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569397 commits

Author SHA1 Message Date
Andy Lutomirski
a2e0b1c18c selftests/capabilities: Fix the test_execve test
commit 796a3bae2fba6810427efdb314a1c126c9490fb3 upstream.

test_execve does rather odd mount manipulations to safely create
temporary setuid and setgid executables that aren't visible to the
rest of the system.  Those executables end up in the test's cwd, but
that cwd is MNT_DETACHed.

The core namespace code considers MNT_DETACHed trees to belong to no
mount namespace at all and, in general, MNT_DETACHed trees are only
barely function.  This interacted with commit 380cf5ba6b0a ("fs:
Treat foreign mounts as nosuid") to cause all MNT_DETACHed trees to
act as though they're nosuid, breaking the test.

Fix it by just not detaching the tree.  It's still in a private
mount namespace and is therefore still invisible to the rest of the
system (except via /proc, and the same nosuid logic will protect all
other programs on the system from believing in test_execve's setuid
bits).

While we're at it, fix some blatant whitespace problems.

Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 380cf5ba6b0a ("fs: Treat foreign mounts as nosuid")
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Greg KH <greg@kroah.com>
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:58 +02:00
Eric W. Biederman
f07288cfb0 mnt: Make propagate_umount less slow for overlapping mount propagation trees
commit 296990deb389c7da21c78030376ba244dc1badf5 upstream.

Andrei Vagin pointed out that time to executue propagate_umount can go
non-linear (and take a ludicrious amount of time) when the mount
propogation trees of the mounts to be unmunted by a lazy unmount
overlap.

Make the walk of the mount propagation trees nearly linear by
remembering which mounts have already been visited, allowing
subsequent walks to detect when walking a mount propgation tree or a
subtree of a mount propgation tree would be duplicate work and to skip
them entirely.

Walk the list of mounts whose propgatation trees need to be traversed
from the mount highest in the mount tree to mounts lower in the mount
tree so that odds are higher that the code will walk the largest trees
first, allowing later tree walks to be skipped entirely.

Add cleanup_umount_visitation to remover the code's memory of which
mounts have been visited.

Add the functions last_slave and skip_propagation_subtree to allow
skipping appropriate parts of the mount propagation tree without
needing to change the logic of the rest of the code.

A script to generate overlapping mount propagation trees:

$ cat runs.h
set -e
mount -t tmpfs zdtm /mnt
mkdir -p /mnt/1 /mnt/2
mount -t tmpfs zdtm /mnt/1
mount --make-shared /mnt/1
mkdir /mnt/1/1

iteration=10
if [ -n "$1" ] ; then
	iteration=$1
fi

for i in $(seq $iteration); do
	mount --bind /mnt/1/1 /mnt/1/1
done

mount --rbind /mnt/1 /mnt/2

TIMEFORMAT='%Rs'
nr=$(( ( 2 ** ( $iteration + 1 ) ) + 1 ))
echo -n "umount -l /mnt/1 -> $nr        "
time umount -l /mnt/1

nr=$(cat /proc/self/mountinfo | grep zdtm | wc -l )
time umount -l /mnt/2

$ for i in $(seq 9 19); do echo $i; unshare -Urm bash ./run.sh $i; done

Here are the performance numbers with and without the patch:

     mhash |  8192   |  8192  | 1048576 | 1048576
    mounts | before  | after  |  before | after
    ------------------------------------------------
      1025 |  0.040s | 0.016s |  0.038s | 0.019s
      2049 |  0.094s | 0.017s |  0.080s | 0.018s
      4097 |  0.243s | 0.019s |  0.206s | 0.023s
      8193 |  1.202s | 0.028s |  1.562s | 0.032s
     16385 |  9.635s | 0.036s |  9.952s | 0.041s
     32769 | 60.928s | 0.063s | 44.321s | 0.064s
     65537 |         | 0.097s |         | 0.097s
    131073 |         | 0.233s |         | 0.176s
    262145 |         | 0.653s |         | 0.344s
    524289 |         | 2.305s |         | 0.735s
   1048577 |         | 7.107s |         | 2.603s

Andrei Vagin reports fixing the performance problem is part of the
work to fix CVE-2016-6213.

Fixes: a05964f391 ("[PATCH] shared mounts handling: umount")
Reported-by: Andrei Vagin <avagin@openvz.org>
Reviewed-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:58 +02:00
Eric W. Biederman
fdb8f10499 mnt: In propgate_umount handle visiting mounts in any order
commit 99b19d16471e9c3faa85cad38abc9cbbe04c6d55 upstream.

