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2026-08-13bpftool: Fix double close in map dumpYuan Chen
map_dump() closes the map fd in its error path, and do_dump() then closes the same fd again after a successful dump. Closing an already closed fd leaves errno set to EBADF, which poisons later errno checks such as the batch file read check in do_batch(). Let do_dump() own the fd and remove the close from map_dump(). The same double-close pattern exists in do_show_subset(): both show_map_close_json() and show_map_close_plain() already close the fd, so drop the extra close() there as well. Also propagate the error when bpf_map_get_info_by_fd() fails on a subsequent map in do_dump(): set err = -1 before breaking out of the loop, so a later failure is not silently hidden after an earlier iteration succeeded. Fixes: 99f9863a0c45f ("bpftool: Match maps by name") Signed-off-by: Yuan Chen <chenyuan@kylinos.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260810142224.2907373-2-chenyuan_fl@163.com
2026-08-13bpftool: Generate skeleton for global percpu dataLeon Hwang
Enhance bpftool to generate skeletons that properly handle global percpu variables. The generated skeleton now includes a dedicated structure for percpu data, allowing users to initialize and access percpu variables more efficiently. For global percpu variables, the skeleton now includes a nested structure, e.g.: struct test_global_percpu_data { struct bpf_object_skeleton *skeleton; struct bpf_object *obj; struct { struct bpf_map *percpu; } maps; // ... struct test_global_percpu_data__percpu { int data; char run; struct { char set; int i; int nums[7]; } struct_data; int nums[7]; } *percpu; // ... }; * The "struct test_global_percpu_data__percpu *percpu" points to initialized data, which is actually "maps.percpu->mmaped". * Before loading the skeleton, updating the "struct test_global_percpu_data__percpu *percpu" modifies the initial value of the corresponding global percpu variables. * After loading the skeleton, "maps.percpu->mmaped" has been marked as read-only in libbpf. If users want to update the global percpu variables, they have to update the "maps.percpu" map instead. * For lightweight skeleton, "lskel->percpu" will be protected by "mprotect(p, sz, PROT_READ)". * For subskeleton, those variables of global percpu data will be skipped. Assisted-by: Codex:gpt-5.5-xhigh Signed-off-by: Leon Hwang <leon.hwang@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260813152324.97937-7-leon.hwang@linux.dev
2026-08-08bpf: Do not print a newline after disassembly in bpf_verbose_insn()Eduard Zingerman
At the moment there are more callsites that want bpf_verbose_insn() to not print a newline after the instruction, than callsites that want a newline. Drop '\n' from disasm.c. Non-functional change. The changes in bpftool are verified by writing a bpf program using a variety of instructions and comparing `prog dump xlated` output in the following modes: plain, opcodes, visual, visual opcodes. The output before and after the changes is identical. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <qmo@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20260807-static-zext-v4-1-b6c270013c77@gmail.com
2026-07-20bpftool: Skip prog/map that disappears while looking it up by nameJiayuan Chen
Looking up a prog or map by name walks the whole id space. There is a window between bpf_prog_get_next_id()/bpf_map_get_next_id() and getting an fd for that id in which an unrelated object can be freed, and the lookup then fails with ENOENT and aborts the whole command. Skip such ids and keep walking, the same way do_show() already does. Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://lore.kernel.org/bpf/20260720071520.396363-1-jiayuan.chen@linux.dev Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-08bpftool: Cover loader metadata with the program signatureDaniel Borkmann
bpftool_prog_sign() signed only the loader instructions. The metadata blob the loader installs was left to an in-loader hash check, which the kernel now performs at load time over insns || metadata. Sign that same concatenation: pass the metadata blob (gen_loader_opts data) through to bpftool_prog_sign() and feed insns || metadata to CMS_final(). The excl_prog_hash stays a digest of the instructions alone; it binds the metadata map to the loader and is matched against prog->digest by the verifier, independent of what the signature covers. The signed artifact is now plain data: both bytes the signature covers are embedded verbatim in the generated skeleton, so signing and verifying an lskel is an ordinary CMS operation that a signer or auditor can perform (or reproduce) offline, without analyzing loader bytecode to establish what the signature actually attests to. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260708075343.358712-6-daniel@iogearbox.net Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-08bpftool: Check EVP_Digest when computing excl_prog_hashDaniel Borkmann
