Similar to what we did for bpf_prog_load() in previous patch, wire
returning of log_true_size value from kernel back to the user through
OPTS out field.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230406234205.323208-17-andrii@kernel.org
Add output-only log_true_size field to bpf_prog_load_opts to return
bpf_attr->log_true_size value back from bpf() syscall.
Note, that we have to drop const modifier from opts in bpf_prog_load().
This could potentially cause compilation error for some users. But
the usual practice is to define bpf_prog_load_ops
as a local variable next to bpf_prog_load() call and pass pointer to it,
so const vs non-const makes no difference and won't even come up in most
(if not all) cases.
There are no runtime and ABI backwards/forward compatibility issues at all.
If user provides old struct bpf_prog_load_opts, libbpf won't set new
fields. If old libbpf is provided new bpf_prog_load_opts, nothing will
happen either as old libbpf doesn't yet know about this new field.
Adding a new variant of bpf_prog_load() just for this seems like a big
and unnecessary overkill. As a corroborating evidence is the fact that
entire selftests/bpf code base required not adjustment whatsoever.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230406234205.323208-16-andrii@kernel.org
This basically prevents any forward compatibility. And we either way
just return -EINVAL, which would otherwise be returned from bpf()
syscall anyways.
Similarly, drop enforcement of non-NULL log_buf when log_level > 0. This
won't be true anymore soon.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Lorenz Bauer <lmb@isovalent.com>
Link: https://lore.kernel.org/bpf/20230406234205.323208-5-andrii@kernel.org
ELF is acronym and therefore should be spelled in all caps.
I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like
being written in the first person.
Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If user explicitly overrides programs's type with
bpf_program__set_type() API call, we need to disassociate whatever
SEC_DEF handler libbpf determined initially based on program's SEC()
definition, as it's not goind to be valid anymore and could lead to
crashes and/or confusing failures.
Also, fix up bpf_prog_test_load() helper in selftests/bpf, which is
force-setting program type (even if that's completely unnecessary; this
is quite a legacy piece of code), and thus should expect auto-attach to
not work, yet one of the tests explicitly relies on auto-attach for
testing.
Instead, force-set program type only if it differs from the desired one.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230327185202.1929145-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Double-free error in bpf_linker__free() was reported by James Hilliard.
The error is caused by miss-use of realloc() in extend_sec().
The error occurs when two files with empty sections of the same name
are linked:
- when first file is processed:
- extend_sec() calls realloc(dst->raw_data, dst_align_sz)
with dst->raw_data == NULL and dst_align_sz == 0;
- dst->raw_data is set to a special pointer to a memory block of
size zero;
- when second file is processed:
- extend_sec() calls realloc(dst->raw_data, dst_align_sz)
with dst->raw_data == <special pointer> and dst_align_sz == 0;
- realloc() "frees" dst->raw_data special pointer and returns NULL;
- extend_sec() exits with -ENOMEM, and the old dst->raw_data value
is preserved (it is now invalid);
- eventually, bpf_linker__free() attempts to free dst->raw_data again.
This patch fixes the bug by avoiding -ENOMEM exit for dst_align_sz == 0.
The fix was suggested by Andrii Nakryiko <andrii.nakryiko@gmail.com>.
Reported-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: James Hilliard <james.hilliard1@gmail.com>
Link: https://lore.kernel.org/bpf/CADvTj4o7ZWUikKwNTwFq0O_AaX+46t_+Ca9gvWMYdWdRtTGeHQ@mail.gmail.com/
Link: https://lore.kernel.org/bpf/20230328004738.381898-3-eddyz87@gmail.com
This patch prevents races on the print function pointer, allowing the
libbpf_set_print() function to become thread-safe.
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230325010845.46000-1-inwardvessel@gmail.com
Flags a struct_ops is to back a bpf_link by putting it to the
".struct_ops.link" section. Once it is flagged, the created
struct_ops can be used to create a bpf_link or update a bpf_link that
has been backed by another struct_ops.
Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230323032405.3735486-8-kuifeng@meta.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Introduce bpf_link__update_map(), which allows to atomically update
underlying struct_ops implementation for given struct_ops BPF link.
Also add old_map_fd to struct bpf_link_update_opts to handle
BPF_F_REPLACE feature.
Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Link: https://lore.kernel.org/r/20230323032405.3735486-7-kuifeng@meta.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
bpf_map__attach_struct_ops() was creating a dummy bpf_link as a
placeholder, but now it is constructing an authentic one by calling
bpf_link_create() if the map has the BPF_F_LINK flag.
You can flag a struct_ops map with BPF_F_LINK by calling
bpf_map__set_map_flags().
Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20230323032405.3735486-5-kuifeng@meta.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
RELO_EXTERN_VAR/FUNC names are not correct anymore. RELO_EXTERN_VAR represent
ksym symbol in ld_imm64 insn. It can point to kernel variable or kfunc.
Rename RELO_EXTERN_VAR->RELO_EXTERN_LD64 and RELO_EXTERN_FUNC->RELO_EXTERN_CALL
to match what they actually represent.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230321203854.3035-2-alexei.starovoitov@gmail.com
Write data to fd by calling "vdprintf", in most implementations
of the standard library, the data is finally written by the writev syscall.
But "uprobe_events/kprobe_events" does not allow segmented writes,
so switch the "append_to_file" function to explicit write() call.
Signed-off-by: Liu Pan <patteliu@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230320030720.650-1-patteliu@gmail.com
Unlike normal libbpf the light skeleton 'loader' program is doing
btf_find_by_name_kind() call at run-time to find ksym in the kernel and
populate its {btf_id, btf_obj_fd} pair in ld_imm64 insn. To avoid doing the
search multiple times for the same ksym it remembers the first patched ld_imm64
insn and copies {btf_id, btf_obj_fd} from it into subsequent ld_imm64 insn.
Fix a bug in copying logic, since it may incorrectly clear BPF_PSEUDO_BTF_ID flag.
Also replace always true if (btf_obj_fd >= 0) check with unconditional JMP_JA
to clarify the code.
Fixes: d995816b77 ("libbpf: Avoid reload of imm for weak, unresolved, repeating ksym")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230319203014.55866-1-alexei.starovoitov@gmail.com
Introduce bpf_ksym_exists() macro that can be used by BPF programs
to detect at load time whether particular ksym (either variable or kfunc)
is present in the kernel.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230317201920.62030-4-alexei.starovoitov@gmail.com
void *p = kfunc; -> generates ld_imm64 insn.
kfunc() -> generates bpf_call insn.
libbpf patches bpf_call insn correctly while only btf_id part of ld_imm64 is
set in the former case. Which means that pointers to kfuncs in modules are not
patched correctly and the verifier rejects load of such programs due to btf_id
being out of range. Fix libbpf to patch ld_imm64 for kfunc.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230317201920.62030-3-alexei.starovoitov@gmail.com
Some consumers of libbpf compile the code base with different warnings
enabled. In a report for perf, for example, -Wpacked was set which
caused warnings about "inefficient alignment" to be emitted on a subset
of supported architectures.
With this change we silence specifically those warnings, as we intentionally
worked with packed structs.
This is a similar resolution as in b2f10cd4e8 ("perf cpumap: Fix alignment
for masks in event encoding").
Fixes: 1eebcb6063 ("libbpf: Implement basic zip archive parsing support")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/bpf/CA+G9fYtBnwxAWXi2+GyNByApxnf_DtP1-6+_zOKAdJKnJBexjg@mail.gmail.com/
Link: https://lore.kernel.org/bpf/20230315171550.1551603-1-deso@posteo.net
This reverts commit 6d0c4b11e743("libbpf: Poison strlcpy()").
It added the pragma poison directive to libbpf_internal.h to protect
against accidental usage of strlcpy but ended up breaking the build for
toolchains based on libcs which provide the strlcpy() declaration from
string.h (e.g. uClibc-ng). The include order which causes the issue is:
string.h,
from Iibbpf_common.h:12,
from libbpf.h:20,
from libbpf_internal.h:26,
from strset.c:9:
Fixes: 6d0c4b11e7 ("libbpf: Poison strlcpy()")
Signed-off-by: Jesus Sanchez-Palencia <jesussanp@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230309004836.2808610-1-jesussanp@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Parsing of USDT arguments is architecture-specific; on arm it is
relatively easy since registers used are r[0-10], fp, ip, sp, lr,
pc. Format is slightly different compared to aarch64; forms are
- "size @ [ reg, #offset ]" for dereferences, for example
"-8 @ [ sp, #76 ]" ; " -4 @ [ sp ]"
- "size @ reg" for register values; for example
"-4@r0"
- "size @ #value" for raw values; for example
"-8@#1"
Add support for parsing USDT arguments for ARM architecture.
To test the above changes QEMU's virt[1] board with cortex-a15
CPU was used. libbpf-bootstrap's usdt example[2] was modified to attach
to a test program with DTRACE_PROBE1/2/3/4... probes to test different
combinations.
[1] https://www.qemu.org/docs/master/system/arm/virt.html
[2] https://github.com/libbpf/libbpf-bootstrap/blob/master/examples/c/usdt.bpf.c
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230307120440.25941-3-puranjay12@gmail.com
The parse_usdt_arg() function is defined differently for each
architecture but the last part of the function is repeated
verbatim for each architecture.
