| Message ID | 20180124072529.1197737-5-brakmo@fb.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf-next,v7,01/12] bpf: Make SOCK_OPS_GET_TCP size independent | expand |
diff --git a/net/core/filter.c b/net/core/filter.c index 0cf170f..c356ec0 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3845,8 +3845,7 @@ static bool sock_ops_is_valid_access(int off, int size, { if (type == BPF_WRITE) { switch (off) { - case offsetof(struct bpf_sock_ops, op) ... - offsetof(struct bpf_sock_ops, replylong[3]): + case offsetof(struct bpf_sock_ops, reply): break; default: return false;
Currently, a sock_ops BPF program can write the op field and all the reply fields (reply and replylong). This is a bug. The op field should not have been writeable and there is currently no way to use replylong field for indices >= 1. This patch enforces that only the reply field (which equals replylong[0]) is writeable. Fixes: 40304b2a1567 ("bpf: BPF support for sock_ops") Signed-off-by: Lawrence Brakmo <brakmo@fb.com> --- net/core/filter.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)