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* net: convert %p usage to %pKDan Rosenberg2011-05-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". The supporting code for kptr_restrict and %pK are currently in the -mm tree. This patch converts users of %p in net/ to %pK. Cases of printing pointers to the syslog are not covered, since this would eliminate useful information for postmortem debugging and the reading of the syslog is already optionally protected by the dmesg_restrict sysctl. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: Only allow recv on connected seqpacket sockets.Eric W. Biederman2011-05-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes the following oops discovered by Dan Aloni: > Anyway, the following is the output of the Oops that I got on the > Ubuntu kernel on which I first detected the problem > (2.6.37-12-generic). The Oops that followed will be more useful, I > guess. >[ 5594.669852] BUG: unable to handle kernel NULL pointer dereference > at           (null) > [ 5594.681606] IP: [<ffffffff81550b7b>] unix_dgram_recvmsg+0x1fb/0x420 > [ 5594.687576] PGD 2a05d067 PUD 2b951067 PMD 0 > [ 5594.693720] Oops: 0002 [#1] SMP > [ 5594.699888] last sysfs file: The bug was that unix domain sockets use a pseduo packet for connecting and accept uses that psudo packet to get the socket. In the buggy seqpacket case we were allowing unconnected sockets to call recvmsg and try to receive the pseudo packet. That is always wrong and as of commit 7361c36c5 the pseudo packet had become enough different from a normal packet that the kernel started oopsing. Do for seqpacket_recv what was done for seqpacket_send in 2.5 and only allow it on connected seqpacket sockets. Cc: stable@kernel.org Tested-by: Dan Aloni <dan@aloni.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Fix common misspellingsLucas De Marchi2011-03-31
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds2011-03-16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1480 commits) bonding: enable netpoll without checking link status xfrm: Refcount destination entry on xfrm_lookup net: introduce rx_handler results and logic around that bonding: get rid of IFF_SLAVE_INACTIVE netdev->priv_flag bonding: wrap slave state work net: get rid of multiple bond-related netdevice->priv_flags bonding: register slave pointer for rx_handler be2net: Bump up the version number be2net: Copyright notice change. Update to Emulex instead of ServerEngines e1000e: fix kconfig for crc32 dependency netfilter ebtables: fix xt_AUDIT to work with ebtables xen network backend driver bonding: Improve syslog message at device creation time bonding: Call netif_carrier_off after register_netdevice bonding: Incorrect TX queue offset net_sched: fix ip_tos2prio xfrm: fix __xfrm_route_forward() be2net: Fix UDP packet detected status in RX compl Phonet: fix aligned-mode pipe socket buffer header reserve netxen: support for GbE port settings ... Fix up conflicts in drivers/staging/brcm80211/brcmsmac/wl_mac80211.c with the staging updates.
| * Merge branch 'master' of ↵David S. Miller2011-03-15
| |\ | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
| | * af_unix: update locking commentDaniel Baluta2011-03-14
| | | | | | | | | | | | | | | | | | | | | We latch our state using a spinlock not a r/w kind of lock. Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | Merge branch 'master' of ↵David S. Miller2011-03-10
| |\| | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/bnx2x/bnx2x_cmn.c
| * | af_unix: remove unused struct sockaddr_un cruftHagen Paul Pfeifer2011-03-07
| | | | | | | | | | | | | | | Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: add __rcu annotations to sk_wq and wqEric Dumazet2011-02-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add proper RCU annotations/verbs to sk_wq and wq members Fix __sctp_write_space() sk_sleep() abuse (and sock->wq access) Fix sunrpc sk_sleep() abuse too Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | af_unix: coding style: remove one level of indentation in unix_shutdown()Alban Crequy2011-01-20
| | | | | | | | | | | | | | | | | | Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk> Reviewed-by: Ian Molton <ian.molton@collabora.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | af_unix: implement socket filterAlban Crequy2011-01-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linux Socket Filters can already be successfully attached and detached on unix sockets with setsockopt(sockfd, SOL_SOCKET, SO_{ATTACH,DETACH}_FILTER, ...). See: Documentation/networking/filter.txt But the filter was never used in the unix socket code so it did not work. This patch uses sk_filter() to filter buffers before delivery. This short program demonstrates the problem on SOCK_DGRAM. int main(void) { int i, j, ret; int sv[2]; struct pollfd fds[2]; char *message = "Hello world!"; char buffer[64]; struct sock_filter ins[32] = {{0,},}; struct sock_fprog filter; socketpair(AF_UNIX, SOCK_DGRAM, 0, sv); for (i = 0 ; i < 2 ; i++) { fds[i].fd = sv[i]; fds[i].events = POLLIN; fds[i].revents = 0; } for(j = 1 ; j < 13 ; j++) { /* Set a socket filter to truncate the message */ memset(ins, 0, sizeof(ins)); ins[0].code = BPF_RET|BPF_K; ins[0].k = j; filter.len = 1; filter.filter = ins; setsockopt(sv[1], SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)); /* send a message */ send(sv[0], message, strlen(message) + 1, 0); /* The filter should let the message pass but truncated. */ poll(fds, 2, 0); /* Receive the truncated message*/ ret = recv(sv[1], buffer, 64, 0); printf("received %d bytes, expected %d\n", ret, j); } for (i = 0 ; i < 2 ; i++) close(sv[i]); return 0; } Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk> Reviewed-by: Ian Molton <ian.molton@collabora.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge branch 'for-linus' of ↵Linus Torvalds2011-03-15
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (57 commits) tidy the trailing symlinks traversal up Turn resolution of trailing symlinks iterative everywhere simplify link_path_walk() tail Make trailing symlink resolution in path_lookupat() iterative update nd->inode in __do_follow_link() instead of after do_follow_link() pull handling of one pathname component into a helper fs: allow AT_EMPTY_PATH in linkat(), limit that to CAP_DAC_READ_SEARCH Allow passing O_PATH descriptors via SCM_RIGHTS datagrams readlinkat(), fchownat() and fstatat() with empty relative pathnames Allow O_PATH for symlinks New kind of open files - "location only". ext4: Copy fs UUID to superblock ext3: Copy fs UUID to superblock. vfs: Export file system uuid via /proc/<pid>/mountinfo unistd.h: Add new syscalls numbers to asm-generic x86: Add new syscalls for x86_64 x86: Add new syscalls for x86_32 fs: Remove i_nlink check from file system link callback fs: Don't allow to create hardlink for deleted file vfs: Add open by file handle support ...
| * | kill path_lookup()Al Viro2011-03-14
| |/ | | | | | | | | | | | | all remaining callers pass LOOKUP_PARENT to it, so flags argument can die; renamed to kern_path_parent() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* / net: fix multithreaded signal handling in unix recv routinesRainer Weikusat2011-03-07
|/ | | | | | | | | | | | | | | | | | | | | | | | The unix_dgram_recvmsg and unix_stream_recvmsg routines in net/af_unix.c utilize mutex_lock(&u->readlock) calls in order to serialize read operations of multiple threads on a single socket. This implies that, if all n threads of a process block in an AF_UNIX recv call trying to read data from the same socket, one of these threads will be sleeping in state TASK_INTERRUPTIBLE and all others in state TASK_UNINTERRUPTIBLE. Provided that a particular signal is supposed to be handled by a signal handler defined by the process and that none of this threads is blocking the signal, the complete_signal routine in kernel/signal.c will select the 'first' such thread it happens to encounter when deciding which thread to notify that a signal is supposed to be handled and if this is one of the TASK_UNINTERRUPTIBLE threads, the signal won't be handled until the one thread not blocking on the u->readlock mutex is woken up because some data to process has arrived (if this ever happens). The included patch fixes this by changing mutex_lock to mutex_lock_interruptible and handling possible error returns in the same way interruptions are handled by the actual receive-code. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: Avoid socket->sk NULL OOPS in stream connect security hooks.David S. Miller2011-01-05
| | | | | | | | | | | | | | | | unix_release() can asynchornously set socket->sk to NULL, and it does so without holding the unix_state_lock() on "other" during stream connects. However, the reverse mapping, sk->sk_socket, is only transitioned to NULL under the unix_state_lock(). Therefore make the security hooks follow the reverse mapping instead of the forward mapping. Reported-by: Jeremy Fitzhardinge <jeremy@goop.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'master' of ↵David S. Miller2010-12-08
