mirror/libbpf
1
0 Fork 0
mirror of https://github.com/netdata/libbpf.git synced 2026-11-06 09:50:15 +08:00
Code Issues Packages Projects Releases Wiki Activity

libbpf: Fix BTF data layout checks and allow empty BTF

Browse Source 
Make data section layout checks stricter, disallowing overlap of types and
strings data.

Additionally, allow BTFs with no type data. There is nothing inherently wrong
with having BTF with no types (put potentially with some strings). This could
be a situation with kernel module BTFs, if module doesn't introduce any new
type information.

Also fix invalid offset alignment check for btf->hdr->type_off.

Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-8-andrii@kernel.org
This commit is contained in:
Andrii Nakryiko authored and Andrii Nakryiko committed 2020-11-05 21:20:45 -08:00
1 parent 2811d54f8b
commit dd36215834
1 file changed
+6 -10
Download Patch File Download Diff File Expand all files Collapse all files
src/btf.c
+6 -10
View File
@@ -245,22 +245,18 @@ static int btf_parse_hdr(struct btf *btf)
return -EINVAL;
}
if (meta_left < hdr->type_off) {
pr_debug("Invalid BTF type section offset:%u\n", hdr->type_off);
if (meta_left < hdr->str_off + hdr->str_len) {
pr_debug("Invalid BTF total size:%u\n", btf->raw_size);
return -EINVAL;
}
if (meta_left < hdr->str_off) {
pr_debug("Invalid BTF string section offset:%u\n", hdr->str_off);
if (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;
}
if (hdr->type_off >= hdr->str_off) {
pr_debug("BTF type section offset >= string section offset. No type?\n");
return -EINVAL;
}
if (hdr->type_off & 0x02) {
if (hdr->type_off % 4) {
pr_debug("BTF type section is not aligned to 4 bytes\n");
return -EINVAL;
}