kernel.git/net/sched/act_api.c, branch linux-4.15.y

net sched actions: fix dumping which requires several messages to user space

2018-04-12T10:31:16Z

[ Upstream commit 734549eb550c0c720bc89e50501f1b1e98cdd841 ] Fixes a bug in the tcf_dump_walker function that can cause some actions to not be reported when dumping a large number of actions. This issue became more aggrevated when cookies feature was added. In particular this issue is manifest when large cookie values are assigned to the actions and when enough actions are created that the resulting table must be dumped in multiple batches. The number of actions returned in each batch is limited by the total number of actions and the memory buffer size. With small cookies the numeric limit is reached before the buffer size limit, which avoids the code path triggering this bug. When large cookies are used buffer fills before the numeric limit, and the erroneous code path is hit. For example after creating 32 csum actions with the cookie aaaabbbbccccdddd $ tc actions ls action csum total acts 26 action order 0: csum (tcp) action continue index 1 ref 1 bind 0 cookie aaaabbbbccccdddd ..... action order 25: csum (tcp) action continue index 26 ref 1 bind 0 cookie aaaabbbbccccdddd total acts 6 action order 0: csum (tcp) action continue index 28 ref 1 bind 0 cookie aaaabbbbccccdddd ...... action order 5: csum (tcp) action continue index 32 ref 1 bind 0 cookie aaaabbbbccccdddd Note that the action with index 27 is omitted from the report. Fixes: 4b3550ef530c ("[NET_SCHED]: Use nla_nest_start/nla_nest_end")" Signed-off-by: Craig Dillabaugh Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-10T01:00:18Z

Simple cases of overlapping changes in the packet scheduler. Must easier to resolve this time. Which probably means that I screwed it up somehow. Signed-off-by: David S. Miller

Revert "net_sched: hold netns refcnt for each action"

2017-11-09T01:03:09Z

This reverts commit ceffcc5e254b450e6159f173e4538215cebf1b59. If we hold that refcnt, the netns can never be destroyed until all actions are destroyed by user, this breaks our netns design which we expect all actions are destroyed when we destroy the whole netns. Cc: Lucas Bates Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-04T00:26:51Z

Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller

net_sched: hold netns refcnt for each action

2017-11-03T01:30:38Z

TC actions have been destroyed asynchronously for a long time, previously in a RCU callback and now in a workqueue. If we don't hold a refcnt for its netns, we could use the per netns data structure, struct tcf_idrinfo, after it has been freed by netns workqueue. Hold refcnt to ensure netns destroy happens after all actions are gone. Fixes: ddf97ccdd7cb ("net_sched: add network namespace support for tc actions") Reported-by: Lucas Bates Tested-by: Lucas Bates Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net_sched: acquire RTNL in tc_action_net_exit()

2017-11-03T01:30:38Z

I forgot to acquire RTNL in tc_action_net_exit() which leads that action ops->cleanup() is not always called with RTNL. This usually is not a big deal because this function is called after all netns refcnt are gone, but given RTNL protects more than just actions, add it for safety and consistency. Also add an assertion to catch other potential bugs. Fixes: ddf97ccdd7cb ("net_sched: add network namespace support for tc actions") Reported-by: Lucas Bates Tested-by: Lucas Bates Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net/sched: Set the net-device for egress device instance

2017-10-20T12:09:35Z

Currently the netdevice field is not set and the egdev instance is not functional, fix that. Fixes: 3f55bdda8df ('net: sched: introduce per-egress action device callbacks') Signed-off-by: Or Gerlitz Acked-by: Jiri Pirko Signed-off-by: David S. Miller

net: sched: introduce per-egress action device callbacks

2017-10-12T03:15:43Z

Introduce infrastructure that allows drivers to register callbacks that are called whenever tc would offload inserted rule and specified device acts as tc action egress device. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

net: sched: fix use-after-free in tcf_action_destroy and tcf_del_walker

2017-09-13T16:34:08Z

Recent commit d7fb60b9cafb ("net_sched: get rid of tcfa_rcu") removed freeing in call_rcu, which changed already existing hard-to-hit race condition into 100% hit: [ 598.599825] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030 [ 598.607782] IP: tcf_action_destroy+0xc0/0x140 Or: [ 40.858924] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030 [ 40.862840] IP: tcf_generic_walker+0x534/0x820 Fix this by storing the ops and use them directly for module_put call. Fixes: a85a970af265 ("net_sched: move tc_action into tcf_common") Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

net_sched: get rid of tcfa_rcu

2017-09-13T03:41:02Z

gen estimator has been rewritten in commit 1c0d32fde5bd ("net_sched: gen_estimator: complete rewrite of rate estimators"), the caller is no longer needed to wait for a grace period. So this patch gets rid of it. This also completely closes a race condition between action free path and filter chain add/remove path for the following patch. Because otherwise the nested RCU callback can't be caught by rcu_barrier(). Please see also the comments in code. Cc: Jiri Pirko Cc: Jamal Hadi Salim Cc: Eric Dumazet Signed-off-by: Cong Wang Signed-off-by: David S. Miller