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2023-07-31net/sched: cls_route: No longer copy tcf_result on update to avoid ↵valis
use-after-free When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. Fix this by no longer copying the tcf_result struct from the old filter. Fixes: 1109c00547fc ("net: sched: RCU cls_route") Reported-by: valis <sec@valis.email> Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg> Signed-off-by: valis <sec@valis.email> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Reviewed-by: Pedro Tammela <pctammela@mojatatu.com> Reviewed-by: M A Ramdhan <ramdhan@starlabs.sg> Link: https://lore.kernel.org/r/20230729123202.72406-4-jhs@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-09net/sched: avoid indirect classify functions on retpoline kernelsPedro Tammela
Expose the necessary tc classifier functions and wire up cls_api to use direct calls in retpoline kernels. Signed-off-by: Pedro Tammela <pctammela@mojatatu.com> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-02net: sched: use tc_cls_bind_class() in filterZhengchao Shao
Use tc_cls_bind_class() in filter. Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-20net/sched: use tc_cls_stats_dump() in filterZhengchao Shao
use tc_cls_stats_dump() in filter. Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-26net_sched: remove impossible conditionsDan Carpenter
We no longer allow "handle" to be zero, so there is no need to check for that. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/Ywd4NIoS4aiilnMv@kili Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-15net_sched: cls_route: disallow handle of 0Jamal Hadi Salim
Follows up on: https://lore.kernel.org/all/20220809170518.164662-1-cascardo@canonical.com/ handle of 0 implies from/to of universe realm which is not very sensible. Lets see what this patch will do: $sudo tc qdisc add dev $DEV root handle 1:0 prio //lets manufacture a way to insert handle of 0 $sudo tc filter add dev $DEV parent 1:0 protocol ip prio 100 \ route to 0 from 0 classid 1:10 action ok //gets rejected... Error: handle of 0 is not valid. We have an error talking to the kernel, -1 //lets create a legit entry.. sudo tc filter add dev $DEV parent 1:0 protocol ip prio 100 route from 10 \ classid 1:10 action ok //what did the kernel insert? $sudo tc filter ls dev $DEV parent 1:0 filter protocol ip pref 100 route chain 0 filter protocol ip pref 100 route chain 0 fh 0x000a8000 flowid 1:10 from 10 action order 1: gact action pass random type none pass val 0 index 1 ref 1 bind 1 //Lets try to replace that legit entry with a handle of 0 $ sudo tc filter replace dev $DEV parent 1:0 protocol ip prio 100 \ handle 0x000a8000 route to 0 from 0 classid 1:10 action drop Error: Replacing with handle of 0 is invalid. We have an error talking to the kernel, -1 And last, lets run Cascardo's POC: $ ./poc 0 0 -22 -22 -22 Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-10net_sched: cls_route: remove from list when handle is 0Thadeu Lima de Souza Cascardo
When a route filter is replaced and the old filter has a 0 handle, the old one won't be removed from the hashtable, while it will still be freed. The test was there since before commit 1109c00547fc ("net: sched: RCU cls_route"), when a new filter was not allocated when there was an old one. The old filter was reused and the reinserting would only be necessary if an old filter was replaced. That was still wrong for the same case where the old handle was 0. Remove the old filter from the list independently from its handle value. This fixes CVE-2022-2588, also reported as ZDI-CAN-17440. Reported-by: Zhenpeng Lin <zplin@u.northwestern.edu> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Reviewed-by: Kamal Mostafa <kamal@canonical.com> Cc: <stable@vger.kernel.org> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://lore.kernel.org/r/20220809170518.164662-1-cascardo@canonical.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-02net_sched: refactor TC action init APICong Wang
TC action ->init() API has 10 parameters, it becomes harder to read. Some of them are just boolean and can be replaced by flags. Similarly for the internal API tcf_action_init() and tcf_exts_validate(). This patch converts them to flags and fold them into the upper 16 bits of "flags", whose lower 16 bits are still reserved for user-space. More specifically, the following kernel flags are introduced: TCA_ACT_FLAGS_POLICE replace 'name' in a few contexts, to distinguish whether it is compatible with policer. TCA_ACT_FLAGS_BIND replaces 'bind', to indicate whether this action is bound to a filter. TCA_ACT_FLAGS_REPLACE replaces 'ovr' in most contexts, means we are replacing an existing action. TCA_ACT_FLAGS_NO_RTNL replaces 'rtnl_held' but has the opposite meaning, because we still hold RTNL in most cases. The only user-space flag TCA_ACT_FLAGS_NO_PERCPU_STATS is untouched and still stored as before. I have tested this patch with tdc and I do not see any failure related to this patch. Tested-by: Vlad Buslov <vladbu@nvidia.com> Acked-by: Jamal Hadi Salim<jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-16net_sched: cls_route: remove the right filter from hashtableCong Wang
