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2017-05-25net_sched: only create filter chains for new filters/actionsWANG Cong1-4/+9
tcf_chain_get() always creates a new filter chain if not found in existing ones. This is totally unnecessary when we get or delete filters, new chain should be only created for new filters (or new actions). Fixes: 5bc1701881e3 ("net: sched: introduce multichain support for filters") Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-25net: sched: cls_api: make reclassify return all the way back to the original tpJiri Pirko1-3/+5
With the introduction of chain goto action, the reclassification would cause the re-iteration of the actual chain. It makes more sense to restart the whole thing and re-iterate starting from the original tp - start of chain 0. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-23net/sched: fix filter flushingJiri Pirko1-3/+10
When user instructs to remove all filters from chain, we cannot destroy the chain as other actions may hold a reference. Also the put in errout would try to destroy it again. So instead, just walk the chain and remove all existing filters. Fixes: 5bc1701881e3 ("net: sched: introduce multichain support for filters") Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-23net/sched: properly assign RCU pointer in tcf_chain_tp_insert/removeJiri Pirko1-2/+2
*p_filter_chain is rcu-dereferenced on reader path. So here in writer, property assign the pointer. Fixes: 2190d1d0944f ("net: sched: introduce helpers to work with filter chains") Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: add termination action to allow goto chainJiri Pirko1-1/+5
Introduce new type of termination action called "goto_chain". This allows user to specify a chain to be processed. This action type is then processed as a return value in tcf_classify loop in similar way as "reclassify" is, only it does not reset to the first filter in chain but rather reset to the first filter of the desired chain. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: push tp down to action initJiri Pirko1-4/+5
Tp pointer will be needed by the next patch in order to get the chain. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: introduce multichain support for filtersJiri Pirko1-16/+88
Instead of having only one filter per block, introduce a list of chains for every block. Create chain 0 by default. UAPI is extended so the user can specify which chain he wants to change. If the new attribute is not specified, chain 0 is used. That allows to maintain backward compatibility. If chain does not exist and user wants to manipulate with it, new chain is created with specified index. Also, when last filter is removed from the chain, the chain is destroyed. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: push chain dump to a separate functionJiri Pirko1-43/+52
Since there will be multiple chains to dump, push chain dumping code to a separate function. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: introduce helpers to work with filter chainsJiri Pirko1-41/+107
Introduce struct tcf_chain object and set of helpers around it. Wraps up insertion, deletion and search in the filter chain. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: move TC_H_MAJ macro call into tcf_auto_prioJiri Pirko1-2/+2
Call the helper from the function rather than to always adjust the return value of the function. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: replace nprio by a bool to make the function more readableJiri Pirko1-6/+7
The use of "nprio" variable in tc_ctl_tfilter is a bit cryptic and makes a reader wonder what is going on for a while. So help him to understand this priority allocation dance a litte bit better. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: rename tcf_destroy_chain helperJiri Pirko1-3/+3
Make the name consistent with the rest of the helpers around. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: introduce tcf block infractructureJiri Pirko1-10/+38
Currently, the filter chains are direcly put into the private structures of qdiscs. In order to be able to have multiple chains per qdisc and to allow filter chains sharing among qdiscs, there is a need for common object that would hold the chains. This introduces such object and calls it "tcf_block". Helpers to get and put the blocks are provided to be called from individual qdisc code. Also, the original filter_list pointers are left in qdisc privs to allow the entry into tcf_block processing without any added overhead of possible multiple pointer dereference on fast path. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: move tc_classify function to cls_api.cJiri Pirko1-0/+48
Move tc_classify function to cls_api.c where it belongs, rename it to fit the namespace. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21net_sched: move the empty tp check from ->destroy() to ->delete()WANG Cong1-13/+14
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>
2017-04-17net: rtnetlink: plumb extended ack to doit functionDavid Ahern1-2/+3
