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* Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linuxLinus Torvalds2012-05-281-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull writeback tree from Wu Fengguang: "Mainly from Jan Kara to avoid iput() in the flusher threads." * tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Avoid iput() from flusher thread vfs: Rename end_writeback() to clear_inode() vfs: Move waiting for inode writeback from end_writeback() to evict_inode() writeback: Refactor writeback_single_inode() writeback: Remove wb->list_lock from writeback_single_inode() writeback: Separate inode requeueing after writeback writeback: Move I_DIRTY_PAGES handling writeback: Move requeueing when I_SYNC set to writeback_sb_inodes() writeback: Move clearing of I_SYNC into inode_sync_complete() writeback: initialize global_dirty_limit fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds mm: page-writeback.c: local functions should not be exposed globally
| * vfs: Rename end_writeback() to clear_inode()Jan Kara2012-05-061-1/+1
| | | | | | | | | | | | | | | | | | After we moved inode_sync_wait() from end_writeback() it doesn't make sense to call the function end_writeback() anymore. Rename it to clear_inode() which well says what the function really does - set I_CLEAR flag. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
* | userns: Replace user_ns_map_uid and user_ns_map_gid with from_kuid and from_kgidEric W. Biederman2012-05-031-2/+1
| | | | | | | | | | | | | | These function are no longer needed replace them with their more useful equivalents. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | mqueue: Explicitly capture the user namespace to send the notification to.Eric W. Biederman2012-04-071-1/+8
| | | | | | | | | | | | | | | | Stop relying on user->user_ns which is going away and instead capture the user_namespace of the process we are supposed to notify. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | userns: Use cred->user_ns instead of cred->user->user_nsEric W. Biederman2012-04-071-1/+1
|/ | | | | | | | | Optimize performance and prepare for the removal of the user_ns reference from user_struct. Remove the slow long walk through cred->user->user_ns and instead go straight to cred->user_ns. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds2012-03-291-6/+64
|\ | | | | | | | | | | | | | | | | Pull arch/tile (really asm-generic) update from Chris Metcalf: "These are a couple of asm-generic changes that apply to tile." * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: compat: use sys_sendfile64() implementation for sendfile syscall [PATCH v3] ipc: provide generic compat versions of IPC syscalls
| * [PATCH v3] ipc: provide generic compat versions of IPC syscallsChris Metcalf2012-03-151-6/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When using the "compat" APIs, architectures will generally want to be able to make direct syscalls to msgsnd(), shmctl(), etc., and in the kernel we would want them to be handled directly by compat_sys_xxx() functions, as is true for other compat syscalls. However, for historical reasons, several of the existing compat IPC syscalls do not do this. semctl() expects a pointer to the fourth argument, instead of the fourth argument itself. msgsnd(), msgrcv() and shmat() expect arguments in different order. This change adds an ARCH_WANT_OLD_COMPAT_IPC config option that can be set to preserve this behavior for ports that use it (x86, sparc, powerpc, s390, and mips). No actual semantics are changed for those architectures, and there is only a minimal amount of code refactoring in ipc/compat.c. Newer architectures like tile (and perhaps future architectures such as arm64 and unicore64) should not select this option, and thus can avoid having any IPC-specific code at all in their architecture-specific compat layer. In the same vein, if this option is not selected, IPC_64 mode is assumed, since that's what the <asm-generic> headers expect. The workaround code in "tile" for msgsnd() and msgrcv() is removed with this change; it also fixes the bug that shmat() and semctl() were not being properly handled. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
* | Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds2012-03-221-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge first batch of patches from Andrew Morton: "A few misc things and all the MM queue" * emailed from Andrew Morton <akpm@linux-foundation.org>: (92 commits) memcg: avoid THP split in task migration thp: add HPAGE_PMD_* definitions for !CONFIG_TRANSPARENT_HUGEPAGE memcg: clean up existing move charge code mm/memcontrol.c: remove unnecessary 'break' in mem_cgroup_read() mm/memcontrol.c: remove redundant BUG_ON() in mem_cgroup_usage_unregister_event() mm/memcontrol.c: s/stealed/stolen/ memcg: fix performance of mem_cgroup_begin_update_page_stat() memcg: remove PCG_FILE_MAPPED memcg: use new logic for page stat accounting memcg: remove PCG_MOVE_LOCK flag from page_cgroup memcg: simplify move_account() check memcg: remove EXPORT_SYMBOL(mem_cgroup_update_page_stat) memcg: kill dead prev_priority stubs memcg: remove PCG_CACHE page_cgroup flag memcg: let css_get_next() rely upon rcu_read_lock() cgroup: revert ss_id_lock to spinlock idr: make idr_get_next() good for rcu_read_lock() memcg: remove unnecessary thp check in page stat accounting memcg: remove redundant returns memcg: enum lru_list lru ...
