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2008-06-27af_unix: fix 'poll for write'/connected DGRAM socketsRainer Weikusat1-28/+24
For n:1 'datagram connections' (eg /dev/log), the unix_dgram_sendmsg routine implements a form of receiver-imposed flow control by comparing the length of the receive queue of the 'peer socket' with the max_ack_backlog value stored in the corresponding sock structure, either blocking the thread which caused the send-routine to be called or returning EAGAIN. This routine is used by both SOCK_DGRAM and SOCK_SEQPACKET sockets. The poll-implementation for these socket types is datagram_poll from core/datagram.c. A socket is deemed to be writeable by this routine when the memory presently consumed by datagrams owned by it is less than the configured socket send buffer size. This is always wrong for PF_UNIX non-stream sockets connected to server sockets dealing with (potentially) multiple clients if the abovementioned receive queue is currently considered to be full. 'poll' will then return, indicating that the socket is writeable, but a subsequent write result in EAGAIN, effectively causing an (usual) application to 'poll for writeability by repeated send request with O_NONBLOCK set' until it has consumed its time quantum. The change below uses a suitably modified variant of the datagram_poll routines for both type of PF_UNIX sockets, which tests if the recv-queue of the peer a socket is connected to is presently considered to be 'full' as part of the 'is this socket writeable'-checking code. The socket being polled is additionally put onto the peer_wait wait queue associated with its peer, because the unix_dgram_recvmsg routine does a wake up on this queue after a datagram was received and the 'other wakeup call' is done implicitly as part of skb destruction, meaning, a process blocked in poll because of a full peer receive queue could otherwise sleep forever if no datagram owned by its socket was already sitting on this queue. Among this change is a small (inline) helper routine named 'unix_recvq_full', which consolidates the actual testing code (in three different places) into a single location. Signed-off-by: Rainer Weikusat <rweikusat@mssgmbh.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-17af_unix: fix 'poll for write'/ connected DGRAM socketsRainer Weikusat1-9/+70
The unix_dgram_sendmsg routine implements a (somewhat crude) form of receiver-imposed flow control by comparing the length of the receive queue of the 'peer socket' with the max_ack_backlog value stored in the corresponding sock structure, either blocking the thread which caused the send-routine to be called or returning EAGAIN. This routine is used by both SOCK_DGRAM and SOCK_SEQPACKET sockets. The poll-implementation for these socket types is datagram_poll from core/datagram.c. A socket is deemed to be writeable by this routine when the memory presently consumed by datagrams owned by it is less than the configured socket send buffer size. This is always wrong for connected PF_UNIX non-stream sockets when the abovementioned receive queue is currently considered to be full. 'poll' will then return, indicating that the socket is writeable, but a subsequent write result in EAGAIN, effectively causing an (usual) application to 'poll for writeability by repeated send request with O_NONBLOCK set' until it has consumed its time quantum. The change below uses a suitably modified variant of the datagram_poll routines for both type of PF_UNIX sockets, which tests if the recv-queue of the peer a socket is connected to is presently considered to be 'full' as part of the 'is this socket writeable'-checking code. The socket being polled is additionally put onto the peer_wait wait queue associated with its peer, because the unix_dgram_sendmsg routine does a wake up on this queue after a datagram was received and the 'other wakeup call' is done implicitly as part of skb destruction, meaning, a process blocked in poll because of a full peer receive queue could otherwise sleep forever if no datagram owned by its socket was already sitting on this queue. Among this change is a small (inline) helper routine named 'unix_recvq_full', which consolidates the actual testing code (in three different places) into a single location. Signed-off-by: Rainer Weikusat <rweikusat@mssgmbh.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds1-1/+5
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (22 commits) tun: Multicast handling in tun_chr_ioctl() needs proper locking. [NET]: Fix heavy stack usage in seq_file output routines. [AF_UNIX] Initialise UNIX sockets before general device initcalls [RTNETLINK]: Fix bogus ASSERT_RTNL warning iwlwifi: Fix built-in compilation of iwlcore (part 2) tun: Fix minor race in TUNSETLINK ioctl handling. ppp_generic: use stats from net_device structure iwlwifi: Don't unlock priv->mutex if it isn't locked wireless: rndis_wlan: modparam_workaround_interval is never below 0. prism54: prism54_get_encode() test below 0 on unsigned index mac80211: update mesh EID values b43: Workaround DMA quirks mac80211: fix use before check of Qdisc length net/mac80211/rx.c: fix off-by-one mac80211: Fix race between ieee80211_rx_bss_put and lookup routines. ath5k: Fix radio identification on AR5424/2424 ssb: Fix all-ones boardflags b43: Add more btcoexist workarounds b43: Fix HostFlags data types b43: Workaround invalid bluetooth settings ...
