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* net: unix: inherit SOCK_PASS{CRED, SEC} flags from socket to fix raceDaniel Borkmann2013-10-201-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the case of credentials passing in unix stream sockets (dgram sockets seem not affected), we get a rather sparse race after commit 16e5726 ("af_unix: dont send SCM_CREDENTIALS by default"). We have a stream server on receiver side that requests credential passing from senders (e.g. nc -U). Since we need to set SO_PASSCRED on each spawned/accepted socket on server side to 1 first (as it's not inherited), it can happen that in the time between accept() and setsockopt() we get interrupted, the sender is being scheduled and continues with passing data to our receiver. At that time SO_PASSCRED is neither set on sender nor receiver side, hence in cmsg's SCM_CREDENTIALS we get eventually pid:0, uid:65534, gid:65534 (== overflow{u,g}id) instead of what we actually would like to see. On the sender side, here nc -U, the tests in maybe_add_creds() invoked through unix_stream_sendmsg() would fail, as at that exact time, as mentioned, the sender has neither SO_PASSCRED on his side nor sees it on the server side, and we have a valid 'other' socket in place. Thus, sender believes it would just look like a normal connection, not needing/requesting SO_PASSCRED at that time. As reverting 16e5726 would not be an option due to the significant performance regression reported when having creds always passed, one way/trade-off to prevent that would be to set SO_PASSCRED on the listener socket and allow inheriting these flags to the spawned socket on server side in accept(). It seems also logical to do so if we'd tell the listener socket to pass those flags onwards, and would fix the race. Before, strace: recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"blub\n", 4096}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=0, uid=65534, gid=65534}}, msg_flags=0}, 0) = 5 After, strace: recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"blub\n", 4096}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=11580, uid=1000, gid=1000}}, msg_flags=0}, 0) = 5 Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* unix_diag: fix info leakMathias Krause2013-10-021-0/+1
| | | | | | | | | When filling the netlink message we miss to wipe the pad field, therefore leak one byte of heap memory to userland. Fix this by setting pad to 0. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: fix bug on large send()Eric Dumazet2013-08-121-1/+2
| | | | | | | | | | | | | | commit e370a723632 ("af_unix: improve STREAM behavior with fragmented memory") added a bug on large send() because the skb_copy_datagram_from_iovec() call always start from the beginning of iovec. We must instead use the @sent variable to properly skip the already processed part. Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: attempt high order allocations in sock_alloc_send_pskb()Eric Dumazet2013-08-101-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding paged frags skbs to af_unix sockets introduced a performance regression on large sends because of additional page allocations, even if each skb could carry at least 100% more payload than before. We can instruct sock_alloc_send_pskb() to attempt high order allocations. Most of the time, it does a single page allocation instead of 8. I added an additional parameter to sock_alloc_send_pskb() to let other users to opt-in for this new feature on followup patches. Tested: Before patch : $ netperf -t STREAM_STREAM STREAM STREAM TEST Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 2304 212992 212992 10.00 46861.15 After patch : $ netperf -t STREAM_STREAM STREAM STREAM TEST Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 2304 212992 212992 10.00 57981.11 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: improve STREAM behavior with fragmented memoryEric Dumazet2013-08-101-35/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | unix_stream_sendmsg() currently uses order-2 allocations, and we had numerous reports this can fail. The __GFP_REPEAT flag present in sock_alloc_send_pskb() is not helping. This patch extends the work done in commit eb6a24816b247c ("af_unix: reduce high order page allocations) for datagram sockets. This opens the possibility of zero copy IO (splice() and friends) The trick is to not use skb_pull() anymore in recvmsg() path, and instead add a @consumed field in UNIXCB() to track amount of already read payload in the skb. There is a performance regression for large sends because of extra page allocations that will be addressed in a follow-up patch, allowing sock_alloc_send_pskb() to attempt high order page allocations. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2013-07-101-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: "This is a re-do of the net-next pull request for the current merge window. The only difference from the one I made the other day is that this has Eliezer's interface renames and the timeout handling changes made based upon your feedback, as well as a few bug fixes that have trickeled in. Highlights: 1) Low latency device polling, eliminating the cost of interrupt handling and context switches. Allows direct polling of a network device from socket operations, such as recvmsg() and poll(). Currently ixgbe, mlx4, and bnx2x support this feature. Full high level description, performance numbers, and design in commit 0a4db187a999 ("Merge branch 'll_poll'") From Eliezer Tamir. 2) With the routing cache removed, ip_check_mc_rcu() gets exercised more than ever before in the case where we have lots of multicast addresses. Use a hash table instead of a simple linked list, from Eric Dumazet. 3) Add driver for Atheros CQA98xx 802.11ac wireless devices, from Bartosz Markowski, Janusz Dziedzic, Kalle Valo, Marek Kwaczynski, Marek Puzyniak, Michal Kazior, and Sujith Manoharan. 4) Support reporting the TUN device persist flag to userspace, from Pavel Emelyanov. 5) Allow controlling network device VF link state using netlink, from Rony Efraim. 6) Support GRE tunneling in openvswitch, from Pravin B Shelar. 7) Adjust SOCK_MIN_RCVBUF and SOCK_MIN_SNDBUF for modern times, from Daniel Borkmann and Eric Dumazet. 8) Allow controlling of TCP quickack behavior on a per-route basis, from Cong Wang. 9) Several bug fixes and improvements to vxlan from Stephen Hemminger, Pravin B Shelar, and Mike Rapoport. In particular, support receiving on multiple UDP ports. 10) Major cleanups, particular in the area of debugging and cookie lifetime handline, to the SCTP protocol code. From Daniel Borkmann. 11) Allow packets to cross network namespaces when traversing tunnel devices. From Nicolas Dichtel. 12) Allow monitoring netlink traffic via AF_PACKET sockets, in a manner akin to how we monitor real network traffic via ptype_all. From Daniel Borkmann. 13) Several bug fixes and improvements for the new alx device driver, from Johannes Berg. 14) Fix scalability issues in the netem packet scheduler's time queue, by using an rbtree. From Eric Dumazet. 15) Several bug fixes in TCP loss recovery handling, from Yuchung Cheng. 16) Add support for GSO segmentation of MPLS packets, from Simon Horman. 17) Make network notifiers have a real data type for the opaque pointer that's passed into them. Use this to properly handle network device flag changes in arp_netdev_event(). From Jiri Pirko and Timo Teräs. 18) Convert several drivers over to module_pci_driver(), from Peter Huewe. 19) tcp_fixup_rcvbuf() can loop 500 times over loopback, just use a O(1) calculation instead. From Eric Dumazet. 20) Support setting of explicit tunnel peer addresses in ipv6, just like ipv4. From Nicolas Dichtel. 21) Protect x86 BPF JIT against spraying attacks, from Eric Dumazet. 22) Prevent a single high rate flow from overruning an individual cpu during RX packet processing via selective flow shedding. From Willem de Bruijn. 23) Don't use spinlocks in TCP md5 signing fast paths, from Eric Dumazet. 24) Don't just drop GSO packets which are above the TBF scheduler's burst limit, chop them up so they are in-bounds instead. Also from Eric Dumazet. 25) VLAN offloads are missed when configured on top of a bridge, fix from Vlad Yasevich. 26) Support IPV6 in ping sockets. From Lorenzo Colitti. 27) Receive flow steering targets should be updated at poll() time too, from David Majnemer. 28) Fix several corner case regressions in PMTU/redirect handling due to the routing cache removal, from Timo Teräs. 29) We have to be mindful of ipv4 mapped ipv6 sockets in upd_v6_push_pending_frames(). From Hannes Frederic Sowa. 30) Fix L2TP sequence number handling bugs, from James Chapman." * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1214 commits) drivers/net: caif: fix wrong rtnl_is_locked() usage drivers/net: enic: release rtnl_lock on error-path vhost-net: fix use-after-free in vhost_net_flush net: mv643xx_eth: do not use port number as platform device id net: sctp: confirm route during forward progress virtio_net: fix race in RX VQ processing virtio: support unlocked queue poll net/cadence/macb: fix bug/typo in extracting gem_irq_read_clear bit Documentation: Fix references to defunct linux-net@vger.kernel.org net/fs: change busy poll time accounting net: rename low latency sockets functions to busy poll bridge: fix some kernel warning in multicast timer sfc: Fix memory leak when discarding scattered packets sit: fix tunnel update via netlink dt:net:stmmac: Add dt specific phy reset callback support. dt:net:stmmac: Add support to dwmac version 3.610 and 3.710 dt:net:stmmac: Allocate platform data only if its NULL. net:stmmac: fix memleak in the open method ipv6: rt6_check_neigh should successfully verify neigh if no NUD information are available net: ipv6: fix wrong ping_v6_sendmsg return value ...