| * | hugetlbfs: fix alignment of huge page requestsSteven Truelove2012-03-211-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When calling shmget() with SHM_HUGETLB, shmget aligns the request size to PAGE_SIZE, but this is not sufficient. Modify hugetlb_file_setup() to align requests to the huge page size, and to accept an address argument so that all alignment checks can be performed in hugetlb_file_setup(), rather than in its callers. Change newseg() and mmap_pgoff() to match the new prototype and eliminate a now redundant alignment check. [akpm@linux-foundation.org: fix build] Signed-off-by: Steven Truelove <steven.truelove@utoronto.ca> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2012-03-211-17/+7
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "This is _not_ all; in particular, Miklos' and Jan's stuff is not there yet." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits) ext4: initialization of ext4_li_mtx needs to be done earlier debugfs-related mode_t whack-a-mole hfsplus: add an ioctl to bless files hfsplus: change finder_info to u32 hfsplus: initialise userflags qnx4: new helper - try_extent() qnx4: get rid of qnx4_bread/qnx4_getblk take removal of PF_FORKNOEXEC to flush_old_exec() trim includes in inode.c um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it um: embed ->stub_pages[] into mmu_context gadgetfs: list_for_each_safe() misuse ocfs2: fix leaks on failure exits in module_init ecryptfs: make register_filesystem() the last potential failure exit ntfs: forgets to unregister sysctls on register_filesystem() failure logfs: missing cleanup on register_filesystem() failure jfs: mising cleanup on register_filesystem() failure make configfs_pin_fs() return root dentry on success configfs: configfs_create_dir() has parent dentry in dentry->d_parent configfs: sanitize configfs_create() ...
| * | switch open-coded instances of d_make_root() to new helperAl Viro2012-03-201-17/+7
| |/ | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* / security: trim security.hAl Viro2012-02-141-0/+2
|/ | | | | | | Trim security.h Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Morris <jmorris@namei.org>
* SHM_UNLOCK: fix Unevictable pages stranded after swapHugh Dickins2012-01-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit cc39c6a9bbde ("mm: account skipped entries to avoid looping in find_get_pages") correctly fixed an infinite loop; but left a problem that find_get_pages() on shmem would return 0 (appearing to callers to mean end of tree) when it meets a run of nr_pages swap entries. The only uses of find_get_pages() on shmem are via pagevec_lookup(), called from invalidate_mapping_pages(), and from shmctl SHM_UNLOCK's scan_mapping_unevictable_pages(). The first is already commented, and not worth worrying about; but the second can leave pages on the Unevictable list after an unusual sequence of swapping and locking. Fix that by using shmem_find_get_pages_and_swap() (then ignoring the swap) instead of pagevec_lookup(). But I don't want to contaminate vmscan.c with shmem internals, nor shmem.c with LRU locking. So move scan_mapping_unevictable_pages() into shmem.c, renaming it shmem_unlock_mapping(); and rename check_move_unevictable_page() to check_move_unevictable_pages(), looping down an array of pages, oftentimes under the same lock. Leave out the "rotate unevictable list" block: that's a leftover from when this was used for /proc/sys/vm/scan_unevictable_pages, whose flawed handling involved looking at pages at tail of LRU. Was there significance to the sequence first ClearPageUnevictable, then test page_evictable, then SetPageUnevictable here? I think not, we're under LRU lock, and have no barriers between those. Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shaohua.li@intel.