While investigating some poor umount performance I realized that in
the case of overlapping mount trees where some of the mounts are locked
the code has been failing to unmount all of the mounts it should
have been unmounting.

This failure to unmount all of the necessary
mounts can be reproduced with:

$ cat locked_mounts_test.sh

mount -t tmpfs test-base /mnt
mount --make-shared /mnt
mkdir -p /mnt/b

mount -t tmpfs test1 /mnt/b
mount --make-shared /mnt/b
mkdir -p /mnt/b/10

mount -t tmpfs test2 /mnt/b/10
mount --make-shared /mnt/b/10
mkdir -p /mnt/b/10/20

mount --rbind /mnt/b /mnt/b/10/20

unshare -Urm --propagation unchaged /bin/sh -c 'sleep 5; if [ $(grep test /proc/self/mountinfo | wc -l) -eq 1 ] ; then echo SUCCESS ; else echo FAILURE ; fi'
sleep 1
umount -l /mnt/b
wait %%

$ unshare -Urm ./locked_mounts_test.sh

This failure is corrected by removing the prepass that marks mounts
that may be umounted.

A first pass is added that umounts mounts if possible and if not sets
mount mark if they could be unmounted if they weren't locked and adds
them to a list to umount possibilities.  This first pass reconsiders
the mounts parent if it is on the list of umount possibilities, ensuring
that information of umoutability will pass from child to mount parent.

A second pass then walks through all mounts that are umounted and processes
their children unmounting them or marking them for reparenting.

A last pass cleans up the state on the mounts that could not be umounted
and if applicable reparents them to their first parent that remained
mounted.

While a bit longer than the old code this code is much more robust
as it allows information to flow up from the leaves and down
from the trunk making the order in which mounts are encountered
in the umount propgation tree irrelevant.

Fixes: 0c56fe3142 ("mnt: Don't propagate unmounts to locked mounts")
Reviewed-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Eric W. Biederman
7cbc3955ef mnt: In umount propagation reparent in a separate pass
commit 570487d3faf2a1d8a220e6ee10f472163123d7da upstream.

It was observed that in some pathlogical cases that the current code
does not unmount everything it should.  After investigation it
was determined that the issue is that mnt_change_mntpoint can
can change which mounts are available to be unmounted during mount
propagation which is wrong.

The trivial reproducer is:
$ cat ./pathological.sh

mount -t tmpfs test-base /mnt
cd /mnt
mkdir 1 2 1/1
mount --bind 1 1
mount --make-shared 1
mount --bind 1 2
mount --bind 1/1 1/1
mount --bind 1/1 1/1
echo
grep test-base /proc/self/mountinfo
umount 1/1
echo
grep test-base /proc/self/mountinfo

$ unshare -Urm ./pathological.sh

The expected output looks like:
46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000
47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
49 54 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
50 53 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
51 49 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
54 47 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
53 48 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
52 50 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000

46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000
47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000

The output without the fix looks like:
46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000
47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
49 54 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
50 53 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
51 49 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
54 47 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
53 48 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
52 50 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000

46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000
47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000
52 48 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000

That last mount in the output was in the propgation tree to be unmounted but
was missed because the mnt_change_mountpoint changed it's parent before the walk
through the mount propagation tree observed it.

Fixes: 1064f874abc0 ("mnt: Tuck mounts under others instead of creating shadow/side mounts.")
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Reviewed-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Adam Borowski
050b074e22 vt: fix unchecked __put_user() in tioclinux ioctls
commit 6987dc8a70976561d22450b5858fc9767788cc1c upstream.

Only read access is checked before this call.

Actually, at the moment this is not an issue, as every in-tree arch does
the same manual checks for VERIFY_READ vs VERIFY_WRITE, relying on the MMU
to tell them apart, but this wasn't the case in the past and may happen
again on some odd arch in the future.

If anyone cares about 3.7 and earlier, this is a security hole (untested)
on real 80386 CPUs.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Kees Cook
86949eb964 exec: Limit arg stack to at most 75% of _STK_LIM
commit da029c11e6b12f321f36dac8771e833b65cec962 upstream.

To avoid pathological stack usage or the need to special-case setuid
execs, just limit all arg stack usage to at most 75% of _STK_LIM (6MB).

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Kees Cook
7888c0296c s390: reduce ELF_ET_DYN_BASE
commit a73dc5370e153ac63718d850bddf0c9aa9d871e6 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, which is the
traditional x86 minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).  For s390 the
position could be 0x10000, but that is needlessly close to the NULL
address.

Link: http://lkml.kernel.org/r/1498154792-49952-5-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Kees Cook
72a333a046 powerpc: move ELF_ET_DYN_BASE to 4GB / 4MB
commit 47ebb09d54856500c5a5e14824781902b3bb738e upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, which is the
traditional x86 minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).