bpftool_prog_sign() ignores the return value of EVP_Digest(). If the digest computation fails (context allocation failure, or a digest fetch failure under OpenSSL), EVP_Digest() returns 0 and leaves the output buffer untouched, but the function still reports success. Fixes: 40863f4d6ef2 ("bpftool: Add support for signing BPF programs") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260708075343.358712-5-daniel@iogearbox.net Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-02bpftool: Use btf_vlen()/btf_kind()/btf_kflag() helpers consistentlyluoliang
The btf_vlen(), btf_kind() and btf_kflag() inline helpers defined in tools/lib/bpf/btf.h are thin wrappers around the BTF_INFO_VLEN(), BTF_INFO_KIND() and BTF_INFO_KFLAG() UAPI macros - each one simply returns the corresponding macro applied to t->info. bpftool already uses these helpers in most places, but 13 call sites in btf.c and btf_dumper.c still open-code the raw macros. Use the helpers consistently, matching the rest of bpftool as well as libbpf. No functional change. Signed-off-by: Liang Luo <luoliang@kylinos.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260702012311.2265001-1-luoliang@kylinos.cn
2026-07-01bpftool: Add tracing_multi link info outputJiri Olsa
Adding bpftool support to show tracing_multi link details, the new output looks like: # bpftool link ... 61: tracing_multi prog 167 attach_type trace_fentry_multi btf_obj_id 1 count 3 btf_id addr cookie func [module] 92598 ffffffff825017c4 10 bpf_fentry_test1 92600 ffffffff82503814 30 bpf_fentry_test2 92601 ffffffff82503824 20 bpf_fentry_test3 pids test_progs(1540) Assisted-by: Codex:GPT-5 Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260629212208.895962-4-jolsa@kernel.org
2026-07-01tools/bpf/bpftool: Reset vmlinux BTF after struct_ops commandsYichong Chen
struct_ops frees the global btf_vmlinux object. In batch mode, a later struct_ops command can reuse stale state. Reset the BTF pointer and cached map info state. Fixes: 65c93628599d ("bpftool: Add struct_ops support") Signed-off-by: Yichong Chen <chenyichong@uniontech.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/9F9017160ABE125F+20260624025055.1574875-3-chenyichong@uniontech.com
2026-07-01tools/bpf/bpftool: Reset vmlinux BTF after map commandsYichong Chen
get_map_kv_btf() caches the vmlinux BTF object when a map uses btf_vmlinux_value_type_id. map dump released that object when the command completed, but left the global pointer stale. The same cached object can also be returned to print_key_value(), which freed it directly. That leaves btf_vmlinux dangling before the command cleanup path runs. Use free_map_kv_btf() for per-entry cleanup, and reset the cached btf_vmlinux pointer when the map command releases the object. This keeps batch mode from reusing a freed BTF object. Fixes: 4e1ea33292ff ("bpftool: Support dumping a map with btf_vmlinux_value_type_id") Signed-off-by: Yichong Chen <chenyichong@uniontech.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/9072F43B3F74DF91+20260624025055.1574875-2-chenyichong@uniontech.com
2026-07-01bpftool: Strip all -Wformat* flags from bootstrap libbpf buildAndrii Nakryiko
Commit 9080b97689db ("bpftool: Pass host flags to bootstrap libbpf") started building the bootstrap libbpf with HOST_CFLAGS, stripping the warning options that are unsuitable for that build by filtering out -W -Wall -Wextra -Wformat -Wformat-signedness. HOST_CFLAGS inherits EXTRA_WARNINGS, which includes -Wformat-security and -Wformat-y2k. The filter drops -Wall and -Wformat (the latter being what actually enables -Wformat), but leaves those two -Wformat-* children in LIBBPF_BOOTSTRAP_CFLAGS. Building the bootstrap libbpf with it then warns: cc1: warning: '-Wformat-y2k' ignored without '-Wformat' cc1: warning: '-Wformat-security' ignored without '-Wformat' The warning is easy to miss in an in-tree build: tools/lib/bpf/Makefile re-adds -Wall via "override CFLAGS += -Wall", which re-enables -Wformat for the libbpf objects, so only libbpf's feature-detection probe (which uses the passed CFLAGS verbatim) leaks the two warnings. The standalone libbpf Makefile (github.com/libbpf/libbpf, used by the bpftool mirror) instead uses "CFLAGS ?= ... -Wall", which the passed-in CFLAGS overrides, so -Wall is never re-added and every bootstrap object warns. Use a -Wformat% wildcard in the filter-out so the orphaned children are removed together with the parent. Fixes: 9080b97689db ("bpftool: Pass host flags to bootstrap libbpf") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260630205418.3483969-1-andrii@kernel.org
2026-06-21bpftool: Fix vmlinux BTF leak in cgroup commandsYichong Chen
