kernel/linux.git/tools/lib/bpf/libbpf_internal.h, branch linux-7.1.y

libbpf: Allow use of feature cache for non-token cases

2026-04-10T19:34:36+00:00

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 Link: https://lore.kernel.org/r/20260408165735.843763-2-alan.maguire@oracle.com Signed-off-by: Alexei Starovoitov

libbpf: Support sanitization of BTF layout for older kernels

2026-03-26T20:53:56+00:00

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20260326145444.2076244-7-alan.maguire@oracle.com

libbpf: Add uprobe syscall feature detection

2026-03-03T16:39:21+00:00

Adding uprobe syscall feature detection that will be used in following changes. Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20260224103915.1369690-2-jolsa@kernel.org Signed-off-by: Alexei Starovoitov

libbpf: Add gating for arena globals relocation feature

2026-02-13T22:14:27+00:00

Add feature gating for the arena globals relocation introduced in commit c1f61171d44b. The commit depends on a previous commit in the same patchset that is absent from older kernels (12a1fe6e12db "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: c1f61171d44b ("libbpf: Move arena globals to the end of the arena") Signed-off-by: Emil Tsalapatis Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20260210184532.255475-1-emil@etsalapatis.com Signed-off-by: Alexei Starovoitov

libbpf: support llvm-generated indirect jumps

2025-11-06T01:53:23+00:00

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 Acked-by: Eduard Zingerman Link: https://lore.kernel.org/r/20251105090410.1250500-11-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov

libbpf: move libbpf_sha256() implementation into libbpf_utils.c

2025-10-01T22:27:25+00:00

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 Link: https://lore.kernel.org/r/20251001171326.3883055-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov Acked-by: Eduard Zingerman

libbpf: move libbpf_errstr() into libbpf_utils.c

2025-10-01T22:27:25+00:00

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 Link: https://lore.kernel.org/r/20251001171326.3883055-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov Acked-by: Eduard Zingerman

libbpf: Replace AF_ALG with open coded SHA-256

2025-09-28T11:25:31+00:00

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 Link: https://lore.kernel.org/r/20250928003833.138407-1-ebiggers@kernel.org Signed-off-by: Alexei Starovoitov

libbpf: Implement SHA256 internal helper

2025-09-19T02:11:42+00:00

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 Signed-off-by: KP Singh Link: https://lore.kernel.org/r/20250914215141.15144-4-kpsingh@kernel.org Signed-off-by: Alexei Starovoitov

libbpf: Fix implicit memfd_create() for bionic

2025-04-04T15:52:37+00:00

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20250330211325.530677-1-cmllamas@google.com