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2011-06-24Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem Conflicts: drivers/net/wireless/rtlwifi/pci.c include/linux/netlink.h
2011-06-22netlink: advertise incomplete dumpsJohannes Berg
Consider the following situation: * a dump that would show 8 entries, four in the first round, and four in the second * between the first and second rounds, 6 entries are removed * now the second round will not show any entry, and even if there is a sequence/generation counter the application will not know To solve this problem, add a new flag NLM_F_DUMP_INTR to the netlink header that indicates the dump wasn't consistent, this flag can also be set on the MSG_DONE message that terminates the dump, and as such above situation can be detected. To achieve this, add a sequence counter to the netlink callback struct. Of course, netlink code still needs to use this new functionality. The correct way to do that is to always set cb->seq when a dumpit callback is invoked and call nl_dump_check_consistent() for each new message. The core code will also call this function for the final MSG_DONE message. To make it usable with generic netlink, a new function genlmsg_nlhdr() is needed to obtain the netlink header from the genetlink user header. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-06-16rtnetlink: unlock on error path in netlink_dump()Dan Carpenter
In c7ac8679bec939 "rtnetlink: Compute and store minimum ifinfo dump size", we moved the allocation under the lock so we need to unlock on error path. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: David S. Miller <davem@conan.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>
2011-05-24net: convert %p usage to %pKDan Rosenberg
The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". The supporting code for kptr_restrict and %pK are currently in the -mm tree. This patch converts users of %p in net/ to %pK. Cases of printing pointers to the syslog are not covered, since this would eliminate useful information for postmortem debugging and the reading of the syslog is already optionally protected by the dmesg_restrict sysctl. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-07net,rcu: convert call_rcu(listeners_free_rcu) to kfree_rcu()Lai Jiangshan
The rcu callback listeners_free_rcu() just calls a kfree(), so we use kfree_rcu() instead of the call_rcu(listeners_free_rcu). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-03-03Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/bnx2x/bnx2x.h
2011-03-03netlink: kill eff_cap from struct netlink_skb_parmsPatrick McHardy
Netlink message processing in the kernel is synchronous these days, capabilities can be checked directly in security_netlink_recv() from the current process. Signed-off-by: Patrick McHardy <kaber@trash.net> Reviewed-by: James Morris <jmorris@namei.org> [chrisw: update to include pohmelfs and uvesafb] Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-03netlink: kill loginuid/sessionid/sid members from struct netlink_skb_parmsPatrick McHardy
Netlink message processing in the kernel is synchronous these days, the session information can be collected when needed. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-28netlink: handle errors from netlink_dump()Andrey Vagin
netlink_dump() may failed, but nobody handle its error. It generates output data, when a previous portion has been returned to user space. This mechanism works when all data isn't go in skb. If we enter in netlink_recvmsg() and skb is absent in the recv queue, the netlink_dump() will not been executed. So if netlink_dump() is failed one time, the new data never appear and the reader will sleep forever. netlink_dump() is called from two places: 1. from netlink_sendmsg->...->netlink_dump_start(). In this place we can report error directly and it will be returned by sendmsg(). 2. from netlink_recvmsg There we can't report error directly, because we have a portion of valid output data and call netlink_dump() for prepare the next portion. If netlink_dump() is failed, the socket will be mark as error and the next recvmsg will be failed. Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-24netlink: fix netlink_change_ngroups()Eric Dumazet
commit 6c04bb18ddd633 (netlink: use call_rcu for netlink_change_ngroups) used a somewhat convoluted and racy way to perform call_rcu(). The old block of memory is freed after a grace period, but the rcu_head used to track it is located in new block. This can clash if we call two times or more netlink_change_ngroups(), and a block is freed before another. call_rcu() called on different cpus makes no guarantee in order of callbacks. Fix this using a more standard way of handling this : Each block of memory contains its own rcu_head, so that no 'use after free' can happens. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Johannes Berg <johannes@sipsolutions.net> CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-31netlink: Make NETLINK_USERSOCK work again.David S. Miller
Once we started enforcing the a nl_table[] entry exist for a protocol, NETLINK_USERSOCK stopped working. Add a dummy table entry so that it works again. Reported-by: Thomas Voegtle <tv@lio96.de> Tested-by: Thomas Voegtle <tv@lio96.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-18netlink: fix compat recvmsgJohannes Berg
Since commit 1dacc76d0014a034b8aca14237c127d7c19d7726 Author: Johannes Berg <johannes@sipsolutions.net> Date: Wed Jul 1 11:26:02 2009 +0000 net/compat/wext: send different messages to compat tasks we had a race condition when setting and then restoring frag_list. Eric attempted to fix it, but the fix created even worse problems. However, the original motivation I had when I added the code that turned out to be racy is no longer clear to me, since we only copy up to skb->len to userspace, which doesn't include the frag_list length. As a result, not doing any frag_list clearing and restoring avoids the race condition, while not introducing any other problems. Additionally, while preparing this patch I found that since none of the remaining netlink code is really aware of the frag_list, we need to use the original skb's information for packet information and credentials. This fixes, for example, the group information received by compat tasks. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: stable@kernel.org [2.6.31+, for 2.6.35 revert 1235f504aa] Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-15Revert "netlink: netlink_recvmsg() fix"David S. Miller
This reverts commit 1235f504aaba2ebeabc863fdb3ceac764a317d47. It causes regressions worse than the problem it was trying to fix. Eric will try to solve the problem another way. Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-26netlink: netlink_recvmsg() fixEric Dumazet
commit 1dacc76d0014 (net/compat/wext: send different messages to compat tasks) introduced a race condition on netlink, in case MSG_PEEK is used. An skb given by skb_recv_datagram() might be shared, we must copy it before any modification, or risk fatal corruption. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-20drop_monitor: convert some kfree_skb call sites to consume_skbNeil Horman
Convert a few calls from kfree_skb to consume_skb Noticed while I was working on dropwatch that I was detecting lots of internal skb drops in several places. While some are legitimate, several were not, freeing skbs that were at the end of their life, rather than being discarded due to an error. This patch converts those calls sites from using kfree_skb to consume_skb, which quiets the in-kernel drop_monitor code from detecting them as drops. Tested successfully by myself Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-16af_netlink: Add needed scm_destroy after scm_send.Eric W. Biederman
scm_send occasionally allocates state in the scm_cookie, so I have modified netlink_sendmsg to guarantee that when scm_send succeeds scm_destory will be called to free that state. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Reviewed-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-21netlink: Implment netlink_broadcast_filteredEric W. Biederman
When netlink sockets are used to convey data that is in a namespace we need a way to select a subset of the listening sockets to deliver the packet to. For the network namespace we have been doing this by only transmitting packets in the correct network namespace. For data belonging to other namespaces netlink_bradcast_filtered provides a mechanism that allows us to examine the destination socket and to decide if we should transmit the specified packet to it. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-06Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/bonding/bond_main.c drivers/net/via-velocity.c drivers/net/wireless/iwlwifi/iwl-agn.c
