linux-stable.git/include, branch v3.18.45

mm: remove gup_flags FOLL_WRITE games from __get_user_pages()

2016-10-22T19:48:09+00:00

[ Upstream commit 19be0eaffa3ac7d8eb6784ad9bdbc7d67ed8e619 ]

This is an ancient bug that was actually attempted to be fixed once
(badly) by me eleven years ago in commit 4ceb5db9757a ("Fix
get_user_pages() race for write access") but that was then undone due to
problems on s390 by commit f33ea7f404e5 ("fix get_user_pages bug").

In the meantime, the s390 situation has long been fixed, and we can now
fix it by checking the pte_dirty() bit properly (and do it better).  The
s390 dirty bit was implemented in abf09bed3cce ("s390/mm: implement
software dirty bits") which made it into v3.9.  Earlier kernels will
have to look at the page state itself.

Also, the VM has become more scalable, and what used a purely
theoretical race back then has become easier to trigger.

To fix it, we introduce a new internal FOLL_COW flag to mark the "yes,
we already did a COW" rather than play racy games with FOLL_WRITE that
is very fundamental, and then use the pte dirty flag to validate that
the FOLL_COW flag is still valid.

Reported-and-tested-by: Phil "not Paul" Oester 
Acked-by: Hugh Dickins 
Reviewed-by: Michal Hocko 
Cc: Andy Lutomirski 
Cc: Kees Cook 
Cc: Oleg Nesterov 
Cc: Willy Tarreau 
Cc: Nick Piggin 
Cc: Greg Thelen 
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

fix fault_in_multipages_...() on architectures with no-op access_ok()

2016-10-06T02:40:20+00:00

[ Upstream commit e23d4159b109167126e5bcd7f3775c95de7fee47 ]

Switching iov_iter fault-in to multipages variants has exposed an old
bug in underlying fault_in_multipages_...(); they break if the range
passed to them wraps around.  Normally access_ok() done by callers will
prevent such (and it's a guaranteed EFAULT - ERR_PTR() values fall into
such a range and they should not point to any valid objects).

However, on architectures where userland and kernel live in different
MMU contexts (e.g. s390) access_ok() is a no-op and on those a range
with a wraparound can reach fault_in_multipages_...().

Since any wraparound means EFAULT there, the fix is trivial - turn
those

    while (uaddr <= end)
	    ...
into

    if (unlikely(uaddr > end))
	    return -EFAULT;
    do
	    ...
    while (uaddr <= end);

Reported-by: Jan Stancek 
Tested-by: Jan Stancek 
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Al Viro 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

fanotify: fix list corruption in fanotify_get_response()

2016-10-06T02:40:20+00:00

[ Upstream commit 96d41019e3ac55f6f0115b0ce97e4f24a3d636d2 ]

fanotify_get_response() calls fsnotify_remove_event() when it finds that
group is being released from fanotify_release() (bypass_perm is set).

However the event it removes need not be only in the group's notification
queue but it can have already moved to access_list (userspace read the
event before closing the fanotify instance fd) which is protected by a
different lock.  Thus when fsnotify_remove_event() races with
fanotify_release() operating on access_list, the list can get corrupted.

Fix the problem by moving all the logic removing permission events from
the lists to one place - fanotify_release().

Fixes: 5838d4442bd5 ("fanotify: fix double free of pending permission events")
Link: http://lkml.kernel.org/r/1473797711-14111-3-git-send-email-jack@suse.cz
Signed-off-by: Jan Kara 
Reported-by: Miklos Szeredi 
Tested-by: Miklos Szeredi 
Reviewed-by: Miklos Szeredi 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

fsnotify: add a way to stop queueing events on group shutdown

2016-10-06T02:40:20+00:00

[ Upstream commit 12703dbfeb15402260e7554d32a34ac40c233990 ]

Implement a function that can be called when a group is being shutdown
to stop queueing new events to the group.  Fanotify will use this.

Fixes: 5838d4442bd5 ("fanotify: fix double free of pending permission events")
Link: http://lkml.kernel.org/r/1473797711-14111-2-git-send-email-jack@suse.cz
Signed-off-by: Jan Kara 
Reviewed-by: Miklos Szeredi 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

asm-generic: make get_user() clear the destination on errors

2016-10-06T02:40:20+00:00

[ Upstream commit 9ad18b75c2f6e4a78ce204e79f37781f8815c0fa ]

both for access_ok() failures and for faults halfway through

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro 
Signed-off-by: Sasha Levin

asm-generic: {get,put}_user ptr argument evaluate only 1 time

2016-10-06T02:40:20+00:00

[ Upstream commit a02613a4ba679eacec8251976d02809d533fa717 ]

Current implemantation ptr argument evaluate 2 times.
It'll be an unexpected result.

Changes v5:
Remove unnecessary const.
Changes v4:
Temporary pointer type change to const void*
Changes v3:
Some build error fix.
Changes v2:
Argument x protect.

Signed-off-by: Yoshinori Sato 
Signed-off-by: Sasha Levin

genirq: Provide irq_gc_{lock_irqsave,unlock_irqrestore}() helpers

2016-10-06T02:40:20+00:00

[ Upstream commit ebf9ff753c041b296241990aef76163bbb2cc9c8 ]

Some irqchip drivers need to take the generic chip lock outside of the
irq context.

Provide the irq_gc_{lock_irqsave,unlock_irqrestore}() helpers to allow
one to disable irqs while entering a critical section protected by
gc->lock.

Note that we do not provide optimized version of these helpers for !SMP,
because they are not called from the hot-path.

[ tglx: Added a comment when these helpers should be [not] used ]

Signed-off-by: Boris Brezillon 
Cc: Jason Cooper 
Cc: Marc Zyngier 
Cc: Nicolas Ferre 
Cc: stable@vger.kernel.org
Cc: Alexandre Belloni 
Link: http://lkml.kernel.org/r/1473775109-4192-1-git-send-email-boris.brezillon@free-electrons.com
Signed-off-by: Thomas Gleixner 
Signed-off-by: Sasha Levin

genirq: Generic chip: Change irq_reg_{readl,writel} arguments

2016-10-06T02:40:20+00:00

[ Upstream commit 332fd7c4fef5f3b166e93decb07fd69eb24f7998 ]

Pass in the irq_chip_generic struct so we can use different readl/writel
settings for each irqchip driver, when appropriate.  Compute
(gc->reg_base + reg_offset) in the helper function because this is pretty
much what all callers want to do anyway.

Compile-tested using the following configurations:

    at91_dt_defconfig (CONFIG_ATMEL_AIC_IRQ=y)
    sama5_defconfig (CONFIG_ATMEL_AIC5_IRQ=y)
    sunxi_defconfig (CONFIG_ARCH_SUNXI=y)

tb10x (ARC) is untested.

Signed-off-by: Kevin Cernekee 
Acked-by: Thomas Gleixner 
Acked-by: Acked-by: Arnd Bergmann 
Link: https://lkml.kernel.org/r/1415342669-30640-3-git-send-email-cernekee@gmail.com
Signed-off-by: Jason Cooper 
Signed-off-by: Sasha Levin

asm-generic: make copy_from_user() zero the destination properly

2016-10-06T02:40:20+00:00

[ Upstream commit 2545e5da080b4839dd859e3b09343a884f6ab0e3 ]

... in all cases, including the failing access_ok()

Note that some architectures using asm-generic/uaccess.h have
__copy_from_user() not zeroing the tail on failure halfway
through.  This variant works either way.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro 
Signed-off-by: Sasha Levin

PCI: Add Netronome NFP4000 PF device ID

2016-09-03T03:42:11+00:00

[ Upstream commit 69874ec233871a62e1bc8c89e643993af93a8630 ]

Add the device ID for the PF of the NFP4000.  The device ID for the VF,
0x6003, is already present as PCI_DEVICE_ID_NETRONOME_NFP6000_VF.

Signed-off-by: Simon Horman 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin