4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Willy Tarreau <w@xxxxxx> [ Upstream commit 9824dfae5741275473a23a7ed5756c7b6efacc9d ] Fields ->dev and ->next of struct ipddp_route may be copied to userspace on the SIOCFINDIPDDPRT ioctl. This is only accessible to CAP_NET_ADMIN though. Let's manually copy the relevant fields instead of using memcpy(). BugLink: http://blog.infosectcbr.com.au/2018/09/linux-kernel-infoleaks.html Cc: Jann Horn <jannh@xxxxxxxxxx> Signed-off-by: Willy Tarreau <w@xxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/appletalk/ipddp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/net/appletalk/ipddp.c +++ b/drivers/net/appletalk/ipddp.c @@ -284,8 +284,12 @@ static int ipddp_ioctl(struct net_device case SIOCFINDIPDDPRT: spin_lock_bh(&ipddp_route_lock); rp = __ipddp_find_route(&rcp); - if (rp) - memcpy(&rcp2, rp, sizeof(rcp2)); + if (rp) { + memset(&rcp2, 0, sizeof(rcp2)); + rcp2.ip = rp->ip; + rcp2.at = rp->at; + rcp2.flags = rp->flags; + } spin_unlock_bh(&ipddp_route_lock); if (rp) {