2010-04-01net: check the length of the socket address passed to connect(2)Changli Gao
check the length of the socket address passed to connect(2). Check the length of the socket address passed to connect(2). If the length is invalid, -EINVAL will be returned. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- net/bluetooth/l2cap.c | 3 ++- net/bluetooth/rfcomm/sock.c | 3 ++- net/bluetooth/sco.c | 3 ++- net/can/bcm.c | 3 +++ net/ieee802154/af_ieee802154.c | 3 +++ net/ipv4/af_inet.c | 5 +++++ net/netlink/af_netlink.c | 3 +++ 7 files changed, 20 insertions(+), 3 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-26netlink: use the appropriate namespace pidTom Goff
This was included in OpenVZ kernels but wasn't integrated upstream. >From git://git.openvz.org/pub/linux-2.6.24-openvz: commit 5c69402f18adf7276352e051ece2cf31feefab02 Author: Alexey Dobriyan <adobriyan@openvz.org> Date: Mon Dec 24 14:37:45 2007 +0300 netlink: fixup ->tgid to work in multiple PID namespaces Signed-off-by: Tom Goff <thomas.goff@boeing.com> Acked-by: Alexey Dobriyan <adobriyan@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-20netlink: fix NETLINK_RECV_NO_ENOBUFS in netlink_set_err()Pablo Neira Ayuso
Currently, ENOBUFS errors are reported to the socket via netlink_set_err() even if NETLINK_RECV_NO_ENOBUFS is set. However, that should not happen. This fixes this problem and it changes the prototype of netlink_set_err() to return the number of sockets that have set the NETLINK_RECV_NO_ENOBUFS socket option. This return value is used in the next patch in these bugfix series. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-28netlink: Adding inode field to /proc/net/netlinkMasatake YAMATO
The Inode field in /proc/net/{tcp,udp,packet,raw,...} is useful to know the types of file descriptors associated to a process. Actually lsof utility uses the field. Unfortunately, unlike /proc/net/{tcp,udp,packet,raw,...}, /proc/net/netlink doesn't have the field. This patch adds the field to /proc/net/netlink. Signed-off-by: Masatake YAMATO <yamato@redhat.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-03netlink: fix for too early rmmodAlexey Dobriyan
Netlink code does module autoload if protocol userspace is asking for is not ready. However, module can dissapear right after it was autoloaded. Example: modprobe/rmmod stress-testing and xfrm_user.ko providing NETLINK_XFRM. netlink_create() in such situation _will_ create userspace socket and _will_not_ pin module. Now if module was removed and we're going to call ->netlink_rcv into nothing: BUG: unable to handle kernel paging request at ffffffffa02f842a ^^^^^^^^^^^^^^^^ modules are loaded near these addresses here IP: [<ffffffffa02f842a>] 0xffffffffa02f842a PGD 161f067 PUD 1623063 PMD baa12067 PTE 0 Oops: 0010 [#1] PREEMPT SMP DEBUG_PAGEALLOC last sysfs file: /sys/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/uevent CPU 1 Pid: 11515, comm: ip Not tainted 2.6.33-rc5-netns-00594-gaaa5728-dirty #6 P5E/P5E RIP: 0010:[<ffffffffa02f842a>] [<ffffffffa02f842a>] 0xffffffffa02f842a RSP: 0018:ffff8800baa3db48 EFLAGS: 00010292 RAX: ffff8800baa3dfd8 RBX: ffff8800be353640 RCX: 0000000000000000 RDX: ffffffff81959380 RSI: ffff8800bab7f130 RDI: 0000000000000001 RBP: ffff8800baa3db58 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000011 R13: ffff8800be353640 R14: ffff8800bcdec240 R15: ffff8800bd488010 FS: 00007f93749656f0(0000) GS:ffff880002300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffffffffa02f842a CR3: 00000000ba82b000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process ip (pid: 11515, threadinfo ffff8800baa3c000, task ffff8800bab7eb30) Stack: ffffffff813637c0 ffff8800bd488000 ffff8800baa3dba8 ffffffff8136397d <0> 0000000000000000 ffffffff81344adc 7fffffffffffffff 0000000000000000 <0> ffff8800baa3ded8 ffff8800be353640 ffff8800bcdec240 0000000000000000 Call Trace: [<ffffffff813637c0>] ? netlink_unicast+0x100/0x2d0 [<ffffffff8136397d>] netlink_unicast+0x2bd/0x2d0 netlink_unicast_kernel: nlk->netlink_rcv(skb); [<ffffffff81344adc>] ? memcpy_fromiovec+0x6c/0x90 [<ffffffff81364263>] netlink_sendmsg+0x1d3/0x2d0 [<ffffffff8133975b>] sock_sendmsg+0xbb/0xf0 [<ffffffff8106cdeb>] ? __lock_acquire+0x27b/0xa60 [<ffffffff810a18c3>] ? might_fault+0x73/0xd0 [<ffffffff810a18c3>] ? might_fault+0x73/0xd0 [<ffffffff8106db22>] ? __lock_release+0x82/0x170 [<ffffffff810a190e>] ? might_fault+0xbe/0xd0 [<ffffffff810a18c3>] ? might_fault+0x73/0xd0 [<ffffffff81344c77>] ? verify_iovec+0x47/0xd0 [<ffffffff8133a509>] sys_sendmsg+0x1a9/0x360 [<ffffffff813c2be5>] ? _raw_spin_unlock_irqrestore+0x65/0x70 [<ffffffff8106aced>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff813c2bc2>] ? _raw_spin_unlock_irqrestore+0x42/0x70 [<ffffffff81197004>] ? __up_read+0x84/0xb0 [<ffffffff8106ac95>] ? trace_hardirqs_on_caller+0x145/0x190 [<ffffffff813c207f>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff8100262b>] system_call_fastpath+0x16/0x1b Code: Bad RIP value. RIP [<ffffffffa02f842a>] 0xffffffffa02f842a RSP <ffff8800baa3db48> CR2: ffffffffa02f842a If module was quickly removed after autoloading, return -E. Return -EPROTONOSUPPORT if module was quickly removed after autoloading. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.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>
2009-11-17netlink: remove subscriptions check on notifierJohannes Berg
The netlink URELEASE notifier doesn't notify for sockets that have been used to receive multicast but it should be called for such sockets as well since they might _also_ be used for sending and not solely for receiving multicast. We will need that for nl80211 (generic netlink sockets) in the future. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-10net: netlink_getname, packet_getname -- use DECLARE_SOCKADDR guardCyrill Gorcunov
Use guard DECLARE_SOCKADDR in a few more places which allow us to catch if the structure copied back is too big. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-05net: pass kern to net_proto_family create functionEric Paris
The generic __sock_create function has a kern argument which allows the security system to make decisions based on if a socket is being created by the kernel or by userspace. This patch passes that flag to the net_proto_family specific create function, so it can do the same thing. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-07net: mark net_proto_ops as constStephen Hemminger
All usages of structure net_proto_ops should be declared const. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-30net: Make setsockopt() optlen be unsigned.David S. Miller
This provides safety against negative optlen at the type level instead of depending upon (sometimes non-trivial) checks against this sprinkled all over the the place, in each and every implementation. Based upon work done by Arjan van de Ven and feedback from Linus Torvalds. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-26net: fix nlmsg len size for skb when error bit is set.John Fastabend
Currently, the nlmsg->len field is not set correctly in netlink_ack() for ack messages that include the nlmsg of the error frame. This corrects the length field passed to __nlmsg_put to use the correct payload size. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-24genetlink: fix netns vs. netlink table locking (2)Johannes Berg
Similar to commit d136f1bd366fdb7e747ca7e0218171e7a00a98a5, there's a bug when unregistering a generic netlink family, which is caught by the might_sleep() added in that commit: BUG: sleeping function called from invalid context at net/netlink/af_netlink.c:183 in_atomic(): 1, irqs_disabled(): 0, pid: 1510, name: rmmod 2 locks held by rmmod/1510: #0: (genl_mutex){+.+.+.}, at: [<ffffffff8138283b>] genl_unregister_family+0x2b/0x130 #1: (rcu_read_lock){.+.+..}, at: [<ffffffff8138270c>] __genl_unregister_mc_group+0x1c/0x120 Pid: 1510, comm: rmmod Not tainted 2.6.31-wl #444 Call Trace: [<ffffffff81044ff9>] __might_sleep+0x119/0x150 [<ffffffff81380501>] netlink_table_grab+0x21/0x100 [<ffffffff813813a3>] netlink_clear_multicast_users+0x23/0x60 [<ffffffff81382761>] __genl_unregister_mc_group+0x71/0x120 [<ffffffff81382866>] genl_unregister_family+0x56/0x130 [<ffffffffa0007d85>] nl80211_exit+0x15/0x20 [cfg80211] [<ffffffffa000005a>] cfg80211_exit+0x1a/0x40 [cfg80211] Fix in the same way by grabbing the netlink table lock before doing rcu_read_lock(). Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-22mm: replace various uses of num_physpages by totalram_pagesJan Beulich
