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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
2025-03-15libbpf: Split bpf object load into prepare/loadMykyta Yatsenko
Introduce bpf_object__prepare API: additional intermediate preparation step that performs ELF processing, relocations, prepares final state of BPF program instructions (accessible with bpf_program__insns()), creates and (potentially) pins maps, and stops short of loading BPF programs. We anticipate few use cases for this API, such as: * Use prepare to initialize bpf_token, without loading freplace programs, unlocking possibility to lookup BTF of other programs. * Execute prepare to obtain finalized BPF program instructions without loading programs, enabling tools like veristat to process one program at a time, without incurring cost of ELF parsing and processing. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250303135752.158343-4-mykyta.yatsenko5@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-03-15libbpf: Introduce more granular state for bpf_objectMykyta Yatsenko
We are going to split bpf_object loading into 2 stages: preparation and loading. This will increase flexibility when working with bpf_object and unlock some optimizations and use cases. This patch substitutes a boolean flag (loaded) by more finely-grained state for bpf_object. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250303135752.158343-3-mykyta.yatsenko5@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-03-15libbpf: Use map_is_created helper in map settersMykyta Yatsenko
Refactoring: use map_is_created helper in map setters that need to check the state of the map. This helps to reduce the number of the places that depend explicitly on the loaded flag, simplifying refactoring in the next patch of this set. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250303135752.158343-2-mykyta.yatsenko5@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-26libbpf: Implement bpf_usdt_arg_size BPF functionIhor Solodrai
Information about USDT argument size is implicitly stored in __bpf_usdt_arg_spec, but currently it's not accessbile to BPF programs that use USDT. Implement bpf_sdt_arg_size() that returns the size of an USDT argument in bytes. v1->v2: * do not add __bpf_usdt_arg_spec() helper v1: https://lore.kernel.org/bpf/20250220215904.3362709-1-ihor.solodrai@linux.dev/ Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20250224235756.2612606-1-ihor.solodrai@linux.dev
2025-02-25Merge tag 'perf-tools-fixes-for-v6.14-2-2025-02-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools fixes from Arnaldo Carvalho de Melo: - Fix tools/ quiet build Makefile infrastructure that was broken when working on tools/perf/ without testing on other tools/ living utilities. * tag 'perf-tools-fixes-for-v6.14-2-2025-02-25' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: tools: Remove redundant quiet setup tools: Unify top-level quiet infrastructure
2025-02-24libbpf: Fix out-of-bound readNandakumar Edamana
In `set_kcfg_value_str`, an untrusted string is accessed with the assumption that it will be at least two characters long due to the presence of checks for opening and closing quotes. But the check for the closing quote (value[len - 1] != '"') misses the fact that it could be checking the opening quote itself in case of an invalid input that consists of just the opening quote. This commit adds an explicit check to make sure the string is at least two characters long. Signed-off-by: Nandakumar Edamana <nandakumar@nandakumar.co.in> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250221210110.3182084-1-nandakumar@nandakumar.co.in
2025-02-20libbpf: Fix hypothetical STT_SECTION extern NULL deref caseAndrii Nakryiko
Fix theoretical NULL dereference in linker when resolving *extern* STT_SECTION symbol against not-yet-existing ELF section. Not sure if it's possible in practice for valid ELF object files (this would require embedded assembly manipulations, at which point BTF will be missing), but fix the s/dst_sym/dst_sec/ typo guarding this condition anyways. Fixes: faf6ed321cf6 ("libbpf: Add BPF static linker APIs") Fixes: a46349227cd8 ("libbpf: Add linker extern resolution support for functions and global variables") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20250220002821.834400-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-19libbpf: Wrap libbpf API direct err with libbpf_errTao Chen
Just wrap the direct err with libbpf_err, keep consistency with other APIs. Signed-off-by: Tao Chen <chen.dylane@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20250219153711.29651-1-chen.dylane@linux.dev
2025-02-18tools: Remove redundant quiet setupCharlie Jenkins
