summaryrefslogtreecommitdiff
path: root/net/unix/af_unix.c
AgeCommit message (Collapse)AuthorFilesLines
2016-09-04af_unix: split 'u->readlock' into two: 'iolock' and 'bindlock'Linus Torvalds1-22/+23
Right now we use the 'readlock' both for protecting some of the af_unix IO path and for making the bind be single-threaded. The two are independent, but using the same lock makes for a nasty deadlock due to ordering with regards to filesystem locking. The bind locking would want to nest outside the VSF pathname locking, but the IO locking wants to nest inside some of those same locks. We tried to fix this earlier with commit c845acb324aa ("af_unix: Fix splice-bind deadlock") which moved the readlock inside the vfs locks, but that caused problems with overlayfs that will then call back into filesystem routines that take the lock in the wrong order anyway. Splitting the locks means that we can go back to having the bind lock be the outermost lock, and we don't have any deadlocks with lock ordering. Acked-by: Rainer Weikusat <rweikusat@cyberadapt.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04Revert "af_unix: Fix splice-bind deadlock"Linus Torvalds1-40/+26
This reverts commit c845acb324aa85a39650a14e7696982ceea75dc1. It turns out that it just replaces one deadlock with another one: we can still get the wrong lock ordering with the readlock due to overlayfs calling back into the filesystem layer and still taking the vfs locks after the readlock. The proper solution ends up being to just split the readlock into two pieces: the bind lock (taken *outside* the vfs locks) and the IO lock (taken *inside* the filesystem locks). The two locks are independent anyway. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-26af_unix: charge buffers to kmemcgVladimir Davydov1-0/+1
Unix sockets can consume a significant amount of system memory, hence they should be accounted to kmemcg. Since unix socket buffers are always allocated from process context, all we need to do to charge them to kmemcg is set __GFP_ACCOUNT in sock->sk_allocation mask. Eric asked: > 1) What happens when a buffer, allocated from socket <A> lands in a > different socket <B>, maybe owned by another user/process. > > Who owns it now, in term of kmemcg accounting ? We never move memcg charges. E.g. if two processes from different cgroups are sharing a memory region, each page will be charged to the process which touched it first. Or if two processes are working with the same directory tree, inodes and dentries will be charged to the first user. The same is fair for unix socket buffers - they will be charged to the sender. > 2) Has performance impact been evaluated ? I ran netperf STREAM_STREAM with default options in a kmemcg on a 4 core x2 HT box. The results are below: # clients bandwidth (10^6bits/sec) base patched 1 67643 +- 725 64874 +- 353 - 4.0 % 4 193585 +- 2516 186715 +- 1460 - 3.5 % 8 194820 +- 377 187443 +- 1229 - 3.7 % So the accounting doesn't come for free - it takes ~4% of performance. I believe we could optimize it by using per cpu batching not only on charge, but also on uncharge in memcg core, but that's beyond the scope of this patch set - I'll take a look at this later. Anyway, if performance impact is found to be unacceptable, it is always possible to disable kmem accounting at boot time (cgroup.memory=nokmem) or not use memory cgroups at runtime at all (thanks to jump labels there'll be no overhead even if they are compiled in). Link: http://lkml.kernel.org/r/fcfe6cae27a59fbc5e40145664b3cf085a560c68.1464079538.git.vdavydov@virtuozzo.com Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-12Merge branch 'overlayfs-af_unix-fix' into overlayfs-linusMiklos Szeredi1-3/+3
2016-05-20af_unix: fix hard linked sockets on overlayMiklos Szeredi1-3/+3
Overlayfs uses separate inodes even in the case of hard links on the underlying filesystems. This is a problem for AF_UNIX socket implementation which indexes sockets based on the inode. This resulted in hard linked sockets not working. The fix is to use the real, underlying inode. Test case follows: -- ovl-sock-test.c -- #include <unistd.h> #include <err.h> #include <sys/socket.h> #include <sys/un.h> #define SOCK "test-sock" #define SOCK2 "test-sock2" int main(void) { int fd, fd2; struct sockaddr_un addr = { .sun_family = AF_UNIX, .sun_path = SOCK, }; struct sockaddr_un addr2 = { .sun_family = AF_UNIX, .sun_path = SOCK2, }; unlink(SOCK); unlink(SOCK2); if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) err(1, "socket"); if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1) err(1, "bind"); if (listen(fd, 0) == -1) err(1, "listen"); if (link(SOCK, SOCK2) == -1) err(1, "link"); if ((fd2 = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) err(1, "socket"); if (connect(fd2, (struct sockaddr *) &addr2, sizeof(addr2)) == -1) err (1, "connect"); return 0; } ---- Reported-by: Alexander Morozov <alexandr.morozov@docker.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org>