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michel Lespinasse <walken@google.com> Cc: <stable@vger.kernel.org> [back to 3.1 but will need respins] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SHM_UNLOCK: fix long unpreemptible sectionHugh Dickins2012-01-231-15/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | scan_mapping_unevictable_pages() is used to make SysV SHM_LOCKed pages evictable again once the shared memory is unlocked. It does this with pagevec_lookup()s across the whole object (which might occupy most of memory), and takes 300ms to unlock 7GB here. A cond_resched() every PAGEVEC_SIZE pages would be good. However, KOSAKI-san points out that this is called under shmem.c's info->lock, and it's also under shm.c's shm_lock(), both spinlocks. There is no strong reason for that: we need to take these pages off the unevictable list soonish, but those locks are not required for it. So move the call to scan_mapping_unevictable_pages() from shmem.c's unlock handling up to shm.c's unlock handling. Remove the recently added barrier, not needed now we have spin_unlock() before the scan. Use get_file(), with subsequent fput(), to make sure we have a reference to mapping throughout scan_mapping_unevictable_pages(): that's something that was previously guaranteed by the shm_lock(). Remove shmctl's lru_add_drain_all(): we don't fault in pages at SHM_LOCK time, and we lazily discover them to be Unevictable later, so it serves no purpose for SHM_LOCK; and serves no purpose for SHM_UNLOCK, since pages still on pagevec are not marked Unevictable. The original code avoided redundant rescans by checking VM_LOCKED flag at its level: now avoid them by checking shp's SHM_LOCKED. The original code called scan_mapping_unevictable_pages() on a locked area at shm_destroy() time: perhaps we once had accounting cross-checks which required that, but not now, so skip the overhead and just let inode eviction deal with them. Put check_move_unevictable_page() and scan_mapping_unevictable_pages() under CONFIG_SHMEM (with stub for the TINY case when ramfs is used), more as comment than to save space; comment them used for SHM_UNLOCK. Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shaohua.li@intel.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/mqueue: simplify reading msgqueue limitDavidlohr Bueso2012-01-231-2/+1
| | | | | | | | | | Because the current task is being used to get the limit, we can simply use rlimit() instead of task_rlimit(). Signed-off-by: Davidlohr Bueso <dave@gnu.org> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* user namespace: make signal.c respect user namespacesSerge E. Hallyn2012-01-101-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ipc/mqueue.c: for __SI_MESQ, convert the uid being sent to recipient's user namespace. (new, thanks Oleg) __send_signal: convert current's uid to the recipient's user namespace for any siginfo which is not SI_FROMKERNEL (patch from Oleg, thanks again :) do_notify_parent and do_notify_parent_cldstop: map task's uid to parent's user namespace ptrace_signal maps parent's uid into current's user namespace before including in signal to current. IIUC Oleg has argued that this shouldn't matter as the debugger will play with it, but it seems like not converting the value currently being set is misleading. Changelog: Sep 20: Inspired by Oleg's suggestion, define map_cred_ns() helper to simplify callers and help make clear what we are translating (which uid into which namespace). Passing the target task would make callers even easier to read, but we pass in user_ns because current_user_ns() != task_cred_xxx(current, user_ns). Sep 20: As recommended by Oleg, also put task_pid_vnr() under rcu_read_lock in ptrace_signal(). Sep 23: In send_signal(), detect when (user) signal is coming from an ancestor or unrelated user namespace. Pass that on to __send_signal, which sets si_uid to 0 or overflowuid if needed. Oct 12: Base on Oleg's fixup_uid() patch. On top of that, handle all SI_FROMKERNEL cases at callers, because we can't assume sender is current in those cases. Nov 10: (mhelsley) rename fixup_uid to more meaningful usern_fixup_signal_uid Nov 10: (akpm) make the !CONFIG_USER_NS case clearer Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> From: Serge Hallyn <serge.hallyn@canonical.com> Subject: __send_signal: pass q->info, not info, to userns_fixup_signal_uid (v2) Eric Biederman pointed out that passing info is a bug and could lead to a NULL pointer deref to boot. A collection of signal, securebits, filecaps, cap_bounds, and a few other ltp tests passed with this kernel. Changelog: Nov 18: previous patch missed a leading '&' Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> From: Dan Carpenter <dan.carpenter@oracle.com> Subject: ipc/mqueue: lock() => unlock() typo There was a double lock typo introduced in b085f4bd6b21 "user namespace: make signal.c respect user namespaces" Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* switch mq_open() to umode_tAl Viro2012-01-031-1/+1
