This is a note to let you know that I've just added the patch titled
libbpf: Validate that .BTF and .BTF.ext sections contain data
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
libbpf-validate-that-.btf-and-.btf.ext-sections-cont.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 91230f9cc6744934c144a549c16afe63a5c87ff1
Author: Andrii Nakryiko <andrii@xxxxxxxxxx>
Date: Wed Nov 3 10:32:11 2021 -0700
libbpf: Validate that .BTF and .BTF.ext sections contain data
[ 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@xxxxxxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Acked-by: Yonghong Song <yhs@xxxxxx>
Link: https://lore.kernel.org/bpf/20211103173213.1376990-4-andrii@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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 */
