lkml.org 
[lkml]   [2022]   [Jan]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 5.10 003/116] libbpf: Validate that .BTF and .BTF.ext sections contain data
Date
From: Andrii Nakryiko <andrii@kernel.org>

[ Upstream commit 62554d52e71797eefa3fc15b54008038837bb2d4 ]

.BTF and .BTF.ext ELF sections should have SHT_PROGBITS type and contain
data. If they are not, ELF is invalid or corrupted, so bail out.
Otherwise this can lead to data->d_buf being NULL and SIGSEGV later on.
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/20211103173213.1376990-4-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/lib/bpf/libbpf.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index b337d6f29098b..e8ad53d31044a 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2870,8 +2870,12 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
} else if (strcmp(name, MAPS_ELF_SEC) == 0) {
obj->efile.btf_maps_shndx = idx;
} else if (strcmp(name, BTF_ELF_SEC) == 0) {
+ if (sh->sh_type != SHT_PROGBITS)
+ return -LIBBPF_ERRNO__FORMAT;
btf_data = data;
} else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) {
+ if (sh->sh_type != SHT_PROGBITS)
+ return -LIBBPF_ERRNO__FORMAT;
btf_ext_data = data;
} else if (sh.sh_type == SHT_SYMTAB) {
/* already processed during the first pass above */
--
2.34.1
\
 
 \ /
  Last update: 2022-01-18 04:10    [W:1.893 / U:0.368 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site