From: Mathias Krause <[email protected]> ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. -------------------
commit 4683f42fde3977bdb4e8a09622788cc8b5313778 upstream. In case the socket is already shutting down, bt_sock_recvmsg() returns with 0 without updating msg_namelen leading to net/socket.c leaking the local, uninitialized sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. Fix this by moving the msg_namelen assignment in front of the shutdown test. Cc: Marcel Holtmann <[email protected]> Cc: Gustavo Padovan <[email protected]> Cc: Johan Hedberg <[email protected]> Signed-off-by: Mathias Krause <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Paul Gortmaker <[email protected]> --- net/bluetooth/af_bluetooth.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index 404a8500fd03..0891857b7ca2 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -240,14 +240,14 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock, if (flags & (MSG_OOB)) return -EOPNOTSUPP; + msg->msg_namelen = 0; + if (!(skb = skb_recv_datagram(sk, flags, noblock, &err))) { if (sk->sk_shutdown & RCV_SHUTDOWN) return 0; return err; } - msg->msg_namelen = 0; - copied = skb->len; if (len < copied) { msg->msg_flags |= MSG_TRUNC; -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
