From fd6d433865a2ad1f7e018ef80408cb3dc3be1ab3 Mon Sep 17 00:00:00 2001 From: Davide Caratti Date: Wed, 28 Nov 2018 18:43:42 +0100 Subject: [PATCH] net/sched: act_police: fix memory leak in case of invalid control action when users set an invalid control action, kmemleak complains as follows: # echo clear >/sys/kernel/debug/kmemleak # ./tdc.py -e b48b Test b48b: Add police action with exceed goto chain control action All test results: 1..1 ok 1 - b48b # Add police action with exceed goto chain control action about to flush the tap output if tests need to be skipped done flushing skipped test tap output # echo scan >/sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak unreferenced object 0xffffa0fafbc3dde0 (size 96): comm "tc", pid 2358, jiffies 4294922738 (age 17.022s) hex dump (first 32 bytes): 2a 00 00 20 00 00 00 00 00 00 7d 00 00 00 00 00 *.. ......}..... f8 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000648803d2>] tcf_action_init_1+0x384/0x4c0 [<00000000cb69382e>] tcf_action_init+0x12b/0x1a0 [<00000000847ef0d4>] tcf_action_add+0x73/0x170 [<0000000093656e14>] tc_ctl_action+0x122/0x160 [<0000000023c98e32>] rtnetlink_rcv_msg+0x263/0x2d0 [<000000003493ae9c>] netlink_rcv_skb+0x4d/0x130 [<00000000de63f8ba>] netlink_unicast+0x209/0x2d0 [<00000000c3da0ebe>] netlink_sendmsg+0x2c1/0x3c0 [<000000007a9e0753>] sock_sendmsg+0x33/0x40 [<00000000457c6d2e>] ___sys_sendmsg+0x2a0/0x2f0 [<00000000c5c6a086>] __sys_sendmsg+0x5e/0xa0 [<00000000446eafce>] do_syscall_64+0x5b/0x180 [<000000004aa871f2>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [<00000000450c38ef>] 0xffffffffffffffff change tcf_police_init() to avoid leaking 'new' in case TCA_POLICE_RESULT contains TC_ACT_GOTO_CHAIN extended action. Fixes: c08f5ed5d625 ("net/sched: act_police: disallow 'goto chain' on fallback control action") Reported-by: Dan Carpenter Signed-off-by: Davide Caratti Acked-by: Cong Wang Signed-off-by: David S. Miller --- net/sched/act_police.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/net/sched/act_police.c b/net/sched/act_police.c index 37c9b8f0e10f..ec8ec55e0fe8 100644 --- a/net/sched/act_police.c +++ b/net/sched/act_police.c @@ -85,7 +85,7 @@ static int tcf_police_init(struct net *net, struct nlattr *nla, int ovr, int bind, bool rtnl_held, struct netlink_ext_ack *extack) { - int ret = 0, err; + int ret = 0, tcfp_result = TC_ACT_OK, err, size; struct nlattr *tb[TCA_POLICE_MAX + 1]; struct tc_police *parm; struct tcf_police *police; @@ -93,7 +93,6 @@ static int tcf_police_init(struct net *net, struct nlattr *nla, struct tc_action_net *tn = net_generic(net, police_net_id); struct tcf_police_params *new; bool exists = false; - int size; if (nla == NULL) return -EINVAL; @@ -160,6 +159,16 @@ static int tcf_police_init(struct net *net, struct nlattr *nla, goto failure; } + if (tb[TCA_POLICE_RESULT]) { + tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]); + if (TC_ACT_EXT_CMP(tcfp_result, TC_ACT_GOTO_CHAIN)) { + NL_SET_ERR_MSG(extack, + "goto chain not allowed on fallback"); + err = -EINVAL; + goto failure; + } + } + new = kzalloc(sizeof(*new), GFP_KERNEL); if (unlikely(!new)) { err = -ENOMEM; @@ -167,6 +176,7 @@ static int tcf_police_init(struct net *net, struct nlattr *nla, } /* No failure allowed after this point */ + new->tcfp_result = tcfp_result; new->tcfp_mtu = parm->mtu; if (!new->tcfp_mtu) { new->tcfp_mtu = ~0; @@ -196,16 +206,6 @@ static int tcf_police_init(struct net *net, struct nlattr *nla, if (tb[TCA_POLICE_AVRATE]) new->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]); - if (tb[TCA_POLICE_RESULT]) { - new->tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]); - if (TC_ACT_EXT_CMP(new->tcfp_result, TC_ACT_GOTO_CHAIN)) { - NL_SET_ERR_MSG(extack, - "goto chain not allowed on fallback"); - err = -EINVAL; - goto failure; - } - } - spin_lock_bh(&police->tcf_lock); spin_lock_bh(&police->tcfp_lock); police->tcfp_t_c = ktime_get_ns(); -- 2.30.2