This if guards whether user-space wants a copy of the offload-jited
bytecode and whether this bytecode exists. By erroneously doing a bitwise
AND instead of a logical AND on user- and kernel-space buffer-size can lead
to no data being copied to user-space especially when user-space size is a
power of two and bigger then the kernel-space buffer.
Signed-off-by: Johannes Krude <johannes@xxxxxxxx>
---
kernel/bpf/offload.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c
index 2c5dc6541..bd09290e3 100644
--- a/kernel/bpf/offload.c
+++ b/kernel/bpf/offload.c
@@ -321,7 +321,7 @@ int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
ulen = info->jited_prog_len;
info->jited_prog_len = aux->offload->jited_len;
- if (info->jited_prog_len & ulen) {
+ if (info->jited_prog_len && ulen) {
uinsns = u64_to_user_ptr(info->jited_prog_insns);
ulen = min_t(u32, info->jited_prog_len, ulen);
if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) {
--
2.24.0