Q is exported from Makefile.include so it is not necessary to manually set it. Reviewed-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Benjamin Tissoires <bentiss@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Lukasz Luba <lukasz.luba@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Mykola Lysenko <mykolal@fb.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: Zhang Rui <rui.zhang@intel.com> Link: https://lore.kernel.org/r/20250213-quiet_tools-v3-2-07de4482a581@rivosinc.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-02-14libbpf: fix LDX/STX/ST CO-RE relocation size adjustment logicAndrii Nakryiko
Libbpf has a somewhat obscure feature of automatically adjusting the "size" of LDX/STX/ST instruction (memory store and load instructions), based on originally recorded access size (u8, u16, u32, or u64) and the actual size of the field on target kernel. This is meant to facilitate using BPF CO-RE on 32-bit architectures (pointers are always 64-bit in BPF, but host kernel's BTF will have it as 32-bit type), as well as generally supporting safe type changes (unsigned integer type changes can be transparently "relocated"). One issue that surfaced only now, 5 years after this logic was implemented, is how this all works when dealing with fields that are arrays. This isn't all that easy and straightforward to hit (see selftests that reproduce this condition), but one of sched_ext BPF programs did hit it with innocent looking loop. Long story short, libbpf used to calculate entire array size, instead of making sure to only calculate array's element size. But it's the element that is loaded by LDX/STX/ST instructions (1, 2, 4, or 8 bytes), so that's what libbpf should check. This patch adjusts the logic for arrays and fixed the issue. Reported-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/r/20250207014809.1573841-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-05libbpf: Check the kflag of type tags in btf_dumpIhor Solodrai
If the kflag is set for a BTF type tag, then the tag represents an arbitrary __attribute__. Change btf_dump accordingly. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250130201239.1429648-4-ihor.solodrai@linux.dev
2025-02-05libbpf: Introduce kflag for type_tags and decl_tags in BTFIhor Solodrai
Add the following functions to libbpf API: * btf__add_type_attr() * btf__add_decl_attr() These functions allow to add to BTF the type tags and decl tags with info->kflag set to 1. The kflag indicates that the tag directly encodes an __attribute__ and not a normal tag. See Documentation/bpf/btf.rst changes in the subsequent patch for details on the semantics. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250130201239.1429648-2-ihor.solodrai@linux.dev
2025-02-03libbpf: Fix accessing BTF.ext core_relo headerTony Ambardar
Update btf_ext_parse_info() to ensure the core_relo header is present before reading its fields. This avoids a potential buffer read overflow reported by the OSS Fuzz project. Fixes: cf579164e9ea ("libbpf: Support BTF.ext loading and output in either endianness") Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://issues.oss-fuzz.com/issues/388905046 Link: https://lore.kernel.org/bpf/20250125065236.2603346-1-itugrok@yahoo.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-01-17libbpf: Work around kernel inconsistently stripping '.llvm.' suffixAndrii Nakryiko
Some versions of kernel were stripping out '.llvm.<hash>' suffix from kerne symbols (produced by Clang LTO compilation) from function names reported in available_filter_functions, while kallsyms reported full original name. This confuses libbpf's multi-kprobe logic of finding all matching kernel functions for specified user glob pattern by joining available_filter_functions and kallsyms contents, because joining by full symbol name won't work for symbols containing '.llvm.<hash>' suffix. This was eventually fixed by [0] in the kernel, but we'd like to not regress multi-kprobe experience and add a work around for this bug on libbpf side, stripping kallsym's name if it matches user pattern and contains '.llvm.' suffix. [0] fb6a421fb615 ("kallsyms: Match symbols exactly with CONFIG_LTO_CLANG") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20250117003957.179331-1-andrii@kernel.org
2025-01-16libbpf: Fix incorrect traversal end type ID when marking BTF_IS_EMBEDDEDPu Lehui
When redirecting the split BTF to the vmlinux base BTF, we need to mark the distilled base struct/union members of split BTF structs/unions in id_map with BTF_IS_EMBEDDED. This indicates that these types must match both name and size later. Therefore, we need to traverse the entire split BTF, which involves traversing type IDs from nr_dist_base_types to nr_types. However, the current implementation uses an incorrect traversal end type ID, so let's correct it. Fixes: 19e00c897d50 ("libbpf: Split BTF relocation") Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250115100241.4171581-3-pulehui@huaweicloud.com
2025-01-16libbpf: Fix return zero when elf_begin failedPu Lehui
The error number of elf_begin is omitted when encapsulating the btf_find_elf_sections function. Fixes: c86f180ffc99 ("libbpf: Make btf_parse_elf process .BTF.base transparently") Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250115100241.4171581-2-pulehui@huaweicloud.com
2025-01-10libbpf: Add unique_match option for multi kprobeYonghong Song
Jordan reported an issue in Meta production environment where func try_to_wake_up() is renamed to try_to_wake_up.llvm.<hash>() by clang compiler at lto mode. The original 'kprobe/try_to_wake_up' does not work any more since try_to_wake_up() does not match the actual func name in /proc/kallsyms. There are a couple of ways to resolve this issue. For example, in attach_kprobe(), we could do lookup in /proc/kallsyms so try_to_wake_up() can be replaced by try_to_wake_up.llvm.<hach>(). Or we can force users to use bpf_program__attach_kprobe() where they need to lookup /proc/kallsyms to find out try_to_wake_up.llvm.<hach>(). But these two approaches requires extra work by either libbpf or user. Luckily, suggested by Andrii, multi kprobe already supports wildcard ('*') for symbol matching. In the above example, 'try_to_wake_up*' can match to try_to_wake_up() or try_to_wake_up.llvm.<hash>() and this allows bpf prog works for different kernels as some kernels may have try_to_wake_up() and some others may have try_to_wake_up.llvm.<hash>(). The original intention is to kprobe try_to_wake_up() only, so an optional field unique_match is added to struct bpf_kprobe_multi_opts. If the field is set to true, the number of matched functions must be one. Otherwise, the attachment will fail. In the above case, multi kprobe with 'try_to_wake_up*' and unique_match preserves user functionality. Reported-by: Jordan Rome <linux@jordanrome.com> Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250109174023.3368432-1-yonghong.song@linux.dev
2024-12-30libbpf: Set MFD_NOEXEC_SEAL when creating memfdDaniel Xu
Starting from 105ff5339f49 ("mm/memfd: add MFD_NOEXEC_SEAL and MFD_EXEC") and until 1717449b4417 ("memfd: drop warning for missing exec-related flags"), the kernel would print a warning if neither MFD_NOEXEC_SEAL nor MFD_EXEC is set in memfd_create(). If libbpf runs on on a kernel between these two commits (eg. on an improperly backported system), it'll trigger this warning. To avoid this warning (and also be more secure), explicitly set MFD_NOEXEC_SEAL. But since libbpf can be run on potentially very old kernels, leave a fallback for kernels without MFD_NOEXEC_SEAL support. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Link: https://lore.kernel.org/r/6e62c2421ad7eb1da49cbf16da95aaaa7f94d394.1735594195.git.dxu@dxuuu.xyz Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-12-13libbpf: prog load: Allow to use fd_array_cntAnton Protopopov
Add new fd_array_cnt field to bpf_prog_load_opts and pass it in bpf_attr, if set. Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241213130934.1087929-6-aspsk@isovalent.com
2024-12-12libbpf: Extend linker API to support in-memory ELF filesAlastair Robertson
The new_fd and add_fd functions correspond to the original new and add_file functions, but accept an FD instead of a file name. This gives API consumers the option of using anonymous files/memfds to avoid writing ELFs to disk. This new API will be useful for performing linking as part of bpftrace's JIT compilation. The add_buf function is a convenience wrapper that does the work of creating a memfd for the caller. Signed-off-by: Alastair Robertson <ajor@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241211164030.573042-3-ajor@meta.com
2024-12-12libbpf: Pull file-opening logic up to top-level functionsAlastair Robertson
Move the filename arguments and file-descriptor handling from init_output_elf() and linker_load_obj_file() and instead handle them at the top-level in bpf_linker__new() and bpf_linker__add_file(). This will allow the inner functions to be shared with a new, non-filename-based, API in the next commit. Signed-off-by: Alastair Robertson <ajor@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241211164030.573042-2-ajor@meta.com
2024-12-05libbpf: Fix segfault due to libelf functions not setting errnoQuentin Monnet
