From: Cong Wang Date: Wed, 23 Sep 2020 03:56:23 +0000 (-0700) Subject: net_sched: defer tcf_idr_insert() in tcf_action_init_1() X-Git-Tag: v5.8.15~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1e02bbf908d35c98aa673ea7fdd7d1de8bcc0adc;p=thirdparty%2Fkernel%2Fstable.git net_sched: defer tcf_idr_insert() in tcf_action_init_1() commit e49d8c22f1261c43a986a7fdbf677ac309682a07 upstream. All TC actions call tcf_idr_insert() for new action at the end of their ->init(), so we can actually move it to a central place in tcf_action_init_1(). And once the action is inserted into the global IDR, other parallel process could free it immediately as its refcnt is still 1, so we can not fail after this, we need to move it after the goto action validation to avoid handling the failure case after insertion. This is found during code review, is not directly triggered by syzbot. And this prepares for the next patch. Cc: Vlad Buslov Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/include/net/act_api.h b/include/net/act_api.h index 8c39348806705..7dc88ebb6e3e7 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -166,8 +166,6 @@ int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index, struct nlattr *est, struct tc_action **a, const struct tc_action_ops *ops, int bind, u32 flags); -void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a); - void tcf_idr_cleanup(struct tc_action_net *tn, u32 index); int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, struct tc_action **a, int bind); diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 8ac7eb0a83096..e6459c183664c 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -467,17 +467,6 @@ int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index, } EXPORT_SYMBOL(tcf_idr_create_from_flags); -void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a) -{ - struct tcf_idrinfo *idrinfo = tn->idrinfo; - - mutex_lock(&idrinfo->lock); - /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ - WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index))); - mutex_unlock(&idrinfo->lock); -} -EXPORT_SYMBOL(tcf_idr_insert); - /* Cleanup idr index that was allocated but not initialized. */ void tcf_idr_cleanup(struct tc_action_net *tn, u32 index) @@ -902,6 +891,16 @@ static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = { [TCA_ACT_HW_STATS] = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY), }; +static void tcf_idr_insert(struct tc_action *a) +{ + struct tcf_idrinfo *idrinfo = a->idrinfo; + + mutex_lock(&idrinfo->lock); + /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ + WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index))); + mutex_unlock(&idrinfo->lock); +} + struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, @@ -989,6 +988,16 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, if (err < 0) goto err_mod; + if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN) && + !rcu_access_pointer(a->goto_chain)) { + tcf_action_destroy_1(a, bind); + NL_SET_ERR_MSG(extack, "can't use goto chain with NULL chain"); + return ERR_PTR(-EINVAL); + } + + if (err == ACT_P_CREATED) + tcf_idr_insert(a); + if (!name && tb[TCA_ACT_COOKIE]) tcf_set_action_cookie(&a->act_cookie, cookie); @@ -1002,13 +1011,6 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, if (err != ACT_P_CREATED) module_put(a_o->owner); - if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN) && - !rcu_access_pointer(a->goto_chain)) { - tcf_action_destroy_1(a, bind); - NL_SET_ERR_MSG(extack, "can't use goto chain with NULL chain"); - return ERR_PTR(-EINVAL); - } - return a; err_mod: diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c index 54d5652cfe6ca..a4c7ba35a3438 100644 --- a/net/sched/act_bpf.c +++ b/net/sched/act_bpf.c @@ -365,9 +365,7 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (res == ACT_P_CREATED) { - tcf_idr_insert(tn, *act); - } else { + if (res != ACT_P_CREATED) { /* make sure the program being replaced is no longer executing */ synchronize_rcu(); tcf_bpf_cfg_cleanup(&old); diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c index f901421b0634d..e19885d7fe2cb 100644 --- a/net/sched/act_connmark.c +++ b/net/sched/act_connmark.c @@ -139,7 +139,6 @@ static int tcf_connmark_init(struct net *net, struct nlattr *nla, ci->net = net; ci->zone = parm->zone; - tcf_idr_insert(tn, *a); ret = ACT_P_CREATED; } else if (ret > 0) { ci = to_connmark(*a); diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c index c60674cf25c4f..8b3f45cdc319d 100644 --- a/net/sched/act_csum.c +++ b/net/sched/act_csum.c @@ -110,9 +110,6 @@ static int tcf_csum_init(struct net *net, struct nlattr *nla, if (params_new) kfree_rcu(params_new, rcu); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); - return ret; put_chain: if (goto_ch) diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c index 41d8440deaf14..0eb4722cf7cd9 100644 --- a/net/sched/act_ct.c +++ b/net/sched/act_ct.c @@ -1293,8 +1293,6 @@ static int tcf_ct_init(struct net *net, struct nlattr *nla, tcf_chain_put_by_act(goto_ch); if (params) call_rcu(¶ms->rcu, tcf_ct_params_free); - if (res == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return