Link: http://lkml.kernel.org/r/1498154792-49952-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Kees Cook
43cf90f788 arm64: move ELF_ET_DYN_BASE to 4GB / 4MB
commit 02445990a96e60a67526510d8b00f7e3d14101c3 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, to match ARM.
This could be 0x8000, the standard ET_EXEC load address, but that is
needlessly close to the NULL address, and anyone running arm compat PIE
will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498251600-132458-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Kees Cook
d2471b5e84 arm: move ELF_ET_DYN_BASE to 4MB
commit 6a9af90a3bcde217a1c053e135f5f43e5d5fafbd upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

4MB is chosen here mainly to have parity with x86, where this is the
traditional minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).

For ARM the position could be 0x8000, the standard ET_EXEC load address,
but that is needlessly close to the NULL address, and anyone running PIE
on 32-bit ARM will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498154792-49952-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Qualys Security Advisory <qsa@qualys.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Kees Cook
7eb968cd04 binfmt_elf: use ELF_ET_DYN_BASE only for PIE
commit eab09532d40090698b05a07c1c87f39fdbc5fab5 upstream.

The ELF_ET_DYN_BASE position was originally intended to keep loaders
away from ET_EXEC binaries.  (For example, running "/lib/ld-linux.so.2
/bin/cat" might cause the subsequent load of /bin/cat into where the
loader had been loaded.)

With the advent of PIE (ET_DYN binaries with an INTERP Program Header),
ELF_ET_DYN_BASE continued to be used since the kernel was only looking
at ET_DYN.  However, since ELF_ET_DYN_BASE is traditionally set at the
top 1/3rd of the TASK_SIZE, a substantial portion of the address space
is unused.

For 32-bit tasks when RLIMIT_STACK is set to RLIM_INFINITY, programs are
loaded above the mmap region.  This means they can be made to collide
(CVE-2017-1000370) or nearly collide (CVE-2017-1000371) with
pathological stack regions.

Lowering ELF_ET_DYN_BASE solves both by moving programs below the mmap
region in all cases, and will now additionally avoid programs falling
back to the mmap region by enforcing MAP_FIXED for program loads (i.e.
if it would have collided with the stack, now it will fail to load
instead of falling back to the mmap region).

To allow for a lower ELF_ET_DYN_BASE, loaders (ET_DYN without INTERP)
are loaded into the mmap region, leaving space available for either an
ET_EXEC binary with a fixed location or PIE being loaded into mmap by
the loader.  Only PIE programs are loaded offset from ELF_ET_DYN_BASE,
which means architectures can now safely lower their values without risk
of loaders colliding with their subsequently loaded programs.

For 64-bit, ELF_ET_DYN_BASE is best set to 4GB to allow runtimes to use
the entire 32-bit address space for 32-bit pointers.

Thanks to PaX Team, Daniel Micay, and Rik van Riel for inspiration and
suggestions on how to implement this solution.

Fixes: d1fd836dcf ("mm: split ET_DYN ASLR from mmap ASLR")
Link: http://lkml.kernel.org/r/20170621173201.GA114489@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Qualys Security Advisory <qsa@qualys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Cyril Bur
4544e9ebef checkpatch: silence perl 5.26.0 unescaped left brace warnings
commit 8d81ae05d0176da1c54aeaed697fa34be5c5575e upstream.

As of perl 5, version 26, subversion 0 (v5.26.0) some new warnings have
occurred when running checkpatch.

Unescaped left brace in regex is deprecated here (and will be fatal in
Perl 5.30), passed through in regex; marked by <-- HERE in m/^(.\s*){
<-- HERE \s*/ at scripts/checkpatch.pl line 3544.

Unescaped left brace in regex is deprecated here (and will be fatal in
Perl 5.30), passed through in regex; marked by <-- HERE in m/^(.\s*){
<-- HERE \s*/ at scripts/checkpatch.pl line 3885.

Unescaped left brace in regex is deprecated here (and will be fatal in
Perl 5.30), passed through in regex; marked by <-- HERE in
m/^(\+.*(?:do|\))){ <-- HERE / at scripts/checkpatch.pl line 4374.

It seems perfectly reasonable to do as the warning suggests and simply
escape the left brace in these three locations.

Link: http://lkml.kernel.org/r/20170607060135.17384-1-cyrilbur@gmail.com
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Sahitya Tummala
68b0f5d85b fs/dcache.c: fix spin lockup issue on nlru->lock
commit b17c070fb624cf10162cf92ea5e1ec25cd8ac176 upstream.