Add netlink_ext_ack arg to rtnl_doit_func. Pass extack arg to nlmsg_parse for doit functions that call it directly. This is the first step to using extended error reporting in rtnetlink. >From here individual subsystems can be updated to set netlink_ext_ack as needed. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg1-1/+1
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>
2017-02-14sched: Fix accidental removal of errout gotoJiri Pirko1-0/+1
Bring back the goto that was removed by accident. Reported-by: Colin Ian King <colin.king@canonical.com> Fixes: 40c81b25b16c ("sched: check negative err value to safe one level of indent") Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: check negative err value to safe one level of indentJiri Pirko1-13/+9
As it is more common, check err for !0. That allows to safe one level of indentation and makes the code easier to read. Also, make 'next' variable global in function as it is used twice. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: add missing curly braces in else branch in tc_ctl_tfilterJiri Pirko1-1/+2
Curly braces need to be there, for stylistic reasons. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: move err set right before goto errout in tc_ctl_tfilterJiri Pirko1-10/+19
This makes the reader to know right away what is the error value. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: push TC filter protocol creation into a separate functionJiri Pirko1-51/+59
Make the long function tc_ctl_tfilter a little bit shorter and easier to read. Also make the creation of filter proto symmetric to destruction. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_apiJiri Pirko1-0/+21
Creation is done in this file, move destruction to be at the same place. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: rename tcf_destroy to tcf_destroy_protoJiri Pirko1-4/+4
This function destroys TC filter protocol, not TC filter. So name it accordingly. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-26net, sched: fix soft lockup in tc_classifyDaniel Borkmann1-1/+3
Shahar reported a soft lockup in tc_classify(), where we run into an endless loop when walking the classifier chain due to tp->next == tp which is a state we should never run into. The issue only seems to trigger under load in the tc control path. What happens is that in tc_ctl_tfilter(), thread A allocates a new tp, initializes it, sets tp_created to 1, and calls into tp->ops->change() with it. In that classifier callback we had to unlock/lock the rtnl mutex and returned with -EAGAIN. One reason why we need to drop there is, for example, that we need to request an action module to be loaded. This happens via tcf_exts_validate() -> tcf_action_init/_1() meaning after we loaded and found the requested action, we need to redo the whole request so we don't race against others. While we had to unlock rtnl in that time, thread B's request was processed next on that CPU. Thread B added a new tp instance successfully to the classifier chain. When thread A returned grabbing the rtnl mutex again, propagating -EAGAIN and destroying its tp instance which never got linked, we goto replay and redo A's request. This time when walking the classifier chain in tc_ctl_tfilter() for checking for existing tp instances we had a priority match and found the tp instance that was created and linked by thread B. Now calling again into tp->ops->change() with that tp was successful and returned without error. tp_created was never cleared in the second round, thus kernel thinks that we need to link it into the classifier chain (once again). tp and *back point to the same object due to the match we had earlier on. Thus for thread B's already public tp, we reset tp->next to tp itself and link it into the chain, which eventually causes the mentioned endless loop in tc_classify() once a packet hits the data path. Fix is to clear tp_created at the beginning of each request, also when we replay it. On the paths that can cause -EAGAIN we already destroy the original tp instance we had and on replay we really need to start from scratch. It seems that this issue was first introduced in commit 12186be7d2e1 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup"). Fixes: 12186be7d2e1 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup") Reported-by: Shahar Klein <shahark@mellanox.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Tested-by: Shahar Klein <shahark@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02net/sched: cls_flower: Add offload support using egress Hardware deviceHadar Hen Zion1-0/+24
In order to support hardware offloading when the device given by the tc rule is different from the Hardware underline device, extract the mirred (egress) device from the tc action when a filter is added, using the new tc_action_ops, get_dev(). Flower caches the information about the mirred device and use it for calling ndo_setup_tc in filter change, update stats and delete. Calling ndo_setup_tc of the mirred (egress) device instead of the ingress device will allow a resolution between the software ingress device and the underline hardware device. The resolution will take place inside the offloading driver using 'egress_device' flag added to tc_to_netdev struct which is provided to the offloading driver. Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25net sched filters: fix filter handle ID in tfilter_notify_chain()Roman Mashak1-1/+1
