From a9b3cd7f323b2e57593e7215362a7b02fc933e3a Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Mon, 1 Aug 2011 16:19:00 +0000 Subject: rcu: convert uses of rcu_assign_pointer(x, NULL) to RCU_INIT_POINTER When assigning a NULL value to an RCU protected pointer, no barrier is needed. The rcu_assign_pointer, used to handle that but will soon change to not handle the special case. Convert all rcu_assign_pointer of NULL value. //smpl @@ expression P; @@ - rcu_assign_pointer(P, NULL) + RCU_INIT_POINTER(P, NULL) // Signed-off-by: Stephen Hemminger Acked-by: Paul E. McKenney Signed-off-by: David S. Miller --- net/socket.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/socket.c') diff --git a/net/socket.c b/net/socket.c index b1cbbcd92558..7ec8f9b669b3 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2463,7 +2463,7 @@ int sock_register(const struct net_proto_family *ops) lockdep_is_held(&net_family_lock))) err = -EEXIST; else { - rcu_assign_pointer(net_families[ops->family], ops); + RCU_INIT_POINTER(net_families[ops->family], ops); err = 0; } spin_unlock(&net_family_lock); @@ -2491,7 +2491,7 @@ void sock_unregister(int family) BUG_ON(family < 0 || family >= NPROTO); spin_lock(&net_family_lock); - rcu_assign_pointer(net_families[family], NULL); + RCU_INIT_POINTER(net_families[family], NULL); spin_unlock(&net_family_lock); synchronize_rcu(); -- cgit v1.2.3 From bc909d9ddbf7778371e36a651d6e4194b1cc7d4c Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Wed, 24 Aug 2011 19:45:03 -0700 Subject: sendmmsg/sendmsg: fix unsafe user pointer access Dereferencing a user pointer directly from kernel-space without going through the copy_from_user family of functions is a bad idea. Two of such usages can be found in the sendmsg code path called from sendmmsg, added by commit c71d8ebe7a4496fb7231151cb70a6baa0cb56f9a upstream. commit 5b47b8038f183b44d2d8ff1c7d11a5c1be706b34 in the 3.0-stable tree. Usages are performed through memcmp() and memcpy() directly. Fix those by using the already copied msg_sys structure instead of the __user *msg structure. Note that msg_sys can be set to NULL by verify_compat_iovec() or verify_iovec(), which requires additional NULL pointer checks. Signed-off-by: Mathieu Desnoyers Signed-off-by: David Goulet CC: Tetsuo Handa CC: Anton Blanchard CC: David S. Miller CC: stable Signed-off-by: David S. Miller --- net/socket.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'net/socket.c') diff --git a/net/socket.c b/net/socket.c index 24a77400b65e..ffe92ca32f2a 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1965,8 +1965,9 @@ static int __sys_sendmsg(struct socket *sock, struct msghdr __user *msg, * used_address->name_len is initialized to UINT_MAX so that the first * destination address never matches. */ - if (used_address && used_address->name_len == msg_sys->msg_namelen && - !memcmp(&used_address->name, msg->msg_name, + if (used_address && msg_sys->msg_name && + used_address->name_len == msg_sys->msg_namelen && + !memcmp(&used_address->name, msg_sys->msg_name, used_address->name_len)) { err = sock_sendmsg_nosec(sock, msg_sys, total_len); goto out_freectl; @@ -1978,8 +1979,9 @@ static int __sys_sendmsg(struct socket *sock, struct msghdr __user *msg, */ if (used_address && err >= 0) { used_address->name_len = msg_sys->msg_namelen; - memcpy(&used_address->name, msg->msg_name, - used_address->name_len); + if (msg_sys->msg_name) + memcpy(&used_address->name, msg_sys->msg_name, + used_address->name_len); } out_freectl: -- cgit v1.2.3