Allow bpf object feat_cache assignment in BPF selftests
to simulate missing features via inclusion of libbpf_internal.h
and use of bpf_object_set_feat_cache() and bpf_object__sanitize_btf() to
test BTF sanitization for cases where missing features are simulated.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/r/20260408165735.843763-2-alan.maguire@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
CO-RE accessor strings are colon-separated indices that describe a path
from a root BTF type to a target field, e.g. "0:1:2" walks through
nested struct members. bpf_core_parse_spec() parses each component with
sscanf("%d"), so negative values like -1 are silently accepted. The
subsequent bounds checks (access_idx >= btf_vlen(t)) only guard the
upper bound and always pass for negative values because C integer
promotion converts the __u16 btf_vlen result to int, making the
comparison (int)(-1) >= (int)(N) false for any positive N.
When -1 reaches btf_member_bit_offset() it gets cast to u32 0xffffffff,
producing an out-of-bounds read far past the members array. A crafted
BPF program with a negative CO-RE accessor on any struct that exists in
vmlinux BTF (e.g. task_struct) crashes the kernel deterministically
during BPF_PROG_LOAD on any system with CONFIG_DEBUG_INFO_BTF=y
(default on major distributions). The bug is reachable with CAP_BPF:
BUG: unable to handle page fault for address: ffffed11818b6626
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
Oops: Oops: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 85 Comm: poc Not tainted 7.0.0-rc6 #18 PREEMPT(full)
RIP: 0010:bpf_core_parse_spec (tools/lib/bpf/relo_core.c:354)
RAX: 00000000ffffffff
Call Trace:
<TASK>
bpf_core_calc_relo_insn (tools/lib/bpf/relo_core.c:1321)
bpf_core_apply (kernel/bpf/btf.c:9507)
check_core_relo (kernel/bpf/verifier.c:19475)
bpf_check (kernel/bpf/verifier.c:26031)
bpf_prog_load (kernel/bpf/syscall.c:3089)
__sys_bpf (kernel/bpf/syscall.c:6228)
</TASK>
CO-RE accessor indices are inherently non-negative (struct member index,
array element index, or enumerator index), so reject them immediately
after parsing.
Fixes: ddc7c30426 ("libbpf: implement BPF CO-RE offset relocation algorithm")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Acked-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/20260404161221.961828-2-bestswngs@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_program__attach_kprobe_opts() documents single-kprobe attach
through func_name, with an optional offset. For the PMU-based path,
func_name = NULL with an absolute address in offset already works as
well, but that is not described in the API.
This commit clarifies this existing non-legacy behavior. For PMU-based
attach, callers can use func_name = NULL with an absolute address in
offset as the raw-address form. For legacy tracefs/debugfs kprobes,
reject this form explicitly.
Signed-off-by: Hoyeon Lee <hoyeon.lee@suse.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20260401143116.185049-3-hoyeon.lee@suse.com
perf_event_open_probe() and perf_event_{k,u}probe_open_legacy() helpers
are returning negative error codes directly on failure. This commit
changes bpf_program__attach_{k,u}probe_opts() to use those return
values directly instead of re-reading possibly changed errno.
Signed-off-by: Hoyeon Lee <hoyeon.lee@suse.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20260401143116.185049-2-hoyeon.lee@suse.com
Align bpf_program__clone() with bpf_object_load_prog() by gating
BTF func/line info on FEAT_BTF_FUNC kernel support, and resolve
caller-provided prog_btf_fd before checking obj->btf so that callers
with their own BTF can use clone() even when the object has no BTF
loaded.
While at it, treat func_info and line_info fields as atomic groups
to prevent mismatches between pointer and count from different sources.
Move bpf_program__clone() to libbpf 1.8.
Fixes: 970bd2dced ("libbpf: Introduce bpf_program__clone()")
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260401151640.356419-1-mykyta.yatsenko5@gmail.com
Add a FEAT_BTF_LAYOUT feature check which checks if the
kernel supports BTF layout information. Also sanitize
BTF if it contains layout data but the kernel does not
support it. The sanitization requires rewriting raw
BTF data to update the header and eliminate the layout
section (since it lies between the types and strings),
so refactor sanitization to do the raw BTF retrieval
and creation of updated BTF, returning that new BTF
on success.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260326145444.2076244-7-alan.maguire@oracle.com
BTF parsing can use layout to navigate unknown kinds, so
btf_validate_type() should take layout information into
account to avoid failure when an unrecognized kind is met.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260326145444.2076244-6-alan.maguire@oracle.com
Support encoding of BTF layout data via btf__new_empty_opts().
Current supported opts are base_btf and add_layout.
Layout information is maintained in btf.c in the layouts[] array;
when BTF is created with the add_layout option it represents the
current view of supported BTF kinds.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260326145444.2076244-5-alan.maguire@oracle.com
This allows BTF parsing to proceed even if we do not know the
kind. Fall back to base BTF layout if layout information is
not in split BTF.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260326145444.2076244-4-alan.maguire@oracle.com
Support reading in layout fixing endian issues on reading;
also support writing layout section to raw BTF object.
There is not yet an API to populate the layout with meaningful
information.
As part of this, we need to consider multiple valid BTF header
sizes; the original or the layout-extended headers.
So to support this, the "struct btf" representation is modified
to contain a "struct btf_header" and we copy the valid
portion from the raw data to it; this means we can always safely
check fields like btf->hdr.layout_len .
Note if parsed-in BTF has extra header information beyond
sizeof(struct btf_header) - if so we make that BTF ineligible
for modification by setting btf->has_hdr_extra .
Ensure that we handle endianness issues for BTF layout section,
though currently only field that needs this (flags) is unused.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260326145444.2076244-3-alan.maguire@oracle.com
Add bpf_program__clone() API that loads a single BPF program from a
prepared BPF object into the kernel, returning a file descriptor owned
by the caller.
After bpf_object__prepare(), callers can use bpf_program__clone() to
load individual programs with custom bpf_prog_load_opts, instead of
loading all programs at once via bpf_object__load(). Non-zero fields in
opts override the defaults derived from the program and object
internals; passing NULL opts populates everything automatically.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260317-veristat_prepare-v4-1-74193d4cc9d9@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Detect exact function names (no wildcards) in
bpf_program__attach_kprobe_multi_opts() and bypass kallsyms parsing,
passing the symbol directly to the kernel via syms[] array. This
benefits all callers, not just kprobe.session.
When the pattern contains no '*' or '?' characters, set syms to point
directly at the pattern string and cnt to 1, skipping the expensive
/proc/kallsyms or available_filter_functions parsing (~150ms per
function).
Error code normalization: the fast path returns ESRCH from kernel's
ftrace_lookup_symbols(), while the slow path returns ENOENT from
userspace kallsyms parsing. Convert ESRCH to ENOENT in the
bpf_link_create error path to maintain API consistency - both paths
now return identical error codes for "symbol not found".