| * net: Convert uses of typedef ctl_table to struct ctl_tableJoe Perches2013-06-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reduce the uses of this unnecessary typedef. Done via perl script: $ git grep --name-only -w ctl_table net | \ xargs perl -p -i -e '\ sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \ s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge' Reflow the modified lines that now exceed 80 columns. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | af_unix: use freezable blocking calls in readColin Cross2013-05-121-1/+2
|/ | | | | | | | | | | | | | | | | Avoid waking up every thread sleeping in read call on an AF_UNIX socket during suspend and resume by calling a freezable blocking call. Previous patches modified the freezer to avoid sending wakeups to threads that are blocked in freezable blocking calls. This call was selected to be converted to a freezable call because it doesn't hold any locks or release any resources when interrupted that might be needed by another freezing task or a kernel driver during suspend, and is a common site where idle userspace tasks are blocked. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* af_unix: fix a fatal race with bit fieldsEric Dumazet2013-05-011-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using bit fields is dangerous on ppc64/sparc64, as the compiler [1] uses 64bit instructions to manipulate them. If the 64bit word includes any atomic_t or spinlock_t, we can lose critical concurrent changes. This is happening in af_unix, where unix_sk(sk)->gc_candidate/ gc_maybe_cycle/lock share the same 64bit word. This leads to fatal deadlock, as one/several cpus spin forever on a spinlock that will never be available again. A safer way would be to use a long to store flags. This way we are sure compiler/arch wont do bad things. As we own unix_gc_lock spinlock when clearing or setting bits, we can use the non atomic __set_bit()/__clear_bit(). recursion_level can share the same 64bit location with the spinlock, as it is set only with this spinlock held. [1] bug fixed in gcc-4.8.0 : http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52080 Reported-by: Ambrose Feinstein <ambrose@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2013-04-301-13/+12
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c drivers/net/ethernet/emulex/benet/be.h include/net/tcp.h net/mac802154/mac802154.h Most conflicts were minor overlapping stuff. The be2net driver brought in some fixes that added __vlan_put_tag calls, which in net-next take an additional argument. Signed-off-by: David S. Miller <davem@davemloft.net>
| * unix/stream: fix peeking with an offset larger than data in queueBenjamin Poirier2013-04-301-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | Currently, peeking on a unix stream socket with an offset larger than len of the data in the sk receive queue returns immediately with bogus data. This patch fixes this so that the behavior is the same as peeking with no offset on an empty queue: the caller blocks. Signed-off-by: Benjamin Poirier <bpoirier@suse.de> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2013-04-231-1/+1
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/ethernet/emulex/benet/be_main.c drivers/net/ethernet/intel/igb/igb_main.c drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c include/net/scm.h net/batman-adv/routing.c net/ipv4/tcp_input.c The e{uid,gid} --> {uid,gid} credentials fix conflicted with the cleanup in net-next to now pass cred structs around. The be2net driver had a bug fix in 'net' that overlapped with the VLAN interface changes by Patrick McHardy in net-next. An IGB conflict existed because in 'net' the build_skb() support was reverted, and in 'net-next' there was a comment style fix within that code. Several batman-adv conflicts were resolved by making sure that all calls to batadv_is_my_mac() are changed to have a new bat_priv first argument. Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO rewrite in 'net-next', mostly overlapping changes. Thanks to Stephen Rothwell and Antonio Quartulli for help with several of these merge resolutions. Signed-off-by: David S. Miller <davem@davemloft.net>
* | scm: Stop passing struct credEric W. Biederman2013-04-081-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | Now that uids and gids are completely encapsulated in kuid_t and kgid_t we no longer need to pass struct cred which allowed us to test both the uid and the user namespace for equality. Passing struct cred potentially allows us to pass the entire group list as BSD does but I don't believe the cost of cache line misses justifies retaining code for a future potential application. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2013-04-081-3/+3
|\| | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/nfc/microread/mei.c net/netfilter/nfnetlink_queue_core.c Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which some cleanups are going to go on-top. Signed-off-by: David S. Miller <davem@davemloft.net>
| * af_unix: If we don't care about credentials coallesce all messagesEric W. Biederman2013-04-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was reported that the following LSB test case failed https://lsbbugs.linuxfoundation.org/attachment.cgi?id=2144 because we were not coallescing unix stream messages when the application was expecting us to. The problem was that the first send was before the socket was accepted and thus sock->sk_socket was NULL in maybe_add_creds, and the second send after the socket was accepted had a non-NULL value for sk->socket and thus we could tell the credentials were not needed so we did not bother. The unnecessary credentials on the first message cause unix_stream_recvmsg to start verifying that all messages had the same credentials before coallescing and then the coallescing failed because the second message had no credentials. Ignoring credentials when we don't care in unix_stream_recvmsg fixes a long standing pessimization which would fail to coallesce messages when reading from a unix stream socket if the senders were different even if we did not care about their credentials. I have tested this and verified that the in the LSB test case mentioned above that the messages do coallesce now, while the were failing to coallesce without this change. Reported-by: Karel Srot <ksrot@redhat.com> Reported-by: Ding Tianhong <dingtianhong@huawei.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * Revert "af_unix: dont send SCM_CREDENTIAL when dest socket is NULL"Eric W. Biederman2013-04-051-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 14134f6584212d585b310ce95428014b653dfaf6. The problem that the above patch was meant to address is that af_unix messages are not being coallesced because we are sending unnecesarry credentials. Not sending credentials in maybe_add_creds totally breaks unconnected unix domain sockets that wish to send credentails to other sockets. In practice this break some versions of udev because they receive a message and the sending uid is bogus so they drop the message. Reported-by: Sven Joachim <svenjoac@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: fix smatch warnings inside datagram_pollJacob Keller2013-04-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Commit 7d4c04fc170087119727119074e72445f2bb192b ("net: add option to enable error queue packets waking select") has an issue due to operator precedence causing the bit-wise OR to bind to the sock_flags call instead of the result of the terniary conditional. This fixes the *_poll functions to work properly. The old code results in "mask |= POLLPRI" instead of what was intended, which is to only include POLLPRI when the socket option is enabled. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: add option to enable error queue packets waking selectKeller, Jacob E2013-04-011-1/+3
|/ | | | | | | | | | | | | | | | | | | | | Currently, when a socket receives something on the error queue it only wakes up the socket on select if it is in the "read" list, that is the socket has something to read. It is useful also to wake the socket if it is in the error list, which would enable software to wait on error queue packets without waking up for regular data on the socket. The main use case is for receiving timestamped transmit packets which return the timestamp to the socket via the error queue. This enables an application to select on the socket for the error queue only instead of for the regular traffic. -v2- * Added the SO_SELECT_ERR_QUEUE socket option to every architechture specific file * Modified every socket poll function that checks error queue Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Cc: Jeffrey Kirsher <jeffrey.t.kirsher@intel.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Matthew Vick <matthew.vick@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: dont send SCM_CREDENTIAL when dest socket is NULLdingtianhong2013-03-261-2/+2
| | | | | | | | | | | SCM_SCREDENTIALS should apply to write() syscalls only either source or destination socket asserted SOCK_PASSCRED. The original implememtation in maybe_add_creds is wrong, and breaks several LSB testcases ( i.e. /tset/LSB.os/netowkr/recvfrom/T.recvfrom). Origionally-authored-by: Karel Srot <ksrot@redhat.com> Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* unix: fix a race condition in unix_release()Paul Moore2013-03-251-4/+3