Refactor parse_usdt_arg() to fill the arg_sz and then do the repeated
post-processing in parse_usdt_spec().
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230307120440.25941-2-puranjay12@gmail.com
Coverity reported a potential underflow of the offset variable used in
the find_cd() function. Switch to using a signed 64 bit integer for the
representation of offset to make sure we can never underflow.
Fixes: 1eebcb6063 ("libbpf: Implement basic zip archive parsing support")
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230307215504.837321-1-deso@posteo.net
By default, libbpf will attach the kprobe/uprobe BPF program in the
latest mode that supported by kernel. In this patch, we add the support
to let users manually attach kprobe/uprobe in legacy or perf mode.
There are 3 mode that supported by the kernel to attach kprobe/uprobe:
LEGACY: create perf event in legacy way and don't use bpf_link
PERF: create perf event with perf_event_open() and don't use bpf_link
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Biao Jiang <benbjiang@tencent.com>
Link: create perf event with perf_event_open() and use bpf_link
Link: https://lore.kernel.org/bpf/20230113093427.1666466-1-imagedong@tencent.com/
Link: https://lore.kernel.org/bpf/20230306064833.7932-2-imagedong@tencent.com
Users now can manually choose the mode with
bpf_program__attach_uprobe_opts()/bpf_program__attach_kprobe_opts().
__kptr meant to store PTR_UNTRUSTED kernel pointers inside bpf maps.
The concept felt useful, but didn't get much traction,
since bpf_rdonly_cast() was added soon after and bpf programs received
a simpler way to access PTR_UNTRUSTED kernel pointers
without going through restrictive __kptr usage.
Rename __kptr_ref -> __kptr and __kptr -> __kptr_untrusted to indicate
its intended usage.
The main goal of __kptr_untrusted was to read/write such pointers
directly while bpf_kptr_xchg was a mechanism to access refcnted
kernel pointers. The next patch will allow RCU protected __kptr access
with direct read. At that point __kptr_untrusted will be deprecated.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230303041446.3630-2-alexei.starovoitov@gmail.com
This change adds support for attaching uprobes to shared objects located
in APKs, which is relevant for Android systems where various libraries
may reside in APKs. To make that happen, we extend the syntax for the
"binary path" argument to attach to with that supported by various
Android tools:
<archive>!/<binary-in-archive>
For example:
/system/app/test-app/test-app.apk!/lib/arm64-v8a/libc++_shared.so
APKs need to be specified via full path, i.e., we do not attempt to
resolve mere file names by searching system directories.
We cannot currently test this functionality end-to-end in an automated
fashion, because it relies on an Android system being present, but there
is no support for that in CI. I have tested the functionality manually,
by creating a libbpf program containing a uretprobe, attaching it to a
function inside a shared object inside an APK, and verifying the sanity
of the returned values.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230301212308.1839139-4-deso@posteo.net
This change splits the elf_find_func_offset() function in two:
elf_find_func_offset(), which now accepts an already opened Elf object
instead of a path to a file that is to be opened, as well as
elf_find_func_offset_from_file(), which opens a binary based on a
path and then invokes elf_find_func_offset() on the Elf object. Having
this split in responsibilities will allow us to call
elf_find_func_offset() from other code paths on Elf objects that did not
necessarily come from a file on disk.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230301212308.1839139-3-deso@posteo.net
This change implements support for reading zip archives, including
opening an archive, finding an entry based on its path and name in it,
and closing it.
The code was copied from https://github.com/iovisor/bcc/pull/4440, which
implements similar functionality for bcc. The author confirmed that he
is fine with this usage and the corresponding relicensing. I adjusted it
to adhere to libbpf coding standards.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Michał Gregorczyk <michalgr@meta.com>
Link: https://lore.kernel.org/bpf/20230301212308.1839139-2-deso@posteo.net
Commit 04d58f1b26a4("libbpf: add API to get XDP/XSK supported features")
added feature_flags to struct bpf_xdp_query_opts. If a user uses
bpf_xdp_query_opts with feature_flags member, the bpf_xdp_query()
will check whether 'netdev' family exists or not in the kernel.
If it does not exist, the bpf_xdp_query() will return -ENOENT.
But 'netdev' family does not exist in old kernels as it is
introduced in the same patch set as Commit 04d58f1b26.
So old kernel with newer libbpf won't work properly with
bpf_xdp_query() api call.
To fix this issue, if the return value of
libbpf_netlink_resolve_genl_family_id() is -ENOENT, bpf_xdp_query()
will just return 0, skipping the rest of xdp feature query.
