[PATCH] net/appletalk: fix minor pointer leak to userspace in SIOCFINDIPDDPRT
From: Willy Tarreau <w@1wt.eu>
Date: 2018-09-12 05:36:44
Also in:
lkml
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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@google.com> Signed-off-by: Willy Tarreau <w@1wt.eu> --- drivers/net/appletalk/ipddp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/net/appletalk/ipddp.c b/drivers/net/appletalk/ipddp.c
index 9375cef..3d27616 100644
--- a/drivers/net/appletalk/ipddp.c
+++ b/drivers/net/appletalk/ipddp.c@@ -283,8 +283,12 @@ static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 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) {
--
2.8.0.rc2.1.gbe9624a