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* mqueue: propagate umode_tAl Viro2012-01-031-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch ->create() to umode_tAl Viro2012-01-031-2/+2
| | | | | | | | vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: fix the stupidity with i_dentry in inode destructorsAl Viro2012-01-031-1/+0
| | | | | | | | | | Seeing that just about every destructor got that INIT_LIST_HEAD() copied into it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once(); the cost of taking it into inode_init_always() will be negligible for pipes and sockets and negative for everything else. Not to mention the removal of boilerplate code from ->destroy_inode() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ... and the same kind of leak for mqueueAl Viro2011-12-092-10/+3
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ipc/sem.c: remove private structures from public header fileManfred Spraul2011-11-021-0/+46
| | | | | | | | | | | | | | | | | | include/linux/sem.h contains several structures that are only used within ipc/sem.c. The patch moves them into ipc/sem.c - there is no need to expose the structures to the whole kernel. No functional changes, only whitespace cleanups and 80-char per line fixes. Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Galbraith <efault@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/sem.c: handle spurious wakeupsManfred Spraul2011-11-021-0/+9
| | | | | | | | | | | | | | semtimedop() does not handle spurious wakeups, it returns -EINTR to user space. Most other schedule() users would just loop and not return to user space. The patch adds such a loop to semtimedop() Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Galbraith <efault@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/sem.c: fix return code race with semop vs. semop +semctl(IPC_RMID)Manfred Spraul2011-11-021-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sys_semtimedop() may return -EIDRM although the semaphore operation completed successfully: thread 1: thread 2: semtimedop(), sleeps semop(): * acquires sem_lock() semtimedop() woken up due to timeout sem_lock() loops * notices that thread 2 could be completed. * performs the operations that thread 2 is sleeping on. * marks the semaphore operation as IN_WAKEUP * drops sem_lock(), does wakeup, sets return code to 0 * thread delayed due to interrupt, whatever * returns to user space * thread still delayed semctl(IPC_RMID) * acquires sem_lock() * ipc_rmid(), ipcp->deleted=1 * drops sem_lock() * thread finally continues - but seem_lock() now fails due to ipcp->deleted == 1 * returns -EIDRM instead of 0 The fix is trivial: Always use the return code in queue.status. In real world, the race probably doesn't matter: If the semaphore array is destroyed, the app is probably not interested if the last operation succeeded or was already cancelled. Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Galbraith <efault@gmx.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/mqueue.c: fix wrong use of schedule_hrtimeout_range_clock()Wanlong Gao2011-10-311-2/+2
| | | | | | | | | | | | | Fix the wrong use of schedule_hrtimeout_range_clock() in wq_sleep(), although it is harmless for the syscall mq_timed* now. It was introduced by 9ca7d8e ("mqueue: Convert message queue timeout to use hrtimers"). Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Cc: Carsten Emde <C.Emde@osadl.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Do 'shm_init_ns()' in an early pure_initcallLinus Torvalds2011-08-041-1/+8
| | | | | | | | | | | | | | | This isn't really critical any more, since other patches (commit 298507d4d2cf: "shm: optimize exit_shm()") have caused us to not actually need to touch the rw_mutex unless there are actual shm segments associated with the namespace, but we really should do tne shm_init_ns() earlier than we do now. This, together with commit 288d5abec831 ("Boot up with usermodehelper disabled") will mean that we really do initialize the initial ipc namespace data structure before we run any tasks. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* shm: optimize exit_shm()Vasiliy Kulikov2011-08-031-0/+3
