netdev - [PATCH net-next 02/16] net/compat: Fix minor information leak in siocdevprivate

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 5 Dec 2013 23:42:02 +0000
From:	Ben Hutchings <bhutchings@...arflare.com>
To:	David Miller <davem@...emloft.net>
CC:	<netdev@...r.kernel.org>, <linux-net-drivers@...arflare.com>,
	"Richard Cochran" <richardcochran@...il.com>
Subject: [PATCH net-next 02/16] net/compat: Fix minor information leak in
 siocdevprivate_ioctl()

We don't need to check that ifr_data itself is a valid user pointer,
but we should check &ifr_data is.  Thankfully the copy of ifr_name is
checked, so this can only leak a few bytes from immediately above the
user address limit.

Signed-off-by: Ben Hutchings <bhutchings@...arflare.com>
---
This might deserve to go into net instead.  Not sure.

Ben.

 net/socket.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index c226aceee65b..fbb6ec13b1f4 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -3015,19 +3015,16 @@ static int siocdevprivate_ioctl(struct net *net, unsigned int cmd,
 	if (copy_from_user(&tmp_buf[0], &(u_ifreq32->ifr_ifrn.ifrn_name[0]),
 			   IFNAMSIZ))
 		return -EFAULT;
-	if (__get_user(data32, &u_ifreq32->ifr_ifru.ifru_data))
+	if (get_user(data32, &u_ifreq32->ifr_ifru.ifru_data))
 		return -EFAULT;
 	data64 = compat_ptr(data32);
 
 	u_ifreq64 = compat_alloc_user_space(sizeof(*u_ifreq64));
 
-	/* Don't check these user accesses, just let that get trapped
-	 * in the ioctl handler instead.
-	 */
 	if (copy_to_user(&u_ifreq64->ifr_ifrn.ifrn_name[0], &tmp_buf[0],
 			 IFNAMSIZ))
 		return -EFAULT;
-	if (__put_user(data64, &u_ifreq64->ifr_ifru.ifru_data))
+	if (put_user(data64, &u_ifreq64->ifr_ifru.ifru_data))
 		return -EFAULT;
 
 	return dev_ioctl(net, cmd, u_ifreq64);


-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html