__list_lru_walk_one() acquires nlru spin lock (nlru->lock) for longer
duration if there are more number of items in the lru list.  As per the
current code, it can hold the spin lock for upto maximum UINT_MAX
entries at a time.  So if there are more number of items in the lru
list, then "BUG: spinlock lockup suspected" is observed in the below
path:

  spin_bug+0x90
  do_raw_spin_lock+0xfc
  _raw_spin_lock+0x28
  list_lru_add+0x28
  dput+0x1c8
  path_put+0x20
  terminate_walk+0x3c
  path_lookupat+0x100
  filename_lookup+0x6c
  user_path_at_empty+0x54
  SyS_faccessat+0xd0
  el0_svc_naked+0x24

This nlru->lock is acquired by another CPU in this path -

  d_lru_shrink_move+0x34
  dentry_lru_isolate_shrink+0x48
  __list_lru_walk_one.isra.10+0x94
  list_lru_walk_node+0x40
  shrink_dcache_sb+0x60
  do_remount_sb+0xbc
  do_emergency_remount+0xb0
  process_one_work+0x228
  worker_thread+0x2e0
  kthread+0xf4
  ret_from_fork+0x10

Fix this lockup by reducing the number of entries to be shrinked from
the lru list to 1024 at once.  Also, add cond_resched() before
processing the lru list again.

Link: http://marc.info/?t=149722864900001&r=1&w=2
Link: http://lkml.kernel.org/r/1498707575-2472-1-git-send-email-stummala@codeaurora.org
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Suggested-by: Jan Kara <jack@suse.cz>
Suggested-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Alexander Polakov <apolyakov@beget.ru>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Sahitya Tummala
2d0db02d2e mm/list_lru.c: fix list_lru_count_node() to be race free
commit 2c80cd57c74339889a8752b20862a16c28929c3a upstream.

list_lru_count_node() iterates over all memcgs to get the total number of
entries on the node but it can race with memcg_drain_all_list_lrus(),
which migrates the entries from a dead cgroup to another.  This can return
incorrect number of entries from list_lru_count_node().

Fix this by keeping track of entries per node and simply return it in
list_lru_count_node().

Link: http://lkml.kernel.org/r/1498707555-30525-1-git-send-email-stummala@codeaurora.org
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Alexander Polakov <apolyakov@beget.ru>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Marcin Nowakowski
717ce69e47 kernel/extable.c: mark core_kernel_text notrace
commit c0d80ddab89916273cb97114889d3f337bc370ae upstream.

core_kernel_text is used by MIPS in its function graph trace processing,
so having this method traced leads to an infinite set of recursive calls
such as:

  Call Trace:
     ftrace_return_to_handler+0x50/0x128
     core_kernel_text+0x10/0x1b8
     prepare_ftrace_return+0x6c/0x114
     ftrace_graph_caller+0x20/0x44
     return_to_handler+0x10/0x30
     return_to_handler+0x0/0x30
     return_to_handler+0x0/0x30
     ftrace_ops_no_ops+0x114/0x1bc
     core_kernel_text+0x10/0x1b8
     core_kernel_text+0x10/0x1b8
     core_kernel_text+0x10/0x1b8
     ftrace_ops_no_ops+0x114/0x1bc
     core_kernel_text+0x10/0x1b8
     prepare_ftrace_return+0x6c/0x114
     ftrace_graph_caller+0x20/0x44
     (...)

Mark the function notrace to avoid it being traced.

Link: http://lkml.kernel.org/r/1498028607-6765-1-git-send-email-marcin.nowakowski@imgtec.com
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Meyer <thomas@m3y3r.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Ben Hutchings
0d6ee0bea8 tools/lib/lockdep: Reduce MAX_LOCK_DEPTH to avoid overflowing lock_chain/: Depth
commit 98dcea0cfd04e083ac74137ceb9a632604740e2d upstream.

liblockdep has been broken since commit 75dd602a5198 ("lockdep: Fix
lock_chain::base size"), as that adds a check that MAX_LOCK_DEPTH is
within the range of lock_chain::depth and in liblockdep it is much
too large.

That should have resulted in a compiler error, but didn't because:

- the check uses ARRAY_SIZE(), which isn't yet defined in liblockdep
  so is assumed to be an (undeclared) function
- putting a function call inside a BUILD_BUG_ON() expression quietly
  turns it into some nonsense involving a variable-length array

It did produce a compiler warning, but I didn't notice because
liblockdep already produces too many warnings if -Wall is enabled
(which I'll fix shortly).

