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path: root/net/sched/cls_api.c
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2012-11-18net: Push capable(CAP_NET_ADMIN) into the rtnl methodsEric W. Biederman
- In rtnetlink_rcv_msg convert the capable(CAP_NET_ADMIN) check to ns_capable(net->user-ns, CAP_NET_ADMIN). Allowing unprivileged users to make netlink calls to modify their local network namespace. - In the rtnetlink doit methods add capable(CAP_NET_ADMIN) so that calls that are not safe for unprivileged users are still protected. Later patches will remove the extra capable calls from methods that are safe for unprivilged users. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-10netlink: Rename pid to portid to avoid confusionEric W. Biederman
It is a frequent mistake to confuse the netlink port identifier with a process identifier. Try to reduce this confusion by renaming fields that hold port identifiers portid instead of pid. I have carefully avoided changing the structures exported to userspace to avoid changing the userspace API. I have successfully built an allyesconfig kernel with this change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Stephen Hemminger <shemminger@vyatta.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>
2012-06-26pkt_sched: cls_api: Move away from NLMSG_NEW().David S. Miller
And use nlmsg_data() while we're here too, as well as remove a useless cast. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-01pkt_sched: Stop using NLA_PUT*().David S. Miller
These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-06net: sched: constify tcf_proto and tc_actionEric Dumazet
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-09rtnetlink: Compute and store minimum ifinfo dump sizeGreg Rose
The message size allocated for rtnl ifinfo dumps was limited to a single page. This is not enough for additional interface info available with devices that support SR-IOV and caused a bug in which VF info would not be displayed if more than approximately 40 VFs were created per interface. Implement a new function pointer for the rtnl_register service that will calculate the amount of data required for the ifinfo dump and allocate enough data to satisfy the request. Signed-off-by: Greg Rose <gregory.v.rose@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2011-01-19net_sched: cleanupsEric Dumazet
Cleanup net/sched code to current CodingStyle and practices. Reduce inline abuse Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-11Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/stmmac/stmmac_main.c drivers/net/wireless/wl12xx/wl1271_cmd.c drivers/net/wireless/wl12xx/wl1271_main.c drivers/net/wireless/wl12xx/wl1271_spi.c net/core/ethtool.c net/mac80211/scan.c
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-22net_sched: make traffic control network namespace awareTom Goff
Mostly minor changes to add a net argument to various functions and remove initial network namespace checks. Make /proc/net/psched per network namespace. Signed-off-by: Tom Goff <thomas.goff@boeing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-25net: use net_eq to compare netsOctavian Purdila
Generated with the following semantic patch @@ struct net *n1; struct net *n2; @@ - n1 == n2 + net_eq(n1, n2) @@ struct net *n1; struct net *n2; @@ - n1 != n2 + !net_eq(n1, n2) applied over {include,net,drivers/net}. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-05net_cls: Use __dev_get_by_index()Eric Dumazet
We hold RTNL in tc_dump_tfilter(), we can avoid dev_hold()/dev_put() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-08netlink: fix typo in initializationJiri Pirko
Commit 9ef1d4c7c7aca1cd436612b6ca785b726ffb8ed8 ("[NETLINK]: Missing initializations in dumped data") introduced a typo in initialization. This patch fixes this. Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: reintroduce dev->qdisc for use by sch_apiPatrick McHardy
Currently the multiqueue integration with the qdisc API suffers from a few problems: - with multiple queues, all root qdiscs use the same handle. This means they can't be exposed to userspace in a backwards compatible fashion. - all API operations always refer to queue number 0. Newly created qdiscs are automatically shared between all queues, its not possible to address individual queues or restore multiqueue behaviour once a shared qdisc has been attached. - Dumps only contain the root qdisc of queue 0, in case of non-shared qdiscs this means the statistics are incomplete. This patch reintroduces dev->qdisc, which points to the (single) root qdisc from userspace's point of view. Currently it either points to the first (non-shared) default qdisc, or a qdisc shared between all queues. The following patches will introduce a classful dummy qdisc, which will be used as root qdisc and contain the per-queue qdiscs as children. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: make cls_ops->tcf_chain() optionalPatrick McHardy