res; diff --git a/net/sched/act_ctinfo.c b/net/sched/act_ctinfo.c index b5042f3ea079e..6084300e51adb 100644 --- a/net/sched/act_ctinfo.c +++ b/net/sched/act_ctinfo.c @@ -269,9 +269,6 @@ static int tcf_ctinfo_init(struct net *net, struct nlattr *nla, if (cp_new) kfree_rcu(cp_new, rcu); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); - return ret; put_chain: diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c index 4160657727196..1a29751ae63b5 100644 --- a/net/sched/act_gact.c +++ b/net/sched/act_gact.c @@ -140,8 +140,6 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; release_idr: tcf_idr_release(*a, bind); diff --git a/net/sched/act_gate.c b/net/sched/act_gate.c index 323ae7f6315d4..c86e7fa7b2208 100644 --- a/net/sched/act_gate.c +++ b/net/sched/act_gate.c @@ -437,9 +437,6 @@ static int tcf_gate_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); - return ret; chain_put: diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c index 5c568757643b2..a2ddea04183af 100644 --- a/net/sched/act_ife.c +++ b/net/sched/act_ife.c @@ -627,9 +627,6 @@ static int tcf_ife_init(struct net *net, struct nlattr *nla, if (p) kfree_rcu(p, rcu); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); - return ret; metadata_parse_err: if (goto_ch) diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c index 400a2cfe84522..8dc3bec0d3258 100644 --- a/net/sched/act_ipt.c +++ b/net/sched/act_ipt.c @@ -189,8 +189,6 @@ static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla, ipt->tcfi_t = t; ipt->tcfi_hook = hook; spin_unlock_bh(&ipt->tcf_lock); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; err3: diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index 83dd82fc9f40c..cd3a7f814fc8c 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -194,8 +194,6 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, spin_lock(&mirred_list_lock); list_add(&m->tcfm_list, &mirred_list); spin_unlock(&mirred_list_lock); - - tcf_idr_insert(tn, *a); } return ret; diff --git a/net/sched/act_mpls.c b/net/sched/act_mpls.c index 8118e26409796..e298ec3b3c9e3 100644 --- a/net/sched/act_mpls.c +++ b/net/sched/act_mpls.c @@ -273,8 +273,6 @@ static int tcf_mpls_init(struct net *net, struct nlattr *nla, if (p) kfree_rcu(p, rcu); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: if (goto_ch) diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c index 855a6fa16a621..1ebd2a86d980f 100644 --- a/net/sched/act_nat.c +++ b/net/sched/act_nat.c @@ -93,9 +93,6 @@ static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); - return ret; release_idr: tcf_idr_release(*a, bind); diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c index d41d6200d9dec..ed1700fe662e1 100644 --- a/net/sched/act_pedit.c +++ b/net/sched/act_pedit.c @@ -238,8 +238,6 @@ static int tcf_pedit_init(struct net *net, struct nlattr *nla, spin_unlock_bh(&p->tcf_lock); if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: diff --git a/net/sched/act_police.c b/net/sched/act_police.c index 8b7a0ac96c516..2d236b9a411f0 100644 --- a/net/sched/act_police.c +++ b/net/sched/act_police.c @@ -201,8 +201,6 @@ static int tcf_police_init(struct net *net, struct nlattr *nla, if (new) kfree_rcu(new, rcu); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; failure: diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c index 5e2df590bb58a..3ebf9ede3cf10 100644 --- a/net/sched/act_sample.c +++ b/net/sched/act_sample.c @@ -116,8 +116,6 @@ static int tcf_sample_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: if (goto_ch) diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c index 9813ca4006dd1..a4f3d0f0daa96 100644 --- a/net/sched/act_simple.c +++ b/net/sched/act_simple.c @@ -157,8 +157,6 @@ static int tcf_simp_init(struct net *net, struct nlattr *nla, goto release_idr; } - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: if (goto_ch) diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c index b2b3faa57294c..8012ae84847b8 100644 --- a/net/sched/act_skbedit.c +++ b/net/sched/act_skbedit.c @@ -224,8 +224,6 @@ static int tcf_skbedit_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: if (goto_ch) diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c index 39e6d94cfafbf..81a1c67335be6 100644 --- a/net/sched/act_skbmod.c +++ b/net/sched/act_skbmod.c @@ -190,8 +190,6 @@ static int tcf_skbmod_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: if (goto_ch) diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c index 536c4bc31be60..23cf8469a2e7c 100644 --- a/net/sched/act_tunnel_key.c +++ b/net/sched/act_tunnel_key.c @@ -536,9 +536,6 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla, if (goto_ch) tcf_chain_put_by_act(goto_ch); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); - return ret; put_chain: diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c index c91d3958fcbb8..68137d7519d01 100644 --- a/net/sched/act_vlan.c +++ b/net/sched/act_vlan.c @@ -229,8 +229,6 @@ static int tcf_vlan_init(struct net *net, struct nlattr *nla, if (p) kfree_rcu(p, rcu); - if (ret == ACT_P_CREATED) - tcf_idr_insert(tn, *a); return ret; put_chain: if (goto_ch)