2008-04-24[AF_UNIX] Initialise UNIX sockets before general device initcallsDavid Woodhouse1-1/+5
When drivers call request_module(), it tries to do something with UNIX sockets and triggers a 'runaway loop modprobe net-pf-1' warning. Avoid this by initialising AF_UNIX support earlier. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-19[PATCH] r/o bind mounts: get callers of vfs_mknod/create/mkdir()Dave Hansen1-0/+4
This takes care of all of the direct callers of vfs_mknod(). Since a few of these cases also handle normal file creation as well, this also covers some calls to vfs_create(). So that we don't have to make three mnt_want/drop_write() calls inside of the switch statement, we move some of its logic outside of the switch and into a helper function suggested by Christoph. This also encapsulates a fix for mknod(S_IFREG) that Miklos found. [AV: merged mkdir handling, added missing nfsd pieces] Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-12[AF_UNIX]: Use SEQ_START_TOKENJoe Perches1-3/+3
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[NET] NETNS: Omit namespace comparision without CONFIG_NET_NS.YOSHIFUJI Hideaki1-2/+2
Introduce an inline net_eq() to compare two namespaces. Without CONFIG_NET_NS, since no namespace other than &init_net exists, it is always 1. We do not need to convert 1) inline vs inline and 2) inline vs &init_net comparisons. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-26[NET] NETNS: Omit seq_net_private->net without CONFIG_NET_NS.YOSHIFUJI Hideaki1-5/+5
Without CONFIG_NET_NS, no namespace other than &init_net exists, no need to store net in seq_net_private. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-03-26[NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.YOSHIFUJI Hideaki1-10/+10
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>
2008-03-05net: replace remaining __FUNCTION__ occurrencesHarvey Harrison1-1/+1
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-14Introduce path_put()Jan Blunck1-3/+3
* Add path_put() functions for releasing a reference to the dentry and vfsmount of a struct path in the right order * Switch from path_release(nd) to path_put(&nd->path) * Rename dput_path() to path_put_conditional() [akpm@linux-foundation.org: fix cifs] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: <linux-fsdevel@vger.kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Steven French <sfrench@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14Embed a struct path into struct nameidata instead of nd->{dentry,mnt}Jan Blunck1-10/+10
This is the central patch of a cleanup series. In most cases there is no good reason why someone would want to use a dentry for itself. This series reflects that fact and embeds a struct path into nameidata. Together with the other patches of this series - it enforced the correct order of getting/releasing the reference count on <dentry,vfsmount> pairs - it prepares the VFS for stacking support since it is essential to have a struct path in every place where the stack can be traversed - it reduces the overall code size: without patch series: text data bss dec hex filename 5321639 858418 715768 6895825 6938d1 vmlinux with patch series: text data bss dec hex filename 5320026 858418 715768 6894212 693284 vmlinux This patch: Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix cifs] [akpm@linux-foundation.org: fix smack] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-28[NET]: Add some acquires/releases sparse annotations.Eric Dumazet1-0/+2
Add __acquires() and __releases() annotations to suppress some sparse warnings. example of warnings : net/ipv4/udp.c:1555:14: warning: context imbalance in 'udp_seq_start' - wrong count at exit net/ipv4/udp.c:1571:13: warning: context imbalance in 'udp_seq_stop' - unexpected unlock Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NETNS]: struct net content re-work (v3)Denis V. Lunev2-8/+8
Recently David Miller and Herbert Xu pointed out that struct net becomes overbloated and un-maintainable. There are two solutions: - provide a pointer to a network subsystem definition from struct net. This costs an additional dereferrence - place sub-system definition into the structure itself. This will speedup run-time access at the cost of recompilation time The second approach looks better for us. Other sub-systems will follow. Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[UNIX]: Make the unix sysctl tables per-namespacePavel Emelyanov2-8/+28
This is the core. * add the ctl_table_header on the struct net; * make the unix_sysctl_register and _unregister clone the table; * moves calls to them into per-net init and exit callbacks; * move the .data pointer in the proper place. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[UNIX]: Use ctl paths to register unix ctl tablesPavel Emelyanov1-19/+5
Unlike previous ones, this patch is useful by its own, as it decreases the vmlinux size :) But it will be used later, when the per-namespace sysctl is added. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[UNIX]: Move the sysctl_unix_max_dgram_qlenPavel Emelyanov2-4/+4
This will make all the sub-namespaces always use the default value (10) and leave the tuning via sysctl to the init namespace only. Per-namespace tuning is coming. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[UNIX]: Extend unix_sysctl_(un)register prototypesPavel Emelyanov2-4/+5
