2022-08-30 07:59:10

by Haimin Zhang

[permalink] [raw]
Subject: [PATCH V2] net/ieee802154: fix uninit value bug in dgram_sendmsg

There is uninit value bug in dgram_sendmsg function in
net/ieee802154/socket.c when the length of valid data pointed by the
msg->msg_name isn't verified.

We should check the msg_namelen is not less than struct
sockaddr_ieee802154 when addr_type is SHORT before calling
ieee802154_addr_from_sa. So we define IEEE802154_MIN_NAMELEN.
And in function ieee802154_addr_from_sa, when
addr_type is LONG, we check msg_namelen is not less than
sizeof(struct sockaddr_ieee802154). Meanwhile we check in the
beginning of function dgram_sendmsg.

Also fixed in raw_bind, dgram_bind, dgram_connect.

Signed-off-by: Haimin Zhang <[email protected]>
---
include/net/ieee802154_netdev.h | 9 ++++--
net/ieee802154/socket.c | 52 ++++++++++++++++++++-------------
2 files changed, 39 insertions(+), 22 deletions(-)

diff --git a/include/net/ieee802154_netdev.h b/include/net/ieee802154_netdev.h
index d0d188c32..e1dc3fb02 100644
--- a/include/net/ieee802154_netdev.h
+++ b/include/net/ieee802154_netdev.h
@@ -165,8 +165,8 @@ static inline void ieee802154_devaddr_to_raw(void *raw, __le64 addr)
memcpy(raw, &temp, IEEE802154_ADDR_LEN);
}

-static inline void ieee802154_addr_from_sa(struct ieee802154_addr *a,
- const struct ieee802154_addr_sa *sa)
+static inline int ieee802154_addr_from_sa(struct ieee802154_addr *a,
+ const struct ieee802154_addr_sa *sa, int len)
{
a->mode = sa->addr_type;
a->pan_id = cpu_to_le16(sa->pan_id);
@@ -176,9 +176,14 @@ static inline void ieee802154_addr_from_sa(struct ieee802154_addr *a,
a->short_addr = cpu_to_le16(sa->short_addr);
break;
case IEEE802154_ADDR_LONG:
+ if (len > sizeof(struct sockaddr_ieee802154))
+ return -EINVAL;
a->extended_addr = ieee802154_devaddr_from_raw(sa->hwaddr);
break;
+ default:
+ return -EINVAL;
}
+ return 0;
}

static inline void ieee802154_addr_to_sa(struct ieee802154_addr_sa *sa,
diff --git a/net/ieee802154/socket.c b/net/ieee802154/socket.c
index 718fb77bb..4452aaf68 100644
--- a/net/ieee802154/socket.c
+++ b/net/ieee802154/socket.c
@@ -27,6 +27,10 @@
#include <net/af_ieee802154.h>
#include <net/ieee802154_netdev.h>

+#define IEEE802154_MIN_NAMELEN \
+ (offsetof(struct sockaddr_ieee802154, addr) + \
+ offsetofend(struct ieee802154_addr_sa, short_addr))
+
/* Utility function for families */
static struct net_device*
ieee802154_get_dev(struct net *net, const struct ieee802154_addr *addr)
@@ -200,7 +204,7 @@ static int raw_bind(struct sock *sk, struct sockaddr *_uaddr, int len)
int err = 0;
struct net_device *dev = NULL;

- if (len < sizeof(*uaddr))
+ if (len < IEEE802154_MIN_NAMELEN)
return -EINVAL;

uaddr = (struct sockaddr_ieee802154 *)_uaddr;
@@ -209,7 +213,9 @@ static int raw_bind(struct sock *sk, struct sockaddr *_uaddr, int len)

lock_sock(sk);

- ieee802154_addr_from_sa(&addr, &uaddr->addr);
+ err = ieee802154_addr_from_sa(&addr, &uaddr->addr, len);
+ if (err < 0)
+ goto out;
dev = ieee802154_get_dev(sock_net(sk), &addr);
if (!dev) {
err = -ENODEV;
@@ -493,13 +499,15 @@ static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)

ro->bound = 0;