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260302200837.317907-2-andrey.grodzovsky@crowdstrike.com
btf__add_btf() currently rejects split BTF sources with -ENOTSUP.
This prevents merging types from multiple kernel module BTFs that
are all split against the same vmlinux base.
Extend btf__add_btf() to handle split BTF sources by:
- Replacing the blanket -ENOTSUP with a validation that src and dst
share the same base BTF pointer when both are split, returning
-EOPNOTSUPP on mismatch.
- Computing src_start_id from the source's base to distinguish base
type ID references (which must remain unchanged) from split type
IDs (which must be remapped to new positions in the destination).
- Using src_btf->nr_types instead of btf__type_cnt()-1 for the type
count, which is correct for both split and non-split sources.
- Skipping base string offsets (< start_str_off) during the string
rewrite loop, mirroring the type ID skip pattern. Since src and
dst share the same base BTF, base string offsets are already valid
and need no remapping.
For non-split sources the behavior is identical: src_start_id is 1,
the type_id < 1 guard is never true (VOID is already skipped), and
the remapping formula reduces to the original. start_str_off is 0
so no string offsets are skipped.
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/c00216ed48cf7897078d9645679059d5ebf42738.1772657690.git.josef@toxicpanda.com
Adding support to detect nop,nop5 instructions combo for usdt probe
by checking on probe's following nop5 instruction.
When the nop,nop5 combo is detected together with uprobe syscall,
we can place the probe on top of nop5 and get it optimized.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20260224103915.1369690-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
An issue was reported that building BPF program which includes both
vmlinux.h and bpf_helpers.h from libbpf fails due to conflicting
declarations of bpf_stream_vprintk().
Remove the extern declaration from bpf_helpers.h to address this.
In order to use bpf_stream_printk() macro, BPF programs are expected
to either include vmlinux.h of the kernel they are targeting, or add
their own extern declaration.
Reported-by: Luca Boccassi <luca.boccassi@gmail.com>
Closes: https://github.com/libbpf/libbpf/issues/947
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/r/20260218215651.2057673-3-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Netlink requires that the recv buffer used during dumps is at least
min(PAGE_SIZE, 8k) (see the man page). Otherwise the messages will
get truncated. Make sure bpftool follows this requirement, avoid
missing information on systems with large pages.
Acked-by: Quentin Monnet <qmo@kernel.org>
Fixes: 7084566a23 ("tools/bpftool: Remove libbpf_internal.h usage in bpftool")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20260217194150.734701-1-kuba@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 728ff16791 ("libbpf: Add gating for arena globals relocation feature")
adds a feature gate check that loads a map and BPF program to
test the running kernel supports large direct offsets for LDIMM64
instructions. This check is currently used to calculate arena symbol
offsets during bpf_object__collect_relos, itself called by
bpf_object_open.
However, the program calling bpf_object_open may not have the permissions to
load maps and programs. This is the case with the BPF selftests, where
bpftool is invoked at compilation time during skeleton generation. This
causes errors as the feature gate unexpectedly fails with -EPERM.
Avoid this by moving all the use of the FEAT_LDIMM64_FULL_RANGE_OFF feature gate
to BPF object preparation time instead.
Fixes: 728ff16791 ("libbpf: Add gating for arena globals relocation feature")
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260217204345.548648-3-emil@etsalapatis.com
Commit 728ff16791 uses a PROG_TYPE_TRACEPOINT BPF test program to
check whether the running kernel supports large LDIMM64 offsets. The
feature gate incorrectly assumes that the program will fail at
verification time with one of two messages, depending on whether the
feature is supported by the running kernel. However,
PROG_TYPE_TRACEPOINT programs may fail to load before verification even
starts, e.g., if the shell does not have the appropriate capabilities.
Use a BPF_PROG_TYPE_SOCKET_FILTER program for the feature gate instead.
Also fix two minor issues. First, ensure the log buffer for the test is
initialized: Failing program load before verification led to libbpf dumping
uninitialized data to stdout. Also, ensure that close() is only called
for program_fd in the probe if the program load actually succeeded. The
call was currently failing silently with -EBADF most of the time.
Fixes: 728ff16791 ("libbpf: Add gating for arena globals relocation feature")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260217204345.548648-2-emil@etsalapatis.com
Fix bpf_linker__add_buf()'s logic of copying data from memory buffer into
memfd. In the event of short write not writing entire buf_sz bytes into memfd
file, we'll append bytes from the beginning of buf *again* (corrupting ELF
file contents) instead of correctly appending the rest of not-yet-read buf
contents.
Closes: https://github.com/libbpf/libbpf/issues/945
Fixes: 6d5e5e5d7c ("libbpf: Extend linker API to support in-memory ELF files")
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20260209230134.3530521-1-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add feature gating for the arena globals relocation introduced in
commit c1f61171d4. The commit depends on a previous commit in the
same patchset that is absent from older kernels
(12a1fe6e12 "bpf/verifier: Do not limit maximum direct offset into arena map").
Without this commit, arena globals relocation with arenas >= 512MiB
fails to load and breaks libbpf's backwards compatibility.
Introduce a libbpf feature to check whether the running kernel allows for
full range ldimm64 offset, and only relocate arena globals if it does.
Fixes: c1f61171d4 ("libbpf: Move arena globals to the end of the arena")
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260210184532.255475-1-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Implement bpf_stream_vprintk with an implicit bpf_prog_aux argument,
and remote bpf_stream_vprintk_impl from the kernel.
Update the selftests to use the new API with implicit argument.
bpf_stream_vprintk macro is changed to use the new bpf_stream_vprintk
kfunc, and the extern definition of bpf_stream_vprintk_impl is
replaced accordingly.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/r/20260120222638.3976562-11-ihor.solodrai@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Calling the str_is_empty function to clarify the code and
no functional changes are introduced.
Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260109130003.3313716-12-dolinux.peng@gmail.com
This patch checks whether the BTF is sorted by name in ascending
order. If sorted, binary search will be used when looking up types.
Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260109130003.3313716-6-dolinux.peng@gmail.com
This patch introduces binary search optimization for BTF type lookups
when the BTF instance contains sorted types.
The optimization significantly improves performance when searching for
types in large BTF instances with sorted types. For unsorted BTF, the
implementation falls back to the original linear search.
Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260109130003.3313716-5-dolinux.peng@gmail.com
Introduce btf__permute() API to allow in-place rearrangement of BTF types.
This function reorganizes BTF type order according to a provided array of
type IDs, updating all type references to maintain consistency.
Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260109130003.3313716-2-dolinux.peng@gmail.com
When dumping bitfield data, btf_dump_get_bitfield_value() reads data
based on the underlying type's size (t->size). However, it does not
verify that the provided data buffer (data_sz) is large enough to
contain these bytes.
