diff options
| author | Andrii Nakryiko <andrii@kernel.org> | 2021-10-22 17:31:56 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-10-22 17:33:31 -0700 |
| commit | 5245dafe3d49efba4d3285cf27ee1cc1eeafafc6 (patch) | |
| tree | 62ded1edf9df0e669f175a35d0a8f3633f82d11b /tools/lib | |
| parent | 1c508843700423f36bead47a78169f313f5668f5 (diff) | |
libbpf: Fix overflow in BTF sanity checks
btf_header's str_off+str_len or type_off+type_len can overflow as they
are u32s. This will lead to bypassing the sanity checks during BTF
parsing, resulting in crashes afterwards. Fix by using 64-bit signed
integers for comparison.
Fixes: d8123624506c ("libbpf: Fix BTF data layout checks and allow empty BTF")
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/20211023003157.726961-1-andrii@kernel.org
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/btf.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 66997d985ff8..05b945208815 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -241,12 +241,12 @@ static int btf_parse_hdr(struct btf *btf) } meta_left = btf->raw_size - sizeof(*hdr); - if (meta_left < hdr->str_off + hdr->str_len) { + if (meta_left < (long long)hdr->str_off + hdr->str_len) { pr_debug("Invalid BTF total size:%u\n", btf->raw_size); return -EINVAL; } - if (hdr->type_off + hdr->type_len > hdr->str_off) { + if ((long long)hdr->type_off + hdr->type_len > hdr->str_off) { pr_debug("Invalid BTF data sections layout: type data at %u + %u, strings data at %u + %u\n", hdr->type_off, hdr->type_len, hdr->str_off, hdr->str_len); return -EINVAL; |