Add the struct net * argument to both of them to use in the future. Also make the register one return an error code. It is useless right now, but will make the future patches much simpler. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Name magic constants in sock_wake_async()Pavel Emelyanov1-4/+4
The sock_wake_async() performs a bit different actions depending on "how" argument. Unfortunately this argument ony has numerical magic values. I propose to give names to their constants to help people reading this function callers understand what's going on without looking into this function all the time. I suppose this is 2.6.25 material, but if it's not (or the naming seems poor/bad/awful), I can rework it against the current net-2.6 tree. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[UNIX] Move the unix sock iterators in to proper placePavel Emelyanov1-26/+23
The first_unix_socket() and next_unix_sockets() are now used in proc file and in forall_unix_socets macro only. The forall_unix_sockets is not used in this file at all so remove it. After this move the helpers to where they really belong, i.e. closer to proc code under the #ifdef CONFIG_PROC_FS option. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Consolidate net namespace related proc files creation.Denis V. Lunev1-25/+6
Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Make AF_UNIX per network namespace safe [v2]Denis V. Lunev1-26/+92
Because of the global nature of garbage collection, and because of the cost of per namespace hash tables unix_socket_table has been kept global. With a filter added on lookups so we don't see sockets from the wrong namespace. Currently I don't fold the namesapce into the hash so multiple namespaces using the same socket name will be guaranteed a hash collision. Changes from v1: - fixed unix_seq_open 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>
2007-11-29[UNIX]: EOF on non-blocking SOCK_SEQPACKETFlorian Zumbiehl1-1/+8
I am not absolutely sure whether this actually is a bug (as in: I've got no clue what the standards say or what other implementations do), but at least I was pretty surprised when I noticed that a recv() on a non-blocking unix domain socket of type SOCK_SEQPACKET (which is connection oriented, after all) where the remote end has closed the connection returned -1 (EAGAIN) rather than 0 to indicate end of file. This is a test case: | #include <sys/types.h> | #include <unistd.h> | #include <sys/socket.h> | #include <sys/un.h> | #include <fcntl.h> | #include <string.h> | #include <stdlib.h> | | int main(){ | int sock; | struct sockaddr_un addr; | char buf[4096]; | int pfds[2]; | | pipe(pfds); | sock=socket(PF_UNIX,SOCK_SEQPACKET,0); | addr.sun_family=AF_UNIX; | strcpy(addr.sun_path,"/tmp/foobar_testsock"); | bind(sock,(struct sockaddr *)&addr,sizeof(addr)); | listen(sock,1); | if(fork()){ | close(sock); | sock=socket(PF_UNIX,SOCK_SEQPACKET,0); | connect(sock,(struct sockaddr *)&addr,sizeof(addr)); | fcntl(sock,F_SETFL,fcntl(sock,F_GETFL)|O_NONBLOCK); | close(pfds[1]); | read(pfds[0],buf,sizeof(buf)); | recv(sock,buf,sizeof(buf),0); // <-- this one | }else accept(sock,NULL,NULL); | exit(0); | } If you try it, make sure /tmp/foobar_testsock doesn't exist. The marked recv() returns -1 (EAGAIN) on 2.6.23.9. Below you find a patch that fixes that. Signed-off-by: Florian Zumbiehl <florz@florz.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-11-10[UNIX]: The unix_nr_socks limit can be exceededPavel Emelyanov1-3/+4
The unix_nr_socks value is limited with the 2 * get_max_files() value, as seen from the unix_create1(). However, the check and the actual increment are separated with the GFP_KERNEL allocation, so this limit can be exceeded under a memory pressure - task may go to sleep freeing the pages and some other task will be allowed to allocate a new sock and so on and so forth. So make the increment before the check (similar thing is done in the sock_kmalloc) and go to kmalloc after this. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-10[AF_UNIX]: Convert socks to unix_socks in scan_inflight, not in callbacksPavel Emelyanov1-11/+9
The scan_inflight() routine scans through the unix sockets and calls some passed callback. The fact is that all these callbacks work with the unix_sock objects, not the sock ones, so make this conversion in the scan_inflight() before calling the callbacks. This removes one unneeded variable from the inc_inflight_move_tail(). Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-10[AF_UNIX]: Make unix_tot_inflight counter non-atomicPavel Emelyanov2-4/+4
This counter is _always_ modified under the unix_gc_lock spinlock, so its atomicity can be provided w/o additional efforts. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-01[NET]: Forget the zero_it argument of sk_alloc()Pavel Emelyanov1-1/+1
Finally, the zero_it argument can be completely removed from the callers and from the function prototype. Besides, fix the checkpatch.pl warnings about using the assignments inside if-s. This patch is rather big, and it is a part of the previous one. I splitted it wishing to make the patches more readable. Hope this particular split helped. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-19pid namespaces: changes to show virtual ids to userPavel Emelyanov1-3/+3