If btf_dump__dump_type_data() is called with a buffer smaller than
the type's size, this leads to an out-of-bounds read. This was
confirmed by AddressSanitizer in the linked issue.
Fix this by ensuring we do not read past the provided data_sz limit.
Fixes: a1d3cc3c5e ("libbpf: Avoid use of __int128 in typed dump display")
Reported-by: Harrison Green <harrisonmichaelgreen@gmail.com>
Suggested-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Varun R Mallya <varunrmallya@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260106233527.163487-1-varunrmallya@gmail.com
Closes: https://github.com/libbpf/libbpf/issues/928
Add libbpf support for the BPF_F_CPU flag for percpu maps by embedding the
cpu info into the high 32 bits of:
1. **flags**: bpf_map_lookup_elem_flags(), bpf_map__lookup_elem(),
bpf_map_update_elem() and bpf_map__update_elem()
2. **opts->elem_flags**: bpf_map_lookup_batch() and
bpf_map_update_batch()
And the flag can be BPF_F_ALL_CPUS, but cannot be
'BPF_F_CPU | BPF_F_ALL_CPUS'.
Behavior:
* If the flag is BPF_F_ALL_CPUS, the update is applied across all CPUs.
* If the flag is BPF_F_CPU, it updates value only to the specified CPU.
* If the flag is BPF_F_CPU, lookup value only from the specified CPU.
* lookup does not support BPF_F_ALL_CPUS.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/r/20260107022022.12843-7-leon.hwang@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Arena globals are currently placed at the beginning of the arena
by libbpf. This is convenient, but prevents users from reserving
guard pages in the beginning of the arena to identify NULL pointer
dereferences. Adjust the load logic to place the globals at the
end of the arena instead.
Also modify bpftool to set the arena pointer in the program's BPF
skeleton to point to the globals. Users now call bpf_map__initial_value()
to find the beginning of the arena mapping and use the arena pointer
in the skeleton to determine which part of the mapping holds the
arena globals and which part is free.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20251216173325.98465-5-emil@etsalapatis.com
The symbols' relocation offsets in BPF are stored in an int field,
but cannot actually be negative. When in the next patch libbpf relocates
globals to the end of the arena, it is also possible to have valid
offsets > 2GiB that are used to calculate the final relo offsets.
Avoid accidentally interpreting large offsets as negative by turning
the sym_off field unsigned.
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20251216173325.98465-4-emil@etsalapatis.com
We have seen a number of issues like [1]; failures to deduplicate
key kernel data structures like task_struct. These are often hard
to debug from pahole even with verbose output, especially when
identity/equivalence checks fail deep in a nested struct comparison.
Here we add debug messages of the form
libbpf: STRUCT 'task_struct' size=2560 vlen=194 cand_id[54222] canon_id[102820] shallow-equal but not equiv for field#23 'sched_class': 0
These will be emitted during dedup from pahole when --verbose/-V
is specified. This greatly helps identify exactly where dedup
failures are experienced.
[1] https://lore.kernel.org/bpf/b8e8b560-bce5-414b-846d-0da6d22a9983@oracle.com/
Changes since v1:
- updated debug messages to refer to shallow-equal, added ids (Andrii)
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20251203191507.55565-1-alan.maguire@oracle.com
-----BEGIN PGP SIGNATURE-----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=kaCJ
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Convert selftests/bpf/test_tc_edt and test_tc_tunnel from .sh to
test_progs runner (Alexis Lothoré)
- Convert selftests/bpf/test_xsk to test_progs runner (Bastien
Curutchet)
- Replace bpf memory allocator with kmalloc_nolock() in
bpf_local_storage (Amery Hung), and in bpf streams and range tree
(Puranjay Mohan)
- Introduce support for indirect jumps in BPF verifier and x86 JIT
(Anton Protopopov) and arm64 JIT (Puranjay Mohan)
- Remove runqslower bpf tool (Hoyeon Lee)
- Fix corner cases in the verifier to close several syzbot reports
(Eduard Zingerman, KaFai Wan)
- Several improvements in deadlock detection in rqspinlock (Kumar
Kartikeya Dwivedi)
- Implement "jmp" mode for BPF trampoline and corresponding
DYNAMIC_FTRACE_WITH_JMP. It improves "fexit" program type performance
from 80 M/s to 136 M/s. With Steven's Ack. (Menglong Dong)
- Add ability to test non-linear skbs in BPF_PROG_TEST_RUN (Paul
Chaignon)
- Do not let BPF_PROG_TEST_RUN emit invalid GSO types to stack (Daniel
Borkmann)
- Generalize buildid reader into bpf_dynptr (Mykyta Yatsenko)
- Optimize bpf_map_update_elem() for map-in-map types (Ritesh
Oedayrajsingh Varma)
- Introduce overwrite mode for BPF ring buffer (Xu Kuohai)
* tag 'bpf-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (169 commits)
bpf: optimize bpf_map_update_elem() for map-in-map types
bpf: make kprobe_multi_link_prog_run always_inline
selftests/bpf: do not hardcode target rate in test_tc_edt BPF program
selftests/bpf: remove test_tc_edt.sh
selftests/bpf: integrate test_tc_edt into test_progs
selftests/bpf: rename test_tc_edt.bpf.c section to expose program type
selftests/bpf: Add success stats to rqspinlock stress test
rqspinlock: Precede non-head waiter queueing with AA check
rqspinlock: Disable spinning for trylock fallback
rqspinlock: Use trylock fallback when per-CPU rqnode is busy
rqspinlock: Perform AA checks immediately
rqspinlock: Enclose lock/unlock within lock entry acquisitions
bpf: Remove runqslower tool
selftests/bpf: Remove usage of lsm/file_alloc_security in selftest
bpf: Disable file_alloc_security hook
bpf: check for insn arrays in check_ptr_alignment
bpf: force BPF_F_RDONLY_PROG on insn array creation
bpf: Fix exclusive map memory leak
selftests/bpf: Make CS length configurable for rqspinlock stress test
selftests/bpf: Add lock wait time stats to rqspinlock stress test
...