2016-03-28constify security_path_{mkdir,mknod,symlink}Al Viro1-1/+1
... as well as unix_mknod() and may_o_create() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-02-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-10/+20
Conflicts: drivers/net/phy/bcm7xxx.c drivers/net/phy/marvell.c drivers/net/vxlan.c All three conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-19af_unix: Don't use continue to re-execute unix_stream_read_generic loopRainer Weikusat1-1/+2
The unix_stream_read_generic function tries to use a continue statement to restart the receive loop after waiting for a message. This may not work as intended as the caller might use a recvmsg call to peek at control messages without specifying a message buffer. If this was the case, the continue will cause the function to return without an error and without the credential information if the function had to wait for a message while it had returned with the credentials otherwise. Change to using goto to restart the loop without checking the condition first in this case so that credentials are returned either way. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16af_unix: Guard against other == sk in unix_dgram_sendmsgRainer Weikusat1-1/+6
The unix_dgram_sendmsg routine use the following test if (unlikely(unix_peer(other) != sk && unix_recvq_full(other))) { to determine if sk and other are in an n:1 association (either established via connect or by using sendto to send messages to an unrelated socket identified by address). This isn't correct as the specified address could have been bound to the sending socket itself or because this socket could have been connected to itself by the time of the unix_peer_get but disconnected before the unix_state_lock(other). In both cases, the if-block would be entered despite other == sk which might either block the sender unintentionally or lead to trying to unlock the same spin lock twice for a non-blocking send. Add a other != sk check to guard against this. Fixes: 7d267278a9ec ("unix: avoid use-after-free in ep_remove_wait_queue") Reported-By: Philipp Hahn <pmhahn@pmhahn.de> Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Tested-by: Philipp Hahn <pmhahn@pmhahn.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16af_unix: Don't set err in unix_stream_read_generic unless there was an errorRainer Weikusat1-6/+10
The present unix_stream_read_generic contains various code sequences of the form err = -EDISASTER; if (<test>) goto out; This has the unfortunate side effect of possibly causing the error code to bleed through to the final out: return copied ? : err; and then to be wrongly returned if no data was copied because the caller didn't supply a data buffer, as demonstrated by the program available at http://pad.lv/1540731 Change it such that err is only set if an error condition was detected. Fixes: 3822b5c2fc62 ("af_unix: Revert 'lock_interruptible' in stream receive code") Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com> Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-08unix: correctly track in-flight fds in sending process user_structHannes Frederic Sowa1-2/+2
The commit referenced in the Fixes tag incorrectly accounted the number of in-flight fds over a unix domain socket to the original opener of the file-descriptor. This allows another process to arbitrary deplete the original file-openers resource limit for the maximum of open files. Instead the sending processes and its struct cred should be credited. To do so, we add a reference counted struct user_struct pointer to the scm_fp_list and use it to account for the number of inflight unix fds. Fixes: 712f4aad406bb1 ("unix: properly account for FDs passed over unix sockets") Reported-by: David Herrmann <dh.herrmann@gmail.com> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-07net: drop write-only stack variableDavid Herrmann1-4/+1
Remove a write-only stack variable from unix_attach_fds(). This is a left-over from the security fix in: commit 712f4aad406bb1ed67f3f98d04c044191f0ff593 Author: willy tarreau <w@1wt.eu> Date: Sun Jan 10 07:54:56 2016 +0100 unix: properly account for FDs passed over unix sockets Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-24af_unix: fix struct pid memory leakEric Dumazet1-0/+1
Dmitry reported a struct pid leak detected by a syzkaller program. Bug happens in unix_stream_recvmsg() when we break the loop when a signal is pending, without properly releasing scm. Fixes: b3ca9b02b007 ("net: fix multithreaded signal handling in unix recv routines") Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+20