route4_change() allocates a new filter and copies values from the old one. After the new filter is inserted into the hash table, the old filter should be removed and freed, as the final step of the update. However, the current code mistakenly removes the new one. This looks apparently wrong to me, and it causes double "free" and use-after-free too, as reported by syzbot. Reported-and-tested-by: syzbot+f9b32aaacd60305d9687@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+2f8c233f131943d6056d@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+9c2df9fd5e9445b74e01@syzkaller.appspotmail.com Fixes: 1109c00547fc ("net: sched: RCU cls_route") Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-27net_sched: fix ops->bind_class() implementationsCong Wang
The current implementations of ops->bind_class() are merely searching for classid and updating class in the struct tcf_result, without invoking either of cl_ops->bind_tcf() or cl_ops->unbind_tcf(). This breaks the design of them as qdisc's like cbq use them to count filters too. This is why syzbot triggered the warning in cbq_destroy_class(). In order to fix this, we have to call cl_ops->bind_tcf() and cl_ops->unbind_tcf() like the filter binding path. This patch does so by refactoring out two helper functions __tcf_bind_filter() and __tcf_unbind_filter(), which are lockless and accept a Qdisc pointer, then teaching each implementation to call them correctly. Note, we merely pass the Qdisc pointer as an opaque pointer to each filter, they only need to pass it down to the helper functions without understanding it at all. Fixes: 07d79fc7d94e ("net_sched: add reverse binding for tc class") Reported-and-tested-by: syzbot+0a0596220218fcb603a8@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+63bdb6006961d8c917c6@syzkaller.appspotmail.com Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 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 as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg
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 <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27netlink: make nla_nest_start() add NLA_F_NESTED flagMichal Kubecek
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most netlink based interfaces (including recently added ones) are still not setting it in kernel generated messages. Without the flag, message parsers not aware of attribute semantics (e.g. wireshark dissector or libmnl's mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display the structure of their contents. Unfortunately we cannot just add the flag everywhere as there may be userspace applications which check nlattr::nla_type directly rather than through a helper masking out the flags. Therefore the patch renames nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start() as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually are rewritten to use nla_nest_start(). Except for changes in include/net/netlink.h, the patch was generated using this semantic patch: @@ expression E1, E2; @@ -nla_nest_start(E1, E2) +nla_nest_start_noflag(E1, E2) @@ expression E1, E2; @@ -nla_nest_start_noflag(E1, E2 | NLA_F_NESTED) +nla_nest_start(E1, E2) Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-22net_sched: initialize net pointer inside tcf_exts_init()Cong Wang
For tcindex filter, it is too late to initialize the net pointer in tcf_exts_validate(), as tcf_exts_get_net() requires a non-NULL net pointer. We can just move its initialization into tcf_exts_init(), which just requires an additional parameter. This makes the code in tcindex_alloc_perfect_hash() prettier. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-17net: sched: route: don't set arg->stop in route4_walk() when emptyVlad Buslov
Some classifiers set arg->stop in their implementation of tp->walk() API when empty. Most of classifiers do not adhere to that convention. Do not set arg->stop in route4_walk() to unify tp->walk() behavior among classifier implementations. Fixes: ed76f5edccc9 ("net: sched: protect filter_chain list with filter_chain_lock mutex") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12net: sched: extend proto ops to support unlocked classifiersVlad Buslov
Add 'rtnl_held' flag to tcf proto change, delete, destroy, dump, walk functions to track rtnl lock status. Extend users of these function in cls API to propagate rtnl lock status to them. This allows classifiers to obtain rtnl lock when necessary and to pass rtnl lock status to extensions and driver offload callbacks. Add flags field to tcf proto ops. Add flag value to indicate that classifier doesn't require rtnl lock. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12net: sched: track rtnl lock status when validating extensionsVlad Buslov