This preserves backward compatibility.
Fixes: 04d58f1b26 ("libbpf: add API to get XDP/XSK supported features")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230227224943.1153459-1-yhs@fb.com
The syscall register definitions for ARM in bpf_tracing.h doesn't define
the fifth parameter for the syscalls. Because of this some KPROBES based
selftests fail to compile for ARM architecture.
Define the fifth parameter that is passed in the R5 register (uregs[4]).
Fixes: 3a95c42d65 ("libbpf: Define arm syscall regs spec in bpf_tracing.h")
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230223095346.10129-1-puranjay12@gmail.com
These are type-safe wrappers around bpf_obj_get_info_by_fd(). They
found one problem in selftests, and are also useful for adding
Memory Sanitizer annotations.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230214231221.249277-2-iii@linux.ibm.com
The code assumes that everything that comes after nlmsgerr are nlattrs.
When calculating their size, it does not account for the initial
nlmsghdr. This may lead to accessing uninitialized memory.
Fixes: bbf48c18ee ("libbpf: add error reporting in XDP")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com
Add option to set when the perf buffer should wake up, by default the
perf buffer becomes signaled for every event that is being pushed to it.
In case of a high throughput of events it will be more efficient to wake
up only once you have X events ready to be read.
So your application can wakeup once and drain the entire perf buffer.
Signed-off-by: Jon Doron <jond@wiz.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230207081916.3398417-1-arilou@gmail.com
In a previous commit, Ubuntu kernel code version is correctly set
by retrieving the information from /proc/version_signature.
commit<5b3d72987701d51bf31823b39db49d10970f5c2d>
(libbpf: Improve LINUX_VERSION_CODE detection)
The /proc/version_signature file doesn't present in at least the
older versions of Debian distributions (eg, Debian 9, 10). The Debian
kernel has a similar issue where the release information from uname()
syscall doesn't give the kernel code version that matches what the
kernel actually expects. Below is an example content from Debian 10.
release: 4.19.0-23-amd64
version: #1 SMP Debian 4.19.269-1 (2022-12-20) x86_64
Debian reports incorrect kernel version in utsname::release returned
by uname() syscall, which in older kernels (Debian 9, 10) leads to
kprobe BPF programs failing to load due to the version check mismatch.
Fortunately, the correct kernel code version presents in the
utsname::version returned by uname() syscall in Debian kernels. This
change adds another get kernel version function to handle Debian in
addition to the previously added get kernel version function to handle
Ubuntu. Some minor refactoring work is also done to make the code more
readable.
Signed-off-by: Hao Xiang <hao.xiang@bytedance.com>
Signed-off-by: Ho-Ren (Jack) Chuang <horenchuang@bytedance.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230203234842.2933903-1-hao.xiang@bytedance.com
Extend bpf_xdp_query routine in order to get XDP/XSK supported features
of netdev over route netlink interface.
Extend libbpf netlink implementation in order to support netlink_generic
protocol.
Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Co-developed-by: Marek Majtyka <alardam@gmail.com>
Signed-off-by: Marek Majtyka <alardam@gmail.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/a72609ef4f0de7fee5376c40dbf54ad7f13bfb8d.1675245258.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
BPF_PROBE_READ_INTO() and BPF_PROBE_READ_STR_INTO() should map to
bpf_probe_read() and bpf_probe_read_str() respectively in order to work
correctly on architectures with !ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-24-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Loading programs that use bpf_usdt_arg() on s390x fails with:
; if (arg_num >= BPF_USDT_MAX_ARG_CNT || arg_num >= spec->arg_cnt)
128: (79) r1 = *(u64 *)(r10 -24) ; frame1: R1_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) R10=fp0
129: (25) if r1 > 0xb goto pc+83 ; frame1: R1_w=scalar(umax=11,var_off=(0x0; 0xf))
...
; arg_spec = &spec->args[arg_num];
135: (79) r1 = *(u64 *)(r10 -24) ; frame1: R1_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) R10=fp0
...
; switch (arg_spec->arg_type) {
139: (61) r1 = *(u32 *)(r2 +8)
R2 unbounded memory access, make sure to bounds check any such access
The reason is that, even though the C code enforces that
arg_num < BPF_USDT_MAX_ARG_CNT, the verifier cannot propagate this
constraint to the arg_spec assignment yet. Help it by forcing r1 back
to stack after comparison.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-23-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This fixes the doxygen format documentation above the
user_ring_buffer__* APIs. There has to be a newline
before the @brief, otherwise doxygen won't render them
for libbpf.readthedocs.org.
Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230126024749.522278-1-grantseltzer@gmail.com
In a prior change, the verifier was updated to support sleepable
BPF_PROG_TYPE_STRUCT_OPS programs. A caller could set the program as
sleepable with bpf_program__set_flags(), but it would be more ergonomic
and more in-line with other sleepable program types if we supported
suffixing a struct_ops section name with .s to indicate that it's
sleepable.
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125164735.785732-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Each architecture supports at least 6 syscall argument registers, so now
that specs for each architecture is defined in bpf_tracing.h, remove
unnecessary macro overrides, which previously were required to keep
existing BPF_KSYSCALL() uses compiling and working.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-26-andrii@kernel.org
Define explicit table of registers used for syscall argument passing.
Note that 7th arg is supported on 32-bit powerpc architecture, by not on
powerpc64.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-20-andrii@kernel.org
Define explicit table of registers used for syscall argument passing.
We need PT_REGS_PARM1_[CORE_]SYSCALL macros overrides, similarly to
s390x, due to orig_x0 not being present in UAPI's pt_regs, so we need to
utilize BPF CO-RE and custom pt_regs___arm64 definition.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Link: https://lore.kernel.org/bpf/20230120200914.3008030-18-andrii@kernel.org
Define explicit table of registers used for syscall argument passing.
Note that we need custom overrides for PT_REGS_PARM1_[CORE_]SYSCALL
macros due to the need to use BPF CO-RE and custom local pt_regs
definitions to fetch orig_gpr2, storing 1st argument.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # s390x
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-16-andrii@kernel.org
Define explicit table of registers used for syscall argument passing.
Remove now unnecessary overrides of PT_REGS_PARM5_[CORE_]SYSCALL macros.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-14-andrii@kernel.org
Set up generic support in bpf_tracing.h for up to 7 syscall arguments
tracing with BPF_KSYSCALL, which seems to be the limit according to
syscall(2) manpage. Also change the way that syscall convention is
specified to be more explicit. Subsequent patches will adjust and define
proper per-architecture syscall conventions.
__PT_PARM1_SYSCALL_REG through __PT_PARM6_SYSCALL_REG is added
temporarily to keep everything working before each architecture has
syscall reg tables defined. They will be removed afterwards.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Link: https://lore.kernel.org/bpf/20230120200914.3008030-13-andrii@kernel.org
Add BPF_UPROBE and BPF_URETPROBE macros, aliased to BPF_KPROBE and
BPF_KRETPROBE, respectively. This makes uprobe-based BPF program code
much less confusing, especially to people new to tracing, at no cost in
terms of maintainability. We'll use this macro in selftests in
subsequent patch.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-11-andrii@kernel.org
Add PARM6 through PARM8 definitions. Also fix frame pointer (FP)
register definition. Also leave a link to where to find ABI spec.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-9-andrii@kernel.org
Add PARM6 through PARM8 definitions for RISC V (riscv) arch. Leave the
link for ABI doc for future reference.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Pu Lehui <pulehui@huawei.com> # RISC-V
Link: https://lore.kernel.org/bpf/20230120200914.3008030-8-andrii@kernel.org
Add definitions of PARM6 through PARM8 for powerpc architecture. Add
also a link to a functiona call sequence documentation for future reference.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-6-andrii@kernel.org
Add registers for PARM6 through PARM8. Add a link to an ABI. We don't
distinguish between O32, N32, and N64, so document that we assume N64
right now.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-5-andrii@kernel.org
Remove invalid support for PARM5 on 32-bit arm, as per ABI. Add three
more argument registers for arm64. Also leave links to ABI specs for
future reference.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Link: https://lore.kernel.org/bpf/20230120200914.3008030-4-andrii@kernel.org
Add r9 as register containing 6th argument on x86-64 architecture, as
per its ABI. Add also a link to a page describing ABI for easier future
reference.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-3-andrii@kernel.org
Add BPF_KPROBE() and PT_REGS_PARMx() support for up to 8 arguments, if
target architecture supports this. Currently all architectures are
limited to only 5 register-placed arguments, which is limiting even on
x86-64.
This patch adds generic macro machinery to support up to 8 arguments
both when explicitly fetching it from pt_regs through PT_REGS_PARMx()
macros, as well as more ergonomic access in BPF_KPROBE().
Also, for i386 architecture we now don't have to define fake PARM4 and
PARM5 definitions, they will be generically substituted, just like for
PARM6 through PARM8.
Subsequent patches will fill out architecture-specific definitions,
where appropriate.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com> # arm64
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # s390x
Link: https://lore.kernel.org/bpf/20230120200914.3008030-2-andrii@kernel.org
'.' is not allowed in the event name of kprobe. Therefore, we will get a
EINVAL if the kernel function name has a '.' in legacy kprobe attach
case, such as 'icmp_reply.constprop.0'.
In order to adapt this case, we need to replace the '.' with other char
in gen_kprobe_legacy_event_name(). And I use '_' for this propose.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20230113093427.1666466-1-imagedong@tencent.com
As BPF_F_MMAPABLE flag is now conditionnaly set (by map_is_mmapable),
it should not be toggled but disabled if not supported by kernel.
Fixes: 4fcac46c7e ("libbpf: only add BPF_F_MMAPABLE flag for data maps with global vars")
Signed-off-by: Ludovic L'Hours <ludovic.lhours@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230108182018.24433-1-ludovic.lhours@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Since commit 9fc205b413b3("libbpf: Add sane strncpy alternative and use
it internally") introduce libbpf_strlcpy(), thus add strlcpy() to a poison
list to prevent accidental use of it.
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/tencent_5695A257C4D16B4413036BA1DAACDECB0B07@qq.com
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
bpf-next 2023-01-04
We've added 45 non-merge commits during the last 21 day(s) which contain
a total of 50 files changed, 1454 insertions(+), 375 deletions(-).
The main changes are:
1) Fixes, improvements and refactoring of parts of BPF verifier's
state equivalence checks, from Andrii Nakryiko.
2) Fix a few corner cases in libbpf's BTF-to-C converter in particular
around padding handling and enums, also from Andrii Nakryiko.
3) Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better
support decap on GRE tunnel devices not operating in collect metadata,
from Christian Ehrig.
4) Improve x86 JIT's codegen for PROBE_MEM runtime error checks,
from Dave Marchevsky.
5) Remove the need for trace_printk_lock for bpf_trace_printk
and bpf_trace_vprintk helpers, from Jiri Olsa.
6) Add proper documentation for BPF_MAP_TYPE_SOCK{MAP,HASH} maps,
from Maryam Tahhan.
7) Improvements in libbpf's btf_parse_elf error handling, from Changbin Du.
8) Bigger batch of improvements to BPF tracing code samples,
from Daniel T. Lee.
9) Add LoongArch support to libbpf's bpf_tracing helper header,
from Hengqi Chen.
10) Fix a libbpf compiler warning in perf_event_open_probe on arm32,
from Khem Raj.
11) Optimize bpf_local_storage_elem by removing 56 bytes of padding,
from Martin KaFai Lau.
12) Use pkg-config to locate libelf for resolve_btfids build,
from Shen Jiamin.
13) Various libbpf improvements around API documentation and errno
handling, from Xin Liu.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (45 commits)
libbpf: Return -ENODATA for missing btf section
libbpf: Add LoongArch support to bpf_tracing.h
libbpf: Restore errno after pr_warn.
libbpf: Added the description of some API functions
libbpf: Fix invalid return address register in s390
samples/bpf: Use BPF_KSYSCALL macro in syscall tracing programs
samples/bpf: Fix tracex2 by using BPF_KSYSCALL macro
samples/bpf: Change _kern suffix to .bpf with syscall tracing program
samples/bpf: Use vmlinux.h instead of implicit headers in syscall tracing program
samples/bpf: Use kyscall instead of kprobe in syscall tracing program
bpf: rename list_head -> graph_root in field info types
libbpf: fix errno is overwritten after being closed.
bpf: fix regs_exact() logic in regsafe() to remap IDs correctly
bpf: perform byte-by-byte comparison only when necessary in regsafe()
bpf: reject non-exact register type matches in regsafe()
bpf: generalize MAYBE_NULL vs non-MAYBE_NULL rule
bpf: reorganize struct bpf_reg_state fields
bpf: teach refsafe() to take into account ID remapping
bpf: Remove unused field initialization in bpf's ctl_table
selftests/bpf: Add jit probe_mem corner case tests to s390x denylist
...
====================
Link: https://lore.kernel.org/r/20230105000926.31350-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As discussed before, return -ENODATA (No data available) would be more
meaningful than ENOENT (No such file or directory).
Suggested-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221231151436.6541-1-changbin.du@gmail.com
pr_warn calls into user-provided callback, which can clobber errno, so
`errno = saved_errno` should happen after pr_warn.
Fixes: 0745324562 ("libbpf: fix errno is overwritten after being closed.")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Currently, many API functions are not described in the document.
Add add API description of the following four API functions:
- libbpf_set_print;
- bpf_object__open;
- bpf_object__load;
- bpf_object__close.
