linux-stable.git/include/linux, branch v4.14.76 Linux kernel stable tree virtio_balloon: fix deadlock on OOM 2018-10-13T07:27:30+00:00 Michael S. Tsirkin mst@redhat.com 2017-10-13T13:11:48+00:00 7f42eada5e3fd87ed15efba117e1c792a9fbdd0a commit c7cdff0e864713a089d7cb3a2b1136ba9a54881a upstream. fill_balloon doing memory allocations under balloon_lock can cause a deadlock when leak_balloon is called from virtballoon_oom_notify and tries to take same lock. To fix, split page allocation and enqueue and do allocations outside the lock. Here's a detailed analysis of the deadlock by Tetsuo Handa: In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to serialize against fill_balloon(). But in fill_balloon(), alloc_page(GFP_HIGHUSER[_MOVABLE] | __GFP_NOMEMALLOC | __GFP_NORETRY) is called with vb->balloon_lock mutex held. Since GFP_HIGHUSER[_MOVABLE] implies __GFP_DIRECT_RECLAIM | __GFP_IO | __GFP_FS, despite __GFP_NORETRY is specified, this allocation attempt might indirectly depend on somebody else's __GFP_DIRECT_RECLAIM memory allocation. And such indirect __GFP_DIRECT_RECLAIM memory allocation might call leak_balloon() via virtballoon_oom_notify() via blocking_notifier_call_chain() callback via out_of_memory() when it reached __alloc_pages_may_oom() and held oom_lock mutex. Since vb->balloon_lock mutex is already held by fill_balloon(), it will cause OOM lockup. Thread1 Thread2 fill_balloon() takes a balloon_lock balloon_page_enqueue() alloc_page(GFP_HIGHUSER_MOVABLE) direct reclaim (__GFP_FS context) takes a fs lock waits for that fs lock alloc_page(GFP_NOFS) __alloc_pages_may_oom() takes the oom_lock out_of_memory() blocking_notifier_call_chain() leak_balloon() tries to take that balloon_lock and deadlocks Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Michal Hocko <mhocko@suse.com> Cc: Wei Wang <wei.w.wang@intel.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c7cdff0e864713a089d7cb3a2b1136ba9a54881a upstream.

fill_balloon doing memory allocations under balloon_lock
can cause a deadlock when leak_balloon is called from
virtballoon_oom_notify and tries to take same lock.

To fix, split page allocation and enqueue and do allocations outside the lock.

Here's a detailed analysis of the deadlock by Tetsuo Handa:

In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to
serialize against fill_balloon(). But in fill_balloon(),
alloc_page(GFP_HIGHUSER[_MOVABLE] | __GFP_NOMEMALLOC | __GFP_NORETRY) is
called with vb->balloon_lock mutex held. Since GFP_HIGHUSER[_MOVABLE]
implies __GFP_DIRECT_RECLAIM | __GFP_IO | __GFP_FS, despite __GFP_NORETRY
is specified, this allocation attempt might indirectly depend on somebody
else's __GFP_DIRECT_RECLAIM memory allocation. And such indirect
__GFP_DIRECT_RECLAIM memory allocation might call leak_balloon() via
virtballoon_oom_notify() via blocking_notifier_call_chain() callback via
out_of_memory() when it reached __alloc_pages_may_oom() and held oom_lock
mutex. Since vb->balloon_lock mutex is already held by fill_balloon(), it
will cause OOM lockup.

  Thread1                                       Thread2
    fill_balloon()
      takes a balloon_lock
      balloon_page_enqueue()
        alloc_page(GFP_HIGHUSER_MOVABLE)
          direct reclaim (__GFP_FS context)       takes a fs lock
            waits for that fs lock                  alloc_page(GFP_NOFS)
                                                      __alloc_pages_may_oom()
                                                        takes the oom_lock
                                                        out_of_memory()
                                                          blocking_notifier_call_chain()
                                                            leak_balloon()
                                                              tries to take that balloon_lock and deadlocks