| | | | | | | | | | | | | We may optimistically check .in_use == 0 without holding the rw_mutex: it's the common case, and if it's zero, there certainly won't be any segments associated with us. After taking the lock, the idr_for_each() will do the right thing, so we could now drop the re-check inside the lock without any real cost. But it won't hurt. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* shm: fix wrong testsVasiliy Kulikov2011-08-031-2/+2
| | | | | | | | | Commit 4c677e2eefdb ("shm: optimize locking and ipc_namespace getting") introduced a copy-paste bug. Due to the bug cycle optimizations were disabled. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* shm: optimize locking and ipc_namespace gettingVasiliy Kulikov2011-07-301-33/+28
| | | | | | | | | | | | | | | | | | shm_lock() does a lookup of shm segment in shm_ids(ns).ipcs_idr, which is redundant as we already know shmid_kernel address. An actual lock is also not required for reads until we really want to destroy the segment. exit_shm() and shm_destroy_orphaned() may avoid the loop by checking whether there is at least one segment in current ipc_namespace. The check of nsproxy and ipc_ns against NULL is redundant as exit_shm() is called from do_exit() before the call to exit_notify(), so the dereferencing current->nsproxy->ipc_ns is guaranteed to be safe. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* shm: handle separate PID namespaces caseVasiliy Kulikov2011-07-301-7/+20
| | | | | | | | | | | | | | | | | shm_try_destroy_orphaned() and shm_try_destroy_current() didn't handle the case of separate PID namespaces, but a single IPC namespace. If there are tasks with the same PID values using the same shmem object, the wrong destroy decision could be reached. On shm segment creation store the pointer to the creator task in shmid_kernel->shm_creator field and zero it on task exit. Then use the ->shm_creator insread of shm_cprid in both functions. As shmid_kernel object is already locked at this stage, no additional locking is needed. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc: introduce shm_rmid_forced sysctlVasiliy Kulikov2011-07-262-4/+129
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for the shm_rmid_forced sysctl. If set to 1, all shared memory objects in current ipc namespace will be automatically forced to use IPC_RMID. The POSIX way of handling shmem allows one to create shm objects and call shmdt(), leaving shm object associated with no process, thus consuming memory not counted via rlimits. With shm_rmid_forced=1 the shared memory object is counted at least for one process, so OOM killer may effectively kill the fat process holding the shared memory. It obviously breaks POSIX - some programs relying on the feature would stop working. So set shm_rmid_forced=1 only if you're sure nobody uses "orphaned" memory. Use shm_rmid_forced=0 by default for compatability reasons. The feature was previously impemented in -ow as a configure option. [akpm@linux-foundation.org: fix documentation, per Randy] [akpm@linux-foundation.org: fix warning] [akpm@linux-foundation.org: readability/conventionality tweaks] [akpm@linux-foundation.org: fix shm_rmid_forced/shm_forced_rmid confusion, use standard comment layout] Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Serge E. Hallyn" <serge.hallyn@canonical.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Solar Designer <solar@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/mqueue.c: fix mq_open() return valueJiri Slaby2011-07-261-5/+7
| | | | | | | | | | | | | | | | | | | | | | We return ENOMEM from mqueue_get_inode even when we have enough memory. Namely in case the system rlimit of mqueue was reached. This error propagates to mq_queue and user sees the error unexpectedly. So fix this up to properly return EMFILE as described in the manpage: EMFILE The process already has the maximum number of files and message queues open. instead of: ENOMEM Insufficient memory. With the previous patch we just switch to ERR_PTR/PTR_ERR/IS_ERR error handling here. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/mqueue.c: refactor failure handlingJiri Slaby2011-07-261-56/+57