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221224112058.12038-1-liuxin350@huawei.com
There is currently an invalid register mapping in the s390 return
address register. As the manual[1] states, the return address can be
found at r14. In bpf_tracing.h, the s390 registers were named
gprs(general purpose registers). This commit fixes the problem by
correcting the mistyped mapping.
[1]: https://uclibc.org/docs/psABI-s390x.pdf#page=14
Fixes: 3cc31d7940 ("libbpf: Normalize PT_REGS_xxx() macro definitions")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221224071527.2292-7-danieltimlee@gmail.com
In the ensure_good_fd function, if the fcntl function succeeds but
the close function fails, ensure_good_fd returns a normal fd and
sets errno, which may cause users to misunderstand. The close
failure is not a serious problem, and the correct FD has been
handed over to the upper-layer application. Let's restore errno here.
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Link: https://lore.kernel.org/r/20221223133618.10323-1-liuxin350@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Bump current version for new development cycle to v1.2.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20221221180049.853365-1-andrii@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Show the real problem instead of just saying "No such file or directory".
Now will print below info:
libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux
Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221217223509.88254-2-changbin.du@gmail.com
Clang warns on 32-bit ARM on this comparision:
libbpf.c:10497:18: error: result of comparison of constant 4294967296 with expression of type 'size_t' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare]
if (ref_ctr_off >= (1ULL << PERF_UPROBE_REF_CTR_OFFSET_BITS))
~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Typecast ref_ctr_off to __u64 in the check conditional, it is false on
32bit anyways.
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221219191526.296264-1-raj.khem@gmail.com
To resolve a trivial merge conflict with c302378bc1 ("libbpf:
Hashmap interface update to allow both long and void* keys/values"),
where a function present upstream was removed in the perf tools
development tree.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix bug in btf_dump's logic of determining if a given struct type is
packed or not. The notion of "natural alignment" is not needed and is
even harmful in this case, so drop it altogether. The biggest difference
in btf_is_struct_packed() compared to its original implementation is
that we don't really use btf__align_of() to determine overall alignment
of a struct type (because it could be 1 for both packed and non-packed
struct, depending on specifci field definitions), and just use field's
actual alignment to calculate whether any field is requiring packing or
struct's size overall necessitates packing.
Add two simple test cases that demonstrate the difference this change
would make.
Fixes: ea2ce1ba99 ("libbpf: Fix BTF-to-C converter's padding logic")
Reported-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20221215183605.4149488-1-andrii@kernel.org
Turns out that btf_dump API doesn't handle a bunch of tricky corner
cases, as reported by Per, and further discovered using his testing
Python script ([0]).
This patch revamps btf_dump's padding logic significantly, making it
more correct and also avoiding unnecessary explicit padding, where
compiler would pad naturally. This overall topic turned out to be very
tricky and subtle, there are lots of subtle corner cases. The comments
in the code tries to give some clues, but comments themselves are
supposed to be paired with good understanding of C alignment and padding
rules. Plus some experimentation to figure out subtle things like
whether `long :0;` means that struct is now forced to be long-aligned
(no, it's not, turns out).
Anyways, Per's script, while not completely correct in some known
situations, doesn't show any obvious cases where this logic breaks, so
this is a nice improvement over the previous state of this logic.
Some selftests had to be adjusted to accommodate better use of natural
alignment rules, eliminating some unnecessary padding, or changing it to
`type: 0;` alignment markers.
Note also that for when we are in between bitfields, we emit explicit
bit size, while otherwise we use `: 0`, this feels much more natural in
practice.
Next patch will add few more test cases, found through randomized Per's
script.
[0] https://lore.kernel.org/bpf/85f83c333f5355c8ac026f835b18d15060725fcb.camel@ericsson.com/
Reported-by: Per Sundström XP <per.xp.sundstrom@ericsson.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221212211505.558851-6-andrii@kernel.org
btf__align_of() is supposed to be return alignment requirement of
a requested BTF type. For STRUCT/UNION it doesn't always return correct
value, because it calculates alignment only based on field types. But
for packed structs this is not enough, we need to also check field
offsets and struct size. If field offset isn't aligned according to
field type's natural alignment, then struct must be packed. Similarly,
if struct size is not a multiple of struct's natural alignment, then
struct must be packed as well.
This patch fixes this issue precisely by additionally checking these
conditions.