Some qdiscs don't support attaching filters. Handle this centrally in cls_api and return a proper errno code (EOPNOTSUPP) instead of EINVAL. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-02net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel ↵Minoru Usui
panic when we use cls_cgroup This patch fixes a bug which unconfigured struct tcf_proto keeps chaining in tc_ctl_tfilter(), and avoids kernel panic in cls_cgroup_classify() when we use cls_cgroup. When we execute 'tc filter add', tcf_proto is allocated, initialized by classifier's init(), and chained. After it's chained, tc_ctl_tfilter() calls classifier's change(). When classifier's change() fails, tc_ctl_tfilter() does not free and keeps tcf_proto. In addition, cls_cgroup is initialized in change() not in init(). It accesses unconfigured struct tcf_proto which is chained before change(), then hits Oops. Signed-off-by: Minoru Usui <usui@mxm.nes.nec.co.jp> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca> Tested-by: Minoru Usui <usui@mxm.nes.nec.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-02net: Only store high 16 bits of kernel generated filter prioritiesRobert Love
The kernel should only be using the high 16 bits of a kernel generated priority. Filter priorities in all other cases only use the upper 16 bits of the u32 'prio' field of 'struct tcf_proto', but when the kernel generates the priority of a filter is saves all 32 bits which can result in incorrect lookup failures when a filter needs to be deleted or modified. Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20pkt_sched: remove unnecessary xchg() in packet classifiersPatrick McHardy
The use of xchg() hasn't been necessary since 2.2.something when proper locking was added to packet schedulers. In the case of classifiers they mostly weren't even necessary before that since they're mainly used to assign a NULL pointer to the filter root in the ->destroy path; the root is destroyed immediately after that. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-16net: Remove CONFIG_KMOD from net/ (towards removing CONFIG_KMOD entirely)Johannes Berg
Some code here depends on CONFIG_KMOD to not try to load protocol modules or similar, replace by CONFIG_MODULES where more than just request_module depends on CONFIG_KMOD and and also use try_then_request_module in ebtables. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-29pkt_sched: Fix locking of qdisc_root with qdisc_root_sleeping_lock()Jarek Poplawski
Use qdisc_root_sleeping_lock() instead of qdisc_root_lock() where appropriate. The only difference is while dev is deactivated, when currently we can use a sleeping qdisc with the lock of noop_qdisc. This shouldn't be dangerous since after deactivation root lock could be used only by gen_estimator code, but looks wrong anyway. Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-14pkt_sched: Fix unlocking in tc_ctl_tfilter()Jarek Poplawski
Fix a bug with spin_lock_bh() inserted instead of spin_unlock_bh() by some recent patch. Reported-by: Denys Fedoryshchenko <denys@visp.net.lb> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17pkt_sched: Remove qdisc_lock_tree usage in cls_api.cDavid S. Miller
It just wants the qdisc tree for the filter to be synchronized. So just BH lock qdisc_root_lock(q) instead. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17netdev: Allocate multiple queues for TX.David S. Miller
alloc_netdev_mq() now allocates an array of netdev_queue structures for TX, based upon the queue_count argument. Furthermore, all accesses to the TX queues are now vectored through the netdev_get_tx_queue() and netdev_for_each_tx_queue() interfaces. This makes it easy to grep the tree for all things that want to get to a TX queue of a net device. Problem spots which are not really multiqueue aware yet, and only work with one queue, can easily be spotted by grepping for all netdev_get_tx_queue() calls that pass in a zero index. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08netdev: Move rest of qdisc state into struct netdev_queueDavid S. Miller
Now qdisc, qdisc_sleeping, and qdisc_list also live there. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-08pkt_sched: Remove 'dev' member of struct Qdisc.David S. Miller
It can be obtained via the netdev_queue. So create a helper routine, qdisc_dev(), to make the transformations nicer looking. Now, qdisc_alloc() now no longer needs a net_device pointer argument. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-20net_sched: cls_api: fix return value for non-existant classifiersPatrick McHardy
cls_api should return ENOENT when the requested classifier doesn't exist. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.YOSHIFUJI Hideaki
Introduce per-sock inlines: sock_net(), sock_net_set() and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set(). Without CONFIG_NET_NS, no namespace other than &init_net exists. Let's explicitly define them to help compiler optimizations. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-01-31[NET_SCHED]: Constify struct tcf_ext_mapPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Use NLA_PUT_STRING for string dumpingPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Use nla_nest_start/nla_nest_endPatrick McHardy