Conflicts: drivers/net/bonding/bond_main.c drivers/net/ethernet/mellanox/mlxsw/spectrum.h drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c The bond_main.c and mellanox switch conflicts were cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-11unix: properly account for FDs passed over unix socketswilly tarreau1-4/+20
It is possible for a process to allocate and accumulate far more FDs than the process' limit by sending them over a unix socket then closing them to keep the process' fd count low. This change addresses this problem by keeping track of the number of FDs in flight per user and preventing non-privileged processes from having more FDs in flight than their configured FD limit. Reported-by: socketpair@gmail.com Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Mitigates: CVE-2013-4312 (Linux 2.0+) Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-26/+40
2016-01-04af_unix: Fix splice-bind deadlockRainer Weikusat1-26/+40
On 2015/11/06, Dmitry Vyukov reported a deadlock involving the splice system call and AF_UNIX sockets, http://lists.openwall.net/netdev/2015/11/06/24 The situation was analyzed as (a while ago) A: socketpair() B: splice() from a pipe to /mnt/regular_file does sb_start_write() on /mnt C: try to freeze /mnt wait for B to finish with /mnt A: bind() try to bind our socket to /mnt/new_socket_name lock our socket, see it not bound yet decide that it needs to create something in /mnt try to do sb_start_write() on /mnt, block (it's waiting for C). D: splice() from the same pipe to our socket lock the pipe, see that socket is connected try to lock the socket, block waiting for A B: get around to actually feeding a chunk from pipe to file, try to lock the pipe. Deadlock. on 2015/11/10 by Al Viro, http://lists.openwall.net/netdev/2015/11/10/4 The patch fixes this by removing the kern_path_create related code from unix_mknod and executing it as part of unix_bind prior acquiring the readlock of the socket in question. This means that A (as used above) will sb_start_write on /mnt before it acquires the readlock, hence, it won't indirectly block B which first did a sb_start_write and then waited for a thread trying to acquire the readlock. Consequently, A being blocked by C waiting for B won't cause a deadlock anymore (effectively, both A and B acquire two locks in opposite order in the situation described above). Dmitry Vyukov(<dvyukov@google.com>) tested the original patch. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-10/+3
Conflicts: drivers/net/geneve.c Here we had an overlapping change, where in 'net' the extraneous stats bump was being removed whilst in 'net-next' the final argument to udp_tunnel6_xmit_skb() was being changed. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-17af_unix: Revert 'lock_interruptible' in stream receive codeRainer Weikusat1-10/+3
With b3ca9b02b00704053a38bfe4c31dbbb9c13595d0, the AF_UNIX SOCK_STREAM receive code was changed from using mutex_lock(&u->readlock) to mutex_lock_interruptible(&u->readlock) to prevent signals from being delayed for an indefinite time if a thread sleeping on the mutex happened to be selected for handling the signal. But this was never a problem with the stream receive code (as opposed to its datagram counterpart) as that never went to sleep waiting for new messages with the mutex held and thus, wouldn't cause secondary readers to block on the mutex waiting for the sleeping primary reader. As the interruptible locking makes the code more complicated in exchange for no benefit, change it back to using mutex_lock. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-06af_unix: fix unix_dgram_recvmsg entry lockingRainer Weikusat1-15/+20
The current unix_dgram_recvsmg code acquires the u->readlock mutex in order to protect access to the peek offset prior to calling __skb_recv_datagram for actually receiving data. This implies that a blocking reader will go to sleep with this mutex held if there's presently no data to return to userspace. Two non-desirable side effects of this are that a later non-blocking read call on the same socket will block on the ->readlock mutex until the earlier blocking call releases it (or the readers is interrupted) and that later blocking read calls will wait longer than the effective socket read timeout says they should: The timeout will only start 'ticking' once such a reader hits the schedule_timeout in wait_for_more_packets (core.c) while the time it already had to wait until it could acquire the mutex is unaccounted for. The patch avoids both by using the __skb_try_recv_datagram and __skb_wait_for_more packets functions created by the first patch to implement a unix_dgram_recvmsg read loop which releases the readlock mutex prior to going to sleep and reacquires it as needed afterwards. Non-blocking readers will thus immediately return with -EAGAIN if there's no data available regardless of any concurrent blocking readers and all blocking readers will end up sleeping via schedule_timeout, thus honouring the configured socket receive timeout. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-37/+231
Conflicts: drivers/net/ethernet/renesas/ravb_main.c kernel/bpf/syscall.c net/ipv4/ipmr.c All three conflicts were cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-01net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATAEric Dumazet1-3/+3
This patch is a cleanup to make following patch easier to review. Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA from (struct socket)->flags to a (struct socket_wq)->flags to benefit from RCU protection in sock_wake_async() To ease backports, we rename both constants. Two new helpers, sk_set_bit(int nr, struct sock *sk) and sk_clear_bit(int net, struct sock *sk) are added so that following patch can change their implementation. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-01unix: use wq_has_sleeper in unix_dgram_recvmsgRainer Weikusat1-2/+4
The current unix_dgram_recvmsg does a wake up for every received datagram. This seems wasteful as only SOCK_DGRAM client sockets in an n:1 association with a server socket will ever wait because of the associated condition. The patch below changes the function such that the wake up only happens if wq_has_sleeper indicates that someone actually wants to be notified. Testing with SOCK_SEQPACKET and SOCK_DGRAM socket seems to confirm that this is an improvment. Signed-Off-By: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-30af-unix: passcred support for sendpageHannes Frederic Sowa1-15/+64
sendpage did not care about credentials at all. This could lead to situations in which because of fd passing between processes we could append data to skbs with different scm data. It is illegal to splice those skbs together. Instead we have to allocate a new skb and if requested fill out the scm details. Fixes: 869e7c62486ec ("net: af_unix: implement stream sendpage support") Reported-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-30net: Generalise wq_has_sleeper helperHerbert Xu1-1/+1
The memory barrier in the helper wq_has_sleeper is needed by just about every user of waitqueue_active. This patch generalises it by making it take a wait_queue_head_t directly. The existing helper is renamed to skwq_has_sleeper. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-23unix: avoid use-after-free in ep_remove_wait_queueRainer Weikusat1-19/+164
Rainer Weikusat <rweikusat@mobileactivedefense.com> writes: An AF_UNIX datagram socket being the client in an n:1 association with some server socket is only allowed to send messages to the server if the receive queue of this socket contains at most sk_max_ack_backlog datagrams. This implies that prospective writers might be forced to go to sleep despite none of the message presently enqueued on the server receive queue were sent by them. In order to ensure that these will be woken up once space becomes again available, the present unix_dgram_poll routine does a second sock_poll_wait call with the peer_wait wait queue of the server socket as queue argument (unix_dgram_recvmsg does a wake up on this queue after a datagram was received). This is inherently problematic because the server socket is only guaranteed to remain alive for as long as the client still holds a reference to it. In case the connection is dissolved via connect or by the dead peer detection logic in unix_dgram_sendmsg, the server socket may be freed despite "the polling mechanism" (in particular, epoll) still has a pointer to the corresponding peer_wait queue. There's no way to forcibly deregister a wait queue with epoll. Based on an idea by Jason Baron, the patch below changes the code such that a wait_queue_t belonging to the client socket is enqueued on the peer_wait queue of the server whenever the peer receive queue full condition is detected by either a sendmsg or a poll. A wake up on the peer queue is then relayed to the ordinary wait queue of the client socket via wake function. The connection to the peer wait queue is again dissolved if either a wake up is about to be relayed or the client socket reconnects or a dead peer is detected or the client socket is itself closed. This enables removing the second sock_poll_wait from unix_dgram_poll, thus avoiding the use-after-free, while still ensuring that no blocked writer sleeps forever. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Fixes: ec0d215f9420 ("af_unix: fix 'poll for write'/connected DGRAM sockets") Reviewed-by: Jason Baron <jbaron@akamai.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17af_unix: take receive queue lock while appending new skbHannes Frederic Sowa1-1/+4