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm: migration: fix migration of huge PMD shared pages 2018-10-13T07:27:22+00:00 Mike Kravetz mike.kravetz@oracle.com 2018-10-05T22:51:29+00:00 5f4f5b1f4491627f83d6b1bd2ac7b7c5b87e5f0e commit 017b1660df89f5fb4bfe66c34e35f7d2031100c7 upstream. The page migration code employs try_to_unmap() to try and unmap the source page. This is accomplished by using rmap_walk to find all vmas where the page is mapped. This search stops when page mapcount is zero. For shared PMD huge pages, the page map count is always 1 no matter the number of mappings. Shared mappings are tracked via the reference count of the PMD page. Therefore, try_to_unmap stops prematurely and does not completely unmap all mappings of the source page. This problem can result is data corruption as writes to the original source page can happen after contents of the page are copied to the target page. Hence, data is lost. This problem was originally seen as DB corruption of shared global areas after a huge page was soft offlined due to ECC memory errors. DB developers noticed they could reproduce the issue by (hotplug) offlining memory used to back huge pages. A simple testcase can reproduce the problem by creating a shared PMD mapping (note that this must be at least PUD_SIZE in size and PUD_SIZE aligned (1GB on x86)), and using migrate_pages() to migrate process pages between nodes while continually writing to the huge pages being migrated. To fix, have the try_to_unmap_one routine check for huge PMD sharing by calling huge_pmd_unshare for hugetlbfs huge pages. If it is a shared mapping it will be 'unshared' which removes the page table entry and drops the reference on the PMD page. After this, flush caches and TLB. mmu notifiers are called before locking page tables, but we can not be sure of PMD sharing until page tables are locked. Therefore, check for the possibility of PMD sharing before locking so that notifiers can prepare for the worst possible case. Link: http://lkml.kernel.org/r/20180823205917.16297-2-mike.kravetz@oracle.com [mike.kravetz@oracle.com: make _range_in_vma() a static inline] Link: http://lkml.kernel.org/r/6063f215-a5c8-2f0c-465a-2c515ddc952d@oracle.com Fixes: 39dde65c9940 ("shared page table for hugetlb page") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 017b1660df89f5fb4bfe66c34e35f7d2031100c7 upstream.

The page migration code employs try_to_unmap() to try and unmap the source
page.  This is accomplished by using rmap_walk to find all vmas where the
page is mapped.  This search stops when page mapcount is zero.  For shared
PMD huge pages, the page map count is always 1 no matter the number of
mappings.  Shared mappings are tracked via the reference count of the PMD
page.  Therefore, try_to_unmap stops prematurely and does not completely
unmap all mappings of the source page.

This problem can result is data corruption as writes to the original
source page can happen after contents of the page are copied to the target
page.  Hence, data is lost.

This problem was originally seen as DB corruption of shared global areas
after a huge page was soft offlined due to ECC memory errors.  DB
developers noticed they could reproduce the issue by (hotplug) offlining
memory used to back huge pages.  A simple testcase can reproduce the
problem by creating a shared PMD mapping (note that this must be at least
PUD_SIZE in size and PUD_SIZE aligned (1GB on x86)), and using
migrate_pages() to migrate process pages between nodes while continually
writing to the huge pages being migrated.

To fix, have the try_to_unmap_one routine check for huge PMD sharing by
calling huge_pmd_unshare for hugetlbfs huge pages.  If it is a shared
mapping it will be 'unshared' which removes the page table entry and drops
the reference on the PMD page.  After this, flush caches and TLB.

mmu notifiers are called before locking page tables, but we can not be
sure of PMD sharing until page tables are locked.  Therefore, check for
the possibility of PMD sharing before locking so that notifiers can
prepare for the worst possible case.

Link: http://lkml.kernel.org/r/20180823205917.16297-2-mike.kravetz@oracle.com
[mike.kravetz@oracle.com: make _range_in_vma() a static inline]
  Link: http://lkml.kernel.org/r/6063f215-a5c8-2f0c-465a-2c515ddc952d@oracle.com
Fixes: 39dde65c9940 ("shared page table for hugetlb page")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm/arm64: smccc-1.1: Handle function result as parameters 2018-10-04T00:00:59+00:00 Marc Zyngier marc.zyngier@arm.com 2018-08-24T14:08:30+00:00 647b6d4ff699f841db598f378b0deec2e0b41c2f [ Upstream commit 755a8bf5579d22eb5636685c516d8dede799e27b ] If someone has the silly idea to write something along those lines: extern u64 foo(void); void bar(struct arm_smccc_res *res) { arm_smccc_1_1_smc(0xbad, foo(), res); } they are in for a surprise, as this gets compiled as: 0000000000000588 <bar>: 588: a9be7bfd stp x29, x30, [sp, #-32]! 58c: 910003fd mov x29, sp 590: f9000bf3 str x19, [sp, #16] 594: aa0003f3 mov x19, x0 598: aa1e03e0 mov x0, x30 59c: 94000000 bl 0 <_mcount> 5a0: 94000000 bl 0 <foo> 5a4: aa0003e1 mov x1, x0 5a8: d4000003 smc #0x0 5ac: b4000073 cbz x19, 5b8 <bar+0x30> 5b0: a9000660 stp x0, x1, [x19] 5b4: a9010e62 stp x2, x3, [x19, #16] 5b8: f9400bf3 ldr x19, [sp, #16] 5bc: a8c27bfd ldp x29, x30, [sp], #32 5c0: d65f03c0 ret 5c4: d503201f nop The call to foo "overwrites" the x0 register for the return value, and we end up calling the wrong secure service. A solution is to evaluate all the parameters before assigning anything to specific registers, leading to the expected result: 0000000000000588 <bar>: 588: a9be7bfd stp x29, x30, [sp, #-32]! 58c: 910003fd mov x29, sp 590: f9000bf3 str x19, [sp, #16] 594: aa0003f3 mov x19, x0 598: aa1e03e0 mov x0, x30 59c: 94000000 bl 0 <_mcount> 5a0: 94000000 bl 0 <foo> 5a4: aa0003e1 mov x1, x0 5a8: d28175a0 mov x0, #0xbad 5ac: d4000003 smc #0x0 5b0: b4000073 cbz x19, 5bc <bar+0x34> 5b4: a9000660 stp x0, x1, [x19] 5b8: a9010e62 stp x2, x3, [x19, #16] 5bc: f9400bf3 ldr x19, [sp, #16] 5c0: a8c27bfd ldp x29, x30, [sp], #32 5c4: d65f03c0 ret Reported-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 755a8bf5579d22eb5636685c516d8dede799e27b ]

If someone has the silly idea to write something along those lines:

	extern u64 foo(void);

	void bar(struct arm_smccc_res *res)
	{
		arm_smccc_1_1_smc(0xbad, foo(), res);
	}

they are in for a surprise, as this gets compiled as:

	0000000000000588 <bar>:
	 588:   a9be7bfd        stp     x29, x30, [sp, #-32]!
	 58c:   910003fd        mov     x29, sp
	 590:   f9000bf3        str     x19, [sp, #16]
	 594:   aa0003f3        mov     x19, x0
	 598:   aa1e03e0        mov     x0, x30
	 59c:   94000000        bl      0 <_mcount>
	 5a0:   94000000        bl      0 <foo>
	 5a4:   aa0003e1        mov     x1, x0
	 5a8:   d4000003        smc     #0x0
	 5ac:   b4000073        cbz     x19, 5b8 <bar+0x30>
	 5b0:   a9000660        stp     x0, x1, [x19]
	 5b4:   a9010e62        stp     x2, x3, [x19, #16]
	 5b8:   f9400bf3        ldr     x19, [sp, #16]
	 5bc:   a8c27bfd        ldp     x29, x30, [sp], #32
	 5c0:   d65f03c0        ret
	 5c4:   d503201f        nop

The call to foo "overwrites" the x0 register for the return value,
and we end up calling the wrong secure service.

A solution is to evaluate all the parameters before assigning
anything to specific registers, leading to the expected result:

	0000000000000588 <bar>:
	 588:   a9be7bfd        stp     x29, x30, [sp, #-32]!
	 58c:   910003fd        mov     x29, sp
	 590:   f9000bf3        str     x19, [sp, #16]
	 594:   aa0003f3        mov     x19, x0
	 598:   aa1e03e0        mov     x0, x30
	 59c:   94000000        bl      0 <_mcount>
	 5a0:   94000000        bl      0 <foo>
	 5a4:   aa0003e1        mov     x1, x0
	 5a8:   d28175a0        mov     x0, #0xbad
	 5ac:   d4000003        smc     #0x0
	 5b0:   b4000073        cbz     x19, 5bc <bar+0x34>
	 5b4:   a9000660        stp     x0, x1, [x19]
	 5b8:   a9010e62        stp     x2, x3, [x19, #16]
	 5bc:   f9400bf3        ldr     x19, [sp, #16]
	 5c0:   a8c27bfd        ldp     x29, x30, [sp], #32
	 5c4:   d65f03c0        ret