- Provide a new interface for dynamic configuration and deconfiguration of
hotplug memory, allowing with and without memmap_on_memory support. This
makes the way memory hotplug is handled on s390 much more similar to
other architectures
- Remove compat support. There shouldn't be any compat user space around
anymore, therefore get rid of a lot of code which also doesn't need to be
tested anymore
- Add stackprotector support. GCC 16 will get new compiler options, which
allow to generate code required for kernel stackprotector support
- Merge pai_crypto and pai_ext PMU drivers into a new driver. This removes
a lot of duplicated code. The new driver is also extendable and allows
to support new PMUs
- Add driver override support for AP queues
- Rework and extend zcrypt and AP trace events to allow for tracing of
crypto requests
- Support block sizes larger than 65535 bytes for CCW tape devices
- Since the rework of the virtual kernel address space the module area and
the kernel image are within the same 4GB area. This eliminates the need
of weak per cpu variables. Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
- Various other small improvements and fixes
-----BEGIN PGP SIGNATURE-----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=CNrb
-----END PGP SIGNATURE-----
Merge tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:
- Provide a new interface for dynamic configuration and deconfiguration
of hotplug memory, allowing with and without memmap_on_memory
support. This makes the way memory hotplug is handled on s390 much
more similar to other architectures
- Remove compat support. There shouldn't be any compat user space
around anymore, therefore get rid of a lot of code which also doesn't
need to be tested anymore
- Add stackprotector support. GCC 16 will get new compiler options,
which allow to generate code required for kernel stackprotector
support
- Merge pai_crypto and pai_ext PMU drivers into a new driver. This
removes a lot of duplicated code. The new driver is also extendable
and allows to support new PMUs
- Add driver override support for AP queues
- Rework and extend zcrypt and AP trace events to allow for tracing of
crypto requests
- Support block sizes larger than 65535 bytes for CCW tape devices
- Since the rework of the virtual kernel address space the module area
and the kernel image are within the same 4GB area. This eliminates
the need of weak per cpu variables. Get rid of
ARCH_MODULE_NEEDS_WEAK_PER_CPU
- Various other small improvements and fixes
* tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (92 commits)
watchdog: diag288_wdt: Remove KMSG_COMPONENT macro
s390/entry: Use lay instead of aghik
s390/vdso: Get rid of -m64 flag handling
s390/vdso: Rename vdso64 to vdso
s390: Rename head64.S to head.S
s390/vdso: Use common STABS_DEBUG and DWARF_DEBUG macros
s390: Add stackprotector support
s390/modules: Simplify module_finalize() slightly
s390: Remove KMSG_COMPONENT macro
s390/percpu: Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
s390/ap: Restrict driver_override versus apmask and aqmask use
s390/ap: Rename mutex ap_perms_mutex to ap_attr_mutex
s390/ap: Support driver_override for AP queue devices
s390/ap: Use all-bits-one apmask/aqmask for vfio in_use() checks
s390/debug: Update description of resize operation
s390/syscalls: Switch to generic system call table generation
s390/syscalls: Remove system call table pointer from thread_struct
s390/uapi: Remove 31 bit support from uapi header files
s390: Remove compat support
tools: Remove s390 compat support
...
Remove s390 compat support from everything within tools, since s390 compat
support will be removed from the kernel.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Weißschuh <linux@weissschuh.net> # tools/nolibc selftests/nolibc
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net> # selftests/vDSO
Acked-by: Alexei Starovoitov <ast@kernel.org> # bpf bits
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Handle recursive typedefs in BTF deduplication
Pahole fails to encode BTF for some Go projects (e.g. Kubernetes and
Podman) due to recursive type definitions that create reference loops
not representable in C. These recursive typedefs trigger a failure in
the BTF deduplication algorithm.
This patch extends btf_dedup_ref_type() to properly handle potential
recursion for BTF_KIND_TYPEDEF, similar to how recursion is already
handled for BTF_KIND_STRUCT. This allows pahole to successfully
generate BTF for Go binaries using recursive types without impacting
existing C-based workflows.
Suggested-by: Tristan d'Audibert <tristan.daudibert@gmail.com>
Co-developed-by: Martin Horth <martin.horth@telecom-sudparis.eu>
Co-developed-by: Ouail Derghal <ouail.derghal@imt-atlantique.fr>
Co-developed-by: Guilhem Jazeron <guilhem.jazeron@inria.fr>
Co-developed-by: Ludovic Paillat <ludovic.paillat@inria.fr>
Co-developed-by: Robin Theveniaut <robin.theveniaut@irit.fr>
Signed-off-by: Martin Horth <martin.horth@telecom-sudparis.eu>
Signed-off-by: Ouail Derghal <ouail.derghal@imt-atlantique.fr>
Signed-off-by: Guilhem Jazeron <guilhem.jazeron@inria.fr>
Signed-off-by: Ludovic Paillat <ludovic.paillat@inria.fr>
Signed-off-by: Robin Theveniaut <robin.theveniaut@irit.fr>
Signed-off-by: Paul Houssel <paul.houssel@orange.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/bf00857b1e06f282aac12f6834de7396a7547ba6.1763037045.git.paul.houssel@orange.com
For v4 instruction set LLVM is allowed to generate indirect jumps for
switch statements and for 'goto *rX' assembly. Every such a jump will
be accompanied by necessary metadata, e.g. (`llvm-objdump -Sr ...`):
0: r2 = 0x0 ll
0000000000000030: R_BPF_64_64 BPF.JT.0.0
Here BPF.JT.1.0 is a symbol residing in the .jumptables section:
Symbol table:
4: 0000000000000000 240 OBJECT GLOBAL DEFAULT 4 BPF.JT.0.0
The -bpf-min-jump-table-entries llvm option may be used to control the
minimal size of a switch which will be converted to an indirect jumps.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20251105090410.1250500-11-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Rename bpf_stream_vprintk() to bpf_stream_vprintk_impl().
This makes bpf_stream_vprintk() follow the already established "_impl"
suffix-based naming convention for kfuncs with the bpf_prog_aux
argument provided by the verifier implicitly. This convention will be
taken advantage of with the upcoming KF_IMPLICIT_ARGS feature to
preserve backwards compatibility to BPF programs.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Link: https://lore.kernel.org/r/20251104-implv2-v3-2-4772b9ae0e06@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ihor Solodrai <ihor.solodrai@linux.dev>
When creating multi-split BTF we correctly set the start string offset
to be the size of the base string section plus the base BTF start
string offset; the latter is needed for multi-split BTF since the
offset is non-zero there.
Unfortunately the BTF parsing case needed that logic and it was
missed.
Fixes: 4e29128a9a ("libbpf/btf: Fix string handling to support multi-split BTF")
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20251104203309.318429-2-alan.maguire@oracle.com
Commit be2f2d1680 ("libbpf: Deprecate bpf_program__load() API") marked
bpf_program__load() as deprecated starting with libbpf v0.6. And later
in commit 146bf811f5 ("libbpf: remove most other deprecated high-level
APIs") actually removed the bpf_program__load() implementation and
related old high-level APIs.
This patch update the comment in bpf_program__set_attach_target() to
remove the reference to the deprecated interface bpf_program__load().
Signed-off-by: Jianyun Gao <jianyungao89@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20251103120727.145965-1-jianyungao89@gmail.com
The variable "memlock_rlim_max" referenced in the comment does not exist.
I think that the author probably meant the variable "memlock_rlim". So,
correct it.
