From cabb9ce91456d4dbfe466b2caf8e417b1bd31982 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 24 Aug 2022 11:24:56 +0800 Subject: [PATCH] libbpf: Detect corrupted ELF symbols section mainline inclusion from mainline-5.17-rc1 commit 833907876be55205d0ec153dcd819c014404ee16 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=833907876be55205d0ec153dcd819c014404ee16 ------------------------------------------------- Prevent divide-by-zero if ELF is corrupted and has zero sh_entsize. Reported by oss-fuzz project. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20211103173213.1376990-2-andrii@kernel.org (cherry picked from commit 833907876be55205d0ec153dcd819c014404ee16) Signed-off-by: Wang Yufen --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b9f0559c52db..7997075b1ae0 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3513,7 +3513,7 @@ static int bpf_object__collect_externs(struct bpf_object *obj) scn = elf_sec_by_idx(obj, obj->efile.symbols_shndx); sh = elf_sec_hdr(obj, scn); - if (!sh) + if (!sh || sh->sh_entsize != sizeof(Elf64_Sym)) return -LIBBPF_ERRNO__FORMAT; dummy_var_btf_id = add_dummy_ksym_var(obj->btf); -- GitLab