Even before that commit, which reduced lock_chain::depth from 8 bits
to 6, MAX_LOCK_DEPTH was too large.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/20170525130005.5947-3-alexander.levin@verizon.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Helge Deller
b291457465 parisc/mm: Ensure IRQs are off in switch_mm()
commit 649aa24254e85bf6bd7807dd372d083707852b1f upstream.

This is because of commit f98db6013c55 ("sched/core: Add switch_mm_irqs_off()
and use it in the scheduler") in which switch_mm_irqs_off() is called by the
scheduler, vs switch_mm() which is used by use_mm().

This patch lets the parisc code mirror the x86 and powerpc code, ie. it
disables interrupts in switch_mm(), and optimises the scheduler case by
defining switch_mm_irqs_off().

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Thomas Bogendoerfer
635a58225c parisc: DMA API: return error instead of BUG_ON for dma ops on non dma devs
commit 33f9e02495d15a061f0c94ef46f5103a2d0c20f3 upstream.

Enabling parport pc driver on a B2600 (and probably other 64bit PARISC
systems) produced following BUG:

CPU: 0 PID: 1 Comm: swapper Not tainted 4.12.0-rc5-30198-g1132d5e #156
task: 000000009e050000 task.stack: 000000009e04c000

     YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001101111111100001111 Not tainted
r00-03  000000ff0806ff0f 000000009e04c990 0000000040871b78 000000009e04cac0
r04-07  0000000040c14de0 ffffffffffffffff 000000009e07f098 000000009d82d200
r08-11  000000009d82d210 0000000000000378 0000000000000000 0000000040c345e0
r12-15  0000000000000005 0000000040c345e0 0000000000000000 0000000040c9d5e0
r16-19  0000000040c345e0 00000000f00001c4 00000000f00001bc 0000000000000061
r20-23  000000009e04ce28 0000000000000010 0000000000000010 0000000040b89e40
r24-27  0000000000000003 0000000000ffffff 000000009d82d210 0000000040c14de0
r28-31  0000000000000000 000000009e04ca90 000000009e04cb40 0000000000000000
sr00-03  0000000000000000 0000000000000000 0000000000000000 0000000000000000
sr04-07  0000000000000000 0000000000000000 0000000000000000 0000000000000000

IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000404aece0 00000000404aece4
 IIR: 03ffe01f    ISR: 0000000010340000  IOR: 000001781304cac8
 CPU:        0   CR30: 000000009e04c000 CR31: 00000000e2976de2
 ORIG_R28: 0000000000000200
 IAOQ[0]: sba_dma_supported+0x80/0xd0
 IAOQ[1]: sba_dma_supported+0x84/0xd0
 RP(r2): parport_pc_probe_port+0x178/0x1200

Cause is a call to dma_coerce_mask_and_coherenet in parport_pc_probe_port,
which PARISC DMA API doesn't handle very nicely. This commit gives back
DMA_ERROR_CODE for DMA API calls, if device isn't capable of DMA
transaction.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Eric Biggers
f265641dc8 parisc: use compat_sys_keyctl()
commit b0f94efd5aa8daa8a07d7601714c2573266cd4c9 upstream.

Architectures with a compat syscall table must put compat_sys_keyctl()
in it, not sys_keyctl().  The parisc architecture was not doing this;
fix it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Helge Deller
e18ca17b90 parisc: Report SIGSEGV instead of SIGBUS when running out of stack
commit 247462316f85a9e0479445c1a4223950b68ffac1 upstream.

When a process runs out of stack the parisc kernel wrongly faults with SIGBUS
instead of the expected SIGSEGV signal.

This example shows how the kernel faults:
do_page_fault() command='a.out' type=15 address=0xfaac2000 in libc-2.24.so[f8308000+16c000]
trap #15: Data TLB miss fault, vm_start = 0xfa2c2000, vm_end = 0xfaac2000

The vma->vm_end value is the first address which does not belong to the vma, so
adjust the check to include vma->vm_end to the range for which to send the
SIGSEGV signal.

This patch unbreaks building the debian libsigsegv package.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Suzuki K Poulose
970616464f irqchip/gic-v3: Fix out-of-bound access in gic_set_affinity
commit 866d7c1b0a3c70387646c4e455e727a58c5d465a upstream.