| | | | | | | | | | | | | | | | | | | | | | As reported by Jan, and others over the past few years, there is a race condition caused by unix_release setting the sock->sk pointer to NULL before properly marking the socket as dead/orphaned. This can cause a problem with the LSM hook security_unix_may_send() if there is another socket attempting to write to this partially released socket in between when sock->sk is set to NULL and it is marked as dead/orphaned. This patch fixes this by only setting sock->sk to NULL after the socket has been marked as dead; I also take the opportunity to make unix_release_sock() a void function as it only ever returned 0/success. Dave, I think this one should go on the -stable pile. Special thanks to Jan for coming up with a reproducer for this problem. Reported-by: Jan Stancek <jan.stancek@gmail.com> Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* hlist: drop the node parameter from iteratorsSasha Levin2013-02-282-9/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-02-271-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
| * new helper: file_inode(file)Al Viro2013-02-231-1/+1
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | net: proc: change proc_net_remove to remove_proc_entryGao feng2013-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | proc_net_remove is only used to remove proc entries that under /proc/net,it's not a general function for removing proc entries of netns. if we want to remove some proc entries which under /proc/net/stat/, we still need to call remove_proc_entry. this patch use remove_proc_entry to replace proc_net_remove. we can remove proc_net_remove after this patch. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: proc: change proc_net_fops_create to proc_createGao feng2013-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Right now, some modules such as bonding use proc_create to create proc entries under /proc/net/, and other modules such as ipv4 use proc_net_fops_create. It looks a little chaos.this patch changes all of proc_net_fops_create to proc_create. we can remove proc_net_fops_create after this patch. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | unix: Use FIELD_SIZEOF() in af_unix_init().YOSHIFUJI Hideaki / 吉藤英明2013-01-101-2/+1
|/ | | | | Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Don't export sysctls to unprivileged usersEric W. Biederman2012-11-191-0/+4
| | | | | | | | | | | | | In preparation for supporting the creation of network namespaces by unprivileged users, modify all of the per net sysctl exports and refuse to allow them to unprivileged users. This makes it safe for unprivileged users in general to access per net sysctls, and allows sysctls to be exported to unprivileged users on an individual basis as they are deemed safe. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock-diag: Report shutdown for inet and unix sockets (v2)Pavel Emelyanov2012-10-231-0/+3
| | | | | | | Make it simple -- just put new nlattr with just sk->sk_shutdown bits. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: old_cred is surplusAlan Cox2012-09-171-4/+1
| | | | | Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: Rename pid to portid to avoid confusionEric W. Biederman2012-09-101-7/+7
| | | | | | | | | | | | | | | 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>
* af_unix: fix shutdown parameter checkingXi Wang2012-08-311-4/+8
| | | | | | | Return -EINVAL rather than 0 given an invalid "mode" parameter. Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_netlink: force credentials passing [CVE-2012-3520]Eric Dumazet2012-08-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pablo Neira Ayuso discovered that avahi and potentially NetworkManager accept spoofed Netlink messages because of a kernel bug. The kernel passes all-zero SCM_CREDENTIALS ancillary data to the receiver if the sender did not provide such data, instead of not including any such data at all or including the correct data from the peer (as it is the case with AF_UNIX). This bug was introduced in commit 16e572626961 (af_unix: dont send SCM_CREDENTIALS by default) This patch forces passing credentials for netlink, as before the regression. Another fix would be to not add SCM_CREDENTIALS in netlink messages if not provided by the sender, but it might break some programs. With help from Florian Weimer & Petr Matousek This issue is designated as CVE-2012-3520 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-08-011-50/+43
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ...
