linux/tools/lib/bpf, branch v6.17

libbpf: Add the ability to suppress perf event enablement

2025-08-07T16:01:41Z

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 Suggested-by: Jiri Olsa Tested-by: Thomas Richter Co-developed-by: Thomas Richter Signed-off-by: Thomas Richter Signed-off-by: Ilya Leoshkevich Link: https://lore.kernel.org/r/20250806162417.19666-2-iii@linux.ibm.com Signed-off-by: Alexei Starovoitov

libbpf: Avoid possible use of uninitialized mod_len

2025-07-31T18:39:46Z

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 Acked-by: Yonghong Song Acked-by: Eduard Zingerman Link: https://lore.kernel.org/r/20250729094611.2065713-1-fossdd@pwned.life Signed-off-by: Alexei Starovoitov

libbpf: Verify that arena map exists when adding arena relocations

2025-07-19T00:12:50Z

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20250718222059.281526-1-eddyz87@gmail.com

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc6

2025-07-18T19:15:59Z

Cross-merge BPF and other fixes after downstream PR. No conflicts. Signed-off-by: Alexei Starovoitov

libbpf: Fix warning in calloc() usage

2025-07-18T15:29:50Z

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 Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20250717200337.49168-1-technoboy85@gmail.com

libbpf: Fix handling of BPF arena relocations

2025-07-18T02:17:46Z

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 Tested-by: Eduard Zingerman Link: https://lore.kernel.org/r/20250718001009.610955-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov

libbpf: start v1.7 dev cycle

2025-07-17T01:37:27Z

With libbpf 1.6.0 released, adjust libbpf.map and libbpf_version.h to start v1.7 development cycles. Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20250716175936.2343013-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov

libbpf: __arg_untrusted in bpf_helpers.h

2025-07-07T15:25:07Z

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 Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20250704230354.1323244-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov

libbpf: Introduce bpf_prog_stream_read() API

2025-07-04T02:30:07Z

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 Acked-by: Eduard Zingerman Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20250703204818.925464-11-memxor@gmail.com Signed-off-by: Alexei Starovoitov

libbpf: Add bpf_stream_printk() macro

2025-07-04T02:30:07Z

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 Acked-by: Eduard Zingerman Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20250703204818.925464-10-memxor@gmail.com Signed-off-by: Alexei Starovoitov