Sizing of memory allocations shouldn't depend on the number of physical pages found in a system, as that generally includes (perhaps a huge amount of) non-RAM pages. The amount of what actually is usable as storage should instead be used as a basis here. Some of the calculations (i.e. those not intending to use high memory) should likely even use (totalram_pages - totalhigh_pages). Signed-off-by: Jan Beulich <jbeulich@novell.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Dave Airlie <airlied@linux.ie> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: "David S. Miller" <davem@davemloft.net> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-14genetlink: fix netns vs. netlink table lockingJohannes Berg
Since my commits introducing netns awareness into genetlink we can get this problem: BUG: scheduling while atomic: modprobe/1178/0x00000002 2 locks held by modprobe/1178: #0: (genl_mutex){+.+.+.}, at: [<ffffffff8135ee1a>] genl_register_mc_grou #1: (rcu_read_lock){.+.+..}, at: [<ffffffff8135eeb5>] genl_register_mc_g Pid: 1178, comm: modprobe Not tainted 2.6.31-rc8-wl-34789-g95cb731-dirty # Call Trace: [<ffffffff8103e285>] __schedule_bug+0x85/0x90 [<ffffffff81403138>] schedule+0x108/0x588 [<ffffffff8135b131>] netlink_table_grab+0xa1/0xf0 [<ffffffff8135c3a7>] netlink_change_ngroups+0x47/0x100 [<ffffffff8135ef0f>] genl_register_mc_group+0x12f/0x290 because I overlooked that netlink_table_grab() will schedule, thinking it was just the rwlock. However, in the contention case, that isn't actually true. Fix this by letting the code grab the netlink table lock first and then the RCU for netns protection. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-25netlink: constify nlmsghdr argumentsPatrick McHardy
Consitfy nlmsghdr arguments to a couple of functions as preparation for the next patch, which will constify the netlink message data in all nfnetlink users. Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-07-15net/compat/wext: send different messages to compat tasksJohannes Berg
Wireless extensions have the unfortunate problem that events are multicast netlink messages, and are not independent of pointer size. Thus, currently 32-bit tasks on 64-bit platforms cannot properly receive events and fail with all kinds of strange problems, for instance wpa_supplicant never notices disassociations, due to the way the 64-bit event looks (to a 32-bit process), the fact that the address is all zeroes is lost, it thinks instead it is 00:00:00:00:01:00. The same problem existed with the ioctls, until David Miller fixed those some time ago in an heroic effort. A different problem caused by this is that we cannot send the ASSOCREQIE/ASSOCRESPIE events because sending them causes a 32-bit wpa_supplicant on a 64-bit system to overwrite its internal information, which is worse than it not getting the information at all -- so we currently resort to sending a custom string event that it then parses. This, however, has a severe size limitation we are frequently hitting with modern access points; this limitation would can be lifted after this patch by sending the correct binary, not custom, event. A similar problem apparently happens for some other netlink users on x86_64 with 32-bit tasks due to the alignment for 64-bit quantities. In order to fix these problems, I have implemented a way to send compat messages to tasks. When sending an event, we send the non-compat event data together with a compat event data in skb_shinfo(main_skb)->frag_list. Then, when the event is read from the socket, the netlink code makes sure to pass out only the skb that is compatible with the task. This approach was suggested by David Miller, my original approach required always sending two skbs but that had various small problems. To determine whether compat is needed or not, I have used the MSG_CMSG_COMPAT flag, and adjusted the call path for recv and recvfrom to include it, even if those calls do not have a cmsg parameter. I have not solved one small part of the problem, and I don't think it is necessary to: if a 32-bit application uses read() rather than any form of recvmsg() it will still get the wrong (64-bit) event. However, neither do applications actually do this, nor would it be a regression. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-12netlink: use call_rcu for netlink_change_ngroupsJohannes Berg
