Bluetooth: bnep: fix buffer overflow

Struct ca is copied from userspace.  It is not checked whether the "device"
field is NULL terminated.  This potentially leads to BUG() inside of
alloc_netdev_mqs() and/or information leak by creating a device with a name
made of contents of kernel stack.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

1 files changed, 1 insertions, 0 deletions

diff --git a/net/bluetooth/bnep/sock.c b/net/bluetooth/bnep/sock.c
index 2862f53b66b1..d935da71ab3b 100644
--- a/net/bluetooth/bnep/sock.c
+++ b/net/bluetooth/bnep/sock.c
@@ -88,6 +88,7 @@ static int bnep_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long
                         sockfd_put(nsock);
                         return -EBADFD;
                 }
+                ca.device[sizeof(ca.device)-1] = 0;
 
                 err = bnep_add_connection(&ca, nsock);
                 if (!err) {