Use nla_nest_start/nla_nest_end for dumping nested attributes. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: act_api: use PTR_ERR in tcf_action_init/tcf_action_getPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Convert actions from rtnetlink to new netlink APIPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: Convert classifiers from rtnetlink to new netlink APIPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET_SCHED]: mark classifier ops __read_mostlyPatrick McHardy
Additionally remove unnecessary NULL initilizations of the next pointer. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[PKT_SCHED] net classifier: style cleanup'sStephen Hemminger
Classifier code cleanup. Get rid of printk wrapper, and fix whitespace and other style stuff reported by checkpatch Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Make rtnetlink infrastructure network namespace aware (v3)Denis V. Lunev
After this patch none of the netlink callback support anything except the initial network namespace but the rtnetlink infrastructure now handles multiple network namespaces. Changes from v2: - IPv6 addrlabel processing Changes from v1: - no need for special rtnl_unlock handling - fixed IPv6 ndisc Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Modify all rtnetlink methods to only work in the initial namespace (v2)Denis V. Lunev
Before I can enable rtnetlink to work in all network namespaces I need to be certain that something won't break. So this patch deliberately disables all of the rtnletlink methods in everything except the initial network namespace. After the methods have been audited this extra check can be disabled. Changes from v1: - added IPv6 addrlabel protection Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-28[NET]: Move Qdisc_class_ops and Qdisc_ops in appropriate sections.Eric Dumazet
Qdisc_class_ops are const, and Qdisc_ops are mostly read. Using "const" and "__read_mostly" qualifiers helps to reduce false sharing. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make the device list and device lookups per namespace.Eric W. Biederman
This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-15[NET_SCHED]: Kill CONFIG_NET_CLS_POLICEPatrick McHardy
The NET_CLS_ACT option is now a full replacement for NET_CLS_POLICE, remove the old code. The config option will be kept around to select the equivalent NET_CLS_ACT options for a short time to allow easier upgrades. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10[NET_SCHED]: Remove unnecessary includesPatrick McHardy
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NET_SCHED]: Eliminate qdisc_tree_lockPatrick McHardy
Since we're now holding the rtnl during the entire dump operation, we can remove qdisc_tree_lock, whose only purpose is to protect dump callbacks from concurrent changes to the qdisc tree. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[PKT_SCHED] cls: Use rtnl registration interfaceThomas Graf
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Use nlmsg_trim() where appropriateArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Convert skb->tail to sk_buff_data_tArnaldo Carvalho de Melo
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-14[PATCH] remove many unneeded #includes of sched.hTim Schmielau
After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10[NET] SCHED: Fix whitespace errors.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[SCHED]: Use kmemdup & kzalloc where appropriateArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-09-28[NET_SCHED]: Fix fallout from dev->qdisc RCU changePatrick McHardy
The move of qdisc destruction to a rcu callback broke locking in the entire qdisc layer by invalidating previously valid assumptions about the context in which changes to the qdisc tree occur. The two assumptions were: - since changes only happen in process context, read_lock doesn't need bottem half protection. Now invalid since destruction of inner qdiscs, classifiers, actions and estimators happens in the RCU callback unless they're manually deleted, resulting in dead-locks when read_lock in process context is interrupted by write_lock_bh in bottem half context. - since changes only happen under the RTNL, no additional locking is necessary for data not used during packet processing (f.e. u32_list). Again, since destruction now happens in the RCU callback, this assumption is not valid anymore, causing races while using this data, which can result in corruption or use-after-free. Instead of "fixing" this by disabling bottem halfs everywhere and adding new locks/refcounting, this patch makes these assumptions valid again by moving destruction back to process context. Since only the dev->qdisc pointer is protected by RCU, but ->enqueue and the qdisc tree are still protected by dev->qdisc_lock, destruction of the tree can be performed immediately and only the final free needs to happen in the rcu callback to make sure dev_queue_xmit doesn't access already freed memory. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>