|\ | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/wireless/ath/ath9k/ar9003_eeprom.c net/llc/af_llc.c
| * af_unix: limit recursion levelEric Dumazet2010-11-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Its easy to eat all kernel memory and trigger NMI watchdog, using an exploit program that queues unix sockets on top of others. lkml ref : http://lkml.org/lkml/2010/11/25/8 This mechanism is used in applications, one choice we have is to have a recursion limit. Other limits might be needed as well (if we queue other types of files), since the passfd mechanism is currently limited by socket receive queue sizes only. Add a recursion_level to unix socket, allowing up to 4 levels. Each time we send an unix socket through sendfd mechanism, we copy its recursion level (plus one) to receiver. This recursion level is cleared when socket receive queue is emptied. Reported-by: Марк Коренберг <socketpair@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | af_unix: optimize unix_dgram_poll()Eric Dumazet2010-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | unix_dgram_poll() is pretty expensive to check POLLOUT status, because it has to lock the socket to get its peer, take a reference on the peer to check its receive queue status, and queue another poll_wait on peer_wait. This all can be avoided if the process calling unix_dgram_poll() is not interested in POLLOUT status. It makes unix_dgram_recvmsg() faster by not queueing irrelevant pollers in peer_wait. On a test program provided by Alan Crequy : Before: real 0m0.211s user 0m0.000s sys 0m0.208s After: real 0m0.044s user 0m0.000s sys 0m0.040s Suggested-by: Davide Libenzi <davidel@xmailserver.org> Reported-by: Alban Crequy <alban.crequy@collabora.co.uk> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | af_unix: fix unix_dgram_poll() behavior for EPOLLOUT eventEric Dumazet2010-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alban Crequy reported a problem with connected dgram af_unix sockets and provided a test program. epoll() would miss to send an EPOLLOUT event when a thread unqueues a packet from the other peer, making its receive queue not full. This is because unix_dgram_poll() fails to call sock_poll_wait(file, &unix_sk(other)->peer_wait, wait); if the socket is not writeable at the time epoll_ctl(ADD) is called. We must call sock_poll_wait(), regardless of 'writable' status, so that epoll can be notified later of states changes. Misc: avoids testing twice (sk->sk_shutdown & RCV_SHUTDOWN) Reported-by: Alban Crequy <alban.crequy@collabora.co.uk> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | af_unix: use keyed wakeupsEric Dumazet2010-11-08
|/ | | | | | | | | | | | | | | | | | | | | | | | | | Instead of wakeup all sleepers, use wake_up_interruptible_sync_poll() to wakeup only ones interested into writing the socket. This patch is a specialization of commit 37e5540b3c9d (epoll keyed wakeups: make sockets use keyed wakeups). On a test program provided by Alan Crequy : Before: real 0m3.101s user 0m0.000s sys 0m6.104s After: real 0m0.211s user 0m0.000s sys 0m0.208s Reported-by: Alban Crequy <alban.crequy@collabora.co.uk> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* fs: allow for more than 2^31 filesEric Dumazet2010-10-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Robin Holt tried to boot a 16TB system and found af_unix was overflowing a 32bit value : <quote> We were seeing a failure which prevented boot. The kernel was incapable of creating either a named pipe or unix domain socket. This comes down to a common kernel function called unix_create1() which does: atomic_inc(&unix_nr_socks); if (atomic_read(&unix_nr_socks) > 2 * get_max_files()) goto out; The function get_max_files() is a simple return of files_stat.max_files. files_stat.max_files is a signed integer and is computed in fs/file_table.c's files_init(). n = (mempages * (PAGE_SIZE / 1024)) / 10; files_stat.max_files = n; In our case, mempages (total_ram_pages) is approx 3,758,096,384 (0xe0000000). That leaves max_files at approximately 1,503,238,553. This causes 2 * get_max_files() to integer overflow. </quote> Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long integers, and change af_unix to use an atomic_long_t instead of atomic_t. get_max_files() is changed to return an unsigned long. get_nr_files() is changed to return a long. unix_nr_socks is changed from atomic_t to atomic_long_t, while not strictly needed to address Robin problem. Before patch (on a 64bit kernel) : # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max -18446744071562067968 After patch: # echo 2147483648 >/proc/sys/fs/file-max # cat /proc/sys/fs/file-max 2147483648 # cat /proc/sys/fs/file-nr 704 0 2147483648 Reported-by: Robin Holt <holt@sgi.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: David Miller <davem@davemloft.net> Reviewed-by: Robin Holt <holt@sgi.com> Tested-by: Robin Holt <holt@sgi.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* AF_UNIX: Implement SO_TIMESTAMP and SO_TIMETAMPNS on Unix socketsAlban Crequy2010-10-05