Should pass valid filter handle, not the netlink flags. Fixes: 30a391a13ab92 ("net sched filters: pass netlink message flags in event notification") Signed-off-by: Roman Mashak <mrv@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Reported-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-17net sched filters: pass netlink message flags in event notificationRoman Mashak1-2/+3
Userland client should be able to read an event, and reflect it back to the kernel, therefore it needs to extract complete set of netlink flags. For example, this will allow "tc monitor" to distinguish Add and Replace operations. Signed-off-by: Roman Mashak <mrv@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-28net sched filters: fix notification of filter delete with proper handleJamal Hadi Salim1-1/+2
Daniel says: While trying out [1][2], I noticed that tc monitor doesn't show the correct handle on delete: $ tc monitor qdisc clsact ffff: dev eno1 parent ffff:fff1 filter dev eno1 ingress protocol all pref 49152 bpf handle 0x2a [...] deleted filter dev eno1 ingress protocol all pref 49152 bpf handle 0xf3be0c80 some context to explain the above: The user identity of any tc filter is represented by a 32-bit identifier encoded in tcm->tcm_handle. Example 0x2a in the bpf filter above. A user wishing to delete, get or even modify a specific filter uses this handle to reference it. Every classifier is free to provide its own semantics for the 32 bit handle. Example: classifiers like u32 use schemes like 800:1:801 to describe the semantics of their filters represented as hash table, bucket and node ids etc. Classifiers also have internal per-filter representation which is different from this externally visible identity. Most classifiers set this internal representation to be a pointer address (which allows fast retrieval of said filters in their implementations). This internal representation is referenced with the "fh" variable in the kernel control code. When a user successfuly deletes a specific filter, by specifying the correct tcm->tcm_handle, an event is generated to user space which indicates which specific filter was deleted. Before this patch, the "fh" value was sent to user space as the identity. As an example what is shown in the sample bpf filter delete event above is 0xf3be0c80. This is infact a 32-bit truncation of 0xffff8807f3be0c80 which happens to be a 64-bit memory address of the internal filter representation (address of the corresponding filter's struct cls_bpf_prog); After this patch the appropriate user identifiable handle as encoded in the originating request tcm->tcm_handle is generated in the event. One of the cardinal rules of netlink rules is to be able to take an event (such as a delete in this case) and reflect it back to the kernel and successfully delete the filter. This patch achieves that. Note, this issue has existed since the original TC action infrastructure code patch back in 2004 as found in: https://git.kernel.org/cgit/linux/kernel/git/history/history.git/commit/ [1] http://patchwork.ozlabs.org/patch/682828/ [2] http://patchwork.ozlabs.org/patch/682829/ Fixes: 4e54c4816bfe ("[NET]: Add tc extensions infrastructure.") Reported-by: Daniel Borkmann <daniel@iogearbox.net> Acked-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>
2016-10-13net_sched: do not broadcast RTM_GETTFILTER resultEric Dumazet1-7/+11
There are two ways to get tc filters from kernel to user space. 1) Full dump (tc_dump_tfilter()) 2) RTM_GETTFILTER to get one precise filter, reducing overhead. The second operation is unfortunately broadcasting its result, polluting "tc monitor" users. This patch makes sure only the requester gets the result, using netlink_unicast() instead of rtnetlink_send() Jamal cooked an iproute2 patch to implement "tc filter get" operation, but other user space libraries already use RTM_GETTFILTER when a single filter is queried, instead of dumping all filters. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-20net sched: stylistic cleanupsJamal Hadi Salim1-8/+10
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18net_sched: convert tcf_exts from list to pointer arrayWANG Cong1-15/+36
As pointed out by Jamal, an action could be shared by multiple filters, so we can't use list to chain them any more after we get rid of the original tc_action. Instead, we could just save pointers to these actions in tcf_exts, since they are refcount'ed, so convert the list to an array of pointers. The "ugly" part is the action API still accepts list as a parameter, I just introduce a helper function to convert the array of pointers to a list, instead of relying on the C99 feature to iterate the array. Fixes: a85a970af265 ("net_sched: move tc_action into tcf_common") Reported-by: Jamal Hadi Salim <jhs@mojatatu.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>