Signed-off-by: Jianyun Gao <jianyungao89@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20251027032008.738944-1-jianyungao89@gmail.com
In the elf_sec_data() function, the input parameter 'scn' will be
evaluated. If it is NULL, then it will directly return NULL. Therefore,
the return value of the elf_sec_data() function already takes into
account the case where the input parameter scn is NULL. Therefore,
subsequently, the code only needs to check whether the return value of
the elf_sec_data() function is NULL.
Signed-off-by: Jianyun Gao <jianyungao89@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20251024080802.642189-1-jianyungao89@gmail.com
retsnoop's build on powerpc (ppc64le) architecture ([0]) failed due to
wrong definition of PT_REGS_SP() macro. Looking at powerpc's
implementation of stack unwinding in perf_callchain_user_64() clearly
shows that stack pointer register is gpr[1].
Fix libbpf's definition of __PT_SP_REG for powerpc to fix all this.
[0] https://kojipkgs.fedoraproject.org/work/tasks/1544/137921544/build.log
Fixes: 138d6153a1 ("samples/bpf: Enable powerpc support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Naveen N Rao (AMD) <naveen@kernel.org>
Link: https://lore.kernel.org/r/20251020203643.989467-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The commit 6c918709bd ("libbpf: Refactor bpf_object__reloc_code")
added the bpf_object__append_subprog_code() with incorrect indentations.
Use tabs instead. (This also makes a consequent commit better readable.)
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20251019202145.3944697-14-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
These violate aliasing rules and may be miscompiled unless
-fno-strict-aliasing is used. Replace them with the standard memcpy()
solution. Note that compilers know how to optimize this properly.
Fixes: 4a1c9e544b ("libbpf: remove linux/unaligned.h dependency for libbpf_sha256()")
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20251006012037.159295-1-ebiggers@kernel.org
The recent sha256 patch uses a GCC pragma to suppress compile errors for
a packed struct, but omits a needed pragma (see related link) and thus
still raises errors: (e.g. on GCC 12.3 armhf)
libbpf_utils.c:153:29: error: packed attribute causes inefficient alignment for ‘__val’ [-Werror=attributes]
153 | struct __packed_u32 { __u32 __val; } __attribute__((packed));
| ^~~~~
Resolve by adding the GCC diagnostic pragma to ignore "-Wattributes".
Link: https://lore.kernel.org/bpf/CAP-5=fXURWoZu2j6Y8xQy23i7=DfgThq3WC1RkGFBx-4moQKYQ@mail.gmail.com/
Fixes: 4a1c9e544b ("libbpf: remove linux/unaligned.h dependency for libbpf_sha256()")
Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
linux/unaligned.h include dependency is causing issues for libbpf's
Github mirror due to {get,put}_unaligned_be32() usage.
So get rid of it by implementing custom variants of those macros that
will work both in kernel and Github mirror repos.
Also switch round_up() to roundup(), as the former is not available in
Github mirror (and is just a subtly more specific variant of roundup()
anyways).
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20251001171326.3883055-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Move sha256 implementation out of already large and unwieldy libbpf.c
into libbpf_utils.c where we'll keep reusable helpers.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20251001171326.3883055-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Get rid of str_err.{c,h} by moving implementation of libbpf_errstr()
into libbpf_utils.c and declarations into libbpf_internal.h.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20251001171326.3883055-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
libbpf_strerror_r() is not exposed as public API and neither is it used
inside libbpf itself. Remove it altogether.
Same for STRERR_BUFSIZE, it's just an orphaned leftover constant which
we missed to clean up some time earlier.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20251001171326.3883055-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Libbpf is missing one convenient place to put common "utils"-like code
that is generic and usable from multiple places. Use libbpf_errno.c as
the base for more generic libbpf_utils.c.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20251001171326.3883055-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Reimplement libbpf_sha256() using some basic SHA-256 C code. This
eliminates the newly-added dependency on AF_ALG, which is a problematic
UAPI that is not supported by all kernels.
Make libbpf_sha256() return void, since it can no longer fail. This
simplifies some callers. Also drop the unnecessary 'sha_out_sz'
parameter. Finally, also fix the typo in "compute_sha_udpate_offsets".
Fixes: c297fe3e9f ("libbpf: Implement SHA256 internal helper")
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/r/20250928003833.138407-1-ebiggers@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When a module registers a struct_ops, the struct_ops type and its
corresponding map_value type ("bpf_struct_ops_") may reside in different
btf objects, here are four possible case:
+--------+---------------+-------------+---------------------------------+
| |bpf_struct_ops_| xxx_ops | |
+--------+---------------+-------------+---------------------------------+
| case 0 | btf_vmlinux | btf_vmlinux | be used and reg only in vmlinux |
+--------+---------------+-------------+---------------------------------+
| case 1 | btf_vmlinux | mod_btf | INVALID |
+--------+---------------+-------------+---------------------------------+
| case 2 | mod_btf | btf_vmlinux | reg in mod but be used both in |
| | | | vmlinux and mod. |
+--------+---------------+-------------+---------------------------------+
| case 3 | mod_btf | mod_btf | be used and reg only in mod |
+--------+---------------+-------------+---------------------------------+
Currently we figure out the mod_btf by searching with the struct_ops type,
which makes it impossible to figure out the mod_btf when the struct_ops
type is in btf_vmlinux while it's corresponding map_value type is in
mod_btf (case 2).
The fix is to use the corresponding map_value type ("bpf_struct_ops_")
as the lookup anchor instead of the struct_ops type to figure out the
`btf` and `mod_btf` via find_ksym_btf_id(), and then we can locate
the kern_type_id via btf__find_by_name_kind() with the `btf` we just
obtained from find_ksym_btf_id().
With this change the lookup obtains the correct btf and mod_btf for case 2,
preserves correct behavior for other valid cases, and still fails as
expected for the invalid scenario (case 1).
Fixes: 590a008882 ("bpf: libbpf: Add STRUCT_OPS support")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/bpf/20250926071751.108293-1-alibuda@linux.alibaba.com
To fulfill the BPF signing contract, represented as Sig(I_loader ||
H_meta), the generated trusted loader program must verify the integrity
of the metadata. This signature cryptographically binds the loader's
instructions (I_loader) to a hash of the metadata (H_meta).
The verification process is embedded directly into the loader program.
Upon execution, the loader loads the runtime hash from struct bpf_map
i.e. BPF_PSEUDO_MAP_IDX and compares this runtime hash against an
expected hash value that has been hardcoded directly by
bpf_obj__gen_loader.
The load from bpf_map can be improved by calling
BPF_OBJ_GET_INFO_BY_FD from the kernel context after BPF_OBJ_GET_INFO_BY_FD
has been updated for being called from the kernel context.
