From: Andrii Nakryiko <andrii@kernel.org>
Date: Wed, 3 Nov 2021 10:32:09 -0700
Subject: libbpf: Detect corrupted ELF symbols section
Patch-mainline: v5.17-rc1
Git-commit: 833907876be55205d0ec153dcd819c014404ee16
References: jsc#PED-1377
Prevent divide-by-zero if ELF is corrupted and has zero sh_entsize.
Reported by oss-fuzz project.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211103173213.1376990-2-andrii@kernel.org
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
tools/lib/bpf/libbpf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3555,7 +3555,7 @@ static int bpf_object__collect_externs(s
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);