packet: validate msg_namelen in send directly

[ Upstream commit 486efdc8f6ce802b27e15921d2353cc740c55451 ]

Packet sockets in datagram mode take a destination address. Verify its
length before passing to dev_hard_header.

Prior to 2.6.14-rc3, the send code ignored sll_halen. This is
established behavior. Directly compare msg_namelen to dev->addr_len.

Change v1->v2: initialize addr in all paths

Fixes: 6b8d95f1795c4 ("packet: validate address length if non-zero")
Suggested-by: David Laight <David.Laight@aculab.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Willem de Bruijn 2019-04-29 11:53:18 -04:00 committed by syphyr
parent c9085fc103
commit 83f29caf4b
1 changed files with 14 additions and 9 deletions

View File

@ -2103,8 +2103,8 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
int err, reserve = 0;
void *ph;
struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
unsigned char *addr = NULL;
int tp_len, size_max;
unsigned char *addr;
int len_sum = 0;
int status = TP_STATUS_AVAILABLE;
int hlen, tlen;
@ -2124,10 +2124,13 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
sll_addr)))
goto out;
proto = saddr->sll_protocol;
addr = saddr->sll_halen ? saddr->sll_addr : NULL;
dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
if (addr && dev && saddr->sll_halen < dev->addr_len)
goto out_put;
if (po->sk.sk_socket->type == SOCK_DGRAM) {
if (dev && msg->msg_namelen < dev->addr_len +
offsetof(struct sockaddr_ll, sll_addr))
goto out_put;
addr = saddr->sll_addr;
}
}
err = -ENXIO;
@ -2253,7 +2256,7 @@ static int packet_snd(struct socket *sock,
struct sk_buff *skb;
struct net_device *dev;
__be16 proto;
unsigned char *addr;
unsigned char *addr = NULL;
int err, reserve = 0;
struct virtio_net_hdr vnet_hdr = { 0 };
int offset = 0;
@ -2271,7 +2274,6 @@ static int packet_snd(struct socket *sock,
if (likely(saddr == NULL)) {
dev = packet_cached_dev_get(po);
proto = po->num;
addr = NULL;
} else {
err = -EINVAL;
if (msg->msg_namelen < sizeof(struct sockaddr_ll))
@ -2279,10 +2281,13 @@ static int packet_snd(struct socket *sock,
if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
goto out;
proto = saddr->sll_protocol;
addr = saddr->sll_halen ? saddr->sll_addr : NULL;
dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
if (addr && dev && saddr->sll_halen < dev->addr_len)
goto out_unlock;
if (sock->type == SOCK_DGRAM) {
if (dev && msg->msg_namelen < dev->addr_len +
offsetof(struct sockaddr_ll, sll_addr))
goto out_unlock;
addr = saddr->sll_addr;
}
}
err = -ENXIO;