Fixes: 3d208f4ca1 ("libbpf: Expose btf__align_of() API")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221212211505.558851-5-andrii@kernel.org
Turns out C allows to force enum to be 1-byte or 8-byte explicitly using
mode(byte) or mode(word), respecticely. Linux sources are using this in
some cases. This is imporant to handle correctly, as enum size
determines corresponding fields in a struct that use that enum type. And
if enum size is incorrect, this will lead to invalid struct layout. So
add mode(byte) and mode(word) attribute support to btf_dump APIs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221212211505.558851-3-andrii@kernel.org
btf_dump APIs emit unnecessary tabs when emitting struct/union
definition that fits on the single line. Before this patch we'd get:
struct blah {<tab>};
This patch fixes this and makes sure that we get more natural:
struct blah {};
Fixes: 44a726c3f2 ("bpftool: Print newline before '}' for struct with padding only fields")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221212211505.558851-2-andrii@kernel.org
This is a small improvement in libbpf_strerror. When libbpf_strerror
is used to obtain the system error description, if the length of the
buf is insufficient, libbpf_sterror returns ERANGE and sets errno to
ERANGE.
However, this processing is not performed when the error code
customized by libbpf is obtained. Make some minor improvements here,
return -ERANGE and set errno to ERANGE when buf is not enough for
custom description.
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221210082045.233697-1-liuxin350@huawei.com
Parse USDT arguments like "8@(%rsp)" on x86. These are emmited by
SystemTap. The argument syntax is similar to the existing "memory
dereference case" but the offset left out as it's zero (i.e. read
the value from the address in the register). We treat it the same
as the the "memory dereference case", but set the offset to 0.
I've tested that this fixes the "unrecognized arg #N spec: 8@(%rsp).."
error I've run into when attaching to a probe with such an argument.
Attaching and reading the correct argument values works.
Something similar might be needed for the other supported
architectures.
[0] Closes: https://github.com/libbpf/libbpf/issues/559
Signed-off-by: Timo Hunziker <timo.hunziker@gmx.ch>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221203123746.2160-1-timo.hunziker@eclipso.ch
Current libbpf Makefile does not contain the help command, which
is inconvenient to use. Similar to the Makefile help command of the
perf, a help command is provided to list the commands supported by
libbpf make and the functions of the commands.
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221202081738.128513-1-liuxin350@huawei.com
C++ enum forward declarations are fundamentally not compatible with pure
C enum definitions, and so libbpf's use of `enum bpf_stats_type;`
forward declaration in libbpf/bpf.h public API header is causing C++
compilation issues.
More details can be found in [0], but it comes down to C++ supporting
enum forward declaration only with explicitly specified backing type:
enum bpf_stats_type: int;
In C (and I believe it's a GCC extension also), such forward declaration
is simply:
enum bpf_stats_type;
Further, in Linux UAPI this enum is defined in pure C way:
enum bpf_stats_type { BPF_STATS_RUN_TIME = 0; }
And even though in both cases backing type is int, which can be
confirmed by looking at DWARF information, for C++ compiler actual enum
definition and forward declaration are incompatible.
To eliminate this problem, for C++ mode define input argument as int,
which makes enum unnecessary in libbpf public header. This solves the
issue and as demonstrated by next patch doesn't cause any unwanted
compiler warnings, at least with default warnings setting.
[0] https://stackoverflow.com/questions/42766839/c11-enum-forward-causes-underlying-type-mismatch
[1] Closes: https://github.com/libbpf/libbpf/issues/249
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221130200013.2997831-1-andrii@kernel.org
Currently LLVM fails to recognize .data.* as data section and defaults to .text
section. Later BPF backend tries to emit 4-byte NOP instruction which doesn't
exist in BPF ISA and aborts.
The fix for LLVM is pending:
https://reviews.llvm.org/D138477
While waiting for the fix lets workaround the linked_list test case
by using .bss.* prefix which is properly recognized by LLVM as BSS section.
Fix libbpf to support .bss. prefix and adjust tests.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The perf build makes the install_headers target, however, as there is
no action for this target a warning is always produced of:
make[3]: Nothing to be done for 'install_headers'.
Solve this by adding a display of 'INSTALL libbpf_headers'.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221117004356.279422-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Coverity is reporting that btf_dump_name_dups() doesn't check return
result of hashmap__find() call. This is intentional, so make it explicit
with (void) cast.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221117192824.4093553-1-andrii@kernel.org
The top two bits of size are used as busy and discard flags, so reject
the reservation that has any of these special bits in the size. With the
addition of validity check, these is also no need to check whether or
not total_size is overflowed.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221116072351.1168938-5-houtao@huaweicloud.com
Similar with the overflow problem on ringbuf mmap, in user_ringbuf_map()
2 * max_entries may overflow u32 when mapping writeable region.
Fixing it by casting the size of writable mmap region into a __u64 and
checking whether or not there will be overflow during mmap.
Fixes: b66ccae01f ("bpf: Add libbpf logic for user-space ring buffer")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221116072351.1168938-4-houtao@huaweicloud.com
