user/sven/linux.git/kernel, branch v4.9.32

cpufreq: schedutil: Fix per-CPU structure initialization in sugov_start()

2017-06-14T13:06:05Z

commit 4296f23ed49a15d36949458adcc66ff993dee2a8 upstream. sugov_start() only initializes struct sugov_cpu per-CPU structures for shared policies, but it should do that for single-CPU policies too. That in particular makes the IO-wait boost mechanism work in the cases when cpufreq policies correspond to individual CPUs. Fixes: 21ca6d2c52f8 (cpufreq: schedutil: Add iowait boosting) Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman

cpufreq: schedutil: move cached_raw_freq to struct sugov_policy

2017-06-14T13:06:05Z

commit 6c4f0fa643cb9e775dcc976e3db00d649468ff1d upstream. cached_raw_freq applies to the entire cpufreq policy and not individual CPUs. Apart from wasting per-cpu memory, it is actually wrong to keep it in struct sugov_cpu as we may end up comparing next_freq with a stale cached_raw_freq of a random CPU. Move cached_raw_freq to struct sugov_policy. Fixes: 5cbea46984d6 (cpufreq: schedutil: map raw required frequency to driver frequency) Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman

cpu/hotplug: Drop the device lock on error

2017-06-14T13:06:04Z

commit 40da1b11f01e43aad1aa6cea64681b6125e8a2a7 upstream. If a custom CPU target is specified and that one is not available _or_ can't be interrupted then the code returns to userland without dropping a lock as notices by lockdep: |echo 133 > /sys/devices/system/cpu/cpu7/hotplug/target | ================================================ | [ BUG: lock held when returning to user space! ] | ------------------------------------------------ | bash/503 is leaving the kernel with locks still held! | 1 lock held by bash/503: | #0: (device_hotplug_lock){+.+...}, at: [] lock_device_hotplug_sysfs+0x10/0x40 So release the lock then. Fixes: 757c989b9994 ("cpu/hotplug: Make target state writeable") Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Link: http://lkml.kernel.org/r/20170602142714.3ogo25f2wbq6fjpj@linutronix.de Signed-off-by: Greg Kroah-Hartman

perf/core: Drop kernel samples even though :u is specified

2017-06-14T13:06:03Z

commit cc1582c231ea041fbc68861dfaf957eaf902b829 upstream. When doing sampling, for example: perf record -e cycles:u ... On workloads that do a lot of kernel entry/exits we see kernel samples, even though :u is specified. This is due to skid existing. This might be a security issue because it can leak kernel addresses even though kernel sampling support is disabled. The patch drops the kernel samples if exclude_kernel is specified. For example, test on Haswell desktop: perf record -e cycles:u perf report --stdio Before patch applied: 99.77% mgen mgen [.] buf_read 0.20% mgen mgen [.] rand_buf_init 0.01% mgen [kernel.vmlinux] [k] apic_timer_interrupt 0.00% mgen mgen [.] last_free_elem 0.00% mgen libc-2.23.so [.] __random_r 0.00% mgen libc-2.23.so [.] _int_malloc 0.00% mgen mgen [.] rand_array_init 0.00% mgen [kernel.vmlinux] [k] page_fault 0.00% mgen libc-2.23.so [.] __random 0.00% mgen libc-2.23.so [.] __strcasestr 0.00% mgen ld-2.23.so [.] strcmp 0.00% mgen ld-2.23.so [.] _dl_start 0.00% mgen libc-2.23.so [.] sched_setaffinity@@GLIBC_2.3.4 0.00% mgen ld-2.23.so [.] _start We can see kernel symbols apic_timer_interrupt and page_fault. After patch applied: 99.79% mgen mgen [.] buf_read 0.19% mgen mgen [.] rand_buf_init 0.00% mgen libc-2.23.so [.] __random_r 0.00% mgen mgen [.] rand_array_init 0.00% mgen mgen [.] last_free_elem 0.00% mgen libc-2.23.so [.] vfprintf 0.00% mgen libc-2.23.so [.] rand 0.00% mgen libc-2.23.so [.] __random 0.00% mgen libc-2.23.so [.] _int_malloc 0.00% mgen libc-2.23.so [.] _IO_doallocbuf 0.00% mgen ld-2.23.so [.] do_lookup_x 0.00% mgen ld-2.23.so [.] open_verify.constprop.7 0.00% mgen ld-2.23.so [.] _dl_important_hwcaps 0.00% mgen libc-2.23.so [.] sched_setaffinity@@GLIBC_2.3.4 0.00% mgen ld-2.23.so [.] _start There are only userspace symbols. Signed-off-by: Jin Yao Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: acme@kernel.org Cc: jolsa@kernel.org Cc: kan.liang@intel.com Cc: mark.rutland@arm.com Cc: will.deacon@arm.com Cc: yao.jin@intel.com Link: http://lkml.kernel.org/r/1495706947-3744-1-git-send-email-yao.jin@linux.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