While possibly in future we don't necessarily need to use sk_buff_head.lock this is a rather larger change, as it affects the af_unix fd garbage collector, diag and socket cleanups. This is too much for a stable patch. For the time being grab sk_buff_head.lock without disabling bh and irqs, so don't use locked skb_queue_tail. Fixes: 869e7c62486e ("net: af_unix: implement stream sendpage support") Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Reported-by: Eric Dumazet <edumazet@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-16af_unix: don't append consumed skbs to sk_receive_queueHannes Frederic Sowa1-0/+1
In case multiple writes to a unix stream socket race we could end up in a situation where we pre-allocate a new skb for use in unix_stream_sendpage but have to free it again in the locked section because another skb has been appended meanwhile, which we must use. Accidentally we didn't clear the pointer after consuming it and so we touched freed memory while appending it to the sk_receive_queue. So, clear the pointer after consuming the skb. This bug has been found with syzkaller (http://github.com/google/syzkaller) by Dmitry Vyukov. Fixes: 869e7c62486e ("net: af_unix: implement stream sendpage support") Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-15af-unix: fix use-after-free with concurrent readers while splicingHannes Frederic Sowa1-0/+18
During splicing an af-unix socket to a pipe we have to drop all af-unix socket locks. While doing so we allow another reader to enter unix_stream_read_generic which can read, copy and finally free another skb. If exactly this skb is just in process of being spliced we get a use-after-free report by kasan. First, we must make sure to not have a free while the skb is used during the splice operation. We simply increment its use counter before unlocking the reader lock. Stream sockets have the nice characteristic that we don't care about zero length writes and they never reach the peer socket's queue. That said, we can take the UNIXCB.consumed field as the indicator if the skb was already freed from the socket's receive queue. If the skb was fully consumed after we locked the reader side again we know it has been dropped by a second reader. We indicate a short read to user space and abort the current splice operation. This bug has been found with syzkaller (http://github.com/google/syzkaller) by Dmitry Vyukov. Fixes: 2b514574f7e8 ("net: af_unix: implement splice for stream af_unix sockets") Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-25af_unix: do not report POLLOUT on listenersEric Dumazet1-2/+3
poll(POLLOUT) on a listener should not report fd is ready for a write(). This would break some applications using poll() and pfd.events = -1, as they would not block in poll() Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Alan Burlison <Alan.Burlison@oracle.com> Tested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05net/unix: fix logic about sk_peek_offsetAndrey Vagin1-5/+7
Now send with MSG_PEEK can return data from multiple SKBs. Unfortunately we take into account the peek offset for each skb, that is wrong. We need to apply the peek offset only once. In addition, the peek offset should be used only if MSG_PEEK is set. Cc: "David S. Miller" <davem@davemloft.net> (maintainer:NETWORKING Cc: Eric Dumazet <edumazet@google.com> (commit_signer:1/14=7%) Cc: Aaron Conole <aconole@bytheb.org> Fixes: 9f389e35674f ("af_unix: return data from multiple SKBs on recv() with MSG_PEEK flag") Signed-off-by: Andrey Vagin <avagin@openvz.org> Tested-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29af_unix: return data from multiple SKBs on recv() with MSG_PEEK flagAaron Conole1-1/+14
AF_UNIX sockets now return multiple skbs from recv() when MSG_PEEK flag is set. This is referenced in kernel bugzilla #12323 @ https://bugzilla.kernel.org/show_bug.cgi?id=12323 As described both in the BZ and lkml thread @ http://lkml.org/lkml/2008/1/8/444 calling recv() with MSG_PEEK on an AF_UNIX socket only reads a single skb, where the desired effect is to return as much skb data has been queued, until hitting the recv buffer size (whichever comes first). The modified MSG_PEEK path will now move to the next skb in the tree and jump to the again: label, rather than following the natural loop structure. This requires duplicating some of the loop head actions. This was tested using the python socketpair python code attached to the bugzilla issue. Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-10net/unix: support SCM_SECURITY for stream socketsStephen Smalley1-4/+16