The GICv3 driver doesn't check if the target CPU for gic_set_affinity
is valid before going ahead and making the changes. This triggers the
following splat with KASAN:

[  141.189434] BUG: KASAN: global-out-of-bounds in gic_set_affinity+0x8c/0x140
[  141.189704] Read of size 8 at addr ffff200009741d20 by task swapper/1/0
[  141.189958]
[  141.190158] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.12.0-rc7
[  141.190458] Hardware name: Foundation-v8A (DT)
[  141.190658] Call trace:
[  141.190908] [<ffff200008089d70>] dump_backtrace+0x0/0x328
[  141.191224] [<ffff20000808a1b4>] show_stack+0x14/0x20
[  141.191507] [<ffff200008504c3c>] dump_stack+0xa4/0xc8
[  141.191858] [<ffff20000826c19c>] print_address_description+0x13c/0x250
[  141.192219] [<ffff20000826c5c8>] kasan_report+0x210/0x300
[  141.192547] [<ffff20000826ad54>] __asan_load8+0x84/0x98
[  141.192874] [<ffff20000854eeec>] gic_set_affinity+0x8c/0x140
[  141.193158] [<ffff200008148b14>] irq_do_set_affinity+0x54/0xb8
[  141.193473] [<ffff200008148d2c>] irq_set_affinity_locked+0x64/0xf0
[  141.193828] [<ffff200008148e00>] __irq_set_affinity+0x48/0x78
[  141.194158] [<ffff200008bc48a4>] arm_perf_starting_cpu+0x104/0x150
[  141.194513] [<ffff2000080d73bc>] cpuhp_invoke_callback+0x17c/0x1f8
[  141.194783] [<ffff2000080d94ec>] notify_cpu_starting+0x8c/0xb8
[  141.195130] [<ffff2000080911ec>] secondary_start_kernel+0x15c/0x200
[  141.195390] [<0000000080db81b4>] 0x80db81b4
[  141.195603]
[  141.195685] The buggy address belongs to the variable:
[  141.196012]  __cpu_logical_map+0x200/0x220
[  141.196176]
[  141.196315] Memory state around the buggy address:
[  141.196586]  ffff200009741c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  141.196913]  ffff200009741c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  141.197158] >ffff200009741d00: 00 00 00 00 fa fa fa fa 00 00 00 00 00 00 00 00
[  141.197487]                                ^
[  141.197758]  ffff200009741d80: 00 00 00 00 00 00 00 00 fa fa fa fa 00 00 00 00
[  141.198060]  ffff200009741e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  141.198358] ==================================================================
[  141.198609] Disabling lock debugging due to kernel taint
[  141.198961] CPU1: Booted secondary processor [410fd051]

This patch adds the check to make sure the cpu is valid.

Fixes: commit 021f653791 ("irqchip: gic-v3: Initial support for GICv3")
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Srinivas Dasari
2d3c10e215 cfg80211: Check if PMKID attribute is of expected size
commit 9361df14d1cbf966409d5d6f48bb334384fbe138 upstream.

nla policy checks for only maximum length of the attribute data
when the attribute type is NLA_BINARY. If userspace sends less
data than specified, the wireless drivers may access illegal
memory. When type is NLA_UNSPEC, nla policy check ensures that
userspace sends minimum specified length number of bytes.

Remove type assignment to NLA_BINARY from nla_policy of
NL80211_ATTR_PMKID to make this NLA_UNSPEC and to make sure minimum
WLAN_PMKID_LEN bytes are received from userspace with
NL80211_ATTR_PMKID.

Fixes: 67fbb16be6 ("nl80211: PMKSA caching support")
Signed-off-by: Srinivas Dasari <dasaris@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:56 +02:00
Srinivas Dasari
24d0410712 cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES
commit d7f13f7450369281a5d0ea463cc69890a15923ae upstream.

validate_scan_freqs() retrieves frequencies from attributes
nested in the attribute NL80211_ATTR_SCAN_FREQUENCIES with
nla_get_u32(), which reads 4 bytes from each attribute
without validating the size of data received. Attributes
nested in NL80211_ATTR_SCAN_FREQUENCIES don't have an nla policy.

Validate size of each attribute before parsing to avoid potential buffer
overread.

Fixes: 2a51931192 ("cfg80211/nl80211: scanning (and mac80211 update to use it)")
Signed-off-by: Srinivas Dasari <dasaris@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Srinivas Dasari
05bf0b6ef9 cfg80211: Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE
commit 8feb69c7bd89513be80eb19198d48f154b254021 upstream.

Buffer overread may happen as nl80211_set_station() reads 4 bytes
from the attribute NL80211_ATTR_LOCAL_MESH_POWER_MODE without
validating the size of data received when userspace sends less
than 4 bytes of data with NL80211_ATTR_LOCAL_MESH_POWER_MODE.
Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE to avoid
the buffer overread.

Fixes: 3b1c5a5307 ("{cfg,nl}80211: mesh power mode primitives and userspace access")
Signed-off-by: Srinivas Dasari <dasaris@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Arend van Spriel
4c7021c2fb brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()
commit 8f44c9a41386729fea410e688959ddaa9d51be7c upstream.

