size by the kernel, but veristat users
need to explicitly pass a log size argument to use the bigger log.
This patch adds a function to detect the maximum verifier log size
supported by the kernel and uses that by default in veristat.
This ensures that veristat can handle larger verifier logs without
requiring users to manually specify the log size.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241023155314.126255-1-mykyta.yatsenko5@gmail.com
