iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

libbpf: Fix BTF header parsing checks

Browse Source 
[ Upstream commit c825f5fee19caf301d9821cd79abaa734322de26 ]

Original code assumed fixed and correct BTF header length. That's not
always the case, though, so fix this bug with a proper additional check.
And use actual header length instead of sizeof(struct btf_header) in
sanity checks.

Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf")
Reported-by: Evgeny Vereshchagin <evvers@ya.ru>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211023003157.726961-2-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Andrii Nakryiko 2021-10-22 17:31:57 -07:00 committed by Greg Kroah-Hartman
parent ffb5d239e7
commit ae2df72314
1 changed files with 9 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
tools/lib/bpf/btf.c
View File

@ -231,13 +231,19 @@ static int btf_parse_hdr(struct btf *btf)
}
btf_bswap_hdr(hdr);
} else if (hdr->magic != BTF_MAGIC) {
pr_debug("Invalid BTF magic:%x\n", hdr->magic);
pr_debug("Invalid BTF magic: %x\n", hdr->magic);
return -EINVAL;
}
meta_left = btf->raw_size - sizeof(*hdr);
if (btf->raw_size < hdr->hdr_len) {
pr_debug("BTF header len %u larger than data size %u\n",
hdr->hdr_len, btf->raw_size);
return -EINVAL;
}
meta_left = btf->raw_size - hdr->hdr_len;
if (meta_left < (long long)hdr->str_off + hdr->str_len) {
pr_debug("Invalid BTF total size:%u\n", btf->raw_size);
pr_debug("Invalid BTF total size: %u\n", btf->raw_size);
return -EINVAL;
}