user/sven/linux.git/kernel, branch v3.8.2

cgroup: fix exit() vs rmdir() race

2013-03-03T22:03:38Z

commit 71b5707e119653039e6e95213f00479668c79b75 upstream. In cgroup_exit() put_css_set_taskexit() is called without any lock, which might lead to accessing a freed cgroup: thread1 thread2 --------------------------------------------- exit() cgroup_exit() put_css_set_taskexit() atomic_dec(cgrp->count); rmdir(); /* not safe !! */ check_for_release(cgrp); rcu_read_lock() can be used to make sure the cgroup is alive. Signed-off-by: Li Zefan Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

cpuset: fix cpuset_print_task_mems_allowed() vs rename() race

2013-03-03T22:03:38Z

commit 63f43f55c9bbc14f76b582644019b8a07dc8219a upstream. rename() will change dentry->d_name. The result of this race can be worse than seeing partially rewritten name, but we might access a stale pointer because rename() will re-allocate memory to hold a longer name. It's safe in the protection of dentry->d_lock. v2: check NULL dentry before acquiring dentry lock. Signed-off-by: Li Zefan Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

workqueue: consider work function when searching for busy work items

2013-03-03T22:03:38Z

commit a2c1c57be8d9fd5b716113c8991d3d702eeacf77 upstream. To avoid executing the same work item concurrenlty, workqueue hashes currently busy workers according to their current work items and looks up the the table when it wants to execute a new work item. If there already is a worker which is executing the new work item, the new item is queued to the found worker so that it gets executed only after the current execution finishes. Unfortunately, a work item may be freed while being executed and thus recycled for different purposes. If it gets recycled for a different work item and queued while the previous execution is still in progress, workqueue may make the new work item wait for the old one although the two aren't really related in any way. In extreme cases, this false dependency may lead to deadlock although it's extremely unlikely given that there aren't too many self-freeing work item users and they usually don't wait for other work items. To alleviate the problem, record the current work function in each busy worker and match it together with the work item address in find_worker_executing_work(). While this isn't complete, it ensures that unrelated work items don't interact with each other and in the very unlikely case where a twisted wq user triggers it, it's always onto itself making the culprit easy to spot. Signed-off-by: Tejun Heo Reported-by: Andrey Isakov Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=51701 Cc: stable@vger.kernel.org

sysctl: fix null checking in bin_dn_node_address()

2013-03-03T22:03:36Z

commit df1778be1a33edffa51d094eeda87c858ded6560 upstream. The null check of `strchr() + 1' is broken, which is always non-null, leading to OOB read. Instead, check the result of strchr(). Signed-off-by: Xi Wang Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ftrace: Call ftrace cleanup module notifier after all other notifiers

2013-03-03T22:03:33Z

commit 8c189ea64eea01ca20d102ddb74d6936dd16c579 upstream. Commit: c1bf08ac "ftrace: Be first to run code modification on modules" changed ftrace module notifier's priority to INT_MAX in order to process the ftrace nops before anything else could touch them (namely kprobes). This was the correct thing to do. Unfortunately, the ftrace module notifier also contains the ftrace clean up code. As opposed to the set up code, this code should be run *after* all the module notifiers have run in case a module is doing correct clean-up and unregisters its ftrace hooks. Basically, ftrace needs to do clean up on module removal, as it needs to know about code being removed so that it doesn't try to modify that code. But after it removes the module from its records, if a ftrace user tries to remove a probe, that removal will fail due as the record of that code segment no longer exists. Nothing really bad happens if the probe removal is called after ftrace did the clean up, but the ftrace removal function will return an error. Correct code (such as kprobes) will produce a WARN_ON() if it fails to remove the probe. As people get annoyed by frivolous warnings, it's best to do the ftrace clean up after everything else. By splitting the ftrace_module_notifier into two notifiers, one that does the module load setup that is run at high priority, and the other that is called for module clean up that is run at low priority, the problem is solved. Reported-by: Frank Ch. Eigler Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