Libelf functions do not set errno on failure. Instead, it relies on its internal _elf_errno value, that can be retrieved via elf_errno (or the corresponding message via elf_errmsg()). From "man libelf": If a libelf function encounters an error it will set an internal error code that can be retrieved with elf_errno. Each thread maintains its own separate error code. The meaning of each error code can be determined with elf_errmsg, which returns a string describing the error. As a consequence, libbpf should not return -errno when a function from libelf fails, because an empty value will not be interpreted as an error and won't prevent the program to stop. This is visible in bpf_linker__add_file(), for example, where we call a succession of functions that rely on libelf: err = err ?: linker_load_obj_file(linker, filename, opts, &obj); err = err ?: linker_append_sec_data(linker, &obj); err = err ?: linker_append_elf_syms(linker, &obj); err = err ?: linker_append_elf_relos(linker, &obj); err = err ?: linker_append_btf(linker, &obj); err = err ?: linker_append_btf_ext(linker, &obj); If the object file that we try to process is not, in fact, a correct object file, linker_load_obj_file() may fail with errno not being set, and return 0. In this case we attempt to run linker_append_elf_sysms() and may segfault. This can happen (and was discovered) with bpftool: $ bpftool gen object output.o sample_ret0.bpf.c libbpf: failed to get ELF header for sample_ret0.bpf.c: invalid `Elf' handle zsh: segmentation fault (core dumped) bpftool gen object output.o sample_ret0.bpf.c Fix the issue by returning a non-null error code (-EINVAL) when libelf functions fail. Fixes: faf6ed321cf6 ("libbpf: Add BPF static linker APIs") Signed-off-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241205135942.65262-1-qmo@kernel.org
2024-12-02libbpf: Improve debug message when the base BTF cannot be foundBen Olson
When running `bpftool` on a kernel module installed in `/lib/modules...`, this error is encountered if the user does not specify `--base-btf` to point to a valid base BTF (e.g. usually in `/sys/kernel/btf/vmlinux`). However, looking at the debug output to determine the cause of the error simply says `Invalid BTF string section`, which does not point to the actual source of the error. This just improves that debug message to tell users what happened. Signed-off-by: Ben Olson <matthew.olson@intel.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/Z0YqzQ5lNz7obQG7@bolson-desk Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-12-02libbpf: don't adjust USDT semaphore address if .stapsdt.base addr is missingAndrii Nakryiko
USDT ELF note optionally can record an offset of .stapsdt.base, which is used to make adjustments to USDT target attach address. Currently, libbpf will do this address adjustment unconditionally if it finds .stapsdt.base ELF section in target binary. But there is a corner case where .stapsdt.base ELF section is present, but specific USDT note doesn't reference it. In such case, libbpf will basically just add base address and end up with absolutely incorrect USDT target address. This adjustment has to be done only if both .stapsdt.sema section is present and USDT note is recording a reference to it. Fixes: 74cc6311cec9 ("libbpf: Add USDT notes parsing and resolution logic") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20241121224558.796110-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-11-16libbpf: Change hash_combine parameters from long to unsigned longSidong Yang
The hash_combine() could be trapped when compiled with sanitizer like "zig cc" or clang with signed-integer-overflow option. This patch parameters and return type to unsigned long to remove the potential overflow. Signed-off-by: Sidong Yang <sidong.yang@furiosa.ai> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20241116081054.65195-1-sidong.yang@furiosa.ai Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-11-15libbpf: Fix memory leak in bpf_program__attach_uprobe_multiJiri Olsa
Andrii reported memory leak detected by Coverity on error path in bpf_program__attach_uprobe_multi. Fixing that by moving the check earlier before the offsets allocations. Reported-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241115115843.694337-1-jolsa@kernel.org
2024-11-11libbpf: Stringify errno in log messages in the remaining codeMykyta Yatsenko
Convert numeric error codes into the string representations in log messages in the rest of libbpf source files. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241111212919.368971-5-mykyta.yatsenko5@gmail.com
2024-11-11libbpf: Stringify errno in log messages in btf*.cMykyta Yatsenko
Convert numeric error codes into the string representations in log messages in btf.c and btf_dump.c. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241111212919.368971-4-mykyta.yatsenko5@gmail.com
2024-11-11libbpf: Stringify errno in log messages in libbpf.cMykyta Yatsenko
Convert numeric error codes into the string representations in log messages in libbpf.c. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241111212919.368971-3-mykyta.yatsenko5@gmail.com