Actions API is already updated to not rely on rtnl lock for synchronization. However, it need to be provided with rtnl status when called from classifiers API in order to be able to correctly release the lock when loading kernel module. Extend extension validation function with 'rtnl_held' flag which is passed to actions API. Add new 'rtnl_held' parameter to tcf_exts_validate() in cls API. No classifier is currently updated to support unlocked execution, so pass hardcoded 'true' flag parameter value. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24net_sched: switch to rcu_workCong Wang
Commit 05f0fe6b74db ("RCU, workqueue: Implement rcu_work") introduces new API's for dispatching work in a RCU callback. Now we can just switch to the new API's for tc filters. This could get rid of a lot of code. Cc: Tejun Heo <tj@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-24net: sched: propagate extack to cls->destroy callbacksJakub Kicinski
Propagate extack to cls->destroy callbacks when called from non-error paths. On error paths pass NULL to avoid overwriting the failure message. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19net: sched: cls: add extack support for delete callbackAlexander Aring
This patch adds extack support for classifier delete callback api. This prepares to handle extack support inside each specific classifier implementation. Cc: David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19net: sched: cls: add extack support for tcf_exts_validateAlexander Aring
The tcf_exts_validate function calls the act api change callback. For preparing extack support for act api, this patch adds the extack as parameter for this function which is common used in cls implementations. Furthermore the tcf_exts_validate will call action init callback which prepares the TC action subsystem for extack support. Cc: David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19net: sched: cls: add extack support for change callbackAlexander Aring
This patch adds extack support for classifier change callback api. This prepares to handle extack support inside each specific classifier implementation. Cc: David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17net: sched: introduce block mechanism to handle netif_keep_dst callsJiri Pirko
Couple of classifiers call netif_keep_dst directly on q->dev. That is not possible to do directly for shared blocke where multiple qdiscs are owning the block. So introduce a infrastructure to keep track of the block owners in list and use this list to implement block variant of netif_keep_dst. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-09cls_route: use tcf_exts_get_net() before call_rcu()Cong Wang
Hold netns refcnt before call_rcu() and release it after the tcf_exts_destroy() is done. Note, on ->destroy() path we have to respect the return value of tcf_exts_get_net(), on other paths it should always return true, so we don't need to care. Cc: Lucas Bates <lucasb@mojatatu.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29net_sched: use tcf_queue_work() in route filterCong Wang
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: Chris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-31net_sched: add reverse binding for tc classCong Wang
TC filters when used as classifiers are bound to TC classes. However, there is a hidden difference when adding them in different orders: 1. If we add tc classes before its filters, everything is fine. Logically, the classes exist before we specify their ID's in filters, it is easy to bind them together, just as in the current code base. 2. If we add tc filters before the tc classes they bind, we have to do dynamic lookup in fast path. What's worse, this happens all the time not just once, because on fast path tcf_result is passed on stack, there is no way to propagate back to the one in tc filters. This hidden difference hurts performance silently if we have many tc classes in hierarchy. This patch intends to close this gap by doing the reverse binding when we create a new class, in this case we can actually search all the filters in its parent, match and fixup by classid. And because tcf_result is specific to each type of tc filter, we have to introduce a new ops for each filter to tell how to bind the class. Note, we still can NOT totally get rid of those class lookup in ->enqueue() because cgroup and flow filters have no way to determine the classid at setup time, they still have to go through dynamic lookup. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-07net_sched: use void pointer for filter handleWANG Cong