Reported-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm/arm64: smccc-1.1: Make return values unsigned long 2018-10-04T00:00:59+00:00 Marc Zyngier marc.zyngier@arm.com 2018-08-24T14:08:29+00:00 826d8678cde2a4329d19b96b93e093fa0f4d0883 [ Upstream commit 1d8f574708a3fb6f18c85486d0c5217df893c0cf ] An unfortunate consequence of having a strong typing for the input values to the SMC call is that it also affects the type of the return values, limiting r0 to 32 bits and r{1,2,3} to whatever was passed as an input. Let's turn everything into "unsigned long", which satisfies the requirements of both architectures, and allows for the full range of return values. Reported-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 1d8f574708a3fb6f18c85486d0c5217df893c0cf ]

An unfortunate consequence of having a strong typing for the input
values to the SMC call is that it also affects the type of the
return values, limiting r0 to 32 bits and r{1,2,3} to whatever
was passed as an input.

Let's turn everything into "unsigned long", which satisfies the
requirements of both architectures, and allows for the full
range of return values.

Reported-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hwmon: (ina2xx) fix sysfs shunt resistor read access 2018-10-04T00:00:58+00:00 Lothar Felten lothar.felten@gmail.com 2018-08-14T07:09:37+00:00 0647ce03bd48aac37b055355c168b4a889bcc36b [ Upstream commit 3ad867001c91657c46dcf6656d52eb6080286fd5 ] fix the sysfs shunt resistor read access: return the shunt resistor value, not the calibration register contents. update email address Signed-off-by: Lothar Felten <lothar.felten@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 3ad867001c91657c46dcf6656d52eb6080286fd5 ]

fix the sysfs shunt resistor read access: return the shunt resistor
value, not the calibration register contents.

update email address

Signed-off-by: Lothar Felten <lothar.felten@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
slub: make ->cpu_partial unsigned int 2018-10-04T00:00:55+00:00 Alexey Dobriyan adobriyan@gmail.com 2018-04-05T23:21:10+00:00 1ddc0781c0ce451805b4ee6a5b7521bf9c49d5aa commit e5d9998f3e09359b372a037a6ac55ba235d95d57 upstream. /* * cpu_partial determined the maximum number of objects * kept in the per cpu partial lists of a processor. */ Can't be negative. Link: http://lkml.kernel.org/r/20180305200730.15812-15-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: zhong jiang <zhongjiang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e5d9998f3e09359b372a037a6ac55ba235d95d57 upstream.

	/*
	 * cpu_partial determined the maximum number of objects
	 * kept in the per cpu partial lists of a processor.
	 */

Can't be negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-15-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
posix-timers: Sanitize overrun handling 2018-10-04T00:00:50+00:00 Thomas Gleixner tglx@linutronix.de 2018-06-26T13:21:32+00:00 3e3f075f72bd2dfcd5211bd1ff3919bc118ad4cd [ Upstream commit 78c9c4dfbf8c04883941445a195276bb4bb92c76 ] The posix timer overrun handling is broken because the forwarding functions can return a huge number of overruns which does not fit in an int. As a consequence timer_getoverrun(2) and siginfo::si_overrun can turn into random number generators. The k_clock::timer_forward() callbacks return a 64 bit value now. Make k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal accounting is correct. 3Remove the temporary (int) casts. Add a helper function which clamps the overrun value returned to user space via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value between 0 and INT_MAX. INT_MAX is an indicator for user space that the overrun value has been clamped. Reported-by: Team OWL337 <icytxw@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Link: https://lkml.kernel.org/r/20180626132705.018623573@linutronix.de Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 78c9c4dfbf8c04883941445a195276bb4bb92c76 ]

The posix timer overrun handling is broken because the forwarding functions
can return a huge number of overruns which does not fit in an int. As a
consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
random number generators.

The k_clock::timer_forward() callbacks return a 64 bit value now. Make
k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
accounting is correct. 3Remove the temporary (int) casts.

Add a helper function which clamps the overrun value returned to user space
via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
between 0 and INT_MAX. INT_MAX is an indicator for user space that the
overrun value has been clamped.

Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Link: https://lkml.kernel.org/r/20180626132705.018623573@linutronix.de
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
power: remove possible deadlock when unregistering power_supply 2018-10-04T00:00:47+00:00 Benjamin Tissoires benjamin.tissoires@redhat.com 2018-06-25T07:51:48+00:00 e70f938a605a82c96760ee2afb6f9eac6d0e7088 [ Upstream commit 3ffa6583e24e1ad1abab836d24bfc9d2308074e5 ] If a device gets removed right after having registered a power_supply node, we might enter in a deadlock between the remove call (that has a lock on the parent device) and the deferred register work. Allow the deferred register work to exit without taking the lock when we are in the remove state. Stack trace on a Ubuntu 16.04: [16072.109121] INFO: task kworker/u16:2:1180 blocked for more than 120 seconds. [16072.109127] Not tainted 4.13.0-41-generic #46~16.04.1-Ubuntu [16072.109129] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [16072.109132] kworker/u16:2 D 0 1180 2 0x80000000 [16072.109142] Workqueue: events_power_efficient power_supply_deferred_register_work [16072.109144] Call Trace: [16072.109152] __schedule+0x3d6/0x8b0 [16072.109155] schedule+0x36/0x80 [16072.109158] schedule_preempt_disabled+0xe/0x10 [16072.109161] __mutex_lock.isra.2+0x2ab/0x4e0 [16072.109166] __mutex_lock_slowpath+0x13/0x20 [16072.109168] ? __mutex_lock_slowpath+0x13/0x20 [16072.109171] mutex_lock+0x2f/0x40 [16072.109174] power_supply_deferred_register_work+0x2b/0x50 [16072.109179] process_one_work+0x15b/0x410 [16072.109182] worker_thread+0x4b/0x460 [16072.109186] kthread+0x10c/0x140 [16072.109189] ? process_one_work+0x410/0x410 [16072.109191] ? kthread_create_on_node+0x70/0x70 [16072.109194] ret_from_fork+0x35/0x40 [16072.109199] INFO: task test:2257 blocked for more than 120 seconds. [16072.109202] Not tainted 4.13.0-41-generic #46~16.04.1-Ubuntu [16072.109204] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [16072.109206] test D 0 2257 2256 0x00000004 [16072.109208] Call Trace: [16072.109211] __schedule+0x3d6/0x8b0 [16072.109215] schedule+0x36/0x80 [16072.109218] schedule_timeout+0x1f3/0x360 [16072.109221] ? check_preempt_curr+0x5a/0xa0 [16072.109224] ? ttwu_do_wakeup+0x1e/0x150 [16072.109227] wait_for_completion+0xb4/0x140 [16072.109230] ? wait_for_completion+0xb4/0x140 [16072.109233] ? wake_up_q+0x70/0x70 [16072.109236] flush_work+0x129/0x1e0 [16072.109240] ? worker_detach_from_pool+0xb0/0xb0 [16072.109243] __cancel_work_timer+0x10f/0x190 [16072.109247] ? device_del+0x264/0x310 [16072.109250] ? __wake_up+0x44/0x50 [16072.109253] cancel_delayed_work_sync+0x13/0x20 [16072.109257] power_supply_unregister+0x37/0xb0 [16072.109260] devm_power_supply_release+0x11/0x20 [16072.109263] release_nodes+0x110/0x200 [16072.109266] devres_release_group+0x7c/0xb0 [16072.109274] wacom_remove+0xc2/0x110 [wacom] [16072.109279] hid_device_remove+0x6e/0xd0 [hid] [16072.109284] device_release_driver_internal+0x158/0x210 [16072.109288] device_release_driver+0x12/0x20 [16072.109291] bus_remove_device+0xec/0x160 [16072.109293] device_del+0x1de/0x310 [16072.109298] hid_destroy_device+0x27/0x60 [hid] [16072.109303] usbhid_disconnect+0x51/0x70 [usbhid] [16072.109308] usb_unbind_interface+0x77/0x270 [16072.109311] device_release_driver_internal+0x158/0x210 [16072.109315] device_release_driver+0x12/0x20 [16072.109318] usb_driver_release_interface+0x77/0x80 [16072.109321] proc_ioctl+0x20f/0x250 [16072.109325] usbdev_do_ioctl+0x57f/0x1140 [16072.109327] ? __wake_up+0x44/0x50 [16072.109331] usbdev_ioctl+0xe/0x20 [16072.109336] do_vfs_ioctl+0xa4/0x600 [16072.109339] ? vfs_write+0x15a/0x1b0 [16072.109343] SyS_ioctl+0x79/0x90 [16072.109347] entry_SYSCALL_64_fastpath+0x24/0xab [16072.109349] RIP: 0033:0x7f20da807f47 [16072.109351] RSP: 002b:00007ffc422ae398 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [16072.109353] RAX: ffffffffffffffda RBX: 00000000010b8560 RCX: 00007f20da807f47 [16072.109355] RDX: 00007ffc422ae3a0 RSI: 00000000c0105512 RDI: 0000000000000009 [16072.109356] RBP: 0000000000000000 R08: 00007ffc422ae3e0 R09: 0000000000000010 [16072.109357] R10: 00000000000000a6 R11: 0000000000000246 R12: 0000000000000000 [16072.109359] R13: 00000000010b8560 R14: 00007ffc422ae2e0 R15: 0000000000000000 Reported-and-tested-by: Richard Hughes <rhughes@redhat.com> Tested-by: Aaron Skomra <Aaron.Skomra@wacom.com> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Fixes: 7f1a57fdd6cb ("power_supply: Fix possible NULL pointer dereference on early uevent") Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 3ffa6583e24e1ad1abab836d24bfc9d2308074e5 ]

If a device gets removed right after having registered a power_supply node,
we might enter in a deadlock between the remove call (that has a lock on
the parent device) and the deferred register work.

Allow the deferred register work to exit without taking the lock when
we are in the remove state.

Stack trace on a Ubuntu 16.04:

[16072.109121] INFO: task kworker/u16:2:1180 blocked for more than 120 seconds.
[16072.109127]       Not tainted 4.13.0-41-generic #46~16.04.1-Ubuntu
[16072.109129] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[16072.109132] kworker/u16:2   D    0  1180      2 0x80000000
[16072.109142] Workqueue: events_power_efficient power_supply_deferred_register_work
[16072.109144] Call Trace:
[16072.109152]  __schedule+0x3d6/0x8b0
[16072.109155]  schedule+0x36/0x80
[16072.109158]  schedule_preempt_disabled+0xe/0x10
[16072.109161]  __mutex_lock.isra.2+0x2ab/0x4e0
[16072.109166]  __mutex_lock_slowpath+0x13/0x20
[16072.109168]  ? __mutex_lock_slowpath+0x13/0x20
[16072.109171]  mutex_lock+0x2f/0x40
[16072.109174]  power_supply_deferred_register_work+0x2b/0x50
[16072.109179]  process_one_work+0x15b/0x410
[16072.109182]  worker_thread+0x4b/0x460
[16072.109186]  kthread+0x10c/0x140
[16072.109189]  ? process_one_work+0x410/0x410
[16072.109191]  ? kthread_create_on_node+0x70/0x70
[16072.109194]  ret_from_fork+0x35/0x40
[16072.109199] INFO: task test:2257 blocked for more than 120 seconds.
[16072.109202]       Not tainted 4.13.0-41-generic #46~16.04.1-Ubuntu
[16072.109204] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[16072.109206] test            D    0  2257   2256 0x00000004
[16072.109208] Call Trace:
[16072.109211]  __schedule+0x3d6/0x8b0
[16072.109215]  schedule+0x36/0x80
[16072.109218]  schedule_timeout+0x1f3/0x360
[16072.109221]  ? check_preempt_curr+0x5a/0xa0
[16072.109224]  ? ttwu_do_wakeup+0x1e/0x150
[16072.109227]  wait_for_completion+0xb4/0x140
[16072.109230]  ? wait_for_completion+0xb4/0x140
[16072.109233]  ? wake_up_q+0x70/0x70
[16072.109236]  flush_work+0x129/0x1e0
[16072.109240]  ? worker_detach_from_pool+0xb0/0xb0
[16072.109243]  __cancel_work_timer+0x10f/0x190
[16072.109247]  ? device_del+0x264/0x310
[16072.109250]  ? __wake_up+0x44/0x50
[16072.109253]  cancel_delayed_work_sync+0x13/0x20
[16072.109257]  power_supply_unregister+0x37/0xb0
[16072.109260]  devm_power_supply_release+0x11/0x20
[16072.109263]  release_nodes+0x110/0x200
[16072.109266]  devres_release_group+0x7c/0xb0
[16072.109274]  wacom_remove+0xc2/0x110 [wacom]
[16072.109279]  hid_device_remove+0x6e/0xd0 [hid]
[16072.109284]  device_release_driver_internal+0x158/0x210
[16072.109288]  device_release_driver+0x12/0x20
[16072.109291]  bus_remove_device+0xec/0x160
[16072.109293]  device_del+0x1de/0x310
[16072.109298]  hid_destroy_device+0x27/0x60 [hid]
[16072.109303]  usbhid_disconnect+0x51/0x70 [usbhid]
[16072.109308]  usb_unbind_interface+0x77/0x270
[16072.109311]  device_release_driver_internal+0x158/0x210
[16072.109315]  device_release_driver+0x12/0x20
[16072.109318]  usb_driver_release_interface+0x77/0x80
[16072.109321]  proc_ioctl+0x20f/0x250
[16072.109325]  usbdev_do_ioctl+0x57f/0x1140
[16072.109327]  ? __wake_up+0x44/0x50
[16072.109331]  usbdev_ioctl+0xe/0x20
[16072.109336]  do_vfs_ioctl+0xa4/0x600
[16072.109339]  ? vfs_write+0x15a/0x1b0
[16072.109343]  SyS_ioctl+0x79/0x90
[16072.109347]  entry_SYSCALL_64_fastpath+0x24/0xab
[16072.109349] RIP: 0033:0x7f20da807f47
[16072.109351] RSP: 002b:00007ffc422ae398 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[16072.109353] RAX: ffffffffffffffda RBX: 00000000010b8560 RCX: 00007f20da807f47
[16072.109355] RDX: 00007ffc422ae3a0 RSI: 00000000c0105512 RDI: 0000000000000009
[16072.109356] RBP: 0000000000000000 R08: 00007ffc422ae3e0 R09: 0000000000000010
[16072.109357] R10: 00000000000000a6 R11: 0000000000000246 R12: 0000000000000000
[16072.109359] R13: 00000000010b8560 R14: 00007ffc422ae2e0 R15: 0000000000000000