| | | | | | | | | | | | | | | If new_inode fails to allocate an inode we need only to return with NULL. But now we test the opposite and have all the work in a nested block. So do the opposite to save one indentation level (and remove unnecessary line breaks). This is only a preparation/cleanup for the next patch where we fix up return values from mqueue_get_inode. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/sem.c: fix race with concurrent semtimedop() timeouts and IPC_RMIDManfred Spraul2011-07-251-2/+11
| | | | | | | | | | | | | | | | | | | | If a semaphore array is removed and in parallel a sleeping task is woken up (signal or timeout, does not matter), then the woken up task does not wait until wake_up_sem_queue_do() is completed. This will cause crashes, because wake_up_sem_queue_do() will read from a stale pointer. The fix is simple: Regardless of anything, always call get_queue_result(). This function waits until wake_up_sem_queue_do() has finished it's task. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=27142 Reported-by: Yuriy Yevtukhov <yuriy@ucoz.com> Reported-by: Harald Laabs <kernel@dasr.de> Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: <stable@kernel.org> [2.6.35+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-07-221-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: (107 commits) vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filp isofs: Remove global fs lock jffs2: fix IN_DELETE_SELF on overwriting rename() killing a directory fix IN_DELETE_SELF on overwriting rename() on ramfs et.al. mm/truncate.c: fix build for CONFIG_BLOCK not enabled fs:update the NOTE of the file_operations structure Remove dead code in dget_parent() AFS: Fix silly characters in a comment switch d_add_ci() to d_splice_alias() in "found negative" case as well simplify gfs2_lookup() jfs_lookup(): don't bother with . or .. get rid of useless dget_parent() in btrfs rename() and link() get rid of useless dget_parent() in fs/btrfs/ioctl.c fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers drivers: fix up various ->llseek() implementations fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek Ext4: handle SEEK_HOLE/SEEK_DATA generically Btrfs: implement our own ->llseek fs: add SEEK_HOLE and SEEK_DATA flags reiserfs: make reiserfs default to barrier=flush ... Fix up trivial conflicts in fs/xfs/linux-2.6/xfs_super.c due to the new shrinker callout for the inode cache, that clashed with the xfs code to start the periodic workers later.
| * fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlersJosef Bacik2011-07-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | ipc,rcu: Convert call_rcu(ipc_immediate_free) to kfree_rcu()Lai Jiangshan2011-07-201-15/+1
| | | | | | | | | | | | | | | | | | | | The rcu callback ipc_immediate_free() just calls a kfree(), so we use kfree_rcu() instead of the call_rcu(ipc_immediate_free). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
* | ipc,rcu: Convert call_rcu(free_un) to kfree_rcu()Lai Jiangshan2011-07-201-8/+2
|/ | | | | | | | | | | The rcu callback free_un() just calls a kfree(), so we use kfree_rcu() instead of the call_rcu(free_un). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Manfred Spraul <manfred@colorfullife.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
* mm: don't access vm_flags as 'int'KOSAKI Motohiro2011-05-261-1/+1
| | | | | | | | | | | The type of vma->vm_flags is 'unsigned long'. Neither 'int' nor 'unsigned int'. This patch fixes such misuse. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> [ Changed to use a typedef - we'll extend it to cover more cases later, since there has been discussion about making it a 64-bit type.. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ns proc: Add support for the ipc namespaceEric W. Biederman2011-05-101-0/+37
| | | | | Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* Fix common misspellingsLucas De Marchi2011-03-313-4/+4
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* ipc: fix util.c kernel-doc warningsRandy Dunlap2011-03-271-1/+3
| | | | | | | | | | | | Fix ipc/util.c kernel-doc warnings: Warning(ipc/util.c:336): No description found for parameter 'ns' Warning(ipc/util.c:620): No description found for parameter 'ns' Warning(ipc/util.c:790): No description found for parameter 'ns' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Reviewed-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipcns: fix use after free in free_ipc_ns()Xiaotian Feng2011-03-251-1/+1
| | | | | | | | | | | | | | commit b515498 ("userns: add a user namespace owner of ipc ns") added a user namespace owner of ipc ns, but it also introduced a use after free in free_ipc_ns(). Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Acked-by: "Serge E. Hallyn" <serge.hallyn@canonical.com> Acked-by: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* userns: user namespaces: convert several capable() callsSerge E. Hallyn2011-03-236-29/+42
| | | | | | | | | | | | | | | | | | | | | | | | | CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(), because the resource comes from current's own ipc namespace. setuid/setgid are to uids in own namespace, so again checks can be against current_user_ns(). Changelog: Jan 11: Use task_ns_capable() in place of sched_capable(). Jan 11: Use nsown_capable() as suggested by Bastian Blank. Jan 11: Clarify (hopefully) some logic in futex and sched.c Feb 15: use ns_capable for ipc, not nsown_capable Feb 23: let copy_ipcs handle setting ipc_ns->user_ns Feb 23: pass ns down rather than taking it from current [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* userns: add a user namespace owner of ipc nsSerge E. Hallyn2011-03-232-2/+8
| | | | | | | | | | | | | | | | Changelog: Feb 15: Don't set new ipc->user_ns if we didn't create a new ipc_ns. Feb 23: Move extern declaration to ipc_namespace.h, and group fwd declarations at top. Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs: icache RCU free inodesNick Piggin2011-01-071-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* ipc: shm: fix information leak to userlandVasiliy Kulikov2010-10-301-0/+1
| | | | | | | | | | | The shmid_ds structure is copied to userland with shm_unused{,2,3} fields unitialized. It leads to leaking of contents of kernel stack memory. Signed-off-by: Vasiliy Kulikov <segooon@gmail.com> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* switch get_sb_ns() usersAl Viro2010-10-291-4/+4
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ipc: initialize structure memory to zero for compat functionsDan Rosenberg2010-10-272-0/+11
| | | | | | | | | | | | This takes care of leaking uninitialized kernel stack memory to userspace from non-zeroed fields in structs in compat ipc functions. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ipc/shm.c: add RSS and swap size information to /proc/sysvipc/shmHelge Deller2010-10-271-21/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel currently provides no functionality to analyze the RSS and swap space usage of each individual sysvipc shared memory segment. This patch adds this info for each existing shm segment by extending the output of /proc/sysvipc/shm by two columns for RSS and swap. Since shmctl(SHM_INFO) already provides a similiar calculation (it currently sums up all RSS/swap info for all segments), I did split out a static function which is now used by the /proc/sysvipc/shm output and shmctl(SHM_INFO). SAP products (esp. the SAP Netweaver ABAP Kernel) uses lots of big shared memory segments (we often have Linux systems with >= 16GB shm usage). Sometimes we get customer reports about "slow" system responses and while looking into their configurations we often find massive swapping activity on the system. With this patch it's now easy to see from the command line if and which shm segments gets swapped out (and how much) and can more easily give recommendations for system tuning. Without the patch it's currently not possible to do such shm analysis at all. Also... Add some spaces in front of the "size" field for 64bit kernels to get the columns correct if you cat the contents of the file. In sysvipc_shm_proc_show() the kernel prints the size value in "SPEC_SIZE" format, which is defined like this: #if BITS_PER_LONG <= 32 #define SIZE_SPEC "%10lu" #else #define SIZE_SPEC "%21lu" #endif So, if the header is not adjusted, the columns are not correctly aligned. I actually tested this on 32- and 64-bit and it seems correct now. Signed-off-by: Helge Deller <deller@gmx.de> Cc: Manfred Spraul <manfred@colorfullife.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>