For the network namespace work in generic netlink I need to be able to call this function under rcu_read_lock(), otherwise the locking becomes a nightmare and more locks would be needed. Instead, just embed a struct rcu_head (actually a struct listeners_rcu_head that also carries the pointer to the memory block) into the listeners memory so we can use call_rcu() instead of synchronising and then freeing. No rcu_barrier() is needed since this code cannot be modular. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-12netlink: remove unused exportsJohannes Berg
I added those myself in commits b4ff4f04 and 84659eb5, but I see no reason now why they should be exported, only generic netlink uses them which cannot be modular. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-18net: correct off-by-one write allocations reportsEric Dumazet
commit 2b85a34e911bf483c27cfdd124aeb1605145dc80 (net: No more expensive sock_hold()/sock_put() on each tx) changed initial sk_wmem_alloc value. We need to take into account this offset when reporting sk_wmem_alloc to user, in PROC_FS files or various ioctls (SIOCOUTQ/TIOCOUTQ) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-24netlink: add NETLINK_NO_ENOBUFS socket flagPablo Neira Ayuso
This patch adds the NETLINK_NO_ENOBUFS socket flag. This flag can be used by unicast and broadcast listeners to avoid receiving ENOBUFS errors. Generally speaking, ENOBUFS errors are useful to notify two things to the listener: a) You may increase the receiver buffer size via setsockopt(). b) You have lost messages, you may be out of sync. In some cases, ignoring ENOBUFS errors can be useful. For example: a) nfnetlink_queue: this subsystem does not have any sort of resync method and you can decide to ignore ENOBUFS once you have set a given buffer size. b) ctnetlink: you can use this together with the socket flag NETLINK_BROADCAST_SEND_ERROR to stop getting ENOBUFS errors as you do not need to resync (packets whose event are not delivered are drop to provide reliable logging and state-synchronization). Moreover, the use of NETLINK_NO_ENOBUFS also reduces a "go up, go down" effect in terms of performance which is due to the netlink congestion control when the listener cannot back off. The effect is the following: 1) throughput rate goes up and netlink messages are inserted in the receiver buffer. 2) Then, netlink buffer fills and overruns (set on nlk->state bit 0). 3) While the listener empties the receiver buffer, netlink keeps dropping messages. Thus, throughput goes dramatically down. 4) Then, once the listener has emptied the buffer (nlk->state bit 0 is set off), goto step 1. This effect is easy to trigger with netlink broadcast under heavy load, and it is more noticeable when using a big receiver buffer. You can find some results in [1] that show this problem. [1] http://1984.lsi.us.es/linux/netlink/ This patch also includes the use of sk_drop to account the number of netlink messages drop due to overrun. This value is shown in /proc/net/netlink. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-24Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
2009-03-23nefilter: nfnetlink: add nfnetlink_set_err and use it in ctnetlinkPablo Neira Ayuso
This patch adds nfnetlink_set_err() to propagate the error to netlink broadcast listener in case of memory allocation errors in the message building. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-05Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/tokenring/tmspci.c drivers/net/ucc_geth_mii.c
2009-03-03netlink: invert error code in netlink_set_err()Pablo Neira Ayuso
The callers of netlink_set_err() currently pass a negative value as parameter for the error code. However, sk->sk_err wants a positive error value. Without this patch, skb_recv_datagram() called by netlink_recvmsg() may return a positive value to report an error. Another choice to fix this is to change callers to pass a positive error value, but this seems a bit inconsistent and error prone to me. Indeed, the callers of netlink_set_err() assumed that the (usual) negative value for error codes was fine before this patch :). This patch also includes some documentation in docbook format for netlink_set_err() to avoid this sort of confusion. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-26netlink: remove some pointless conditionals before kfree_skb()Wei Yongjun
Remove some pointless conditionals before kfree_skb(). Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-24netlink: change nlmsg_notify() return value logicPablo Neira Ayuso