Now we use 'unsigned long fh' as a pointer in every place, it is safe to convert it to a void pointer now. This gets rid of many casts to pointer. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04net: sched: cls_route: no need to call tcf_exts_change for newly allocated ↵Jiri Pirko
struct As the f struct was allocated right before route4_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04net: sched: remove redundant helpers tcf_exts_is_predicative and ↵Jiri Pirko
tcf_exts_is_available These two helpers are doing the same as tcf_exts_has_actions, so remove them and use tcf_exts_has_actions instead. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21net_sched: remove useless NULL to tp->rootWANG Cong
There is no need to NULL tp->root in ->destroy(), since tp is going to be freed very soon, and existing readers are still safe to read them. For cls_route, we always init its tp->root, so it can't be NULL, we can drop more useless code. Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21net_sched: move the empty tp check from ->destroy() to ->delete()WANG Cong
We could have a race condition where in ->classify() path we dereference tp->root and meanwhile a parallel ->destroy() makes it a NULL. Daniel cured this bug in commit d936377414fa ("net, sched: respect rcu grace period on cls destruction"). This happens when ->destroy() is called for deleting a filter to check if we are the last one in tp, this tp is still linked and visible at that time. The root cause of this problem is the semantic of ->destroy(), it does two things (for non-force case): 1) check if tp is empty 2) if tp is empty we could really destroy it and its caller, if cares, needs to check its return value to see if it is really destroyed. Therefore we can't unlink tp unless we know it is empty. As suggested by Daniel, we could actually move the test logic to ->delete() so that we can safely unlink tp after ->delete() tells us the last one is just deleted and before ->destroy(). Fixes: 1e052be69d04 ("net_sched: destroy proto tp when all filters are gone") Cc: Roi Dayan <roid@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-23net_sched: check NULL on error path in route4_change()WANG Cong
On error path in route4_change(), 'f' could be NULL, so we should check NULL before calling tcf_exts_destroy(). Fixes: b9a24bb76bf6 ("net_sched: properly handle failure case of tcf_exts_init()") Reported-by: kbuild test robot <fengguang.wu@intel.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-19net sched: stylistic cleanupsJamal Hadi Salim
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-22net_sched: properly handle failure case of tcf_exts_init()WANG Cong
After commit 22dc13c837c3 ("net_sched: convert tcf_exts from list to pointer array") we do dynamic allocation in tcf_exts_init(), therefore we need to handle the ENOMEM case properly. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09net_sched: destroy proto tp when all filters are goneCong Wang
Kernel automatically creates a tp for each (kind, protocol, priority) tuple, which has handle 0, when we add a new filter, but it still is left there after we remove our own, unless we don't specify the handle (literally means all the filters under the tuple). For example this one is left: # tc filter show dev eth0 filter parent 8001: protocol arp pref 49152 basic The user-space is hard to clean up these for kernel because filters like u32 are organized in a complex way. So kernel is responsible to remove it after all filters are gone. Each type of filter has its own way to store the filters, so each type has to provide its way to check if all filters are gone. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim<jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-05net_sched: move tp->root allocation into route4_init()WANG Cong
Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09net: sched: cls: use nla_nest_cancel instead of nlmsg_trimJiri Pirko
To cancel nesting, this function is more convenient. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09net: sched: cls: remove unused op put from tcf_proto_opsJiri Pirko
It is never called and implementations are void. So just remove it. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07net: better IFF_XMIT_DST_RELEASE supportEric Dumazet