posix-timer: Don't call idr_find() with out-of-range ID

2013-03-03T22:03:33Z

commit e182bb38d7db7494fa5dcd82da17fe0dedf60ecf upstream. When idr_find() was fed a negative ID, it used to look up the ID ignoring the sign bit before recent ("idr: remove MAX_IDR_MASK and move left MAX_IDR_* into idr.c") patch. Now a negative ID triggers a WARN_ON_ONCE(). __lock_timer() feeds timer_id from userland directly to idr_find() without sanitizing it which can trigger the above malfunctions. Add a range check on @timer_id before invoking idr_find() in __lock_timer(). While timer_t is defined as int by all archs at the moment, Andrew worries that it may be defined as a larger type later on. Make the test cover larger integers too so that it at least is guaranteed to not return the wrong timer. Note that WARN_ON_ONCE() in idr_find() on id < 0 is transitional precaution while moving away from ignoring MSB. Once it's gone we can remove the guard as long as timer_t isn't larger than int. Signed-off-by: Tejun Heo Reported-by: Sasha Levin Cc: Andrew Morton Link: http://lkml.kernel.org/r/20130220232412.GL3570@htj.dyndns.org Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

futex: Revert "futex: Mark get_robust_list as deprecated"

2013-02-28T13:38:31Z

commit fe2b05f7ca9f906be61dced5489f63b8b4d7c770 upstream. This reverts commit ec0c4274e33c0373e476b73e01995c53128f1257. get_robust_list() is in use and a removal would break existing user space. With the permission checks in place it's not longer a security hole. Remove the deprecation warnings. Signed-off-by: Thomas Gleixner Cc: Cyrill Gorcunov Cc: Richard Weinberger Cc: akpm@linux-foundation.org Cc: paul.gortmaker@windriver.com Cc: davej@redhat.com Cc: keescook@chromium.org Cc: ebiederm@xmission.com Signed-off-by: Greg Kroah-Hartman

workqueue: un-GPL function delayed_work_timer_fn()

2013-02-28T13:38:29Z

commit 1438ade5670b56d5386c220e1ad4b5a824a1e585 upstream. commit d8e794dfd51c368ed3f686b7f4172830b60ae47b ("workqueue: set delayed_work->timer function on initialization") exports function delayed_work_timer_fn() only for GPL modules. This makes delayed-works unusable for non-GPL modules, because initialization macro now requires GPL symbol. For example schedule_delayed_work() available for non-GPL. Signed-off-by: Konstantin Khlebnikov Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

hrtimer: Prevent hrtimer_enqueue_reprogram race

2013-02-28T13:38:29Z

commit b22affe0aef429d657bc6505aacb1c569340ddd2 upstream. hrtimer_enqueue_reprogram contains a race which could result in timer.base switch during unlock/lock sequence. hrtimer_enqueue_reprogram is releasing the lock protecting the timer base for calling raise_softirq_irqsoff() due to a lock ordering issue versus rq->lock. If during that time another CPU calls __hrtimer_start_range_ns() on the same hrtimer, the timer base might switch, before the current CPU can lock base->lock again and therefor the unlock_timer_base() call will unlock the wrong lock. [ tglx: Added comment and massaged changelog ] Signed-off-by: Leonid Shatz Signed-off-by: Izik Eidus Cc: Andrea Arcangeli Link: http://lkml.kernel.org/r/1359981217-389-1-git-send-email-izik.eidus@ravellosystems.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

posix-cpu-timers: Fix nanosleep task_struct leak

2013-02-28T13:38:28Z

commit e6c42c295e071dd74a66b5a9fcf4f44049888ed8 upstream. The trinity fuzzer triggered a task_struct reference leak via clock_nanosleep with CPU_TIMERs. do_cpu_nanosleep() calls posic_cpu_timer_create(), but misses a corresponding posix_cpu_timer_del() which leads to the task_struct reference leak. Reported-and-tested-by: Tommi Rantala Signed-off-by: Stanislaw Gruszka Cc: Dave Jones Cc: John Stultz Cc: Oleg Nesterov Link: http://lkml.kernel.org/r/20130215100810.GF4392@redhat.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman