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2025-09-28libbpf: Replace AF_ALG with open coded SHA-256Eric Biggers
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: c297fe3e9f99 ("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>
2025-09-26libbpf: Fix error when st-prefix_ops and ops from differ btfD. Wythe
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: 590a00888250 ("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
2025-09-22libbpf: Embed and verify the metadata hash in the loaderKP Singh
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>
2025-09-22libbpf: Update light skeleton for signingKP Singh
* 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>
2025-09-22bpf: Implement signature verification for BPF programsKP Singh
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>
2025-09-18libbpf: Support exclusive map creationKP Singh
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>
2025-09-18libbpf: Implement SHA256 internal helperKP Singh
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>
2025-09-04libbpf: Remove unused args in parse_usdt_noteJiawei Zhao
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
2025-08-27libbpf: Fix USDT SIB argument handling causing unrecognized register errorJiawei Zhao
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
2025-08-20libbpf: Add documentation to version and error API functionsCryolitia PukNgae
Add documentation for the following API functions: - libbpf_major_version() - libbpf_minor_version() - libbpf_version_string() - libbpf_strerror() Signed-off-by: Cryolitia PukNgae <cryolitia@uniontech.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250820-libbpf-doc-1-v1-1-13841f25a134@uniontech.com
2025-08-20libbpf: Export bpf_object__prepare symbolMykyta Yatsenko
Add missing LIBBPF_API macro for bpf_object__prepare function to enable its export. libbpf.map had bpf_object__prepare already listed. Fixes: 1315c28ed809 ("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
2025-08-15libbpf: Fix reuse of DEVMAPYureka Lilian
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: 0cdbb4b09a06 ("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
2025-08-07libbpf: Add the ability to suppress perf event enablementIlya Leoshkevich
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>
2025-07-31libbpf: Avoid possible use of uninitialized mod_lenAchill Gilgenast
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>
2025-07-18libbpf: Verify that arena map exists when adding arena relocationsEduard Zingerman
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
2025-07-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc6Alexei Starovoitov
Cross-merge BPF and other fixes after downstream PR. No conflicts. Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-18libbpf: Fix warning in calloc() usageMatteo Croce
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
2025-07-17libbpf: Fix handling of BPF arena relocationsAndrii Nakryiko
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: 2e7ba4f8fd1f ("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>
2025-07-16libbpf: start v1.7 dev cycleAndrii Nakryiko
With libbpf 1.6.0 released, adjust libbpf.map and libbpf_version.h to start v1.7 development cycles. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20250716175936.2343013-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-07libbpf: __arg_untrusted in bpf_helpers.hEduard Zingerman
Make btf_decl_tag("arg:untrusted") available for libbpf users via macro. Makes the following usage possible: void foo(struct bar *p __arg_untrusted) { ... } void bar(struct foo *p __arg_trusted) { ... foo(p->buz->bar); // buz derefrence looses __trusted ... } Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250704230354.1323244-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03libbpf: Introduce bpf_prog_stream_read() APIKumar Kartikeya Dwivedi
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>
2025-07-03libbpf: Add bpf_stream_printk() macroKumar Kartikeya Dwivedi
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>
2025-06-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc3Alexei Starovoitov
Cross-merge BPF, perf and other fixes after downstream PRs. It restores BPF CI to green after critical fix commit bc4394e5e79c ("perf: Fix the throttle error of some clock events") No conflicts. Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-25libbpf: Fix possible use-after-free for externsAdin Scannell
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: 9d0a23313b1a ("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
2025-06-23libbpf: Fix null pointer dereference in btf_dump__free on allocation failureYuan Chen
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: 351131b51c7a ("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
2025-06-09libbpf: Support link-based cgroup attach with optionsYonghong Song
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
2025-06-06libbpf: Handle unsupported mmap-based /sys/kernel/btf/vmlinux correctlyAndrii Nakryiko
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: 3c0421c93ce4 ("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>
2025-06-05libbpf: Add support for printing BTF character arrays as stringsBlake Jones
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
2025-06-05libbpf: Correct some typos and syntax issues in usdt docJiawei Zhao
Fix some incorrect words, such as "and" -> "an", "it's" -> "its". Fix some grammar issues, such as removing redundant "will", "would complicated" -> "would complicate". Signed-off-by: Jiawei Zhao <Phoenix500526@163.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250531095111.57824-1-Phoenix500526@163.com
2025-05-28Merge tag 'bpf-next-6.16' of ↵Linus Torvalds
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 ...
2025-05-23libbpf: Use mmap to parse vmlinux BTF from sysfsLorenz Bauer
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
2025-05-20libbpf/btf: Fix string handling to support multi-split BTFAlan Maguire
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
2025-05-14libbpf: Check bpf_map_skeleton link for NULLMykyta Yatsenko
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
2025-05-12libbpf: Use proper errno value in nlattrAnton Protopopov
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: bbf48c18ee0c ("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
2025-05-05libbpf: Improve BTF dedup handling of "identical" BTF typesAndrii Nakryiko
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>
2025-05-05bpf: Fix uninitialized values in BPF_{CORE,PROBE}_READAnton Protopopov
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: 792001f4f7aa ("libbpf: Add user-space variants of BPF_CORE_READ() family of macros") Fixes: a4b09a9ef945 ("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
2025-04-30libbpf: Use proper errno value in linkerAnton Protopopov
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: faf6ed321cf6 ("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
2025-04-29libbpf: Add identical pointer detection to btf_dedup_is_equiv()Alan Maguire
Recently as a side-effect of commit ac053946f5c4 ("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
2025-04-25Use thread-safe function pointer in libbpf_printJonathan Wiepert
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: f1cb927cdb62 ("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
2025-04-25libbpf: Remove sample_period init in perf_bufferTao Chen
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: fb84b8224655 ("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
2025-04-22libbpf: Fix event name too long errorFeng Yang
When the binary path is excessively long, the generated probe_name in libbpf exceeds the kernel's MAX_EVENT_NAME_LEN limit (64 bytes). This causes legacy uprobe event attachment to fail with error code -22. The fix reorders the fields to place the unique ID before the name. This ensures that even if truncation occurs via snprintf, the unique ID remains intact, preserving event name uniqueness. Additionally, explicit checks with MAX_EVENT_NAME_LEN are added to enforce length constraints. Before Fix: ./test_progs -t attach_probe/kprobe-long_name ...... libbpf: failed to add legacy kprobe event for 'bpf_testmod_looooooooooooooooooooooooooooooong_name+0x0': -EINVAL libbpf: prog 'handle_kprobe': failed to create kprobe 'bpf_testmod_looooooooooooooooooooooooooooooong_name+0x0' perf event: -EINVAL test_attach_kprobe_long_event_name:FAIL:attach_kprobe_long_event_name unexpected error: -22 test_attach_probe:PASS:uprobe_ref_ctr_cleanup 0 nsec #13/11 attach_probe/kprobe-long_name:FAIL #13 attach_probe:FAIL ./test_progs -t attach_probe/uprobe-long_name ...... libbpf: failed to add legacy uprobe event for /root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9: -EINVAL libbpf: prog 'handle_uprobe': failed to create uprobe '/root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9' perf event: -EINVAL test_attach_uprobe_long_event_name:FAIL:attach_uprobe_long_event_name unexpected error: -22 #13/10 attach_probe/uprobe-long_name:FAIL #13 attach_probe:FAIL After Fix: ./test_progs -t attach_probe/uprobe-long_name #13/10 attach_probe/uprobe-long_name:OK #13 attach_probe:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED ./test_progs -t attach_probe/kprobe-long_name #13/11 attach_probe/kprobe-long_name:OK #13 attach_probe:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED Fixes: 46ed5fc33db9 ("libbpf: Refactor and simplify legacy kprobe code") Fixes: cc10623c6810 ("libbpf: Add legacy uprobe attaching support") Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> Signed-off-by: Feng Yang <yangfeng@kylinos.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250417014848.59321-2-yangfeng59949@163.com
2025-04-17libbpf: Support creating and destroying qdiscAmery Hung
Extend struct bpf_tc_hook with handle, qdisc name and a new attach type, BPF_TC_QDISC, to allow users to add or remove any qdisc specified in addition to clsact. Signed-off-by: Amery Hung <amery.hung@bytedance.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20250409214606.2000194-8-ameryhung@gmail.com
2025-04-15libbpf: Verify section type in btf_find_elf_sectionsIhor Solodrai
A valid ELF file may contain a SHT_NOBITS .BTF section. This case is not handled correctly in btf_parse_elf, which leads to a segfault. Before attempting to load BTF section data, check that the section type is SHT_PROGBITS, which is the expected type for BTF data. Fail with an error if the type is different. Bug report: https://github.com/libbpf/libbpf/issues/894 v1: https://lore.kernel.org/bpf/20250408184104.3962949-1-ihor.solodrai@linux.dev/ Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250410182823.1591681-1-ihor.solodrai@linux.dev
2025-04-15libbpf: Fix buffer overflow in bpf_object__init_progViktor Malik
As shown in [1], it is possible to corrupt a BPF ELF file such that arbitrary BPF instructions are loaded by libbpf. This can be done by setting a symbol (BPF program) section offset to a large (unsigned) number such that <section start + symbol offset> overflows and points before the section data in the memory. Consider the situation below where: - prog_start = sec_start + symbol_offset <-- size_t overflow here - prog_end = prog_start + prog_size prog_start sec_start prog_end sec_end | | | | v v v v .....................|################################|............ The report in [1] also provides a corrupted BPF ELF which can be used as a reproducer: $ readelf -S crash Section Headers: [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [ 2] uretprobe.mu[...] PROGBITS 0000000000000000 00000040 0000000000000068 0000000000000000 AX 0 0 8 $ readelf -s crash Symbol table '.symtab' contains 8 entries: Num: Value Size Type Bind Vis Ndx Name ... 6: ffffffffffffffb8 104 FUNC GLOBAL DEFAULT 2 handle_tp Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will point before the actual memory where section 2 is allocated. This is also reported by AddressSanitizer: ================================================================= ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490 READ of size 104 at 0x7c7302fe0000 thread T0 #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76) #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856 #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928 #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930 #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067 #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090 #6 0x000000400c16 in main /poc/poc.c:8 #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4) #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667) #9 0x000000400b34 in _start (/poc/poc+0x400b34) 0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8) allocated by thread T0 here: #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b) #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600) #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018) #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740 The problem here is that currently, libbpf only checks that the program end is within the section bounds. There used to be a check `while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was removed by commit 6245947c1b3c ("libbpf: Allow gaps in BPF program sections to support overriden weak functions"). Add a check for detecting the overflow of `sec_off + prog_sz` to bpf_object__init_prog to fix this issue. [1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md Fixes: 6245947c1b3c ("libbpf: Allow gaps in BPF program sections to support overriden weak functions") Reported-by: lmarch2 <2524158037@qq.com> Signed-off-by: Viktor Malik <vmalik@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com
2025-04-09libbpf: Add getters for BTF.ext func and line infoMykyta Yatsenko
Introducing new libbpf API getters for BTF.ext func and line info, namely: bpf_program__func_info bpf_program__func_info_cnt bpf_program__line_info bpf_program__line_info_cnt This change enables scenarios, when user needs to load bpf_program directly using `bpf_prog_load`, instead of higher-level `bpf_object__load`. Line and func info are required for checking BTF info in verifier; verification may fail without these fields if, for example, program calls `bpf_obj_new`. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250408234417.452565-2-mykyta.yatsenko5@gmail.com
2025-04-04libbpf: Add likely/unlikely macros and use them in selftestsAnton Protopopov
A few selftests and, more importantly, consequent changes to the bpf_helpers.h file, use likely/unlikely macros, so define them here and remove duplicate definitions from existing selftests. Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250331203618.1973691-3-a.s.protopopov@gmail.com
2025-04-04libbpf: Fix implicit memfd_create() for bionicCarlos Llamas
Since memfd_create() is not consistently available across different bionic libc implementations, using memfd_create() directly can break some Android builds: tools/lib/bpf/linker.c:576:7: error: implicit declaration of function 'memfd_create' [-Werror,-Wimplicit-function-declaration] 576 | fd = memfd_create(filename, 0); | ^ To fix this, relocate and inline the sys_memfd_create() helper so that it can be used in "linker.c". Similar issues were previously fixed by commit 9fa5e1a180aa ("libbpf: Call memfd_create() syscall directly"). Fixes: 6d5e5e5d7ce1 ("libbpf: Extend linker API to support in-memory ELF files") Signed-off-by: Carlos Llamas <cmllamas@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250330211325.530677-1-cmllamas@google.com
2025-03-30Merge tag 'bpf-next-6.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Alexei Starovoitov: "For this merge window we're splitting BPF pull request into three for higher visibility: main changes, res_spin_lock, try_alloc_pages. These are the main BPF changes: - Add DFA-based live registers analysis to improve verification of programs with loops (Eduard Zingerman) - Introduce load_acquire and store_release BPF instructions and add x86, arm64 JIT support (Peilin Ye) - Fix loop detection logic in the verifier (Eduard Zingerman) - Drop unnecesary lock in bpf_map_inc_not_zero() (Eric Dumazet) - Add kfunc for populating cpumask bits (Emil Tsalapatis) - Convert various shell based tests to selftests/bpf/test_progs format (Bastien Curutchet) - Allow passing referenced kptrs into struct_ops callbacks (Amery Hung) - Add a flag to LSM bpf hook to facilitate bpf program signing (Blaise Boscaccy) - Track arena arguments in kfuncs (Ihor Solodrai) - Add copy_remote_vm_str() helper for reading strings from remote VM and bpf_copy_from_user_task_str() kfunc (Jordan Rome) - Add support for timed may_goto instruction (Kumar Kartikeya Dwivedi) - Allow bpf_get_netns_cookie() int cgroup_skb programs (Mahe Tardy) - Reduce bpf_cgrp_storage_busy false positives when accessing cgroup local storage (Martin KaFai Lau) - Introduce bpf_dynptr_copy() kfunc (Mykyta Yatsenko) - Allow retrieving BTF data with BTF token (Mykyta Yatsenko) - Add BPF kfuncs to set and get xattrs with 'security.bpf.' prefix (Song Liu) - Reject attaching programs to noreturn functions (Yafang Shao) - Introduce pre-order traversal of cgroup bpf programs (Yonghong Song)" * tag 'bpf-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (186 commits) selftests/bpf: Add selftests for load-acquire/store-release when register number is invalid bpf: Fix out-of-bounds read in check_atomic_load/store() libbpf: Add namespace for errstr making it libbpf_errstr bpf: Add struct_ops context information to struct bpf_prog_aux selftests/bpf: Sanitize pointer prior fclose() selftests/bpf: Migrate test_xdp_vlan.sh into test_progs selftests/bpf: test_xdp_vlan: Rename BPF sections bpf: clarify a misleading verifier error message selftests/bpf: Add selftest for attaching fexit to __noreturn functions bpf: Reject attaching fexit/fmod_ret to __noreturn functions bpf: Only fails the busy counter check in bpf_cgrp_storage_get if it creates storage bpf: Make perf_event_read_output accessible in all program types. bpftool: Using the right format specifiers bpftool: Add -Wformat-signedness flag to detect format errors selftests/bpf: Test freplace from user namespace libbpf: Pass BPF token from find_prog_btf_id to BPF_BTF_GET_FD_BY_ID bpf: Return prog btf_id without capable check bpf: BPF token support for BPF_BTF_GET_FD_BY_ID bpf, x86: Fix objtool warning for timed may_goto bpf: Check map->record at the beginning of check_and_free_fields() ...
2025-03-21libbpf: Add namespace for errstr making it libbpf_errstrIan Rogers
When statically linking symbols can be replaced with those from other statically linked libraries depending on the link order and the hoped for "multiple definition" error may not appear. To avoid conflicts it is good practice to namespace symbols, this change renames errstr to libbpf_errstr. To avoid churn a #define is used to turn use of errstr(err) to libbpf_errstr(err). Fixes: 1633a83bf993 ("libbpf: Introduce errstr() for stringifying errno") Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250320222439.1350187-1-irogers@google.com
2025-03-17libbpf: Pass BPF token from find_prog_btf_id to BPF_BTF_GET_FD_BY_IDMykyta Yatsenko
Pass BPF token from bpf_program__set_attach_target to BPF_BTF_GET_FD_BY_ID bpf command. When freplace program attaches to target program, it needs to look up for BTF of the target, this may require BPF token, if, for example, running from user namespace. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20250317174039.161275-4-mykyta.yatsenko5@gmail.com
generated by cgit (git 2.34.1) at 2025-10-22 07:58:36 +0000