| | | | | | | | | | | | | Userspace applications can already request to receive timestamps with: setsockopt(sockfd, SOL_SOCKET, SO_TIMESTAMP, ...) Although setsockopt() returns zero (success), timestamps are not added to the ancillary data. This patch fixes that on SOCK_DGRAM and SOCK_SEQPACKET Unix sockets. Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'master' of ↵David S. Miller2010-09-10
|\ | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/mac80211/main.c
| * UNIX: Do not loop forever at unix_autobind().Tetsuo Handa2010-09-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We assumed that unix_autobind() never fails if kzalloc() succeeded. But unix_autobind() allows only 1048576 names. If /proc/sys/fs/file-max is larger than 1048576 (e.g. systems with more than 10GB of RAM), a local user can consume all names using fork()/socket()/bind(). If all names are in use, those who call bind() with addr_len == sizeof(short) or connect()/sendmsg() with setsockopt(SO_PASSCRED) will continue while (1) yield(); loop at unix_autobind() till a name becomes available. This patch adds a loop counter in order to give up after 1048576 attempts. Calling yield() for once per 256 attempts may not be sufficient when many names are already in use, for __unix_find_socket_byname() can take long time under such circumstance. Therefore, this patch also adds cond_resched() call. Note that currently a local user can consume 2GB of kernel memory if the user is allowed to create and autobind 1048576 UNIX domain sockets. We should consider adding some restriction for autobind operation. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: poll() optimizationsEric Dumazet2010-09-06
|/ | | | | | | No need to test twice sk->sk_shutdown & RCV_SHUTDOWN Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* drop_monitor: convert some kfree_skb call sites to consume_skbNeil Horman2010-07-20
| | | | | | | | | | | | | | Convert a few calls from kfree_skb to consume_skb Noticed while I was working on dropwatch that I was detecting lots of internal skb drops in several places. While some are legitimate, several were not, freeing skbs that were at the end of their life, rather than being discarded due to an error. This patch converts those calls sites from using kfree_skb to consume_skb, which quiets the in-kernel drop_monitor code from detecting them as drops. Tested successfully by myself Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: Allow connecting to sockets in other network namespaces.Eric W. Biederman2010-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the restriction that only allows connecting to a unix domain socket identified by unix path that is in the same network namespace. Crossing network namespaces is always tricky and we did not support this at first, because of a strict policy of don't mix the namespaces. Later after Pavel proposed this we did not support this because no one had performed the audit to make certain using unix domain sockets across namespaces is safe. What fundamentally makes connecting to af_unix sockets in other namespaces is safe is that you have to have the proper permissions on the unix domain socket inode that lives in the filesystem. If you want strict isolation you just don't create inodes where unfriendlys can get at them, or with permissions that allow unfriendlys to open them. All nicely handled for us by the mount namespace and other standard file system facilities. I looked through unix domain sockets and they are a very controlled environment so none of the work that goes on in dev_forward_skb to make crossing namespaces safe appears needed, we are not loosing controll of the skb and so do not need to set up the skb to look like it is comming in fresh from the outside world. Further the fields in struct unix_skb_parms should not have any problems crossing network namespaces. Now that we handle SCM_CREDENTIALS in a way that gives useable values across namespaces. There does not appear to be any operational problems with encouraging the use of unix domain sockets across containers either. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: Allow credentials to work across user and pid namespaces.Eric W. Biederman2010-06-16
| | | | | | | | | | | In unix_skb_parms store pointers to struct pid and struct cred instead of raw uid, gid, and pid values, then translate the credentials on reception into values that are meaningful in the receiving processes namespaces. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* af_unix: Allow SO_PEERCRED to work across namespaces.Eric W. Biederman2010-06-16
| | | | | | | | | | | | | | | | Use struct pid and struct cred to store the peer credentials on struct sock. This gives enough information to convert the peer credential information to a value relative to whatever namespace the socket is in at the time. This removes nasty surprises when using SO_PEERCRED on socket connetions where the processes on either side are in different pid and user namespaces. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sock_def_readable() and friends RCU conversionEric Dumazet2010-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we need two atomic operations (and associated dirtying) per incoming packet. RCU conversion is pretty much needed : 1) Add a new structure, called "struct socket_wq" to hold all fields that will need rcu_read_lock() protection (currently: a wait_queue_head_t and a struct fasync_struct pointer). [Future patch will add a list anchor for wakeup coalescing] 2) Attach one of such structure to each "struct socket" created in sock_alloc_inode(). 3) Respect RCU grace period when freeing a "struct socket_wq" 4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct socket_wq" 5) Change sk_sleep() function to use new sk->sk_wq instead of sk->sk_sleep 6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside a rcu_read_lock() section. 7) Change all sk_has_sleeper() callers to : - Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock) - Use wq_has_sleeper() to eventually wakeup tasks. - Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock) 8) sock_wake_async() is modified to use rcu protection as well. 9) Exceptions : macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq" instead of dynamically allocated ones. They dont need rcu freeing. Some cleanups or followups are probably needed, (possible sk_callback_lock conversion to a spinlock for example...). Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sk_sleep() helperEric Dumazet2010-04-20
| | | | | | | | | | | | | | | | | Define a new function to return the waitqueue of a "struct sock". static inline wait_queue_head_t *sk_sleep(struct sock *sk) { return sk->sk_sleep; } Change all read occurrences of sk_sleep by a call to this function. Needed for a future RCU conversion. sk_sleep wont be a field directly available. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* AF_UNIX: update locking commentStephen Hemminger2010-02-18
| | | | | | | The lock used in unix_state_lock() is a spin_lock not reader-writer. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: spread __net_init, __net_exitAlexey Dobriyan2010-01-17
| | | | | | | | | | | __net_init/__net_exit are apparently not going away, so use them to full extent. In some cases __net_init was removed, because it was called from __net_exit code. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Move && and || to end of previous lineJoe Perches2009-11-29
| | | | | | | | | | | Not including net/atm/ Compiled tested x86 allyesconfig only Added a > 80 column line or two, which I ignored. Existing checkpatch plaints willfully, cheerfully ignored. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: netlink_getname, packet_getname -- use DECLARE_SOCKADDR guardCyrill Gorcunov2009-11-10
| | | | | | | | Use guard DECLARE_SOCKADDR in a few more places which allow us to catch if the structure copied back is too big. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: pass kern to net_proto_family create functionEric Paris2009-11-06
| | | | | | | | | | | The generic __sock_create function has a kern argument which allows the security system to make decisions based on if a socket is being created by the kernel or by userspace. This patch passes that flag to the net_proto_family specific create function, so it can do the same thing. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'master' of ↵David S. Miller2009-10-27
|\ | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/sh_eth.c
| * AF_UNIX: Fix deadlock on connecting to shutdown socketTomoki Sekiyama2009-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I found a deadlock bug in UNIX domain socket, which makes able to DoS attack against the local machine by non-root users. How to reproduce: 1. Make a listening AF_UNIX/SOCK_STREAM socket with an abstruct namespace(*), and shutdown(2) it. 2. Repeat connect(2)ing to the listening socket from the other sockets until the connection backlog is full-filled. 3. connect(2) takes the CPU forever. If every core is taken, the system hangs. PoC code: (Run as many times as cores on SMP machines.) int main(void) { int ret; int csd; int lsd; struct sockaddr_un sun; /* make an abstruct name address (*) */ memset(&sun, 0, sizeof(sun)); sun.sun_family = PF_UNIX; sprintf(&sun.sun_path[1], "%d", getpid()); /* create the listening socket and shutdown */ lsd = socket(AF_UNIX, SOCK_STREAM, 0); bind(lsd, (struct sockaddr *)&sun, sizeof(sun)); listen(lsd, 1); shutdown(lsd, SHUT_RDWR); /* connect loop */ alarm(15); /* forcely exit the loop after 15 sec */ for (;;) { csd = socket(AF_UNIX, SOCK_STREAM, 0); ret = connect(csd, (struct sockaddr *)&sun, sizeof(sun)); if (-1 == ret) { perror("connect()"); break; } puts("Connection OK"); } return 0; } (*) Make sun_path[0] = 0 to use the abstruct namespace. If a file-based socket is used, the system doesn't deadlock because of context switches in the file system layer. Why this happens: Error checks between unix_socket_connect() and unix_wait_for_peer() are inconsistent. The former calls the latter to wait until the backlog is processed. Despite the latter returns without doing anything when the socket is shutdown, the former doesn't check the shutdown state and just retries calling the latter forever. Patch: The patch below adds shutdown check into unix_socket_connect(), so connect(2) to the shutdown socket will return -ECONREFUSED. Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> Signed-off-by: Masanori Yoshida <masanori.yoshida.tv@hitachi.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: mark net_proto_ops as constStephen Hemminger2009-10-07
|/ | | | | | | All usages of structure net_proto_ops should be declared const. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: unix: fix sending fds in multiple buffersMiklos Szeredi2009-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kalle Olavi Niemitalo reported that: "..., when one process calls sendmsg once to send 43804 bytes of data and one file descriptor, and another process then calls recvmsg three times to receive the 16032+16032+11740 bytes, each of those recvmsg calls returns the file descriptor in the ancillary data. I confirmed this with strace. The behaviour differs from Linux 2.6.26, where reportedly only one of those recvmsg calls (I think the first one) returned the file descriptor." This bug was introduced by a patch from me titled "net: unix: fix inflight counting bug in garbage collector", commit 6209344f5. And the reason is, quoting Kalle: "Before your patch, unix_attach_fds() would set scm->fp = NULL, so that if the loop in unix_stream_sendmsg() ran multiple iterations, it could not call unix_attach_fds() again. But now, unix_attach_fds() leaves scm->fp unchanged, and I think this causes it to be called multiple times and duplicate the same file descriptors to each struct sk_buff." Fix this by introducing a flag that is cleared at the start and set when the fds attached to the first buffer. The resulting code should work equivalently to the one on 2.6.26. Reported-by: Kalle Olavi Niemitalo <kon@iki.fi> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: adding memory barrier to the poll and receive callbacksJiri Olsa2009-07-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding memory barrier after the poll_wait function, paired with receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper to wrap the memory barrier. Without the memory barrier, following race can happen. The race fires, when following code paths meet, and the tp->rcv_nxt and __add_wait_queue updates stay in CPU caches. CPU1 CPU2 sys_select receive packet ... ... __add_wait_queue update tp->rcv_nxt ... ... tp->rcv_nxt check sock_def_readable ... { schedule ... if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep) ... } If there was no cache the code would work ok, since the wait_queue and rcv_nxt are opposit to each other. Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already passed the tp->rcv_nxt check and sleeps, or will get the new value for tp->rcv_nxt and will return with new data mask. In both cases the process (CPU1) is being added to the wait queue, so the waitqueue_active (CPU2) call cannot miss and will wake up CPU1. The bad case is when the __add_wait_queue changes done by CPU1 stay in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then endup calling schedule and sleep forever if there are no more data on the socket. Calls to poll_wait in following modules were ommited: net/bluetooth/af_bluetooth.c net/irda/af_irda.c net/irda/irnet/irnet_ppp.c net/mac80211/rc80211_pid_debugfs.c net/phonet/socket.c net/rds/af_rds.c net/rfkill/core.c net/sunrpc/cache.c net/sunrpc/rpc_pipe.c net/tipc/socket.c Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: correct off-by-one write allocations reportsEric Dumazet2009-06-18
