On 11/30/23 3:53 PM, Eric Dumazet wrote:
On Thu, Nov 30, 2023 at 12:49 AM Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote:
Hi David, hi Jakub, hi Paolo, hi Eric,
The following pull-request contains BPF updates for your *net* tree.
We've added 5 non-merge commits during the last 7 day(s) which contain
a total of 10 files changed, 66 insertions(+), 15 deletions(-).
The main changes are:
1) Fix AF_UNIX splat from use after free in BPF sockmap, from John Fastabend.
syzbot is not happy with this patch.
Would the following fix make sense?
diff --git a/net/unix/unix_bpf.c b/net/unix/unix_bpf.c
index 7ea7c3a0d0d06224f49ad5f073bf772b9528a30a..58e89361059fbf9d5942c6dd268dd80ac4b57098
100644
--- a/net/unix/unix_bpf.c
+++ b/net/unix/unix_bpf.c
@@ -168,7 +168,8 @@ int unix_stream_bpf_update_proto(struct sock *sk,
struct sk_psock *psock, bool r
}
sk_pair = unix_peer(sk);
- sock_hold(sk_pair);
+ if (sk_pair)
+ sock_hold(sk_pair);
psock->sk_pair = sk_pair;
unix_stream_bpf_check_needs_rebuild(psock->sk_proto);
sock_replace_proto(sk, &unix_stream_bpf_prot);
Oh well :/ Above looks reasonable to me, thanks, but I'll defer to John & Jakub (both Cc'ed)
for a final look.
Thanks,
Daniel
