diff options
| author | Eugenio Pérez <eperezma@redhat.com> | 2020-03-05 17:30:05 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-02 19:02:34 +0200 |
| commit | 79152052fbb703ff5f66778b3e585c69b95d83d2 (patch) | |
| tree | f9ada3a6dc51035ddf21d2299380c6a4f1167eda | |
| parent | 5f64b16c47aa4c9ed60671a6eb1c92c433d1b19a (diff) | |
vhost: Check docket sk_family instead of call getname
[ Upstream commit 42d84c8490f9f0931786f1623191fcab397c3d64 ]
Doing so, we save one call to get data we already have in the struct.
Also, since there is no guarantee that getname use sockaddr_ll
parameter beyond its size, we add a little bit of security here.
It should do not do beyond MAX_ADDR_LEN, but syzbot found that
ax25_getname writes more (72 bytes, the size of full_sockaddr_ax25,
versus 20 + 32 bytes of sockaddr_ll + MAX_ADDR_LEN in syzbot repro).
Fixes: 3a4d5c94e9593 ("vhost_net: a kernel-level virtio server")
Reported-by: syzbot+f2a62d07a5198c819c7b@syzkaller.appspotmail.com
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/vhost/net.c | 13 |
1 files changed, 2 insertions, 11 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 1459dc9fd701..5efac33c29dc 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -815,11 +815,7 @@ static int vhost_net_release(struct inode *inode, struct file *f) static struct socket *get_raw_socket(int fd) { - struct { - struct sockaddr_ll sa; - char buf[MAX_ADDR_LEN]; - } uaddr; - int uaddr_len = sizeof uaddr, r; + int r; struct socket *sock = sockfd_lookup(fd, &r); if (!sock) @@ -831,12 +827,7 @@ static struct socket *get_raw_socket(int fd) goto err; } - r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, - &uaddr_len, 0); - if (r) - goto err; - - if (uaddr.sa.sll_family != AF_PACKET) { + if (sock->sk->sk_family != AF_PACKET) { r = -EPFNOSUPPORT; goto err; } |