bpftool cgroup show and tree call libbpf_find_kernel_btf() to resolve attach_btf names, but never release the returned BTF object. For cgroup tree, do_show_tree_fn() is called once for each cgroup visited by nftw(). When more than one cgroup has attached programs, each callback overwrites btf_vmlinux with a new object and loses the previous allocation. Load vmlinux BTF only once during a tree walk and release it when cgroup show or tree completes. Reset btf_vmlinux_id at the same time so batch mode starts with clean state. Fixes: 596f5fb2ea2a ("bpftool: implement cgroup tree for BPF_LSM_CGROUP") Signed-off-by: Yichong Chen <chenyichong@uniontech.com> Reviewed-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/24357C69B4405079+20260617090117.280222-1-chenyichong@uniontech.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-14bpftool: Append extra host flagsLeo Yan
Append HOST_EXTRACFLAGS to HOST_CFLAGS so that additional flags can be applied to the host compiler. Acked-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Leo Yan <leo.yan@arm.com> Link: https://lore.kernel.org/r/20260602-tools_build_fix_zero_init_bpf_only-v2-3-c76e5250ea1c@arm.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-14bpftool: Avoid adding EXTRA_CFLAGS to HOST_CFLAGSLeo Yan
Prepare for future changes where EXTRA_CFLAGS may include flags not applicable to the host compiler. Move the HOST_CFLAGS assignment before appending EXTRA_CFLAGS to CFLAGS so that HOST_CFLAGS does not inherit flags from EXTRA_CFLAGS. Acked-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Leo Yan <leo.yan@arm.com> Link: https://lore.kernel.org/r/20260602-tools_build_fix_zero_init_bpf_only-v2-2-c76e5250ea1c@arm.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-14bpftool: Pass host flags to bootstrap libbpfLeo Yan
bpftool builds a bootstrap libbpf with HOSTCC, but the libbpf submake can still inherit target build flags through CFLAGS. This can break cross builds when host objects are compiled with target-only options. Since HOST_CFLAGS contains warning options that are not suitable for building libbpf, use LIBBPF_BOOTSTRAP_CFLAGS with the warning options removed to build the bootstrap libbpf. Clear EXTRA_CFLAGS so target extra flags are not mixed into the host bootstrap libbpf build. Signed-off-by: Leo Yan <leo.yan@arm.com> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20260602-tools_build_fix_zero_init_bpf_only-v2-1-c76e5250ea1c@arm.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-05bpftool: Restrict feature tests during bootstrap compilationIan Rogers
When the perf build executes 'make -C ../bpf/bpftool bootstrap', bpftool's Makefile unconditionally evaluated feature checks for llvm, libcap, libbfd, and disassembler libraries because the bootstrap target was not exempted. Since the bootstrap bpftool strictly compiles minimal AST parsing and C code generation logic without linking LLVM or disassembler libraries, these feature check sub-makes are completely redundant. Exempt the bootstrap target from non-essential feature tests to eliminate unneeded sub-make fork overhead during Kbuild startup. Tested-by: James Clark <james.clark@linaro.org> Assisted-by: Gemini:gemini-3.1-pro-preview Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20260531010750.525160-1-irogers@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-05bpftool: Add rhash map documentationMykyta Yatsenko
Make bpftool documentation aware of the resizable hash map. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/r/20260605-rhash-v7-11-5b8e05f8630d@meta.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-03bpftool: Use libbpf error code for flow dissector queryWoojin Ji
bpf_prog_query() returns a negative errno on failure. query_flow_dissector() currently closes the namespace fd and then reads errno to decide whether -EINVAL means that the running kernel does not support flow dissector queries. That errno check controls behavior, not just diagnostics: -EINVAL is handled as a non-fatal old-kernel case, while any other error makes bpftool net fail. The namespace fd is opened read-only, so close() is not expected to commonly fail in normal use. Still, the BPF_PROG_QUERY error is already available in err, and reading errno after an intervening close() is fragile. If close() does change errno, the compatibility branch may be based on close()'s error instead of the BPF_PROG_QUERY result. This was reproduced with an LD_PRELOAD fault injector that forced BPF_PROG_QUERY for BPF_FLOW_DISSECTOR to fail with EINVAL and then forced close() on the netns fd to fail with EIO. The unpatched bpftool reported "can't query prog: Input/output error". With this change, the same injected failure is handled as the intended non-fatal EINVAL compatibility case. Use the libbpf-returned error code instead. Keep the existing errno reset in the non-fatal path to preserve batch mode behavior. The success path is unchanged. Fixes: 7f0c57fec80f ("bpftool: show flow_dissector attachment status") Signed-off-by: Woojin Ji <random6.xyz@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Leon Hwang <leon.hwang@linux.dev> Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260603003339.33791-1-random6.xyz@gmail.com Assisted-by: ChatGPT:gpt-5.5