2016-06-17net, cls: also reject deleting all filters when TCA_KIND presentDaniel Borkmann1-1/+1
When we check for RTM_DELTFILTER, we should also reject the request for deleting all filters under a given parent when TCA_KIND attribute is present. If present, it's currently just ignored but there's also no point to let it pass in the first place either since this doesn't have any meaning with wild-card removal. Fixes: ea7f8277f907 ("net, cls: allow for deleting all filters for given parent") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-11net, cls: allow for deleting all filters for given parentDaniel Borkmann1-4/+33
Add a possibility where the user can just specify the parent and all filters under that parent are then being purged. Currently, for example for scripting, one needs to specify pref/prio to have a well-defined number for 'tc filter del' command for addressing the previously created instance or additionally filter handle in case of priorities being the same. Improve usage by allowing the option for tc to specify the parent and removing the whole chain for that given parent. Example usage after patch, no tc changes required: # tc qdisc replace dev foo clsact # tc filter add dev foo egress bpf da obj ./bpf.o # tc filter add dev foo egress bpf da obj ./bpf.o # tc filter show dev foo egress filter protocol all pref 49151 bpf filter protocol all pref 49151 bpf handle 0x1 bpf.o:[classifier] direct-action filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 bpf.o:[classifier] direct-action # tc filter del dev foo egress # tc filter show dev foo egress # Previously, RTM_DELTFILTER requests with invalid prio of 0 were rejected, so only netlink requests with RTM_NEWTFILTER and NLM_F_CREATE flag were allowed where the kernel would auto-generate a pref/prio. We can piggyback on that and use prio of 0 as a wildcard for requests of RTM_DELTFILTER. For notifying tc netlink monitoring users (e.g. libnl uses this for caching), there are two options, that is, sending individual tfilter_notify() notifications for each tcf_proto, or sending a single one indicating wildcard removal. I tried both and there are pros and cons for each, eventually I decided for sending individual tfilter_notify(), so that user space can support this seamlessly and there won't be a mess of changing each and every application to make sure expectations from the kernel won't break when they don't understand single notification. Since linear chains don't really scale, I expect only a handful of classifiers to be attached at max for a given parent anyway. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08net sched: indentation and other OCD stylistic fixesJamal Hadi Salim1-4/+7
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
2015-05-22net: sched: fix call_rcu() race on classifier module unloadsDaniel Borkmann1-0/+5
Vijay reported that a loop as simple as ... while true; do tc qdisc add dev foo root handle 1: prio tc filter add dev foo parent 1: u32 match u32 0 0 flowid 1 tc qdisc del dev foo root rmmod cls_u32 done ... will panic the kernel. Moreover, he bisected the change apparently introducing it to 78fd1d0ab072 ("netlink: Re-add locking to netlink_lookup() and seq walker"). The removal of synchronize_net() from the netlink socket triggering the qdisc to be removed, seems to have uncovered an RCU resp. module reference count race from the tc API. Given that RCU conversion was done after e341694e3eb5 ("netlink: Convert netlink_lookup() to use RCU protected hash table") which added the synchronize_net() originally, occasion of hitting the bug was less likely (not impossible though): When qdiscs that i) support attaching classifiers and, ii) have at least one of them attached, get deleted, they invoke tcf_destroy_chain(), and thus call into ->destroy() handler from a classifier module. After RCU conversion, all classifier that have an internal prio list, unlink them and initiate freeing via call_rcu() deferral. Meanhile, tcf_destroy() releases already reference to the tp->ops->owner module before the queued RCU callback handler has been invoked. Subsequent rmmod on the classifier module is then not prevented since all module references are already dropped. By the time, the kernel invokes the RCU callback handler from the module, that function address is then invalid. One way to fix it would be to add an rcu_barrier() to unregister_tcf_proto_ops() to wait for all pending call_rcu()s to complete. synchronize_rcu() is not appropriate as under heavy RCU callback load, registered call_rcu()s could be deferred longer than a grace period. In case we don't have any pending call_rcu()s, the barrier is allowed to return immediately. Since we came here via unregister_tcf_proto_ops(), there are no users of a given classifier anymore. Further nested call_rcu()s pointing into the module space are not being done anywhere. Only cls_bpf_delete_prog() may schedule a work item, to unlock pages eventually, but that is not in the range/context of cls_bpf anymore. Fixes: 25d8c0d55f24 ("net: rcu-ify tcf_proto") Fixes: 9888faefe132 ("net: sched: cls_basic use RCU") Reported-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Thomas Graf <tgraf@suug.ch> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09net_sched: fix a use-after-free in tc_ctl_tfilter()WANG Cong1-4/+3
When tcf_destroy() returns true, tp could be already destroyed, we should not use tp->next after that. For long term, we probably should move tp list to list_head. Fixes: 1e052be69d04 ("net_sched: destroy proto tp when all filters are gone") 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>
2015-03-09net_sched: destroy proto tp when all filters are goneCong Wang1-4/+10
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>
2015-02-05cls_api.c: Fix dumping of non-existing actions' stats.Ignacy Gawędzki1-3/+4
In tcf_exts_dump_stats(), ensure that exts->actions is not empty before accessing the first element of that list and calling tcf_action_copy_stats() on it. This fixes some random segvs when adding filters of type "basic" with no particular action. This also fixes the dumping of those "no-action" filters, which more often than not made calls to tcf_action_copy_stats() fail and consequently netlink attributes added by the caller to be removed by a call to nla_nest_cancel(). Fixes: 33be62715991 ("net_sched: act: use standard struct list_head") Signed-off-by: Ignacy Gawędzki <ignacy.gawedzki@green-communications.fr> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
2014-10-08net_sched: copy exts->type in tcf_exts_change()WANG Cong1-0/+1
We need to copy exts->type when committing the change, otherwise it would be always 0. This is a quick fix for -net and -stable, for net-next tcf_exts will be removed. Fixes: commit 33be627159913b094bb578e83 ("net_sched: act: use standard struct list_head") Reported-by: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: John Fastabend <john.fastabend@gmail.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>
2014-09-29net_sched: remove the first parameter from tcf_exts_destroy()WANG Cong1-1/+1
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: rcu-ify tcf_protoJohn Fastabend1-15/+15
rcu'ify tcf_proto this allows calling tc_classify() without holding any locks. Updaters are protected by RTNL. This patch prepares the core net_sched infrastracture for running the classifier/action chains without holding the qdisc lock however it does nothing to ensure cls_xxx and act_xxx types also work without locking. Additional patches are required to address the fall out. 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>
2014-07-18net_sched: cancel nest attribute on failure in tcf_exts_dump()Cong Wang1-3/+8
Like other places, we need to cancel the nest attribute after we start. Fortunately the netlink message will not be sent on failure, so it's not a big problem at all. 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>
2014-05-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Conflicts: drivers/net/ethernet/altera/altera_sgdma.c net/netlink/af_netlink.c net/sched/cls_api.c net/sched/sch_api.c The netlink conflict dealt with moving to netlink_capable() and netlink_ns_capable() in the 'net' tree vs. supporting 'tc' operations in non-init namespaces. These were simple transformations from netlink_capable to netlink_ns_capable. The Altera driver conflict was simply code removal overlapping some void pointer cast cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-03net: Allow tc changes in user namespacesStéphane Graber1-1/+2
This switches a few remaining capable(CAP_NET_ADMIN) to ns_capable so that root in a user namespace may set tc rules inside that namespace. Signed-off-by: Stéphane Graber <stgraber@ubuntu.com> Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-28sched, act: allow to clear all actions as wellCong Wang1-8/+6
When we change the list of action on a given filter, currently we don't change it to empty. This is a bug, we should allow to change to whatever users given. 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>
2014-04-28sched, cls: check if we could overwrite actions when changing a filterCong Wang1-4/+5
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>
2014-04-24net: Use netlink_ns_capable to verify the permisions of netlink messagesEric W. Biederman1-1/+1
It is possible by passing a netlink socket to a more privileged executable and then to fool that executable into writing to the socket data that happens to be valid netlink message to do something that privileged executable did not intend to do. To keep this from happening replace bare capable and ns_capable calls with netlink_capable, netlink_net_calls and netlink_ns_capable calls. Which act the same as the previous calls except they verify that the opener of the socket had the desired permissions as well. Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13net_sched: add struct net pointer to tcf_proto_ops->dumpWANG Cong1-5/+6
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>