The following instructions are generated:
ld_imm64 r1, const_ptr_to_map // insn[0].src_reg == BPF_PSEUDO_MAP_IDX
r2 = *(u64 *)(r1 + 0);
ld_imm64 r3, sha256_of_map_part1 // constant precomputed by
bpftool (part of H_meta)
if r2 != r3 goto out;
r2 = *(u64 *)(r1 + 8);
ld_imm64 r3, sha256_of_map_part2 // (part of H_meta)
if r2 != r3 goto out;
r2 = *(u64 *)(r1 + 16);
ld_imm64 r3, sha256_of_map_part3 // (part of H_meta)
if r2 != r3 goto out;
r2 = *(u64 *)(r1 + 24);
ld_imm64 r3, sha256_of_map_part4 // (part of H_meta)
if r2 != r3 goto out;
...
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250921160120.9711-4-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* The metadata map is created with as an exclusive map (with an
excl_prog_hash) This restricts map access exclusively to the signed
loader program, preventing tampering by other processes.
* The map is then frozen, making it read-only from userspace.
* BPF_OBJ_GET_INFO_BY_ID instructs the kernel to compute the hash of the
metadata map (H') and store it in bpf_map->sha.
* The loader is then loaded with the signature which is then verified by
the kernel.
loading signed programs prebuilt into the kernel are not currently
supported. These can supported by enabling BPF_OBJ_GET_INFO_BY_ID to be
called from the kernel.
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250921160120.9711-3-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch extends the BPF_PROG_LOAD command by adding three new fields
to `union bpf_attr` in the user-space API:
- signature: A pointer to the signature blob.
- signature_size: The size of the signature blob.
- keyring_id: The serial number of a loaded kernel keyring (e.g.,
the user or session keyring) containing the trusted public keys.
When a BPF program is loaded with a signature, the kernel:
1. Retrieves the trusted keyring using the provided `keyring_id`.
2. Verifies the supplied signature against the BPF program's
instruction buffer.
3. If the signature is valid and was generated by a key in the trusted
keyring, the program load proceeds.
4. If no signature is provided, the load proceeds as before, allowing
for backward compatibility. LSMs can chose to restrict unsigned
programs and implement a security policy.
5. If signature verification fails for any reason,
the program is not loaded.
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250921160120.9711-2-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Implement setters and getters that allow map to be registered as
exclusive to the specified program. The registration should be done
before the exclusive program is loaded.
Signed-off-by: KP Singh <kpsingh@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-5-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Use AF_ALG sockets to not have libbpf depend on OpenSSL. The helper is
used for the loader generation code to embed the metadata hash in the
loader program and also by the bpf_map__make_exclusive API to calculate
the hash of the program the map is exclusive to.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-4-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Remove unused 'elf' and 'path' parameters from parse_usdt_note function
signature. These parameters are not referenced within the function body
and only add unnecessary complexity.
The function only requires the note header, data buffer, offsets, and
output structure to perform USDT note parsing.
Update function declaration, definition, and the single call site in
collect_usdt_targets() to match the simplified signature.
This is a safe internal cleanup as parse_usdt_note is a static function.
Signed-off-by: Jiawei Zhao <phoenix500526@163.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20250904030525.1932293-1-phoenix500526@163.com
On x86-64, USDT arguments can be specified using Scale-Index-Base (SIB)
addressing, e.g. "1@-96(%rbp,%rax,8)". The current USDT implementation
in libbpf cannot parse this format, causing `bpf_program__attach_usdt()`
to fail with -ENOENT (unrecognized register).
This patch fixes this by implementing the necessary changes:
- add correct handling for SIB-addressed arguments in `bpf_usdt_arg`.
- add adaptive support to `__bpf_usdt_arg_type` and
`__bpf_usdt_arg_spec` to represent SIB addressing parameters.
Signed-off-by: Jiawei Zhao <phoenix500526@163.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250827053128.1301287-2-phoenix500526@163.com
Add missing LIBBPF_API macro for bpf_object__prepare function to enable
its export. libbpf.map had bpf_object__prepare already listed.
Fixes: 1315c28ed8 ("libbpf: Split bpf object load into prepare/load")
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20250819215119.37795-1-mykyta.yatsenko5@gmail.com
Previously, re-using pinned DEVMAP maps would always fail, because
get_map_info on a DEVMAP always returns flags with BPF_F_RDONLY_PROG set,
but BPF_F_RDONLY_PROG being set on a map during creation is invalid.
Thus, ignore the BPF_F_RDONLY_PROG flag in the flags returned from
get_map_info when checking for compatibility with an existing DEVMAP.
The same problem is handled in a third-party ebpf library:
- https://github.com/cilium/ebpf/issues/925
- https://github.com/cilium/ebpf/pull/930
Fixes: 0cdbb4b09a ("devmap: Allow map lookups from eBPF")
Signed-off-by: Yureka Lilian <yuka@yuka.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250814180113.1245565-3-yuka@yuka.dev
Automatically enabling a perf event after attaching a BPF prog to it is
not always desirable.
Add a new "dont_enable" field to struct bpf_perf_event_opts. While
introducing "enable" instead would be nicer in that it would avoid
a double negation in the implementation, it would make
DECLARE_LIBBPF_OPTS() less efficient.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Co-developed-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20250806162417.19666-2-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Though mod_len is only read when mod_name != NULL and both are initialized
together, gcc15 produces a warning with -Werror=maybe-uninitialized:
libbpf.c: In function 'find_kernel_btf_id.constprop':
libbpf.c:10100:33: error: 'mod_len' may be used uninitialized [-Werror=maybe-uninitialized]
10100 | if (mod_name && strncmp(mod->name, mod_name, mod_len) != 0)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libbpf.c:10070:21: note: 'mod_len' was declared here
10070 | int ret, i, mod_len;
| ^~~~~~~
Silence the false positive.
Signed-off-by: Achill Gilgenast <fossdd@pwned.life>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250729094611.2065713-1-fossdd@pwned.life
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Fuzzer reported a memory access error in bpf_program__record_reloc()
that happens when:
- ".addr_space.1" section exists
- there is a relocation referencing this section
- there are no arena maps defined in BTF.
Sanity checks for maps existence are already present in
bpf_program__record_reloc(), hence this commit adds another one.
[1] https://github.com/libbpf/libbpf/actions/runs/16375110681/job/46272998064
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250718222059.281526-1-eddyz87@gmail.com
When compiling libbpf with some compilers, this warning is triggered:
libbpf.c: In function ‘bpf_object__gen_loader’:
libbpf.c:9209:28: error: ‘calloc’ sizes specified with ‘sizeof’ in the earlier argument and not in the later argument [-Werror=calloc-transposed-args]
9209 | gen = calloc(sizeof(*gen), 1);
| ^
libbpf.c:9209:28: note: earlier argument should specify number of elements, later size of each element
Fix this by inverting the calloc() arguments.
Signed-off-by: Matteo Croce <teknoraver@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20250717200337.49168-1-technoboy85@gmail.com
Initial __arena global variable support implementation in libbpf
contains a bug: it remembers struct bpf_map pointer for arena, which is
used later on to process relocations. Recording this pointer is
problematic because map pointers are not stable during ELF relocation
collection phase, as an array of struct bpf_map's can be reallocated,
invalidating all the pointers. Libbpf is dealing with similar issues by
using a stable internal map index, though for BPF arena map specifically
this approach wasn't used due to an oversight.
The resulting behavior is non-deterministic issue which depends on exact
layout of ELF object file, number of actual maps, etc. We didn't hit
this until very recently, when this bug started triggering crash in BPF
CI when validating one of sched-ext BPF programs.
The fix is rather straightforward: we just follow an established pattern
of remembering map index (just like obj->kconfig_map_idx, for example)
instead of `struct bpf_map *`, and resolving index to a pointer at the
point where map information is necessary.
While at it also add debug-level message for arena-related relocation
resolution information, which we already have for all other kinds of
maps.
Fixes: 2e7ba4f8fd ("libbpf: Recognize __arena global variables.")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250718001009.610955-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Introduce a libbpf API so that users can read data from a given BPF
stream for a BPF prog fd. For now, only the low-level syscall wrapper
is provided, we can add a bpf_program__* accessor as a follow up if
needed.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-11-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a convenience macro to print data to the BPF streams. BPF_STDOUT and
BPF_STDERR stream IDs in the vmlinux.h can be passed to the macro to
print to the respective streams.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-10-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cross-merge BPF, perf and other fixes after downstream PRs.
It restores BPF CI to green after critical fix
commit bc4394e5e7 ("perf: Fix the throttle error of some clock events")
No conflicts.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The `name` field in `obj->externs` points into the BTF data at initial
open time. However, some functions may invalidate this after opening and
before loading (e.g. `bpf_map__set_value_size`), which results in
pointers into freed memory and undefined behavior.
The simplest solution is to simply `strdup` these strings, similar to
the `essent_name`, and free them at the same time.
In order to test this path, the `global_map_resize` BPF selftest is
modified slightly to ensure the presence of an extern, which causes this
test to fail prior to the fix. Given there isn't an obvious API or error
to test against, I opted to add this to the existing test as an aspect
of the resizing feature rather than duplicate the test.
Fixes: 9d0a23313b ("libbpf: Add capability for resizing datasec maps")
Signed-off-by: Adin Scannell <amscanne@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250625050215.2777374-1-amscanne@meta.com
When btf_dump__new() fails to allocate memory for the internal hashmap
(btf_dump->type_names), it returns an error code. However, the cleanup
function btf_dump__free() does not check if btf_dump->type_names is NULL
before attempting to free it. This leads to a null pointer dereference
when btf_dump__free() is called on a btf_dump object.
Fixes: 351131b51c ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Yuan Chen <chenyuan@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250618011933.11423-1-chenyuan_fl@163.com
Currently libbpf supports bpf_program__attach_cgroup() with signature:
LIBBPF_API struct bpf_link *
bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
To support mprog style attachment, additionsl fields like flags,
relative_{fd,id} and expected_revision are needed.
Add a new API:
LIBBPF_API struct bpf_link *
bpf_program__attach_cgroup_opts(const struct bpf_program *prog, int cgroup_fd,
const struct bpf_cgroup_opts *opts);
where bpf_cgroup_opts contains all above needed fields.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250606163146.2429212-1-yonghong.song@linux.dev
libbpf_err_ptr() helpers are meant to return NULL and set errno, if
there is an error. But btf_parse_raw_mmap() is meant to be used
internally and is expected to return ERR_PTR() values. Because of this
mismatch, when libbpf tries to mmap /sys/kernel/btf/vmlinux, we don't
detect the error correctly with IS_ERR() check, and never fallback to
old non-mmap-based way of loading vmlinux BTF.
Fix this by using proper ERR_PTR() returns internally.
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes: 3c0421c93c ("libbpf: Use mmap to parse vmlinux BTF from sysfs")
Cc: Lorenz Bauer <lmb@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20250606202134.2738910-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The BTF dumper code currently displays arrays of characters as just that -
arrays, with each character formatted individually. Sometimes this is what
makes sense, but it's nice to be able to treat that array as a string.
This change adds a special case to the btf_dump functionality to allow
0-terminated arrays of single-byte integer values to be printed as
character strings. Characters for which isprint() returns false are
printed as hex-escaped values. This is enabled when the new ".emit_strings"
is set to 1 in the btf_dump_type_data_opts structure.
As an example, here's what it looks like to dump the string "hello" using
a few different field values for btf_dump_type_data_opts (.compact = 1):
- .emit_strings = 0, .skip_names = 0: (char[6])['h','e','l','l','o',]
- .emit_strings = 0, .skip_names = 1: ['h','e','l','l','o',]
- .emit_strings = 1, .skip_names = 0: (char[6])"hello"
- .emit_strings = 1, .skip_names = 1: "hello"
Here's the string "h\xff", dumped with .compact = 1 and .skip_names = 1:
- .emit_strings = 0: ['h',-1,]
- .emit_strings = 1: "h\xff"
Signed-off-by: Blake Jones <blakejones@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250603203701.520541-1-blakejones@google.com
-----BEGIN PGP SIGNATURE-----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=j3t8
-----END PGP SIGNATURE-----
Merge tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Fix and improve BTF deduplication of identical BTF types (Alan
Maguire and Andrii Nakryiko)
- Support up to 12 arguments in BPF trampoline on arm64 (Xu Kuohai and
Alexis Lothoré)
- Support load-acquire and store-release instructions in BPF JIT on
riscv64 (Andrea Parri)
- Fix uninitialized values in BPF_{CORE,PROBE}_READ macros (Anton
Protopopov)
- Streamline allowed helpers across program types (Feng Yang)
- Support atomic update for hashtab of BPF maps (Hou Tao)
- Implement json output for BPF helpers (Ihor Solodrai)
- Several s390 JIT fixes (Ilya Leoshkevich)
- Various sockmap fixes (Jiayuan Chen)
- Support mmap of vmlinux BTF data (Lorenz Bauer)
- Support BPF rbtree traversal and list peeking (Martin KaFai Lau)
- Tests for sockmap/sockhash redirection (Michal Luczaj)
- Introduce kfuncs for memory reads into dynptrs (Mykyta Yatsenko)
- Add support for dma-buf iterators in BPF (T.J. Mercier)
- The verifier support for __bpf_trap() (Yonghong Song)
* tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (135 commits)
bpf, arm64: Remove unused-but-set function and variable.