SCM_SECURITY was originally only implemented for datagram sockets, not for stream sockets. However, SCM_CREDENTIALS is supported on Unix stream sockets. For consistency, implement Unix stream support for SCM_SECURITY as well. Also clean up the existing code and get rid of the superfluous UNIXSID macro. Motivated by https://bugzilla.redhat.com/show_bug.cgi?id=1224211, where systemd was using SCM_CREDENTIALS and assumed wrongly that SCM_SECURITY was also supported on Unix stream sockets. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+8
Conflicts: drivers/net/phy/amd-xgbe-phy.c drivers/net/wireless/iwlwifi/Kconfig include/net/mac80211.h iwlwifi/Kconfig and mac80211.h were both trivial overlapping changes. The drivers/net/phy/amd-xgbe-phy.c file got removed in 'net-next' and the bug fix that happened on the 'net' side is already integrated into the rest of the amd-xgbe driver. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-26unix/caif: sk_socket can disappear when state is unlockedMark Salyzyn1-0/+8
got a rare NULL pointer dereference in clear_bit Signed-off-by: Mark Salyzyn <salyzyn@android.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> ---- v2: switch to sock_flag(sk, SOCK_DEAD) and added net/caif/caif_socket.c v3: return -ECONNRESET in upstream caller of wait function for SOCK_DEAD Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-25net: af_unix: implement splice for stream af_unix socketsHannes Frederic Sowa1-21/+119
unix_stream_recvmsg is refactored to unix_stream_read_generic in this patch and enhanced to deal with pipe splicing. The refactoring is inneglible, we mostly have to deal with a non-existing struct msghdr argument. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-25net: af_unix: implement stream sendpage supportHannes Frederic Sowa1-1/+98
This patch implements sendpage support for AF_UNIX SOCK_STREAM sockets. This is also required for a complete splice implementation. The implementation is a bit tricky because we append to already existing skbs and so have to hold unix_sk->readlock to protect the reading side from either advancing UNIXCB.consumed or freeing the skb at the socket receive tail. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11net: Pass kern from net_proto_family.create to sk_allocEric W. Biederman1-4/+4
In preparation for changing how struct net is refcounted on kernel sockets pass the knowledge that we are creating a kernel socket from sock_create_kern through to sk_alloc. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-15VFS: net/unix: d_backing_inode() annotationsDavid Howells1-3/+3
places where we are dealing with S_ISSOCK file creation/lookups. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15VFS: AF_UNIX sockets should call mknod on the top layer onlyDavid Howells1-1/+1
AF_UNIX sockets should call mknod on the top layer only and should not attempt to modify the lower layer in a layered filesystem such as overlayfs. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-02net: Remove iocb argument from sendmsg and recvmsgYing Xue1-29/+21
After TIPC doesn't depend on iocb argument in its internal implementations of sendmsg() and recvmsg() hooks defined in proto structure, no any user is using iocb argument in them at all now. Then we can drop the redundant iocb argument completely from kinds of implementations of both sendmsg() and recvmsg() in the entire networking stack. Cc: Christoph Hellwig <hch@lst.de> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-28net: remove sock_iocbChristoph Hellwig1-44/+29
The sock_iocb structure is allocate on stack for each read/write-like operation on sockets, and contains various fields of which only the embedded msghdr and sometimes a pointer to the scm_cookie is ever used. Get rid of the sock_iocb and put a msghdr directly on the stack and pass the scm_cookie explicitly to netlink_mmap_sendmsg. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09put iov_iter into msghdrAl Viro1-8/+2
Note that the code _using_ ->msg_iter at that point will be very unhappy with anything other than unshifted iovec-backed iov_iter. We still need to convert users to proper primitives. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24switch AF_PACKET and AF_UNIX to skb_copy_datagram_from_iter()Al Viro1-3/+8
... and kill skb_copy_datagram_iovec() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-05net: Add and use skb_copy_datagram_msg() helper.David S. Miller1-3/+3
