Eric W. Biederman 040757f738 ucount: Remove the atomicity from ucount->count ...

Always increment/decrement ucount->count under the ucounts_lock.  The
increments are there already and moving the decrements there means the
locking logic of the code is simpler.  This simplification in the
locking logic fixes a race between put_ucounts and get_ucounts that
could result in a use-after-free because the count could go zero then
be found by get_ucounts and then be freed by put_ucounts.

A bug presumably this one was found by a combination of syzkaller and
KASAN.  JongWhan Kim reported the syzkaller failure and Dmitry Vyukov
spotted the race in the code.

Cc: stable@vger.kernel.org
Fixes: f6b2db1a3e8d ("userns: Make the count of user namespaces per user")
Reported-by: JongHwan Kim <zzoru007@gmail.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

2017-03-06 15:26:37 -06:00

..

bpf

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-03-04 17:31:39 -08:00

cgroup

sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>

2017-03-03 01:45:39 +01:00

configs

config: android-base: enable hardened usercopy and kernel ASLR

2017-02-27 18:43:46 -08:00

debug

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

events

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>

2017-03-02 08:42:36 +01:00

gcov

gcov: add support for gcc version >= 6

2016-07-15 14:54:27 +09:00

irq

sched/headers: Prepare to move the get_task_struct()/put_task_struct() and related APIs from <linux/sched.h> to <linux/sched/task.h>

2017-03-02 08:42:40 +01:00

livepatch

livepatch/module: make TAINT_LIVEPATCH module-specific

2016-08-26 14:42:08 +02:00

locking

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

power

Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-03-03 10:16:38 -08:00

printk

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>

2017-03-02 08:42:36 +01:00

rcu

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

sched

sched/headers: Move cputime functionality from <linux/sched.h> and <linux/cputime.h> into <linux/sched/cputime.h>

2017-03-03 01:45:22 +01:00

time

sched/headers: Prepare to move exit_files() and exit_itimers() from <linux/sched.h> to <linux/sched/task.h>

2017-03-02 08:42:40 +01:00

trace

sched/headers: Prepare to use <linux/rcuupdate.h> instead of <linux/rculist.h> in <linux/sched.h>

2017-03-02 08:42:38 +01:00

.gitignore

…

acct.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

async.c

…

audit_fsnotify.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-12-17 18:44:00 -08:00

audit_tree.c

Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit

2017-01-05 23:06:06 -08:00

audit_watch.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-12-17 18:44:00 -08:00

audit.c

Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit

2017-02-21 13:25:50 -08:00

audit.h

Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit

2017-02-21 13:25:50 -08:00

auditfilter.c

audit: add support for session ID user filter

2016-11-29 15:10:12 -05:00

auditsc.c

Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit

2017-02-21 13:25:50 -08:00

backtracetest.c

…

bounds.c

…

capability.c

capability: export has_capability

2017-01-12 07:01:56 -07:00

compat.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

configs.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

context_tracking.c

…

cpu_pm.c

…

cpu.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

crash_dump.c

…

cred.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/coredump.h>

2017-03-02 08:42:28 +01:00

delayacct.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

dma.c

…

elfcore.c

…

exec_domain.c

…

exit.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

extable.c

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2017-02-22 10:15:09 -08:00

fork.c

sched/headers, RCU: Move rcu_copy_process() from <linux/sched/task.h> to kernel/fork.c

2017-03-03 01:43:46 +01:00

freezer.c

freezer, oom: check TIF_MEMDIE on the correct task

2016-07-28 16:07:41 -07:00

futex_compat.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

futex.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h>

2017-03-02 08:42:28 +01:00

groups.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

hung_task.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

irq_work.c

…

jump_label.c

This release has no new tracing features, just clean ups, minor fixes

2017-02-27 13:26:17 -08:00

kallsyms.c

bpf: make jited programs visible in traces

2017-02-17 13:40:05 -05:00

kcmp.c

…

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.locks

locking/mutex: Allow MUTEX_SPIN_ON_OWNER when DEBUG_MUTEXES

2016-10-25 11:31:51 +02:00

Kconfig.preempt

…

kcov.c

kcov: make kcov work properly with KASLR enabled

2016-12-20 09:48:47 -08:00

kexec_core.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

2017-02-22 17:33:34 -08:00

kexec_file.c

ima: on soft reboot, save the measurement list

2016-12-20 09:48:44 -08:00

kexec_internal.h

kexec_file: Allow arch-specific memory walking for kexec_add_buffer

2016-11-30 23:14:57 +11:00

kexec.c

kexec: allow architectures to override boot mapping

2016-08-02 19:35:27 -04:00

kmod.c

sched/headers, vfs/execve: Prepare to move the do_execve*() prototypes from <linux/sched.h> to <linux/binfmts.h>

2017-03-02 08:42:39 +01:00

kprobes.c

powerpc updates for 4.11 part 1.

2017-02-22 10:30:38 -08:00

ksysfs.c

kernel/ksysfs.c: add __ro_after_init to bin_attribute structure

2017-02-24 17:46:56 -08:00

kthread.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

latencytop.c

sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>

2017-03-02 08:42:39 +01:00

Makefile

cgroup: move cgroup files under kernel/cgroup/

2016-12-27 14:49:05 -05:00

membarrier.c

Fix: Disable sys_membarrier when nohz_full is enabled

2017-01-23 11:32:16 -08:00

memremap.c

mm, devm_memremap_pages: hold device_hotplug lock over mem_hotplug_{begin, done}

2017-02-24 17:46:53 -08:00

module_signing.c

…

module-internal.h

…

module.c

Modules updates for v4.11

2017-02-22 17:08:33 -08:00

notifier.c

kernel/notifier.c: simplify expression

2017-02-24 17:46:56 -08:00

nsproxy.c

…

padata.c

padata: Remove unused but set variables

2016-10-25 11:08:10 +08:00

panic.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

params.c

…

pid_namespace.c

sched/headers: Prepare for the reduction of <linux/sched.h>'s signal API dependency

2017-03-02 08:42:37 +01:00

pid.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

profile.c

sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>

2017-03-02 08:42:39 +01:00

ptrace.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

range.c

…

reboot.c

…

relay.c

lib/vsprintf.c: remove %Z support

2017-02-27 18:43:47 -08:00

resource.c

…

seccomp.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>

2017-03-02 08:42:36 +01:00

signal.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

smp.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/idle.h>

2017-03-02 08:42:26 +01:00

smpboot.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

smpboot.h

…

softirq.c

softirq: Display IRQ_POLL for irq-poll statistics

2016-10-21 15:45:47 -06:00

stacktrace.c

stacktrace, lockdep: Fix address, newline ugliness

2017-02-08 08:21:31 +01:00

stop_machine.c

locking/core, stop_machine: Yield the CPU during stop machine()

2016-11-16 10:15:09 +01:00

sys_ni.c

move aio compat to fs/aio.c

2016-12-22 22:58:37 -05:00

sys.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

sysctl_binary.c

sysctl: add KERN_CONT to deprecated_sysctl_warning()

2016-12-14 16:04:07 -08:00

sysctl.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/coredump.h>

2017-03-02 08:42:28 +01:00

task_work.c

task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works

2016-08-02 19:35:02 -04:00

taskstats.c

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-11-15 10:54:36 -05:00

test_kprobes.c

…

torture.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h>

2017-03-02 08:42:27 +01:00

tracepoint.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

tsacct.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

ucount.c

ucount: Remove the atomicity from ucount->count

2017-03-06 15:26:37 -06:00

uid16.c

sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>

2017-03-02 08:42:31 +01:00

up.c

smp: Add function to execute a function synchronously on a CPU

2016-09-05 13:52:39 +02:00

user_namespace.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>

2017-03-02 08:42:29 +01:00

user-return-notifier.c

…

user.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h>

2017-03-02 08:42:29 +01:00

utsname_sysctl.c

sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>

2017-03-03 01:45:36 +01:00

utsname.c

sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>

2017-03-02 08:42:38 +01:00

watchdog_hld.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

watchdog.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

workqueue_internal.h

…

workqueue.c

time: Remove CONFIG_TIMER_STATS

2017-02-10 11:15:08 +01:00