cpuset: consider dying css as offline

2017-06-14T13:06:00Z

commit 41c25707d21716826e3c1f60967f5550610ec1c9 upstream. In most cases, a cgroup controller don't care about the liftimes of cgroups. For the controller, a css becomes online when ->css_online() is called on it and offline when ->css_offline() is called. However, cpuset is special in that the user interface it exposes cares whether certain cgroups exist or not. Combined with the RCU delay between cgroup removal and css offlining, this can lead to user visible behavior oddities where operations which should succeed after cgroup removals fail for some time period. The effects of cgroup removals are delayed when seen from userland. This patch adds css_is_dying() which tests whether offline is pending and updates is_cpuset_online() so that the function returns false also while offline is pending. This gets rid of the userland visible delays. Signed-off-by: Tejun Heo Reported-by: Daniel Jordan Link: http://lkml.kernel.org/r/327ca1f5-7957-fbb9-9e5f-9ba149d40ba2@oracle.com Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

cgroup: Prevent kill_css() from being called more than once

2017-06-14T13:06:00Z

commit 33c35aa4817864e056fd772230b0c6b552e36ea2 upstream. The kill_css() function may be called more than once under the condition that the css was killed but not physically removed yet followed by the removal of the cgroup that is hosting the css. This patch prevents any harmm from being done when that happens. Signed-off-by: Waiman Long Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

ptrace: Properly initialize ptracer_cred on fork

2017-06-14T13:05:54Z

commit c70d9d809fdeecedb96972457ee45c49a232d97f upstream. When I introduced ptracer_cred I failed to consider the weirdness of fork where the task_struct copies the old value by default. This winds up leaving ptracer_cred set even when a process forks and the child process does not wind up being ptraced. Because ptracer_cred is not set on non-ptraced processes whose parents were ptraced this has broken the ability of the enlightenment window manager to start setuid children. Fix this by properly initializing ptracer_cred in ptrace_init_task This must be done with a little bit of care to preserve the current value of ptracer_cred when ptrace carries through fork. Re-reading the ptracer_cred from the ptracing process at this point is inconsistent with how PT_PTRACE_CAP has been maintained all of these years. Tested-by: Takashi Iwai Fixes: 64b875f7ac8a ("ptrace: Capture the ptracer's creds not PT_PTRACE_CAP") Signed-off-by: "Eric W. Biederman" Signed-off-by: Greg Kroah-Hartman

tracing/kprobes: Enforce kprobes teardown after testing

2017-05-25T13:44:47Z

commit 30e7d894c1478c88d50ce94ddcdbd7f9763d9cdd upstream. Enabling the tracer selftest triggers occasionally the warning in text_poke(), which warns when the to be modified page is not marked reserved. The reason is that the tracer selftest installs kprobes on functions marked __init for testing. These probes are removed after the tests, but that removal schedules the delayed kprobes_optimizer work, which will do the actual text poke. If the work is executed after the init text is freed, then the warning triggers. The bug can be reproduced reliably when the work delay is increased. Flush the optimizer work and wait for the optimizing/unoptimizing lists to become empty before returning from the kprobes tracer selftest. That ensures that all operations which were queued due to the probes removal have completed. Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.home Signed-off-by: Thomas Gleixner Acked-by: Masami Hiramatsu Fixes: 6274de498 ("kprobes: Support delayed unoptimizing") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

genirq: Fix chained interrupt data ordering

2017-05-25T13:44:46Z

commit 2c4569ca26986d18243f282dd727da27e9adae4c upstream. irq_set_chained_handler_and_data() sets up the chained interrupt and then stores the handler data. That's racy against an immediate interrupt which gets handled before the store of the handler data happened. The handler will dereference a NULL pointer and crash. Cure it by storing handler data before installing the chained handler. Reported-by: Borislav Petkov Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

stackprotector: Increase the per-task stack canary's random range from 32 bits to 64 bits on 64-bit platforms

2017-05-25T13:44:46Z

commit 5ea30e4e58040cfd6434c2f33dc3ea76e2c15b05 upstream. The stack canary is an 'unsigned long' and should be fully initialized to random data rather than only 32 bits of random data. Signed-off-by: Daniel Micay Acked-by: Arjan van de Ven Acked-by: Rik van Riel Acked-by: Kees Cook Cc: Arjan van Ven Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170504133209.3053-1-danielmicay@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman