From e255e11e66da8281e337e4e352956e8a4999fca4 Mon Sep 17 00:00:00 2001 From: Wang Hai Date: Tue, 24 Nov 2020 15:17:28 +0800 Subject: [PATCH] ipv6: addrlabel: fix possible memory leak in ip6addrlbl_net_init kmemleak report a memory leak as follows: unreferenced object 0xffff8880059c6a00 (size 64): comm "ip", pid 23696, jiffies 4296590183 (age 1755.384s) hex dump (first 32 bytes): 20 01 00 10 00 00 00 00 00 00 00 00 00 00 00 00 ............... 1c 00 00 00 00 00 00 00 00 00 00 00 07 00 00 00 ................ backtrace: [<00000000aa4e7a87>] ip6addrlbl_add+0x90/0xbb0 [<0000000070b8d7f1>] ip6addrlbl_net_init+0x109/0x170 [<000000006a9ca9d4>] ops_init+0xa8/0x3c0 [<000000002da57bf2>] setup_net+0x2de/0x7e0 [<000000004e52d573>] copy_net_ns+0x27d/0x530 [<00000000b07ae2b4>] create_new_namespaces+0x382/0xa30 [<000000003b76d36f>] unshare_nsproxy_namespaces+0xa1/0x1d0 [<0000000030653721>] ksys_unshare+0x3a4/0x780 [<0000000007e82e40>] __x64_sys_unshare+0x2d/0x40 [<0000000031a10c08>] do_syscall_64+0x33/0x40 [<0000000099df30e7>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 We should free all rules when we catch an error in ip6addrlbl_net_init(). otherwise a memory leak will occur. Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") Reported-by: Hulk Robot Signed-off-by: Wang Hai Link: https://lore.kernel.org/r/20201124071728.8385-1-wanghai38@huawei.com Signed-off-by: Jakub Kicinski --- net/ipv6/addrlabel.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c index 642fc6ac13d2..8a22486cf270 100644 --- a/net/ipv6/addrlabel.c +++ b/net/ipv6/addrlabel.c @@ -306,7 +306,9 @@ static int ip6addrlbl_del(struct net *net, /* add default label */ static int __net_init ip6addrlbl_net_init(struct net *net) { - int err = 0; + struct ip6addrlbl_entry *p = NULL; + struct hlist_node *n; + int err; int i; ADDRLABEL(KERN_DEBUG "%s\n", __func__); @@ -315,14 +317,20 @@ static int __net_init ip6addrlbl_net_init(struct net *net) INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head); for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) { - int ret = ip6addrlbl_add(net, - ip6addrlbl_init_table[i].prefix, - ip6addrlbl_init_table[i].prefixlen, - 0, - ip6addrlbl_init_table[i].label, 0); - /* XXX: should we free all rules when we catch an error? */ - if (ret && (!err || err != -ENOMEM)) - err = ret; + err = ip6addrlbl_add(net, + ip6addrlbl_init_table[i].prefix, + ip6addrlbl_init_table[i].prefixlen, + 0, + ip6addrlbl_init_table[i].label, 0); + if (err) + goto err_ip6addrlbl_add; + } + return 0; + +err_ip6addrlbl_add: + hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) { + hlist_del_rcu(&p->list); + kfree_rcu(p, rcu); } return err; } -- 2.34.1