This encapsulates all of the skb_copy_datagram_iovec() callers with call argument signature "skb, offset, msghdr->msg_iov, length". When we move to iov_iters in the networking, the iov_iter object will sit in the msghdr. Having a helper like this means there will be less places to touch during that transformation. Based upon descriptions and patch from Al Viro. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-1/+7
Pull networking updates from David Miller: 1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov. 2) Multiqueue support in xen-netback and xen-netfront, from Andrew J Benniston. 3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn Mork. 4) BPF now has a "random" opcode, from Chema Gonzalez. 5) Add more BPF documentation and improve test framework, from Daniel Borkmann. 6) Support TCP fastopen over ipv6, from Daniel Lee. 7) Add software TSO helper functions and use them to support software TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia. 8) Support software TSO in fec driver too, from Nimrod Andy. 9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli. 10) Handle broadcasts more gracefully over macvlan when there are large numbers of interfaces configured, from Herbert Xu. 11) Allow more control over fwmark used for non-socket based responses, from Lorenzo Colitti. 12) Do TCP congestion window limiting based upon measurements, from Neal Cardwell. 13) Support busy polling in SCTP, from Neal Horman. 14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru. 15) Bridge promisc mode handling improvements from Vlad Yasevich. 16) Don't use inetpeer entries to implement ID generation any more, it performs poorly, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits) rtnetlink: fix userspace API breakage for iproute2 < v3.9.0 tcp: fixing TLP's FIN recovery net: fec: Add software TSO support net: fec: Add Scatter/gather support net: fec: Increase buffer descriptor entry number net: fec: Factorize feature setting net: fec: Enable IP header hardware checksum net: fec: Factorize the .xmit transmit function bridge: fix compile error when compiling without IPv6 support bridge: fix smatch warning / potential null pointer dereference via-rhine: fix full-duplex with autoneg disable bnx2x: Enlarge the dorq threshold for VFs bnx2x: Check for UNDI in uncommon branch bnx2x: Fix 1G-baseT link bnx2x: Fix link for KR with swapped polarity lane sctp: Fix sk_ack_backlog wrap-around problem net/core: Add VF link state control policy net/fsl: xgmac_mdio is dependent on OF_MDIO net/fsl: Make xgmac_mdio read error message useful net_sched: drr: warn when qdisc is not work conserving ...
2014-05-16net: unix: Align send data_len up to PAGE_SIZEKirill Tkhai1-1/+7
Using whole of allocated pages reduces requested skb->data size. This is just a little more thriftily allocation. netperf does not show difference with the current performance. Signed-off-by: Kirill Tkhai <ktkhai@parallels.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-18arch: Mass conversion of smp_mb__*()Peter Zijlstra1-1/+1
Mostly scripted conversion of the smp_mb__* barriers. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-11net: Fix use after free by removing length arg from sk_data_ready callbacks.David S. Miller1-3/+3
Several spots in the kernel perform a sequence like: skb_queue_tail(&sk->s_receive_queue, skb); sk->sk_data_ready(sk, skb->len); But at the moment we place the SKB onto the socket receive queue it can be consumed and freed up. So this skb->len access is potentially to freed up memory. Furthermore, the skb->len can be modified by the consumer so it is possible that the value isn't accurate. And finally, no actual implementation of this callback actually uses the length argument. And since nobody actually cared about it's value, lots of call sites pass arbitrary values in such as '0' and even '1'. So just remove the length argument from the callback, that way there is no confusion whatsoever and all of these use-after-free cases get fixed as a side effect. Based upon a patch by Eric Dumazet and his suggestion to audit this issue tree-wide. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-26net: unix: non blocking recvmsg() should not return -EINTREric Dumazet1-5/+12
Some applications didn't expect recvmsg() on a non blocking socket could return -EINTR. This possibility was added as a side effect of commit b3ca9b02b00704 ("net: fix multithreaded signal handling in unix recv routines"). To hit this bug, you need to be a bit unlucky, as the u->readlock mutex is usually held for very small periods. Fixes: b3ca9b02b00704 ("net: fix multithreaded signal handling in unix recv routines") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>