The lower level nl80211 code in cfg80211 ensures that "len" is between
25 and NL80211_ATTR_FRAME (2304).  We subtract DOT11_MGMT_HDR_LEN (24) from
"len" so thats's max of 2280.  However, the action_frame->data[] buffer is
only BRCMF_FIL_ACTION_FRAME_SIZE (1800) bytes long so this memcpy() can
overflow.

	memcpy(action_frame->data, &buf[DOT11_MGMT_HDR_LEN],
	       le16_to_cpu(action_frame->len));

Fixes: 18e2f61db3 ("brcmfmac: P2P action frame tx.")
Reported-by: "freenerguo(郭大兴)" <freenerguo@tencent.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Sowmini Varadhan
9618eb4af3 rds: tcp: use sock_create_lite() to create the accept socket
commit 0933a578cd55b02dc80f219dc8f2efb17ec61c9a upstream.

There are two problems with calling sock_create_kern() from
rds_tcp_accept_one()
1. it sets up a new_sock->sk that is wasteful, because this ->sk
   is going to get replaced by inet_accept() in the subsequent ->accept()
2. The new_sock->sk is a leaked reference in sock_graft() which
   expects to find a null parent->sk

Avoid these problems by calling sock_create_lite().

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Nikolay Aleksandrov
89e7f17f8f vrf: fix bug_on triggered by rx when destroying a vrf
commit f630c38ef0d785101363a8992bbd4f302180f86f upstream.

When destroying a VRF device we cleanup the slaves in its ndo_uninit()
function, but that causes packets to be switched (skb->dev == vrf being
destroyed) even though we're pass the point where the VRF should be
receiving any packets while it is being dismantled. This causes a BUG_ON
to trigger if we have raw sockets (trace below).
The reason is that the inetdev of the VRF has been destroyed but we're
still sending packets up the stack with it, so let's free the slaves in
the dellink callback as David Ahern suggested.

Note that this fix doesn't prevent packets from going up when the VRF
device is admin down.

[   35.631371] ------------[ cut here ]------------
[   35.631603] kernel BUG at net/ipv4/fib_frontend.c:285!
[   35.631854] invalid opcode: 0000 [#1] SMP
[   35.631977] Modules linked in:
[   35.632081] CPU: 2 PID: 22 Comm: ksoftirqd/2 Not tainted 4.12.0-rc7+ #45
[   35.632247] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[   35.632477] task: ffff88005ad68000 task.stack: ffff88005ad64000
[   35.632632] RIP: 0010:fib_compute_spec_dst+0xfc/0x1ee
[   35.632769] RSP: 0018:ffff88005ad67978 EFLAGS: 00010202
[   35.632910] RAX: 0000000000000001 RBX: ffff880059a7f200 RCX: 0000000000000000
[   35.633084] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff82274af0
[   35.633256] RBP: ffff88005ad679f8 R08: 000000000001ef70 R09: 0000000000000046
[   35.633430] R10: ffff88005ad679f8 R11: ffff880037731cb0 R12: 0000000000000001
[   35.633603] R13: ffff8800599e3000 R14: 0000000000000000 R15: ffff8800599cb852
[   35.634114] FS:  0000000000000000(0000) GS:ffff88005d900000(0000) knlGS:0000000000000000
[   35.634306] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   35.634456] CR2: 00007f3563227095 CR3: 000000000201d000 CR4: 00000000000406e0
[   35.634632] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   35.634865] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   35.635055] Call Trace:
[   35.635271]  ? __lock_acquire+0xf0d/0x1117
[   35.635522]  ipv4_pktinfo_prepare+0x82/0x151
[   35.635831]  raw_rcv_skb+0x17/0x3c
[   35.636062]  raw_rcv+0xe5/0xf7
[   35.636287]  raw_local_deliver+0x169/0x1d9
[   35.636534]  ip_local_deliver_finish+0x87/0x1c4
[   35.636820]  ip_local_deliver+0x63/0x7f
[   35.637058]  ip_rcv_finish+0x340/0x3a1
[   35.637295]  ip_rcv+0x314/0x34a
[   35.637525]  __netif_receive_skb_core+0x49f/0x7c5
[   35.637780]  ? lock_acquire+0x13f/0x1d7
[   35.638018]  ? lock_acquire+0x15e/0x1d7
[   35.638259]  __netif_receive_skb+0x1e/0x94
[   35.638502]  ? __netif_receive_skb+0x1e/0x94
[   35.638748]  netif_receive_skb_internal+0x74/0x300
[   35.639002]  ? dev_gro_receive+0x2ed/0x411
[   35.639246]  ? lock_is_held_type+0xc4/0xd2
[   35.639491]  napi_gro_receive+0x105/0x1a0
[   35.639736]  receive_buf+0xc32/0xc74
[   35.639965]  ? detach_buf+0x67/0x153
[   35.640201]  ? virtqueue_get_buf_ctx+0x120/0x176
[   35.640453]  virtnet_poll+0x128/0x1c5
[   35.640690]  net_rx_action+0x103/0x343
[   35.640932]  __do_softirq+0x1c7/0x4b7
[   35.641171]  run_ksoftirqd+0x23/0x5c
[   35.641403]  smpboot_thread_fn+0x24f/0x26d
[   35.641646]  ? sort_range+0x22/0x22
[   35.641878]  kthread+0x129/0x131
[   35.642104]  ? __list_add+0x31/0x31
[   35.642335]  ? __list_add+0x31/0x31
[   35.642568]  ret_from_fork+0x2a/0x40
[   35.642804] Code: 05 bd 87 a3 00 01 e8 1f ef 98 ff 4d 85 f6 48 c7 c7 f0 4a 27 82 41 0f 94 c4 31 c9 31 d2 41 0f b6 f4 e8 04 71 a1 ff 45 84 e4 74 02 <0f> 0b 0f b7 93 c4 00 00 00 4d 8b a5 80 05 00 00 48 03 93 d0 00
[   35.644342] RIP: fib_compute_spec_dst+0xfc/0x1ee RSP: ffff88005ad67978

