kernel.git/net/sched/act_sample.c, branch linux-5.4.y

net/sched: act_sample: fix action bind logic

2023-03-11T15:44:12Z

[ Upstream commit 4a20056a49a1854966562241922f68197f950539 ] The TC architecture allows filters and actions to be created independently. In filters the user can reference action objects using: tc action add action sample ... index 1 tc filter add ... action pedit index 1 In the current code for act_sample this is broken as it checks netlink attributes for create/update before actually checking if we are binding to an existing action. tdc results: 1..29 ok 1 9784 - Add valid sample action with mandatory arguments ok 2 5c91 - Add valid sample action with mandatory arguments and continue control action ok 3 334b - Add valid sample action with mandatory arguments and drop control action ok 4 da69 - Add valid sample action with mandatory arguments and reclassify control action ok 5 13ce - Add valid sample action with mandatory arguments and pipe control action ok 6 1886 - Add valid sample action with mandatory arguments and jump control action ok 7 7571 - Add sample action with invalid rate ok 8 b6d4 - Add sample action with mandatory arguments and invalid control action ok 9 a874 - Add invalid sample action without mandatory arguments ok 10 ac01 - Add invalid sample action without mandatory argument rate ok 11 4203 - Add invalid sample action without mandatory argument group ok 12 14a7 - Add invalid sample action without mandatory argument group ok 13 8f2e - Add valid sample action with trunc argument ok 14 45f8 - Add sample action with maximum rate argument ok 15 ad0c - Add sample action with maximum trunc argument ok 16 83a9 - Add sample action with maximum group argument ok 17 ed27 - Add sample action with invalid rate argument ok 18 2eae - Add sample action with invalid group argument ok 19 6ff3 - Add sample action with invalid trunc size ok 20 2b2a - Add sample action with invalid index ok 21 dee2 - Add sample action with maximum allowed index ok 22 560e - Add sample action with cookie ok 23 704a - Replace existing sample action with new rate argument ok 24 60eb - Replace existing sample action with new group argument ok 25 2cce - Replace existing sample action with new trunc argument ok 26 59d1 - Replace existing sample action with new control argument ok 27 0a6e - Replace sample action with invalid goto chain control ok 28 3872 - Delete sample action with valid index ok 29 a394 - Delete sample action with invalid index Fixes: 5c5670fae430 ("net/sched: Introduce sample tc action") Reviewed-by: Jamal Hadi Salim Signed-off-by: Pedro Tammela Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: sched: lock action when translating it to flow_action infra

2021-12-22T08:29:37Z

[ Upstream commit 7a47281439ba00b11fc098f36695522184ce5a82 ] In order to remove dependency on rtnl lock, take action's tcfa_lock when constructing its representation as flow_action_entry structure. Refactor tcf_sample_get_group() to assume that caller holds tcf_lock and don't take it manually. This callback is only called from flow_action infra representation translator which now calls it with tcf_lock held, so this refactoring is necessary to prevent deadlock. Allocate memory with GFP_ATOMIC flag for ip_tunnel_info copy because tcf_tunnel_info_copy() is only called from flow_action representation infra code with tcf_lock spinlock taken. Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net_sched: defer tcf_idr_insert() in tcf_action_init_1()

2020-10-14T08:33:06Z

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

net/sched: act_sample: don't push mac header on ip6gre ingress

2019-09-21T00:01:59Z

current 'sample' action doesn't push the mac header of ingress packets if they are received by a layer 3 tunnel (like gre or sit); but it forgot to check for gre over ipv6, so the following script: # tc q a dev $d clsact # tc f a dev $d ingress protocol ip flower ip_proto icmp action sample \ > group 100 rate 1 # psample -v -g 100 dumps everything, including outer header and mac, when $d is a gre tunnel over ipv6. Fix this adding a missing label for ARPHRD_IP6GRE devices. Fixes: 5c5670fae430 ("net/sched: Introduce sample tc action") Signed-off-by: Davide Caratti Reviewed-by: Yotam Gigi Signed-off-by: Jakub Kicinski

net: sched: take reference to psample group in flow_action infra

2019-09-16T07:18:03Z

With recent patch set that removed rtnl lock dependency from cls hardware offload API rtnl lock is only taken when reading action data and can be released after action-specific data is parsed into intermediate representation. However, sample action psample group is passed by pointer without obtaining reference to it first, which makes it possible to concurrently overwrite the action and deallocate object pointed by psample_group pointer after rtnl lock is released but before driver finished using the pointer. To prevent such race condition, obtain reference to psample group while it is used by flow_action infra. Extend psample API with function psample_group_take() that increments psample group reference counter. Extend struct tc_action_ops with new get_psample_group() API. Implement the API for action sample using psample_group_take() and already existing psample_group_put() as a destructor. Use it in tc_setup_flow_action() to take reference to psample group pointed to by entry->sample.psample_group and release it in tc_cleanup_flow_action(). Disable bh when taking psample_groups_lock. The lock is now taken while holding action tcf_lock that is used by data path and requires bh to be disabled, so doing the same for psample_groups_lock is necessary to preserve SOFTIRQ-irq-safety. Fixes: 918190f50eb6 ("net: sched: flower: don't take rtnl lock for cls hw offloads API") Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Signed-off-by: David S. Miller

net: sched: act_sample: fix psample group handling on overwrite

2019-08-28T22:53:51Z

Action sample doesn't properly handle psample_group pointer in overwrite case. Following issues need to be fixed: - In tcf_sample_init() function RCU_INIT_POINTER() is used to set s->psample_group, even though we neither setting the pointer to NULL, nor preventing concurrent readers from accessing the pointer in some way. Use rcu_swap_protected() instead to safely reset the pointer. - Old value of s->psample_group is not released or deallocated in any way, which results resource leak. Use psample_group_put() on non-NULL value obtained with rcu_swap_protected(). - The function psample_group_put() that released reference to struct psample_group pointed by rcu-pointer s->psample_group doesn't respect rcu grace period when deallocating it. Extend struct psample_group with rcu head and use kfree_rcu when freeing it. Fixes: 5c5670fae430 ("net/sched: Introduce sample tc action") Signed-off-by: Vlad Buslov Signed-off-by: David S. Miller

net_sched: fix a NULL pointer deref in ipt action

2019-08-27T22:05:58Z

The net pointer in struct xt_tgdtor_param is not explicitly initialized therefore is still NULL when dereferencing it. So we have to find a way to pass the correct net pointer to ipt_destroy_target(). The best way I find is just saving the net pointer inside the per netns struct tcf_idrinfo, which could make this patch smaller. Fixes: 0c66dc1ea3f0 ("netfilter: conntrack: register hooks in netns when needed by ruleset") Reported-and-tested-by: itugrok@yahoo.com Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net: sched: use temporary variable for actions indexes

2019-08-05T17:59:14Z

Currently init call of all actions (except ipt) init their 'parm' structure as a direct pointer to nla data in skb. This leads to race condition when some of the filter actions were initialized successfully (and were assigned with idr action index that was written directly into nla data), but then were deleted and retried (due to following action module missing or classifier-initiated retry), in which case action init code tries to insert action to idr with index that was assigned on previous iteration. During retry the index can be reused by another action that was inserted concurrently, which causes unintended action sharing between filters. To fix described race condition, save action idr index to temporary stack-allocated variable instead on nla data. Fixes: 0190c1d452a9 ("net: sched: atomically check-allocate action") Signed-off-by: Dmytro Linkin Signed-off-by: Vlad Buslov Acked-by: Cong Wang Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

netlink: make validation more configurable for future strictness

2019-04-27T21:07:21Z

We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg Signed-off-by: David S. Miller