| Message ID | 1289413760-12510-1-git-send-email-segooon@gmail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Vasiliy Kulikov <segooon@gmail.com> Date: Wed, 10 Nov 2010 21:29:18 +0300 > packet_getname_spkt() doesn't initialize all members of sa_data field of > sockaddr struct if strlen(dev->name) < 13. This structure is then copied > to userland. It leads to leaking of contents of kernel stack memory. > We have to fully fill sa_data with strncpy() instead of strlcpy(). > > The same with packet_getname(): it doesn't initialize sll_pkttype field of > sockaddr_ll. Set it to zero. > > Signed-off-by: Vasiliy Kulikov <segooon@gmail.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 3616f27..0856a13 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1719,7 +1719,7 @@ static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); if (dev) - strlcpy(uaddr->sa_data, dev->name, 15); + strncpy(uaddr->sa_data, dev->name, 14); else memset(uaddr->sa_data, 0, 14); rcu_read_unlock(); @@ -1742,6 +1742,7 @@ static int packet_getname(struct socket *sock, struct sockaddr *uaddr, sll->sll_family = AF_PACKET; sll->sll_ifindex = po->ifindex; sll->sll_protocol = po->num; + sll->sll_pkttype = 0; rcu_read_lock(); dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); if (dev) {
packet_getname_spkt() doesn't initialize all members of sa_data field of sockaddr struct if strlen(dev->name) < 13. This structure is then copied to userland. It leads to leaking of contents of kernel stack memory. We have to fully fill sa_data with strncpy() instead of strlcpy(). The same with packet_getname(): it doesn't initialize sll_pkttype field of sockaddr_ll. Set it to zero. Signed-off-by: Vasiliy Kulikov <segooon@gmail.com> --- Compile tested. net/packet/af_packet.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)