selftests/bpf: Add tests with stack ptr register in conditional jmp
bpf: Do not include stack ptr register in precision backtracking bookkeeping
selftests/bpf: enable many-args tests for arm64
bpf, arm64: Support up to 12 function arguments
bpf: Check rcu_read_lock_trace_held() in bpf_map_lookup_percpu_elem()
bpf: Avoid __bpf_prog_ret0_warn when jit fails
bpftool: Add support for custom BTF path in prog load/loadall
selftests/bpf: Add unit tests with __bpf_trap() kfunc
bpf: Warn with __bpf_trap() kfunc maybe due to uninitialized variable
bpf: Remove special_kfunc_set from verifier
selftests/bpf: Add test for open coded dmabuf_iter
selftests/bpf: Add test for dmabuf_iter
bpf: Add open coded dmabuf iterator
bpf: Add dmabuf iterator
dma-buf: Rename debugfs symbols
bpf: Fix error return value in bpf_copy_from_user_dynptr
libbpf: Use mmap to parse vmlinux BTF from sysfs
selftests: bpf: Add a test for mmapable vmlinux BTF
btf: Allow mmap of vmlinux btf
...
Teach libbpf to use mmap when parsing vmlinux BTF from /sys. We don't
apply this to fall-back paths on the regular file system because there
is no way to ensure that modifications underlying the MAP_PRIVATE
mapping are not visible to the process.
Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250520-vmlinux-mmap-v5-3-e8c941acc414@isovalent.com
libbpf handling of split BTF has been written largely with the
assumption that multiple splits are possible, i.e. split BTF on top of
split BTF on top of base BTF. One area where this does not quite work
is string handling in split BTF; the start string offset should be the
base BTF string section length + the base BTF string offset. This
worked in the past because for a single split BTF with base the start
string offset was always 0.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250519165935.261614-2-alan.maguire@oracle.com
Avoid dereferencing bpf_map_skeleton's link field if it's NULL.
If BPF map skeleton is created with the size, that indicates containing
link field, but the field was not actually initialized with valid
bpf_link pointer, libbpf crashes. This may happen when using libbpf-rs
skeleton.
Skeleton loading may still progress, but user needs to attach struct_ops
map separately.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250514113220.219095-1-mykyta.yatsenko5@gmail.com
Return value of the validate_nla() function can be propagated all the
way up to users of libbpf API. In case of error this libbpf version
of validate_nla returns -1 which will be seen as -EPERM from user's
point of view. Instead, return a more reasonable -EINVAL.
Fixes: bbf48c18ee ("libbpf: add error reporting in XDP")
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250510182011.2246631-1-a.s.protopopov@gmail.com
BTF dedup has a strong assumption that compiler with deduplicate identical
types within any given compilation unit (i.e., .c file). This property
is used when establishing equilvalence of two subgraphs of types.
Unfortunately, this property doesn't always holds in practice. We've
seen cases of having truly identical structs, unions, array definitions,
and, most recently, even pointers to the same type being duplicated
within CU.
Previously, we mitigated this on a case-by-case basis, adding a few
simple heuristics for validating that two BTF types (having two
different type IDs) are structurally the same. But this approach scales
poorly, and we can have more weird cases come up in the future.
So let's take a half-step back, and implement a bit more generic
structural equivalence check, recursively. We still limit it to
reasonable depth to avoid long reference loops. Depth-wise limiting of
potentially cyclical graph isn't great, but as I mentioned below doesn't
seem to be detrimental performance-wise. We can always improve this in
the future with per-type visited markers, if necessary.
Performance-wise this doesn't seem too affect vmlinux BTF dedup, which
makes sense because this logic kicks in not so frequently and only if we
already established a canonical candidate type match, but suddenly find
a different (but probably identical) type.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/r/20250501235231.1339822-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
With the latest LLVM bpf selftests build will fail with
the following error message:
progs/profiler.inc.h:710:31: error: default initialization of an object of type 'typeof ((parent_task)->real_cred->uid.val)' (aka 'const unsigned int') leaves the object uninitialized and is incompatible with C++ [-Werror,-Wdefault-const-init-unsafe]
710 | proc_exec_data->parent_uid = BPF_CORE_READ(parent_task, real_cred, uid.val);
| ^
tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:520:35: note: expanded from macro 'BPF_CORE_READ'
520 | ___type((src), a, ##__VA_ARGS__) __r; \
| ^
This happens because BPF_CORE_READ (and other macro) declare the
variable __r using the ___type macro which can inherit const modifier
from intermediate types.
Fix this by using __typeof_unqual__, when supported. (And when it
is not supported, the problem shouldn't appear, as older compilers
haven't complained.)
Fixes: 792001f4f7 ("libbpf: Add user-space variants of BPF_CORE_READ() family of macros")
Fixes: a4b09a9ef9 ("libbpf: Add non-CO-RE variants of BPF_CORE_READ() macro family")
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250502193031.3522715-1-a.s.protopopov@gmail.com
Return values of the linker_append_sec_data() and the
linker_append_elf_relos() functions are propagated all the
way up to users of libbpf API. In some error cases these
functions return -1 which will be seen as -EPERM from user's
point of view. Instead, return a more reasonable -EINVAL.
Fixes: faf6ed321c ("libbpf: Add BPF static linker APIs")
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250430120820.2262053-1-a.s.protopopov@gmail.com
Recently as a side-effect of
commit ac053946f5 ("compiler.h: introduce TYPEOF_UNQUAL() macro")
issues were observed in deduplication between modules and kernel BTF
such that a large number of kernel types were not deduplicated so
were found in module BTF (task_struct, bpf_prog etc). The root cause
appeared to be a failure to dedup struct types, specifically those
with members that were pointers with __percpu annotations.
The issue in dedup is at the point that we are deduplicating structures,
we have not yet deduplicated reference types like pointers. If multiple
copies of a pointer point at the same (deduplicated) integer as in this
case, we do not see them as identical. Special handling already exists
to deal with structures and arrays, so add pointer handling here too.
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250429161042.2069678-1-alan.maguire@oracle.com
This patch fixes a thread safety bug where libbpf_print uses the
global variable storing the print function pointer rather than the local
variable that had the print function set via __atomic_load_n.
Fixes: f1cb927cdb ("libbpf: Ensure print callback usage is thread-safe")
Signed-off-by: Jonathan Wiepert <jonathan.wiepert@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Mykyta Yatsenko <mykyta.yatsenko5@gmail.com>
Link: https://lore.kernel.org/bpf/20250424221457.793068-1-jonathan.wiepert@gmail.com
It seems that sample_period is not used in perf buffer. Actually, only
wakeup_events are meaningful to enable events aggregation for wakeup notification.
Remove sample_period setting code to avoid confusion.
Fixes: fb84b82246 ("libbpf: add perf buffer API")
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/bpf/20250423163901.2983689-1-chen.dylane@linux.dev