From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED0DB1A6803; Tue, 16 Jun 2026 17:23:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781630596; cv=none; b=lVwQwhShrc88yJta5BLEyQzJYuPUoQOeAQlGsQzsg/3tx5Oup3/ckT1bhswL+/QjNhH+dUTvBoLCPjo/a8PObTLS7RFU4z5SjhrPdCV+enmh5lxst5kOkFb2P5so+mDWV3b4Qtro8s6idQHXoXYzUgZ2EaOkjXCSkfvl78T8CgI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781630596; c=relaxed/simple; bh=7CyMGBwKuNq+UBX0z5mgzusLurkVrL1uu20KbthexVc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hquMrH6grZfqNoLIysMZ0pBtZnlauzKnkFELbfSoCBTRqVV6k9oUnxOqDhhKaoE+Tpuibrwk3hd0abCbhQEelcRqeHPMFtxw6AwexY7hDwNs0KxDjRuF6gY3f9PnK/QAVtDNbkP6+NyGiYIUEri/jC3wTrRxEW1AY7TxCgsFggw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NHQbGxcH; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="NHQbGxcH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E00251F000E9; Tue, 16 Jun 2026 17:23:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781630594; bh=/O1nIiXq7m8eECmpSTDRR13dzuN4VnLwVSmn6mFTqxM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NHQbGxcH2IgVyXBppX6nPUTQFRcrT0ZrfVrSJDX6HWhTzOWe/GTBpAcN/TVk4RmrE DOUaF9aH8FRGPqIwh/e//5SADyi0Sgnk0nsYY1dHdPcH7vI6FXDTUzobF5bm5WCI6x MuEzDa7WNkPY8Tp6yFwdV3nnfs0nUWPwXZbh2JtE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jiri Olsa , Alexei Starovoitov , Paul Chaignon , Shung-Hsi Yu , Sasha Levin Subject: [PATCH 6.1 058/522] selftests/bpf: Add read_build_id function Date: Tue, 16 Jun 2026 20:23:25 +0530 Message-ID: <20260616145128.496758161@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145125.307082728@linuxfoundation.org> References: <20260616145125.307082728@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Olsa [ Upstream commit 88dc8b3605b38a440fba45edcc53a6c7a98eee3b ] Adding read_build_id function that parses out build id from specified binary. It will replace extract_build_id and also be used in following changes. Signed-off-by: Jiri Olsa Link: https://lore.kernel.org/r/20230331093157.1749137-3-jolsa@kernel.org Signed-off-by: Alexei Starovoitov Fixes: be4e85369e5a ("selftests/bpf: Replace extract_build_id with read_build_id") Signed-off-by: Paul Chaignon Acked-by: Shung-Hsi Yu Signed-off-by: Sasha Levin --- tools/testing/selftests/bpf/trace_helpers.c | 82 +++++++++++++++++++++ tools/testing/selftests/bpf/trace_helpers.h | 5 ++ 2 files changed, 87 insertions(+) diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c index 9c4be2cdb21a02..afc33ba36ccc6e 100644 --- a/tools/testing/selftests/bpf/trace_helpers.c +++ b/tools/testing/selftests/bpf/trace_helpers.c @@ -11,6 +11,9 @@ #include #include #include "trace_helpers.h" +#include +#include +#include #define DEBUGFS "/sys/kernel/debug/tracing/" @@ -224,3 +227,82 @@ ssize_t get_rel_offset(uintptr_t addr) fclose(f); return -EINVAL; } + +static int +parse_build_id_buf(const void *note_start, Elf32_Word note_size, char *build_id) +{ + Elf32_Word note_offs = 0; + + while (note_offs + sizeof(Elf32_Nhdr) < note_size) { + Elf32_Nhdr *nhdr = (Elf32_Nhdr *)(note_start + note_offs); + + if (nhdr->n_type == 3 && nhdr->n_namesz == sizeof("GNU") && + !strcmp((char *)(nhdr + 1), "GNU") && nhdr->n_descsz > 0 && + nhdr->n_descsz <= BPF_BUILD_ID_SIZE) { + memcpy(build_id, note_start + note_offs + + ALIGN(sizeof("GNU"), 4) + sizeof(Elf32_Nhdr), nhdr->n_descsz); + memset(build_id + nhdr->n_descsz, 0, BPF_BUILD_ID_SIZE - nhdr->n_descsz); + return (int) nhdr->n_descsz; + } + + note_offs = note_offs + sizeof(Elf32_Nhdr) + + ALIGN(nhdr->n_namesz, 4) + ALIGN(nhdr->n_descsz, 4); + } + + return -ENOENT; +} + +/* Reads binary from *path* file and returns it in the *build_id* buffer + * with *size* which is expected to be at least BPF_BUILD_ID_SIZE bytes. + * Returns size of build id on success. On error the error value is + * returned. + */ +int read_build_id(const char *path, char *build_id, size_t size) +{ + int fd, err = -EINVAL; + Elf *elf = NULL; + GElf_Ehdr ehdr; + size_t max, i; + + if (size < BPF_BUILD_ID_SIZE) + return -EINVAL; + + fd = open(path, O_RDONLY | O_CLOEXEC); + if (fd < 0) + return -errno; + + (void)elf_version(EV_CURRENT); + + elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); + if (!elf) + goto out; + if (elf_kind(elf) != ELF_K_ELF) + goto out; + if (!gelf_getehdr(elf, &ehdr)) + goto out; + + for (i = 0; i < ehdr.e_phnum; i++) { + GElf_Phdr mem, *phdr; + char *data; + + phdr = gelf_getphdr(elf, i, &mem); + if (!phdr) + goto out; + if (phdr->p_type != PT_NOTE) + continue; + data = elf_rawfile(elf, &max); + if (!data) + goto out; + if (phdr->p_offset + phdr->p_memsz > max) + goto out; + err = parse_build_id_buf(data + phdr->p_offset, phdr->p_memsz, build_id); + if (err > 0) + break; + } + +out: + if (elf) + elf_end(elf); + close(fd); + return err; +} diff --git a/tools/testing/selftests/bpf/trace_helpers.h b/tools/testing/selftests/bpf/trace_helpers.h index 238a9c98cde27f..709871f3285256 100644 --- a/tools/testing/selftests/bpf/trace_helpers.h +++ b/tools/testing/selftests/bpf/trace_helpers.h @@ -4,6 +4,9 @@ #include +#define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask)) +#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1) + struct ksym { long addr; char *name; @@ -21,4 +24,6 @@ void read_trace_pipe(void); ssize_t get_uprobe_offset(const void *addr); ssize_t get_rel_offset(uintptr_t addr); +int read_build_id(const char *path, char *build_id, size_t size); + #endif -- 2.53.0