From 8c9c67abda245c4abc46b7af8c0e102a116b0a5f Mon Sep 17 00:00:00 2001 From: Changqing Li Date: Thu, 10 Apr 2025 12:24:38 +0800 Subject: [PATCH] libbpf: fix a segmentation fault error 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. Signed-off-by: Changqing Li Signed-off-by: Khem Raj --- ...-empty-BTF-data-section-in-btf_parse.patch | 43 +++++++++++++++++++ meta-oe/recipes-kernel/libbpf/libbpf_1.5.0.bb | 4 +- 2 files changed, 46 insertions(+), 1 deletion(-) create mode 100644 meta-oe/recipes-kernel/libbpf/files/0001-libbpf-check-for-empty-BTF-data-section-in-btf_parse.patch diff --git a/meta-oe/recipes-kernel/libbpf/files/0001-libbpf-check-for-empty-BTF-data-section-in-btf_parse.patch b/meta-oe/recipes-kernel/libbpf/files/0001-libbpf-check-for-empty-BTF-data-section-in-btf_parse.patch new file mode 100644 index 0000000000..873995b644 --- /dev/null +++ b/meta-oe/recipes-kernel/libbpf/files/0001-libbpf-check-for-empty-BTF-data-section-in-btf_parse.patch @@ -0,0 +1,43 @@ +From ff2eb6e134ebfc225b97b46182af3cc58ed481f6 Mon Sep 17 00:00:00 2001 +From: Changqing Li +Date: Thu, 10 Apr 2025 11:50:04 +0800 +Subject: [PATCH] libbpf: check for empty BTF data section in btf_parse_elf + +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. + +Add a null check for a buffer returned by elf_getdata() before +proceeding with its processing. + +Bug report: https://github.com/libbpf/libbpf/issues/894 + +Signed-off-by: Ihor Solodrai +Acked-by: Mykyta Yatsenko + +Upstream-Status: Backport [https://github.com/kernel-patches/bpf-rc/commit/b02b669fd9398d246c8c9ae901c0d8f5bb36a588] + +Signed-off-by: Changqing Li +--- + btf.c | 6 ++++++ + 1 file changed, 6 insertions(+) + +diff --git a/btf.c b/btf.c +index e9673c0e..21d38dcf 100644 +--- a/btf.c ++++ b/btf.c +@@ -1199,6 +1199,12 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, + goto done; + } + ++ if (!secs.btf_data->d_buf) { ++ pr_warn("BTF data is empty in %s\n", path); ++ err = -ENODATA; ++ goto done; ++ } ++ + if (secs.btf_base_data) { + dist_base_btf = btf_new(secs.btf_base_data->d_buf, secs.btf_base_data->d_size, + NULL); +-- +2.34.1 + diff --git a/meta-oe/recipes-kernel/libbpf/libbpf_1.5.0.bb b/meta-oe/recipes-kernel/libbpf/libbpf_1.5.0.bb index 5f92939274..58bb7bca09 100644 --- a/meta-oe/recipes-kernel/libbpf/libbpf_1.5.0.bb +++ b/meta-oe/recipes-kernel/libbpf/libbpf_1.5.0.bb @@ -8,7 +8,9 @@ LIC_FILES_CHKSUM = "file://../LICENSE.LGPL-2.1;md5=b370887980db5dd40659b50909238 DEPENDS = "zlib elfutils" -SRC_URI = "git://github.com/libbpf/libbpf.git;protocol=https;branch=master" +SRC_URI = "git://github.com/libbpf/libbpf.git;protocol=https;branch=master \ + file://0001-libbpf-check-for-empty-BTF-data-section-in-btf_parse.patch \ +" SRCREV = "09b9e83102eb8ab9e540d36b4559c55f3bcdb95d" PACKAGE_ARCH = "${MACHINE_ARCH}"