Reported-and-tested-by: Richard Hughes <rhughes@redhat.com>
Tested-by: Aaron Skomra <Aaron.Skomra@wacom.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Fixes: 7f1a57fdd6cb ("power_supply: Fix possible NULL pointer dereference on early uevent")
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
evm: Don't deadlock if a crypto algorithm is unavailable 2018-09-26T06:38:09+00:00 Matthew Garrett mjg59@google.com 2018-06-08T21:57:42+00:00 c818695c71068a30580064fc65fea51e074f57bf [ Upstream commit e2861fa71641c6414831d628a1f4f793b6562580 ] When EVM attempts to appraise a file signed with a crypto algorithm the kernel doesn't have support for, it will cause the kernel to trigger a module load. If the EVM policy includes appraisal of kernel modules this will in turn call back into EVM - since EVM is holding a lock until the crypto initialisation is complete, this triggers a deadlock. Add a CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag in the EVM case in order to fail gracefully with an error message instead of deadlocking. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit e2861fa71641c6414831d628a1f4f793b6562580 ]

When EVM attempts to appraise a file signed with a crypto algorithm the
kernel doesn't have support for, it will cause the kernel to trigger a
module load. If the EVM policy includes appraisal of kernel modules this
will in turn call back into EVM - since EVM is holding a lock until the
crypto initialisation is complete, this triggers a deadlock. Add a
CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag
in the EVM case in order to fail gracefully with an error message
instead of deadlocking.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mlx5: Fix use-after-free in self-healing flow 2018-09-26T06:37:57+00:00 Jack Morgenstein jackm@dev.mellanox.co.il 2018-08-05T06:19:33+00:00 47f74ff0024397550a2fe5ecef7db3638223bafb [ Upstream commit 76d5581c870454be5f1f1a106c57985902e7ea20 ] When the mlx5 health mechanism detects a problem while the driver is in the middle of init_one or remove_one, the driver needs to prevent the health mechanism from scheduling future work; if future work is scheduled, there is a problem with use-after-free: the system WQ tries to run the work item (which has been freed) at the scheduled future time. Prevent this by disabling work item scheduling in the health mechanism when the driver is in the middle of init_one() or remove_one(). Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters") Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Reviewed-by: Feras Daoud <ferasda@mellanox.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 76d5581c870454be5f1f1a106c57985902e7ea20 ]

When the mlx5 health mechanism detects a problem while the driver
is in the middle of init_one or remove_one, the driver needs to prevent
the health mechanism from scheduling future work; if future work
is scheduled, there is a problem with use-after-free: the system WQ
tries to run the work item (which has been freed) at the scheduled
future time.

Prevent this by disabling work item scheduling in the health mechanism
when the driver is in the middle of init_one() or remove_one().

Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Reviewed-by: Feras Daoud <ferasda@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>