This is the largest patch in the set. Make all (I hope) the places where the pid is shown to or get from user operate on the virtual pids. The idea is: - all in-kernel data structures must store either struct pid itself or the pid's global nr, obtained with pid_nr() call; - when seeking the task from kernel code with the stored id one should use find_task_by_pid() call that works with global pids; - when showing pid's numerical value to the user the virtual one should be used, but however when one shows task's pid outside this task's namespace the global one is to be used; - when getting the pid from userspace one need to consider this as the virtual one and use appropriate task/pid-searching functions. [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: nuther build fix] [akpm@linux-foundation.org: yet nuther build fix] [akpm@linux-foundation.org: remove unneeded casts] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-15sched: affine sync wakeupsIngo Molnar1-2/+2
make sync wakeups affine for cache-cold tasks: if a cache-cold task is woken up by a sync wakeup then use the opportunity to migrate it straight away. (the two tasks are 'related' because they communicate) Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-10[NET]: Make core networking code use seq_open_privatePavel Emelyanov1-19/+1
This concerns the ipv4 and ipv6 code mostly, but also the netlink and unix sockets. The netlink code is an example of how to use the __seq_open_private() call - it saves the net namespace on this private. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make socket creation namespace safe.Eric W. Biederman1-5/+8
This patch passes in the namespace a new socket should be created in and has the socket code do the appropriate reference counting. By virtue of this all socket create methods are touched. In addition the socket create methods are modified so that they will fail if you attempt to create a socket in a non-default network namespace. Failing if we attempt to create a socket outside of the default network namespace ensures that as we incrementally make the network stack network namespace aware we will not export functionality that someone has not audited and made certain is network namespace safe. Allowing us to partially enable network namespaces before all of the exotic protocols are supported. Any protocol layers I have missed will fail to compile because I now pass an extra parameter into the socket creation code. [ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ] Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make /proc/net per network namespaceEric W. Biederman1-2/+3
This patch makes /proc/net per network namespace. It modifies the global variables proc_net and proc_net_stat to be per network namespace. The proc_net file helpers are modified to take a network namespace argument, and all of their callers are fixed to pass &init_net for that argument. This ensures that all of the /proc/net files are only visible and usable in the initial network namespace until the code behind them has been updated to be handle multiple network namespaces. Making /proc/net per namespace is necessary as at least some files in /proc/net depend upon the set of network devices which is per network namespace, and even more files in /proc/net have contents that are relevant to a single network namespace. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-31[AF_UNIX]: Make code static.Adrian Bunk1-2/+28
The following code can now become static: - struct unix_socket_table - unix_table_lock Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-11[AF_UNIX]: Rewrite garbage collector, fixes race.Miklos Szeredi2-143/+188
Throw out the old mark & sweep garbage collector and put in a refcounting cycle detecting one. The old one had a race with recvmsg, that resulted in false positives and hence data loss. The old algorithm operated on all unix sockets in the system, so any additional locking would have meant performance problems for all users of these. The new algorithm instead only operates on "in flight" sockets, which are very rare, and the additional locking for these doesn't negatively impact the vast majority of users. In fact it's probable, that there weren't *any* heavy senders of sockets over sockets, otherwise the above race would have been discovered long ago. The patch works OK with the app that exposed the race with the old code. The garbage collection has also been verified to work in a few simple cases. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10[NET]: Make all initialized struct seq_operations const.Philippe De Muyter1-1/+1
Make all initialized struct seq_operations in net/ const Signed-off-by: Philippe De Muyter <phdm@macqel.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-07[AF_UNIX]: Fix stream recvmsg() race.Miklos Szeredi1-3/+10