2026-05-28bpftool: Fix typo in struct_ops map FD generation for light skeletonSiddharth Nayyar
When generating light skeletons for BPF programs containing struct_ops maps, bpftool incorrectly outputs a stray literal 't' instead of a tab character for the map file descriptor member in the links structure. This causes a compilation error when the generated light skeleton is used. Correct the format string by replacing 't' with '\t'. Fixes: 08ac454e258e ("libbpf: Auto-attach struct_ops BPF maps in BPF skeleton") Signed-off-by: Siddharth Nayyar <sidnayyar@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20260520-struct_ops_gen_typo_fix-v1-1-4dee3771da46@google.com
2026-04-20bpftool: Support 24-bit vlenAlan Maguire
Adjust btf_vlen() usage to handle 24-bit vlen. Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/r/20260417143023.1551481-4-alan.maguire@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-12bpftool: add missing fsession to the usage and docs of bpftoolMenglong Dong
Add the fsession attach type to the usage of bpftool in do_help(). Meanwhile, add it to the bash-completion and bpftool-prog.rst too. Acked-by: Leon Hwang <leon.hwang@linux.dev> Acked-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Link: https://lore.kernel.org/r/20260412060346.142007-4-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-03-24bpftool: Enable aarch64 ISA extensions for JIT disassemblyPuranjay Mohan
The LLVM disassembler needs ISA extension features enabled to correctly decode instructions from those extensions. On aarch64, without these features, instructions like LSE atomics (e.g. ldaddal) are silently decoded as incorrect instructions and disassembly is truncated. Use LLVMCreateDisasmCPUFeatures() with "+all" features for aarch64 targets so that the disassembler can handle any instruction the kernel JIT might emit. Before: int bench_trigger_uprobe(void * ctx): bpf_prog_538c6a43d1c6b84c_bench_trigger_uprobe: ; int cpu = bpf_get_smp_processor_id(); 0: mov x9, x30 4: nop 8: stp x29, x30, [sp, #-16]! c: mov x29, sp 10: stp xzr, x26, [sp, #-16]! 14: mov x26, sp 18: mrs x10, SP_EL0 1c: ldr w7, [x10, #16] ; __sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1); 20: and w7, w7, #0xff ; __sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1); 24: lsl x7, x7, #7 28: mov x0, #-281474976710656 2c: movk x0, #32768, lsl #32 30: movk x0, #35407, lsl #16 34: add x0, x0, x7 38: mov x1, #1 ; __sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1); 3c: mov x1, #1 After: int bench_trigger_uprobe(void * ctx): bpf_prog_538c6a43d1c6b84c_bench_trigger_uprobe: ; int cpu = bpf_get_smp_processor_id(); 0: mov x9, x30 4: nop 8: stp x29, x30, [sp, #-16]! c: mov x29, sp 10: stp xzr, x26, [sp, #-16]! 14: mov x26, sp 18: mrs x10, SP_EL0 1c: ldr w7, [x10, #16] ; __sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1); 20: and w7, w7, #0xff ; __sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1); 24: lsl x7, x7, #7 28: mov x0, #-281474976710656 2c: movk x0, #32768, lsl #32 30: movk x0, #35407, lsl #16 34: add x0, x0, x7 38: mov x1, #1 ; __sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1); 3c: ldaddal x1, x1, [x0] ; return 0; 40: mov w7, #0 44: ldp xzr, x26, [sp], #16 48: ldp x29, x30, [sp], #16 4c: mov x0, x7 50: ret 54: nop 58: ldr x10, #8 5c: br x10 Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Leon Hwang <leon.hwang@linux.dev> Acked-by: Quentin Monnet <qmo@kernel.org> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/r/20260318172259.2882792-1-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-03-16bpftool: Allow explicitly skip llvm, libbfd and libcrypto dependenciesMykyta Yatsenko
Introduce SKIP_LLVM, SKIP_LIBBFD, and SKIP_CRYPTO build flags that let users build bpftool without these optional dependencies. SKIP_LLVM=1 skips LLVM even when detected. SKIP_LIBBFD=1 prevents the libbfd JIT disassembly fallback when LLVM is absent. Together, they produce a bpftool with no disassembly support. SKIP_CRYPTO=1 excludes sign.c and removes the -lcrypto link dependency. Inline stubs in main.h return errors with a clear message if signing functions are called at runtime. Use BPFTOOL_WITHOUT_CRYPTO (not HAVE_LIBCRYPTO_SUPPORT) as the C define, following the BPFTOOL_WITHOUT_SKELETONS naming convention for bpftool-internal build config, leaving HAVE_LIBCRYPTO_SUPPORT free for proper feature detection in the future. All three flags are propagated through the selftests Makefile to bpftool sub-builds. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260312-b4-bpftool_build-v2-1-4c9d57133644@meta.com
2026-03-05bpftool: Support merging multiple module BTFs in btf dumpJosef Bacik