| * clean unix_bind() up a bitAl Viro2012-07-291-45/+43
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * pull mnt_want_write()/mnt_drop_write() into ↵Al Viro2012-07-291-4/+0
| | | | | | | | | | | | | | | | | | kern_path_create()/done_path_create() resp. One side effect - attempt to create a cross-device link on a read-only fs fails with EROFS instead of EXDEV now. Makes more sense, POSIX allows, etc. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * new helper: done_path_create()Al Viro2012-07-291-5/+4
| | | | | | | | | | | | releases what needs to be released after {kern,user}_path_create() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | net: make sock diag per-namespaceAndrey Vagin2012-07-171-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch sock_diag works for init_net only and dumps information about sockets from all namespaces. This patch expands sock_diag for all name-spaces. It creates a netlink kernel socket for each netns and filters data during dumping. v2: filter accoding with netns in all places remove an unused variable. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Pavel Emelyanov <xemul@parallels.com> CC: Eric Dumazet <eric.dumazet@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Andrew Vagin <avagin@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | unix_diag: Do not use RTA_PUT() macrosThomas Graf2012-06-281-47/+33
| | | | | | | | | | | | | | | | Also, no need to trim on nlmsg_put() failure, nothing has been added yet. We also want to use nlmsg_end(), nlmsg_new() and nlmsg_free(). Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* | unix_diag: Move away from NLMSG_PUT().David S. Miller2012-06-271-11/+13
| | | | | | | | | | | | | | And use nlmsg_data() while we're here too and remove useless casts. Signed-off-by: David S. Miller <davem@davemloft.net>
* | af_unix: remove unix_iter_stateEric Dumazet2012-06-101-5/+1
| | | | | | | | | | | | | | | | | | | | | | As pointed out by Michael Tokarev , struct unix_iter_state is no longer needed. Suggested-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | af_unix: speedup /proc/net/unixEric Dumazet2012-06-082-48/+68
|/ | | | | | | | | | | | | | | | | | | | | | | | | /proc/net/unix has quadratic behavior, and can hold unix_table_lock for a while if high number of unix sockets are alive. (90 ms for 200k sockets...) We already have a hash table, so its quite easy to use it. Problem is unbound sockets are still hashed in a single hash slot (unix_socket_table[UNIX_HASH_TABLE]) This patch also spreads unbound sockets to 256 hash slots, to speedup both /proc/net/unix and unix_diag. Time to read /proc/net/unix with 200k unix sockets : (time dd if=/proc/net/unix of=/dev/null bs=4k) before : 520 secs after : 2 secs Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sock_diag_handler structs can be constShan Wei2012-04-261-1/+1
| | | | | | | | read only, so change it to const. Signed-off-by: Shan Wei <davidshan@tencent.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Convert all sysctl registrations to register_net_sysctlEric W. Biederman2012-04-211-7/+1
| | | | | | | | | | | | This results in code with less boiler plate that is a bit easier to read. Additionally stops us from using compatibility code in the sysctl core, hastening the day when the compatibility code can be removed. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Move all of the network sysctls without a namespace into init_net.Eric W. Biederman2012-04-211-1/+1
| | | | | | | | | | | | | | | | This makes it clearer which sysctls are relative to your current network namespace. This makes it a little less error prone by not exposing sysctls for the initial network namespace in other namespaces. This is the same way we handle all of our other network interfaces to userspace and I can't honestly remember why we didn't do this for sysctls right from the start. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: cleanup unsigned to unsigned intEric Dumazet2012-04-151-10/+11
| | | | | | | Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: reduce high order page allocationsEric Dumazet2012-04-031-3/+12
| | | | | | | | | | | | | | | | | | | | | | | | | unix_dgram_sendmsg() currently builds linear skbs, and this can stress page allocator with high order page allocations. When memory gets fragmented, this can eventually fail. We can try to use order-2 allocations for skb head (SKB_MAX_ALLOC) plus up to 16 page fragments to lower pressure on buddy allocator. This patch has no effect on messages of less than 16064 bytes. (on 64bit arches with PAGE_SIZE=4096) For bigger messages (from 16065 to 81600 bytes), this patch brings reliability at the expense of performance penalty because of extra pages allocations. netperf -t DG_STREAM -T 0,2 -- -m 16064 -s 200000 ->4086040 Messages / 10s netperf -t DG_STREAM -T 0,2 -- -m 16068 -s 200000 ->3901747 Messages / 10s Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* poll: add poll_requested_events() and poll_does_not_wait() functionsHans Verkuil2012-03-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some cases the poll() implementation in a driver has to do different things depending on the events the caller wants to poll for. An example is when a driver needs to start a DMA engine if the caller polls for POLLIN, but doesn't want to do that if POLLIN is not requested but instead only POLLOUT or POLLPRI is requested. This is something that can happen in the video4linux subsystem among others. Unfortunately, the current epoll/poll/select implementation doesn't provide that information reliably. The poll_table_struct does have it: it has a key field with the event mask. But once a poll() call matches one or more bits of that mask any following poll() calls are passed a NULL poll_table pointer. Also, the eventpoll implementation always left the key field at ~0 instead of using the requested events mask. This was changed in eventpoll.c so the key field now contains the actual events that should be polled for as set by the caller. The solution to the NULL poll_table pointer is to set the qproc field to NULL in poll_table once poll() matches the events, not the poll_table pointer itself. That way drivers can obtain the mask through a new poll_requested_events inline. The poll_table_struct can still be NULL since some kernel code calls it internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h). In that case poll_requested_events() returns ~0 (i.e. all events). Very rarely drivers might want to know whether poll_wait will actually wait. If another earlier file descriptor in the set already matched the events the caller wanted to wait for, then the kernel will return from the select() call without waiting. This might be useful information in order to avoid doing expensive work. A new helper function poll_does_not_wait() is added that drivers can use to detect this situation. This is now used in sock_poll_wait() in include/net/sock.h. This was the only place in the kernel that needed this information. Drivers should no longer access any of the poll_table internals, but use the poll_requested_events() and poll_does_not_wait() access functions instead. In order to enforce that the poll_table fields are now prepended with an underscore and a comment was added warning against using them directly. This required a change in unix_dgram_poll() in unix/af_unix.c which used the key field to get the requested events. It's been replaced by a call to poll_requested_events(). For qproc it was especially important to change its name since the behavior of that field changes with this patch since this function pointer can now be NULL when that wasn't possible in the past. Any driver accessing the qproc or key fields directly will now fail to compile. Some notes regarding the correctness of this patch: the driver's poll() function is called with a 'struct poll_table_struct *wait' argument. This pointer may or may not be NULL, drivers can never rely on it being one or the other as that depends on whether or not an earlier file descriptor in the select()'s fdset matched the requested events. There are only three things a driver can do with the wait argument: 1) obtain the key field: events = wait ? wait->key : ~0; This will still work although it should be replaced with the new poll_requested_events() function (which does exactly the same). This will now even work better, since wait is no longer set to NULL unnecessarily. 2) use the qproc callback. This could be deadly since qproc can now be NULL. Renaming qproc should prevent this from happening. There are no kernel drivers that actually access this callback directly, BTW. 3) test whether wait == NULL to determine whether poll would return without waiting. This is no longer sufficient as the correct test is now wait == NULL || wait->_qproc == NULL. However, the worst that can happen here is a slight performance hit in the case where wait != NULL and wait->_qproc == NULL. In that case the driver will assume that poll_wait() will actually add the fd to the set of waiting file descriptors. Of course, poll_wait() will not do that since it tests for wait->_qproc. This will not break anything, though. There is only one place in the whole kernel where this happens (sock_poll_wait() in include/net/sock.h) and that code will be replaced by a call to poll_does_not_wait() in the next patch. Note that even if wait->_qproc != NULL drivers cannot rely on poll_wait() actually waiting. The next file descriptor from the set might match the event mask and thus any possible waits will never happen. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-03-212-22/+17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "This is _not_ all; in particular, Miklos' and Jan's stuff is not there yet." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits) ext4: initialization of ext4_li_mtx needs to be done earlier debugfs-related mode_t whack-a-mole hfsplus: add an ioctl to bless files hfsplus: change finder_info to u32 hfsplus: initialise userflags qnx4: new helper - try_extent() qnx4: get rid of qnx4_bread/qnx4_getblk take removal of PF_FORKNOEXEC to flush_old_exec() trim includes in inode.c um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it um: embed ->stub_pages[] into mmu_context gadgetfs: list_for_each_safe() misuse ocfs2: fix leaks on failure exits in module_init ecryptfs: make register_filesystem() the last potential failure exit ntfs: forgets to unregister sysctls on register_filesystem() failure logfs: missing cleanup on register_filesystem() failure jfs: mising cleanup on register_filesystem() failure make configfs_pin_fs() return root dentry on success configfs: configfs_create_dir() has parent dentry in dentry->d_parent configfs: sanitize configfs_create() ...
| * switch touch_atime to struct pathAl Viro2012-03-211-2/+2
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * switch unix_sock to struct pathAl Viro2012-03-212-21/+16
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>