A recv() on an AF_UNIX, SOCK_STREAM socket can race with a send()+close() on the peer, causing recv() to return zero, even though the sent data should be received. This happens if the send() and the close() is performed between skb_dequeue() and checking sk->sk_shutdown in unix_stream_recvmsg(): process A skb_dequeue() returns NULL, there's no data in the socket queue process B new data is inserted onto the queue by unix_stream_sendmsg() process B sk->sk_shutdown is set to SHUTDOWN_MASK by unix_release_sock() process A sk->sk_shutdown is checked, unix_release_sock() returns zero I'm surprised nobody noticed this, it's not hard to trigger. Maybe it's just (un)luck with the timing. It's possible to work around this bug in userspace, by retrying the recv() once in case of a zero return value. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-03[AF_UNIX]: Fix datagram connect race causing an OOPS.David S. Miller1-5/+38
Based upon an excellent bug report and initial patch by Frederik Deweerdt. The UNIX datagram connect code blindly dereferences other->sk_socket via the call down to the security_unix_may_send() function. Without locking 'other' that pointer can go NULL via unix_release_sock() which does sock_orphan() which also marks the socket SOCK_DEAD. So we have to lock both 'sk' and 'other' yet avoid all kinds of potential deadlocks (connect to self is OK for datagram sockets and it is possible for two datagram sockets to perform a simultaneous connect to each other). So what we do is have a "double lock" function similar to how we handle this situation in other areas of the kernel. We take the lock of the socket pointer with the smallest address first in order to avoid ABBA style deadlocks. Once we have them both locked, we check to see if SOCK_DEAD is set for 'other' and if so, drop everything and retry the lookup. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-03[AF_UNIX]: Make socket locking much less confusing.David S. Miller1-47/+47
The unix_state_*() locking macros imply that there is some rwlock kind of thing going on, but the implementation is actually a spinlock which makes the code more confusing than it needs to be. So use plain unix_state_lock and unix_state_unlock. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap1-1/+0
Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-25[SK_BUFF]: Introduce skb_reset_transport_header(skb)Arnaldo Carvalho de Melo1-1/+1
For the common, open coded 'skb->h.raw = skb->data' operation, so that we can later turn skb->h.raw into a offset, reducing the size of struct sk_buff in 64bit land while possibly keeping it as a pointer on 32bit. This one touches just the most simple cases: skb->h.raw = skb->data; skb->h.raw = {skb_push|[__]skb_pull}() The next ones will handle the slightly more "complex" cases. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-06[NET]: Revert incorrect accept queue backlog changes.David S. Miller1-3/+3
This reverts two changes: 8488df894d05d6fa41c2bd298c335f944bb0e401 248f06726e866942b3d8ca8f411f9067713b7ff8 A backlog value of N really does mean allow "N + 1" connections to queue to a listening socket. This allows one to specify "0" as the backlog and still get 1 connection. Noticed by Gerrit Renker and Rick Jones. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-02[AF_UNIX]: Test against sk_max_ack_backlog properly.David S. Miller1-3/+3
This brings things inline with the sk_acceptq_is_full() bug fix. The limit test should be x >= sk_max_ack_backlog. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-14[PATCH] sysctl: remove insert_at_head from register_sysctlEric W. Biederman1-1/+1
The semantic effect of insert_at_head is that it would allow new registered sysctl entries to override existing sysctl entries of the same name. Which is pain for caching and the proc interface never implemented. I have done an audit and discovered that none of the current users of register_sysctl care as (excpet for directories) they do not register duplicate sysctl entries. So this patch simply removes the support for overriding existing entries in the sys_sysctl interface since no one uses it or cares and it makes future enhancments harder. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Howells <dhowells@redhat.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Andi Kleen <ak@muc.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Corey Minyard <minyard@acm.org> Cc: Neil Brown <neilb@suse.de> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Jan Kara <jack@ucw.cz> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Mark Fasheh <mark.fasheh@oracle.com> Cc: David Chinner <dgc@sgi.com> 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>
2007-02-14[PATCH] remove many unneeded #includes of sched.hTim Schmielau1-1/+0
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>
2007-02-12[PATCH] mark struct file_operations const 8Arjan van de Ven1-1/+1
Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10[NET] UNIX: Fix whitespace errors.YOSHIFUJI Hideaki2-30/+30
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-08[PATCH] struct path: convert unixJosef Sipek1-1/+1
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-02[NET]: Annotate csum_partial() callers in net/*Al Viro1-1/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[AF_UNIX]: Change max_dgram_qlen sysctl to __read_mostlyBrian Haley1-1/+1
Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[NET]: Use BUILD_BUG_ON() for checking size of skb->cb.YOSHIFUJI Hideaki1-4/+1
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>