Add support for specifying multiple file sources in 'bpftool btf dump' to generate a single C header containing types from vmlinux plus multiple kernel modules: bpftool btf dump file /sys/kernel/btf/mod1 file /sys/kernel/btf/mod2 format c This is useful for BPF programs that need to access types defined in kernel modules. Previously this required a separate bpftool invocation for each module, producing separate headers that could not be combined due to overlapping vmlinux type definitions. The implementation collects all file paths, then for the multi-file case creates an empty split BTF on the vmlinux base and iteratively merges each module's types into it via btf__add_btf(). The single-file code path is preserved exactly to avoid any regression risk. Auto-detection of vmlinux as the base BTF from sysfs paths works as before. If vmlinux itself appears in the file list it is skipped with a warning since its types are already provided by the base. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/bpf/b19c2760ffe48cec546dd3810d237f8cad20d606.1772657690.git.josef@toxicpanda.com
2026-02-17bpftool: Fix truncated netlink dumpsJakub Kicinski
Netlink requires that the recv buffer used during dumps is at least min(PAGE_SIZE, 8k) (see the man page). Otherwise the messages will get truncated. Make sure bpftool follows this requirement, avoid missing information on systems with large pages. Acked-by: Quentin Monnet <qmo@kernel.org> Fixes: 7084566a236f ("tools/bpftool: Remove libbpf_internal.h usage in bpftool") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20260217194150.734701-1-kuba@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-01-28bpftool: Fix dependencies for static buildIhor Solodrai
When building selftests/bpf with EXTRA_LDFLAGS=-static the follwoing error happens: LINK /ws/linux/tools/testing/selftests/bpf/tools/build/bpftool/bootstrap/bpftool /usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/gcc/x86_64-linux-gnu/15/../../../x86_64-linux-gnu/libcrypto.a(libcrypto-lib-dso_dlfcn.o): in function `dlfcn_globallookup': [...] /usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/gcc/x86_64-linux-gnu/15/../../../x86_64-linux-gnu/libcrypto.a(libcrypto-lib-c_zlib.o): in function `zlib_oneshot_expand_block': (.text+0xc64): undefined reference to `uncompress' /usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/gcc/x86_64-linux-gnu/15/../../../x86_64-linux-gnu/libcrypto.a(libcrypto-lib-c_zlib.o): in function `zlib_oneshot_compress_block': (.text+0xce4): undefined reference to `compress' collect2: error: ld returned 1 exit status make[1]: *** [Makefile:252: /ws/linux/tools/testing/selftests/bpf/tools/build/bpftool/bootstrap/bpftool] Error 1 make: *** [Makefile:327: /ws/linux/tools/testing/selftests/bpf/tools/sbin/bpftool] Error 2 make: *** Waiting for unfinished jobs.... This is caused by wrong order of dependencies in the Makefile. Fix it. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260128211255.376933-1-ihor.solodrai@linux.dev
2026-01-24bpftool: add fsession supportMenglong Dong
Add BPF_TRACE_FSESSION to bpftool. Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Link: https://lore.kernel.org/r/20260124062008.8657-10-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-01-16bpftool: Add 'prepend' option for tcx attach to insert at chain startGyutae Bae
Add support for the 'prepend' option when attaching tcx_ingress and tcx_egress programs. This option allows inserting a BPF program at the beginning of the TCX chain instead of appending it at the end. The implementation uses BPF_F_BEFORE flag which automatically inserts the program at the beginning of the chain when no relative reference is specified. This change includes: - Modify do_attach_tcx() to support prepend insertion using BPF_F_BEFORE - Update documentation to describe the new 'prepend' option - Add bash completion support for the 'prepend' option on tcx attach types - Add example usage in the documentation - Add validation to reject 'overwrite' for non-XDP attach types The 'prepend' option is only valid for tcx_ingress and tcx_egress attach types. For XDP attach types, the existing 'overwrite' option remains available. Example usage: # bpftool net attach tcx_ingress name tc_prog dev lo prepend This feature is useful when the order of program execution in the TCX chain matters and users need to ensure certain programs run first. Co-developed-by: Siwan Kim <siwan.kim@navercorp.com> Signed-off-by: Siwan Kim <siwan.kim@navercorp.com> Signed-off-by: Gyutae Bae <gyutae.bae@navercorp.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Quentin Monnet <qmo@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20260112034516.22723-1-gyutae.opensource@navercorp.com
2026-01-09bpftool: Make skeleton C++ compatible with explicit castsWanLi Niu
Fix C++ compilation errors in generated skeleton by adding explicit pointer casts and use char * subtraction for offset calculation error: invalid conversion from 'void*' to '<obj_name>*' [-fpermissive] | skel = skel_alloc(sizeof(*skel)); | ~~~~~~~~~~^~~~~~~~~~~~~~~ | | | void* error: arithmetic on pointers to void | skel->ctx.sz = (void *)&skel->links - (void *)skel; | ~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~ error: assigning to 'struct <obj_name>__<ident> *' from incompatible type 'void *' | skel-><ident> = skel_prep_map_data((void *)data, 4096, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | sizeof(data) - 1); | ~~~~~~~~~~~~~~~~~ error: assigning to 'struct <obj_name>__<ident> *' from incompatible type 'void *' | skel-><ident> = skel_finalize_map_data(&skel->maps.<ident>.initial_value, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | 4096, PROT_READ | PROT_WRITE, skel->maps.<ident>.map_fd); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Minimum reproducer: $ cat test.bpf.c int val; // placed in .bss section #include "vmlinux.h" #include <bpf/bpf_helpers.h> SEC("raw_tracepoint/sched_wakeup_new") int handle(void *ctx) { return 0; } $ cat test.cpp #include <cerrno> extern "C" { #include "test.bpf.skel.h" } $ bpftool btf dump file /sys/kernel/btf/vmlinux format c > vmlinux.h $ clang -g -O2 -target bpf -c test.bpf.c -o test.bpf.o $ bpftool gen skeleton test.bpf.o -L > test.bpf.skel.h $ g++ -c test.cpp -I. Co-developed-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: WanLi Niu <niuwl1@chinatelecom.cn> Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260106023123.2928-1-kiraskyler@163.com
2025-12-09bpftool: Fix build warnings due to MS extensionsQuentin Monnet
The kernel is now built with -fms-extensions. Anonymous structs or unions permitted by these extensions have been used in several places, and can end up in the generated vmlinux.h file, for example: struct ns_tree { [...] }; [...] struct ns_common { [...] union { struct ns_tree; struct callback_head ns_rcu; }; }; Trying to include this header for compiling a tool may result in build warnings, if the compiler does not expect these extensions. This is the case, for example, with bpftool: In file included from skeleton/pid_iter.bpf.c:3: .../tools/testing/selftests/bpf/tools/build/bpftool/vmlinux.h:64057:3: warning: declaration does not declare anything [-Wmissing-declarations] 64057 | struct ns_tree; | ^~~~~~~~~~~~~~ Fix these build warnings in bpftool by turning on Microsoft extensions when compiling the two BPF programs that rely on vmlinux.h. Reported-by: Alexei Starovoitov <ast@kernel.org> Closes: https://lore.kernel.org/bpf/CAADnVQK9ZkPC7+R5VXKHVdtj8tumpMXm7BTp0u9CoiFLz_aPTg@mail.gmail.com/ Signed-off-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20251208130748.68371-1-qmo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-24bpftool: Allow bpftool to build with openssl < 3Alan Maguire
ERR_get_error_all()[1] is a openssl v3 API, so to make code compatible with openssl v1 utilize ERR_get_err_line_data instead. Since openssl is already a build requirement for the kernel (minimum requirement openssl 1.0.0), this will allow bpftool to compile where opensslv3 is not available. Signing-related BPF selftests pass with openssl v1. [1] https://docs.openssl.org/3.4/man3/ERR_get_error/ Fixes: 40863f4d6ef2 ("bpftool: Add support for signing BPF programs") Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Acked-by: Song Liu <song@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20251120084754.640405-2-alan.maguire@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after 6.18-rc5+Alexei Starovoitov
Cross-merge BPF and other fixes after downstream PR. Minor conflict in kernel/bpf/helpers.c Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-05bpftool: Recognize insn_array map typeAnton Protopopov
Teach bpftool to recognize instruction array map type. Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20251105090410.1250500-3-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-04bpf: add _impl suffix for bpf_stream_vprintk() kfuncMykyta Yatsenko
Rename bpf_stream_vprintk() to bpf_stream_vprintk_impl(). This makes bpf_stream_vprintk() follow the already established "_impl" suffix-based naming convention for kfuncs with the bpf_prog_aux argument provided by the verifier implicitly. This convention will be taken advantage of with the upcoming KF_IMPLICIT_ARGS feature to preserve backwards compatibility to BPF programs. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Link: https://lore.kernel.org/r/20251104-implv2-v3-2-4772b9ae0e06@meta.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Ihor Solodrai <ihor.solodrai@linux.dev>
2025-10-28bpftool: Fix missing closing parethesis for BTF_KIND_UNKNZhang Chujun
In the btf_dumper_do_type function, the debug print statement for BTF_KIND_UNKN was missing a closing parenthesis in the output format. This patch adds the missing ')' to ensure proper formatting of the dump output. Signed-off-by: Zhang Chujun <zhangchujun@cmss.chinamobile.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20251028063345.1911-1-zhangchujun@cmss.chinamobile.com
2025-09-27bpftool: Remove duplicate string.h headerJiapeng Chong
./tools/bpf/bpftool/sign.c: string.h is included more than once. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=25502 Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20250926095240.3397539-2-jiapeng.chong@linux.alibaba.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-23bpftool: Add bash completion for program signing optionsQuentin Monnet
Commit 40863f4d6ef2 ("bpftool: Add support for signing BPF programs") added new options for "bpftool prog load" and "bpftool gen skeleton". This commit brings the relevant update to the bash completion file. We rework slightly the processing of options to make completion more resilient for options that take an argument. Signed-off-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20250923103802.57695-1-qmo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-22bpftool: Add support for signing BPF programsKP Singh
Two modes of operation being added: Add two modes of operation: * For prog load, allow signing a program immediately before loading. This is essential for command-line testing and administration. bpftool prog load -S -k <private_key> -i <identity_cert> fentry_test.bpf.o * For gen skeleton, embed a pre-generated signature into the C skeleton file. This supports the use of signed programs in compiled applications. bpftool gen skeleton -S -k <private_key> -i <identity_cert> fentry_test.bpf.o Generation of the loader program and its metadata map is implemented in libbpf (bpf_obj__gen_loader). bpftool generates a skeleton that loads the program and automates the required steps: freezing the map, creating an exclusive map, loading, and running. Users can use standard libbpf APIs directly or integrate loader program generation into their own toolchains. Signed-off-by: KP Singh <kpsingh@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20250921160120.9711-5-kpsingh@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-19bpftool: Fix -Wuninitialized-const-pointer warnings with clang >= 21Tom Stellard
This fixes the build with -Werror -Wall. btf_dumper.c:71:31: error: variable 'finfo' is uninitialized when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer] 71 | info.func_info = ptr_to_u64(&finfo); | ^~~~~ prog.c:2294:31: error: variable 'func_info' is uninitialized when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer] 2294 | info.func_info = ptr_to_u64(&func_info); | v2: - Initialize instead of using memset. Signed-off-by: Tom Stellard <tstellar@redhat.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20250917183847.318163-1-tstellar@redhat.com
2025-09-19bpftool: Fix UAF in get_delegate_valueTao Chen
The return value ret pointer is pointing opts_copy, but opts_copy gets freed in get_delegate_value before return, fix this by free the mntent->mnt_opts strdup memory after show delegate value. Fixes: 2d812311c2b2 ("bpftool: Add bpf_token show") Signed-off-by: Tao Chen <chen.dylane@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20250919034816.1287280-2-chen.dylane@linux.dev
2025-09-19bpftool: Add HELP_SPEC_OPTIONS in token.cTao Chen
$ ./bpftool token help Usage: bpftool token { show | list } bpftool token help OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} } Fixes: 2d812311c2b2 ("bpftool: Add bpf_token show") Signed-off-by: Tao Chen <chen.dylane@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/bpf/20250919034816.1287280-1-chen.dylane@linux.dev
2025-09-15bpftool: Search for tracefs at /sys/kernel/tracing firstQuentin Monnet
With "bpftool prog tracelog", bpftool prints messages from the trace pipe. To do so, it first needs to find the tracefs mount point to open the pipe. Bpftool looks at a few "default" locations, including /sys/kernel/debug/tracing and /sys/kernel/tracing. Some of these locations, namely /tracing and /trace, are not standard. They are in the list because some users used to hardcode the tracing directory to short names; but we have no compelling reason to look at these locations. If we fail to find the tracefs at the default locations, we have an additional step to find it by parsing /proc/mounts anyway, so it's safe to remove these entries from the list of default locations to check. Additionally, Alexei reports that looking for the tracefs at /sys/kernel/debug/tracing may automatically mount the file system under that location, and generate a kernel log message telling that auto-mounting there is deprecated. To avoid this message, let's swap the order for checking the potential mount points: try /sys/kernel/tracing first, which should be the standard location nowadays. The kernel log message may still appear if the tracefs is not mounted on /sys/kernel/tracing when we run bpftool. Reported-by: Alexei Starovoitov <ast@kernel.org> Closes: https://lore.kernel.org/r/CAADnVQLcMi5YQhZKsU4z3S2uVUAGu_62C33G2Zx_ruG3uXa-Ug@mail.gmail.com/ Signed-off-by: Quentin Monnet <qmo@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20250915134209.36568-1-qmo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-02bpftool: Add CET-aware symbol matching for x86_64 architecturesYuan Chen
Adjust symbol matching logic to account for Control-flow Enforcement Technology (CET) on x86_64 systems. CET prefixes functions with a 4-byte 'endbr' instruction, shifting the actual hook entry point to symbol + 4. Signed-off-by: Yuan Chen <chenyuan@kylinos.cn> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <qmo@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20250829061107.23905-3-chenyuan_fl@163.com
2025-09-02bpftool: Refactor kernel config reading into common helperYuan Chen
Extract the kernel configuration file parsing logic from feature.c into a new read_kernel_config() function in common.c. This includes: 1. Moving the config file handling and option parsing code 2. Adding required headers and struct definition 3. Keeping all existing functionality The refactoring enables sharing this logic with other components while maintaining current behavior. This will be used by subsequent patches that need to check kernel config options. Signed-off-by: Yuan Chen <chenyuan@kylinos.cn> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <qmo@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20250829061107.23905-2-chenyuan_fl@163.com
2025-08-19bpftool: Add kernel.kptr_restrict hint for no instructionsVincent Li
From bpftool's github repository issue [0]: When a Linux distribution has the kernel.kptr_restrict set to 2, bpftool prog dump jited returns "no instructions returned". This message can be puzzling to bpftool users who are not familiar with kernel BPF internals, so add a small hint for bpftool users to check the kernel.kptr_restrict setting similar to the DUMP_XLATED case. Outside of kernel.kptr_restrict, no instructions could also be returned in case the JIT was disabled. Signed-off-by: Vincent Li <vincent.mc.li@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://github.com/libbpf/bpftool/issues/184 [0] Link: https://lore.kernel.org/bpf/20250818165113.15982-1-vincent.mc.li@gmail.com
2025-08-01bpftool: Add bash completion for token argumentTao Chen
This commit updates the bash completion script with the new token argument. $ bpftool token help list show Reviewed-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Tao Chen <chen.dylane@linux.dev> Link: https://lore.kernel.org/r/20250723144442.1427943-3-chen.dylane@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-01bpftool: Add bpftool-token manpageTao Chen
Add bpftool-token manpage with information and examples of token-related commands. Suggested-by: Quentin Monnet <qmo@kernel.org> Reviewed-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Tao Chen <chen.dylane@linux.dev> Link: https://lore.kernel.org/r/20250723144442.1427943-2-chen.dylane@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-08-01bpftool: Add bpf_token showTao Chen
Add `bpftool token show` command to get token info from bpffs in /proc/mounts. Example plain output for `token show`: token_info /sys/fs/bpf/token allowed_cmds: map_create prog_load allowed_maps: allowed_progs: kprobe allowed_attachs: xdp token_info /sys/fs/bpf/token2 allowed_cmds: map_create prog_load allowed_maps: allowed_progs: kprobe allowed_attachs: xdp Example json output for `token show`: [{ "token_info": "/sys/fs/bpf/token", "allowed_cmds": ["map_create", "prog_load"], "allowed_maps": [], "allowed_progs": ["kprobe"], "allowed_attachs": ["xdp"] }, { "token_info": "/sys/fs/bpf/token2", "allowed_cmds": ["map_create", "prog_load"], "allowed_maps": [], "allowed_progs": ["kprobe"], "allowed_attachs": ["xdp"] }] Reviewed-by: Quentin Monnet <qmo@kernel.org> Signed-off-by: Tao Chen <chen.dylane@linux.dev> Link: https://lore.kernel.org/r/20250723144442.1427943-1-chen.dylane@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-03bpftool: Add support for dumping streamsKumar Kartikeya Dwivedi
Add support for printing the BPF stream contents of a program in bpftool. The new bpftool prog tracelog command is extended to take stdout and stderr arguments, and then the prog specification. The bpf_prog_stream_read() API added in previous patch is simply reused to grab data and then it is dumped to the respective file. The stdout data is sent to stdout, and stderr is printed to stderr. Cc: Quentin Monnet <qmo@kernel.org> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20250703204818.925464-12-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-20bpftool: Fix memory leak in dump_xx_nlmsg on realloc failureYuan Chen
In function dump_xx_nlmsg(), when realloc() fails to allocate memory, the original pointer to the buffer is overwritten with NULL. This causes a memory leak because the previously allocated buffer becomes unreachable without being freed. Fixes: 7900efc19214 ("tools/bpf: bpftool: improve output format for bpftool net") Signed-off-by: Yuan Chen <chenyuan@kylinos.cn> Reviewed-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20250620012133.14819-1-chenyuan_fl@163.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
generated by cgit v1.2.3 (git 2.25.1) at 2026-09-07 01:46:47 +0000