4.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Martin KaFai Lau <[email protected]> [ Upstream commit 4b1c5d917d34f705096bb7dd8a2bd19b0881970e ] The end boundary math for type section is incorrect in btf_check_all_metas(). It just happens that hdr->type_off is always 0 for now because there are only two sections (type and string) and string section must be at the end (ensured in btf_parse_str_sec). However, type_off may not be 0 if a new section would be added later. This patch fixes it. Fixes: f80442a4cd18 ("bpf: btf: Change how section is supported in btf_header") Reported-by: Dmitry Vyukov <[email protected]> Signed-off-by: Martin KaFai Lau <[email protected]> Acked-by: Yonghong Song <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/bpf/btf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -1844,7 +1844,7 @@ static int btf_check_all_metas(struct bt hdr = &btf->hdr; cur = btf->nohdr_data + hdr->type_off; - end = btf->nohdr_data + hdr->type_len; + end = cur + hdr->type_len; env->log_type_id = 1; while (cur < end) {