This patch changes the return value of nlmsg_notify() as follows: If NETLINK_BROADCAST_ERROR is set by any of the listeners and an error in the delivery happened, return the broadcast error; else if there are no listeners apart from the socket that requested a change with the echo flag, return the result of the unicast notification. Thus, with this patch, the unicast notification is handled in the same way of a broadcast listener that has set the NETLINK_BROADCAST_ERROR socket flag. This patch is useful in case that the caller of nlmsg_notify() wants to know the result of the delivery of a netlink notification (including the broadcast delivery) and take any action in case that the delivery failed. For example, ctnetlink can drop packets if the event delivery failed to provide reliable logging and state-synchronization at the cost of dropping packets. This patch also modifies the rtnetlink code to ignore the return value of rtnl_notify() in all callers. The function rtnl_notify() (before this patch) returned the error of the unicast notification which makes rtnl_set_sk_err() reports errors to all listeners. This is not of any help since the origin of the change (the socket that requested the echoing) notices the ENOBUFS error if the notification fails and should resync itself. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-20netlink: add NETLINK_BROADCAST_ERROR socket optionPablo Neira Ayuso
This patch adds NETLINK_BROADCAST_ERROR which is a netlink socket option that the listener can set to make netlink_broadcast() return errors in the delivery to the caller. This option is useful if the caller of netlink_broadcast() do something with the result of the message delivery, like in ctnetlink where it drops a network packet if the event delivery failed, this is used to enable reliable logging and state-synchronization. If this socket option is not set, netlink_broadcast() only reports ESRCH errors and silently ignore ENOBUFS errors, which is what most netlink_broadcast() callers should do. This socket option is based on a suggestion from Patrick McHardy. Patrick McHardy can exchange this patch for a beer from me ;). Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-05netlink: change return-value logic of netlink_broadcast()Pablo Neira Ayuso
Currently, netlink_broadcast() reports errors to the caller if no messages at all were delivered: 1) If, at least, one message has been delivered correctly, returns 0. 2) Otherwise, if no messages at all were delivered due to skb_clone() failure, return -ENOBUFS. 3) Otherwise, if there are no listeners, return -ESRCH. With this patch, the caller knows if the delivery of any of the messages to the listeners have failed: 1) If it fails to deliver any message (for whatever reason), return -ENOBUFS. 2) Otherwise, if all messages were delivered OK, returns 0. 3) Otherwise, if no listeners, return -ESRCH. In the current ctnetlink code and in Netfilter in general, we can add reliable logging and connection tracking event delivery by dropping the packets whose events were not successfully delivered over Netlink. Of course, this option would be settable via /proc as this approach reduces performance (in terms of filtered connections per seconds by a stateful firewall) but providing reliable logging and event delivery (for conntrackd) in return. This patch also changes some clients of netlink_broadcast() that may report ENOBUFS errors via printk. This error handling is not of any help. Instead, the userspace daemons that are listening to those netlink messages should resync themselves with the kernel-side if they hit ENOBUFS. BTW, netlink_broadcast() clients include those that call cn_netlink_send(), nlmsg_multicast() and genlmsg_multicast() since they internally call netlink_broadcast() and return its error value. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-24net: Make sure BHs are disabled in sock_prot_inuse_add()Eric Dumazet
There is still a call to sock_prot_inuse_add() in af_netlink while in a preemptable section. Add explicit BH disable around this call. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23net: Make sure BHs are disabled in sock_prot_inuse_add()David S. Miller
The rule of calling sock_prot_inuse_add() is that BHs must be disabled. Some new calls were added where this was not true and this tiggers warnings as reported by Ilpo. Fix this by adding explicit BH disabling around those call sites. Signed-off-by: David S. Miller <davem@davemloft.net>