| | | | | | | | | | | | | commit 2b85a34e911bf483c27cfdd124aeb1605145dc80 (net: No more expensive sock_hold()/sock_put() on each tx) changed initial sk_wmem_alloc value. We need to take into account this offset when reporting sk_wmem_alloc to user, in PROC_FS files or various ioctls (SIOCOUTQ/TIOCOUTQ) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* New helper - current_umask()Al Viro2009-03-31
| | | | | | | current->fs->umask is what most of fs_struct users are doing. Put that into a helper function. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* unix: remove some pointless conditionals before kfree_skb()Wei Yongjun2009-02-27
| | | | | | | Remove some pointless conditionals before kfree_skb(). Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* introduce new LSM hooks where vfsmount is available.Kentaro Takeda2008-12-31
| | | | | | | | | | Add new LSM hooks for path-based checks. Call them on directory-modifying operations at the points where we still know the vfsmount involved. Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds2008-12-28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1429 commits) net: Allow dependancies of FDDI & Tokenring to be modular. igb: Fix build warning when DCA is disabled. net: Fix warning fallout from recent NAPI interface changes. gro: Fix potential use after free sfc: If AN is enabled, always read speed/duplex from the AN advertising bits sfc: When disabling the NIC, close the device rather than unregistering it sfc: SFT9001: Add cable diagnostics sfc: Add support for multiple PHY self-tests sfc: Merge top-level functions for self-tests sfc: Clean up PHY mode management in loopback self-test sfc: Fix unreliable link detection in some loopback modes sfc: Generate unique names for per-NIC workqueues 802.3ad: use standard ethhdr instead of ad_header 802.3ad: generalize out mac address initializer 802.3ad: initialize ports LACPDU from const initializer 802.3ad: remove typedef around ad_system 802.3ad: turn ports is_individual into a bool 802.3ad: turn ports is_enabled into a bool 802.3ad: make ntt bool ixgbe: Fix set_ringparam in ixgbe to use the same memory pools. ... Fixed trivial IPv4/6 address printing conflicts in fs/cifs/connect.c due to the conversion to %pI (in this networking merge) and the addition of doing IPv6 addresses (from the earlier merge of CIFS).
| * Merge branch 'master' of ↵David S. Miller2008-12-02
| |\ | | | | | | | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/ixgbe/ixgbe_main.c drivers/net/smc91x.c
| * | net: Use a percpu_counter for sockets_allocatedEric Dumazet2008-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of using one atomic_t per protocol, use a percpu_counter for "sockets_allocated", to reduce cache line contention on heavy duty network servers. Note : We revert commit (248969ae31e1b3276fc4399d67ce29a5d81e6fd9 net: af_unix can make unix_nr_socks visbile in /proc), since it is not anymore used after sock_prot_inuse_add() addition Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: Make sure BHs are disabled in sock_prot_inuse_add()Eric Dumazet2008-11-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The rule of calling sock_prot_inuse_add() is that BHs must be disabled. Some new calls were added where this was not true and this tiggers warnings as reported by Ilpo. Fix this by adding explicit BH disabling around those call sites, or moving sock_prot_inuse_add() call inside an existing BH disabled section. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: Make sure BHs are disabled in sock_prot_inuse_add()David S. Miller2008-11-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The rule of calling sock_prot_inuse_add() is that BHs must be disabled. Some new calls were added where this was not true and this tiggers warnings as reported by Ilpo. Fix this by adding explicit BH disabling around those call sites. Signed-off-by: David S. Miller <davem@davemloft.net>