diff options
| author | Craig Gallek <kraig@google.com> | 2016-01-19 14:27:08 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-01-19 14:44:23 -0500 |
| commit | b4ace4f1ae07691b4f6ea9f3e92efbec083df058 (patch) | |
| tree | 6845c5f7ff2e8994046ac9a41ea5d5ec00fd21ab | |
| parent | 52a82e23b9f2a9e1d429c5207f8575784290d008 (diff) | |
| download | linux-b4ace4f1ae07691b4f6ea9f3e92efbec083df058.tar.bz2 | |
soreuseport: fix NULL ptr dereference SO_REUSEPORT after bind
Marc Dionne discovered a NULL pointer dereference when setting
SO_REUSEPORT on a socket after it is bound.
This patch removes the assumption that at least one socket in the
reuseport group is bound with the SO_REUSEPORT option before other
bind calls occur.
Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection")
Reported-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: Craig Gallek <kraig@google.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/sock_reuseport.h | 2 | ||||
| -rw-r--r-- | net/core/sock_reuseport.c | 9 |
2 files changed, 9 insertions, 2 deletions
diff --git a/include/net/sock_reuseport.h b/include/net/sock_reuseport.h index 7dda3d7adba8..aecd30308d50 100644 --- a/include/net/sock_reuseport.h +++ b/include/net/sock_reuseport.h @@ -16,7 +16,7 @@ struct sock_reuseport { }; extern int reuseport_alloc(struct sock *sk); -extern int reuseport_add_sock(struct sock *sk, const struct sock *sk2); +extern int reuseport_add_sock(struct sock *sk, struct sock *sk2); extern void reuseport_detach_sock(struct sock *sk); extern struct sock *reuseport_select_sock(struct sock *sk, u32 hash, diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c index 1df98c557440..e92b759d906c 100644 --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -93,10 +93,17 @@ static struct sock_reuseport *reuseport_grow(struct sock_reuseport *reuse) * @sk2: Socket belonging to the existing reuseport group. * May return ENOMEM and not add socket to group under memory pressure. */ -int reuseport_add_sock(struct sock *sk, const struct sock *sk2) +int reuseport_add_sock(struct sock *sk, struct sock *sk2) { struct sock_reuseport *reuse; + if (!rcu_access_pointer(sk2->sk_reuseport_cb)) { + int err = reuseport_alloc(sk2); + + if (err) + return err; + } + spin_lock_bh(&reuseport_lock); reuse = rcu_dereference_protected(sk2->sk_reuseport_cb, lockdep_is_held(&reuseport_lock)), |