From 3909642034ffd7a8906ff3f2b2a71455bf39e7f6 Mon Sep 17 00:00:00 2001 From: Matan Barak Date: Thu, 15 Oct 2015 15:01:03 +0300 Subject: [PATCH] IB/core: Fix use after free of ifa When using ifup/ifdown while executing enum_netdev_ipv4_ips, ifa could become invalid and cause use after free error. Fixing it by protecting with RCU lock. Fixes: 03db3a2d81e6 ('IB/core: Add RoCE GID table management') Signed-off-by: Matan Barak Signed-off-by: Doug Ledford --- drivers/infiniband/core/roce_gid_mgmt.c | 35 +++++++++++++++++++------ 1 file changed, 27 insertions(+), 8 deletions(-) diff --git a/drivers/infiniband/core/roce_gid_mgmt.c b/drivers/infiniband/core/roce_gid_mgmt.c index 6b24cba1e474..178f98482e13 100644 --- a/drivers/infiniband/core/roce_gid_mgmt.c +++ b/drivers/infiniband/core/roce_gid_mgmt.c @@ -250,25 +250,44 @@ static void enum_netdev_ipv4_ips(struct ib_device *ib_dev, u8 port, struct net_device *ndev) { struct in_device *in_dev; + struct sin_list { + struct list_head list; + struct sockaddr_in ip; + }; + struct sin_list *sin_iter; + struct sin_list *sin_temp; + LIST_HEAD(sin_list); if (ndev->reg_state >= NETREG_UNREGISTERING) return; - in_dev = in_dev_get(ndev); - if (!in_dev) + rcu_read_lock(); + in_dev = __in_dev_get_rcu(ndev); + if (!in_dev) { + rcu_read_unlock(); return; + } for_ifa(in_dev) { - struct sockaddr_in ip; + struct sin_list *entry = kzalloc(sizeof(*entry), GFP_ATOMIC); - ip.sin_family = AF_INET; - ip.sin_addr.s_addr = ifa->ifa_address; - update_gid_ip(GID_ADD, ib_dev, port, ndev, - (struct sockaddr *)&ip); + if (!entry) { + pr_warn("roce_gid_mgmt: couldn't allocate entry for IPv4 update\n"); + continue; + } + entry->ip.sin_family = AF_INET; + entry->ip.sin_addr.s_addr = ifa->ifa_address; + list_add_tail(&entry->list, &sin_list); } endfor_ifa(in_dev); + rcu_read_unlock(); - in_dev_put(in_dev); + list_for_each_entry_safe(sin_iter, sin_temp, &sin_list, list) { + update_gid_ip(GID_ADD, ib_dev, port, ndev, + (struct sockaddr *)&sin_iter->ip); + list_del(&sin_iter->list); + kfree(sin_iter); + } } static void enum_netdev_ipv6_ips(struct ib_device *ib_dev, -- 2.20.1