Testing xmit_more support with netperf and connected UDP sockets, I found strange dst refcount false sharing. Current handling of IFF_XMIT_DST_RELEASE is not optimal. Dropping dst in validate_xmit_skb() is certainly too late in case packet was queued by cpu X but dequeued by cpu Y The logical point to take care of drop/force is in __dev_queue_xmit() before even taking qdisc lock. As Julian Anastasov pointed out, need for skb_dst() might come from some packet schedulers or classifiers. This patch adds new helper to cleanly express needs of various drivers or qdiscs/classifiers. Drivers that need skb_dst() in their ndo_start_xmit() should call following helper in their setup instead of the prior : dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; -> netif_keep_dst(dev); Instead of using a single bit, we use two bits, one being eventually rebuilt in bonding/team drivers. The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being rebuilt in bonding/team. Eventually, we could add something smarter later. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06net: sched: do not use tcf_proto 'tp' argument from call_rcuJohn Fastabend
Using the tcf_proto pointer 'tp' from inside the classifiers callback is not valid because it may have been cleaned up by another call_rcu occuring on another CPU. 'tp' is currently being used by tcf_unbind_filter() in this patch we move instances of tcf_unbind_filter outside of the call_rcu() context. This is safe to do because any running schedulers will either read the valid class field or it will be zeroed. And all schedulers today when the class is 0 do a lookup using the same call used by the tcf_exts_bind(). So even if we have a running classifier hit the null class pointer it will do a lookup and get to the same result. This is particularly fragile at the moment because the only way to verify this is to audit the schedulers call sites. Reported-by: Cong Wang <xiyou.wangconf@gmail.com> Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-28net_sched: remove the first parameter from tcf_exts_destroy()WANG Cong
Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <hadi@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13net: sched: RCU cls_routeJohn Fastabend
RCUify the route classifier. For now however spinlock's are used to protect fastmap cache. The issue here is the fastmap may be read by one CPU while the cache is being updated by another. An array of pointers could be one possible solution. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-27sched, cls: check if we could overwrite actions when changing a filterCong Wang
When actions are attached to a filter, they are a part of the filter itself, so when changing a filter we should allow to overwrite the actions inside as well. In my specific case, when I tried to _append_ a new action to an existing filter which already has an action, I got EEXIST since kernel refused to overwrite the existing one in kernel. This patch checks if we are changing the filter checking NLM_F_CREATE flag (Sigh, filters don't use NLM_F_REPLACE...) and then passes the boolean down to actions. This fixes the problem above. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13net_sched: avoid casting void pointerWANG Cong
tp->root is a void* pointer, no need to cast it. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13net_sched: add struct net pointer to tcf_proto_ops->dumpWANG Cong
It will be needed by the next patch. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18net_sched: cls: refactor out struct tcf_ext_mapWANG Cong
These information can be saved in tcf_exts, and this will simplify the code. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18net_sched: act: use standard struct list_headWANG Cong
Currently actions are chained by a singly linked list, therefore it is a bit hard to add and remove a specific entry. Convert it to struct list_head so that in the latter patch we can remove an action without finding its head. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-14pkt_sched: namespace aware act_mirredBenjamin LaHaise
Eric Dumazet pointed out that act_mirred needs to find the current net_ns, and struct net pointer is not provided in the call chain. His original patch made use of current->nsproxy->net_ns to find the network namespace, but this fails to work correctly for userspace code that makes use of netlink sockets in different network namespaces. Instead, pass the "struct net *" down along the call chain to where it is needed. This version removes the ifb changes as Eric has submitted that patch separately, but is otherwise identical to the previous version. Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-14net sched: Pass the skb into change so it can access NETLINK_CBEric W. Biederman
cls_flow.c plays with uids and gids. Unless I misread that code it is possible for classifiers to depend on the specific uid and gid values. Therefore I need to know the user namespace of the netlink socket that is installing the packet classifiers. Pass in the rtnetlink skb so I can access the NETLINK_CB of the passed packet. In particular I want access to sk_user_ns(NETLINK_CB(in_skb).ssk). Pass in not the user namespace but the incomming rtnetlink skb into the the classifier change routines as that is generally the more useful parameter. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>