From: Taehee Yoo ap420073@gmail.com
[ Upstream commit 173756b86803655d70af7732079b3aa935e6ab68 ]
hsr_get_node_{list/status}() are not under rtnl_lock() because they are callback functions of generic netlink. But they use __dev_get_by_index() without rtnl_lock(). So, it would use unsafe data. In order to fix it, rcu_read_lock() and dev_get_by_index_rcu() are used instead of __dev_get_by_index().
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)") Signed-off-by: Taehee Yoo ap420073@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/hsr/hsr_framereg.c | 10 ++-------- net/hsr/hsr_netlink.c | 43 +++++++++++++++++++++---------------------- 2 files changed, 23 insertions(+), 30 deletions(-)
--- a/net/hsr/hsr_framereg.c +++ b/net/hsr/hsr_framereg.c @@ -468,13 +468,9 @@ int hsr_get_node_data(struct hsr_priv *h struct hsr_port *port; unsigned long tdiff;
- - rcu_read_lock(); node = find_node_by_AddrA(&hsr->node_db, addr); - if (!node) { - rcu_read_unlock(); - return -ENOENT; /* No such entry */ - } + if (!node) + return -ENOENT;
ether_addr_copy(addr_b, node->MacAddressB);
@@ -509,7 +505,5 @@ int hsr_get_node_data(struct hsr_priv *h *addr_b_ifindex = -1; }
- rcu_read_unlock(); - return 0; } --- a/net/hsr/hsr_netlink.c +++ b/net/hsr/hsr_netlink.c @@ -259,17 +259,16 @@ static int hsr_get_node_status(struct sk if (!na) goto invalid;
- hsr_dev = __dev_get_by_index(genl_info_net(info), - nla_get_u32(info->attrs[HSR_A_IFINDEX])); + rcu_read_lock(); + hsr_dev = dev_get_by_index_rcu(genl_info_net(info), + nla_get_u32(info->attrs[HSR_A_IFINDEX])); if (!hsr_dev) - goto invalid; + goto rcu_unlock; if (!is_hsr_master(hsr_dev)) - goto invalid; - + goto rcu_unlock;
/* Send reply */ - - skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); if (!skb_out) { res = -ENOMEM; goto fail; @@ -321,12 +320,10 @@ static int hsr_get_node_status(struct sk res = nla_put_u16(skb_out, HSR_A_IF1_SEQ, hsr_node_if1_seq); if (res < 0) goto nla_put_failure; - rcu_read_lock(); port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A); if (port) res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX, port->dev->ifindex); - rcu_read_unlock(); if (res < 0) goto nla_put_failure;
@@ -336,20 +333,22 @@ static int hsr_get_node_status(struct sk res = nla_put_u16(skb_out, HSR_A_IF2_SEQ, hsr_node_if2_seq); if (res < 0) goto nla_put_failure; - rcu_read_lock(); port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B); if (port) res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX, port->dev->ifindex); - rcu_read_unlock(); if (res < 0) goto nla_put_failure;
+ rcu_read_unlock(); + genlmsg_end(skb_out, msg_head); genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);
return 0;
+rcu_unlock: + rcu_read_unlock(); invalid: netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL); return 0; @@ -359,6 +358,7 @@ nla_put_failure: /* Fall through */
fail: + rcu_read_unlock(); return res; }
@@ -385,17 +385,16 @@ static int hsr_get_node_list(struct sk_b if (!na) goto invalid;
- hsr_dev = __dev_get_by_index(genl_info_net(info), - nla_get_u32(info->attrs[HSR_A_IFINDEX])); + rcu_read_lock(); + hsr_dev = dev_get_by_index_rcu(genl_info_net(info), + nla_get_u32(info->attrs[HSR_A_IFINDEX])); if (!hsr_dev) - goto invalid; + goto rcu_unlock; if (!is_hsr_master(hsr_dev)) - goto invalid; - + goto rcu_unlock;
/* Send reply */ - - skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); if (!skb_out) { res = -ENOMEM; goto fail; @@ -415,14 +414,11 @@ static int hsr_get_node_list(struct sk_b
hsr = netdev_priv(hsr_dev);
- rcu_read_lock(); pos = hsr_get_next_node(hsr, NULL, addr); while (pos) { res = nla_put(skb_out, HSR_A_NODE_ADDR, ETH_ALEN, addr); - if (res < 0) { - rcu_read_unlock(); + if (res < 0) goto nla_put_failure; - } pos = hsr_get_next_node(hsr, pos, addr); } rcu_read_unlock(); @@ -432,6 +428,8 @@ static int hsr_get_node_list(struct sk_b
return 0;
+rcu_unlock: + rcu_read_unlock(); invalid: netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL); return 0; @@ -441,6 +439,7 @@ nla_put_failure: /* Fall through */
fail: + rcu_read_unlock(); return res; }