- if (len < sizeof(*addr))
+ if (len < IEEE802154_MIN_NAMELEN)
goto out;

if (addr->family != AF_IEEE802154)
goto out;

- ieee802154_addr_from_sa(&haddr, &addr->addr);
+ err = ieee802154_addr_from_sa(&haddr, &addr->addr, len);
+ if (err < 0)
+ goto out;
dev = ieee802154_get_dev(sock_net(sk), &haddr);
if (!dev) {
err = -ENODEV;
@@ -564,7 +572,7 @@ static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
struct dgram_sock *ro = dgram_sk(sk);
int err = 0;

- if (len < sizeof(*addr))
+ if (len < IEEE802154_MIN_NAMELEN)
return -EINVAL;

if (addr->family != AF_IEEE802154)
@@ -577,7 +585,9 @@ static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
goto out;
}

- ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
+ err = ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr, len);
+ if (err < 0)
+ goto out;
ro->connected = 1;

out:
@@ -612,10 +622,22 @@ static int dgram_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
return -EOPNOTSUPP;
}

- if (!ro->connected && !msg->msg_name)
- return -EDESTADDRREQ;
- else if (ro->connected && msg->msg_name)
- return -EISCONN;
+ if (msg->msg_name) {
+ if (ro->connected)
+ return -EISCONN;
+ if (msg->msg_namelen < IEEE802154_MIN_NAMELEN)
+ return -EINVAL;
+ DECLARE_SOCKADDR(struct sockaddr_ieee802154*,
+ daddr, msg->msg_name);
+ err = ieee802154_addr_from_sa(&dst_addr, &daddr->addr,
+ msg->msg_namelen);
+ if (err < 0)
+ return err;
+ } else {
+ if (!ro->connected)
+ return -EDESTADDRREQ;
+ dst_addr = ro->dst_addr;
+ }

if (!ro->bound)
dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
@@ -651,16 +673,6 @@ static int dgram_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
cb = mac_cb_init(skb);
cb->type = IEEE802154_FC_TYPE_DATA;
cb->ackreq = ro->want_ack;
-
- if (msg->msg_name) {
- DECLARE_SOCKADDR(struct sockaddr_ieee802154*,
- daddr, msg->msg_name);
-
- ieee802154_addr_from_sa(&dst_addr, &daddr->addr);
- } else {
- dst_addr = ro->dst_addr;
- }
-
cb->secen = ro->secen;
cb->secen_override = ro->secen_override;
cb->seclevel = ro->seclevel;
--
2.27.0


2022-09-08 02:27:40

by Alexander Aring

[permalink] [raw]
Subject: Re: [PATCH V2] net/ieee802154: fix uninit value bug in dgram_sendmsg

Hi,

On Tue, Aug 30, 2022 at 3:03 AM Haimin Zhang <[email protected]> wrote:
>
> There is uninit value bug in dgram_sendmsg function in
> net/ieee802154/socket.c when the length of valid data pointed by the
> msg->msg_name isn't verified.
>
> We should check the msg_namelen is not less than struct
> sockaddr_ieee802154 when addr_type is SHORT before calling
> ieee802154_addr_from_sa. So we define IEEE802154_MIN_NAMELEN.
> And in function ieee802154_addr_from_sa, when
> addr_type is LONG, we check msg_namelen is not less than
> sizeof(struct sockaddr_ieee802154). Meanwhile we check in the
> beginning of function dgram_sendmsg.
>

There exists also an IEEE802154_ADDR_NONE addr_type.

We need to first check that space is there to evaluate the addr_type.

If it's NONE, ignore hwaddr or short address. If it's SHORT or hwaddr
check if they have space for it, if it's something completely
different return -EINVAL.

There are still missing bits and I would recommend introducing a
helper function to do this "kind" of more complex check. This patch
spreads different checks around by checking on IEEE802154_MIN_NAMELEN
(which isn't correct, because NONE) and then requires another check by
calling ieee802154_addr_from_sa() and checking the return code.

- Alex