| Message ID | d0a72d1371e790505a8141592c6af904c9b24031.1536079973.git.dcaratti@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net] net/sched: fix memory leak in act_tunnel_key_init() | expand |
On Tue, Sep 4, 2018 at 10:00 AM Davide Caratti <dcaratti@redhat.com> wrote: > > If users try to install act_tunnel_key 'set' rules with duplicate values > of 'index', the tunnel metadata are allocated, but never released. Then, > kmemleak complains as follows: Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
From: Davide Caratti <dcaratti@redhat.com> Date: Tue, 4 Sep 2018 19:00:19 +0200 > If users try to install act_tunnel_key 'set' rules with duplicate values > of 'index', the tunnel metadata are allocated, but never released. Then, > kmemleak complains as follows: ... > This problem theoretically happens also in case users attempt to setup a > geneve rule having wrong configuration data, or when the kernel fails to > allocate 'params_new'. Ensure that tunnel_key_init() releases the tunnel > metadata also in the above conditions. > > Addresses-Coverity-ID: 1373974 ("Resource leak") > Fixes: d0f6dd8a914f4 ("net/sched: Introduce act_tunnel_key") > Fixes: 0ed5269f9e41f ("net/sched: add tunnel option support to act_tunnel_key") > Signed-off-by: Davide Caratti <dcaratti@redhat.com> Applied and queued up for -stable.
diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c index 420759153d5f..28d58bbc953e 100644 --- a/net/sched/act_tunnel_key.c +++ b/net/sched/act_tunnel_key.c @@ -317,7 +317,7 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla, &metadata->u.tun_info, opts_len, extack); if (ret < 0) - goto err_out; + goto release_tun_meta; } metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX; @@ -333,23 +333,24 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla, &act_tunnel_key_ops, bind, true); if (ret) { NL_SET_ERR_MSG(extack, "Cannot create TC IDR"); - goto err_out; + goto release_tun_meta; } ret = ACT_P_CREATED; } else if (!ovr) { - tcf_idr_release(*a, bind); NL_SET_ERR_MSG(extack, "TC IDR already exists"); - return -EEXIST; + ret = -EEXIST; + goto release_tun_meta; } t = to_tunnel_key(*a); params_new = kzalloc(sizeof(*params_new), GFP_KERNEL); if (unlikely(!params_new)) { - tcf_idr_release(*a, bind); NL_SET_ERR_MSG(extack, "Cannot allocate tunnel key parameters"); - return -ENOMEM; + ret = -ENOMEM; + exists = true; + goto release_tun_meta; } params_new->tcft_action = parm->t_action; params_new->tcft_enc_metadata = metadata; @@ -367,6 +368,9 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla, return ret; +release_tun_meta: + dst_release(&metadata->dst); + err_out: if (exists) tcf_idr_release(*a, bind);
If users try to install act_tunnel_key 'set' rules with duplicate values of 'index', the tunnel metadata are allocated, but never released. Then, kmemleak complains as follows: # tc a a a tunnel_key set src_ip 1.1.1.1 dst_ip 2.2.2.2 id 42 index 111 # echo clear > /sys/kernel/debug/kmemleak # tc a a a tunnel_key set src_ip 1.1.1.1 dst_ip 2.2.2.2 id 42 index 111 Error: TC IDR already exists. We have an error talking to the kernel # echo scan > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak unreferenced object 0xffff8800574e6c80 (size 256): comm "tc", pid 5617, jiffies 4298118009 (age 57.990s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 1c e8 b0 ff ff ff ff ................ 81 24 c2 ad ff ff ff ff 00 00 00 00 00 00 00 00 .$.............. backtrace: [<00000000b7afbf4e>] tunnel_key_init+0x8a5/0x1800 [act_tunnel_key] [<000000007d98fccd>] tcf_action_init_1+0x698/0xac0 [<0000000099b8f7cc>] tcf_action_init+0x15c/0x590 [<00000000dc60eebe>] tc_ctl_action+0x336/0x5c2 [<000000002f5a2f7d>] rtnetlink_rcv_msg+0x357/0x8e0 [<000000000bfe7575>] netlink_rcv_skb+0x124/0x350 [<00000000edab656f>] netlink_unicast+0x40f/0x5d0 [<00000000b322cdcb>] netlink_sendmsg+0x6e8/0xba0 [<0000000063d9d490>] sock_sendmsg+0xb3/0xf0 [<00000000f0d3315a>] ___sys_sendmsg+0x654/0x960 [<00000000c06cbd42>] __sys_sendmsg+0xd3/0x170 [<00000000ce72e4b0>] do_syscall_64+0xa5/0x470 [<000000005caa2d97>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<00000000fac1b476>] 0xffffffffffffffff This problem theoretically happens also in case users attempt to setup a geneve rule having wrong configuration data, or when the kernel fails to allocate 'params_new'. Ensure that tunnel_key_init() releases the tunnel metadata also in the above conditions. Addresses-Coverity-ID: 1373974 ("Resource leak") Fixes: d0f6dd8a914f4 ("net/sched: Introduce act_tunnel_key") Fixes: 0ed5269f9e41f ("net/sched: add tunnel option support to act_tunnel_key") Signed-off-by: Davide Caratti <dcaratti@redhat.com> --- net/sched/act_tunnel_key.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)