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Reported-by: Chris Cormier <chriscormier@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[backport to 4.4 - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
David Ahern
eb7bef1db6 net: ipv6: Compare lwstate in detecting duplicate nexthops
commit f06b7549b79e29a672336d4e134524373fb7a232 upstream.

Lennert reported a failure to add different mpls encaps in a multipath
route:

  $ ip -6 route add 1234::/16 \
        nexthop encap mpls 10 via fe80::1 dev ens3 \
        nexthop encap mpls 20 via fe80::1 dev ens3
  RTNETLINK answers: File exists

The problem is that the duplicate nexthop detection does not compare
lwtunnel configuration. Add it.

Fixes: 19e42e4515 ("ipv6: support for fib route lwtunnel encap attributes")
Signed-off-by: David Ahern <dsahern@gmail.com>
Reported-by: João Taveira Araújo <joao.taveira@gmail.com>
Reported-by: Lennert Buytenhek <buytenh@wantstofly.org>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Tested-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Sabrina Dubroca
0c32b01ee4 ipv6: dad: don't remove dynamic addresses if link is down
commit ec8add2a4c9df723c94a863b8fcd6d93c472deed upstream.

Currently, when the link for $DEV is down, this command succeeds but the
address is removed immediately by DAD (1):

    ip addr add 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800

In the same situation, this will succeed and not remove the address (2):

    ip addr add 1111::12/64 dev $DEV
    ip addr change 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800

The comment in addrconf_dad_begin() when !IF_READY makes it look like
this is the intended behavior, but doesn't explain why:

     * If the device is not ready:
     * - keep it tentative if it is a permanent address.
     * - otherwise, kill it.

We clearly cannot prevent userspace from doing (2), but we can make (1)
work consistently with (2).

addrconf_dad_stop() is only called in two cases: if DAD failed, or to
skip DAD when the link is down. In that second case, the fix is to avoid
deleting the address, like we already do for permanent addresses.

Fixes: 3c21edbd11 ("[IPV6]: Defer IPv6 device initialization until the link becomes ready.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Michal Kubeček
38ae32c9f1 net: handle NAPI_GRO_FREE_STOLEN_HEAD case also in napi_frags_finish()
commit e44699d2c28067f69698ccb68dd3ddeacfebc434 upstream.

Recently I started seeing warnings about pages with refcount -1. The
problem was traced to packets being reused after their head was merged into
a GRO packet by skb_gro_receive(). While bisecting the issue pointed to
commit c21b48cc1bbf ("net: adjust skb->truesize in ___pskb_trim()") and
I have never seen it on a kernel with it reverted, I believe the real
problem appeared earlier when the option to merge head frag in GRO was
implemented.

Handling NAPI_GRO_FREE_STOLEN_HEAD state was only added to GRO_MERGED_FREE
branch of napi_skb_finish() so that if the driver uses napi_gro_frags()
and head is merged (which in my case happens after the skb_condense()
call added by the commit mentioned above), the skb is reused including the
head that has been merged. As a result, we release the page reference
twice and eventually end up with negative page refcount.

To fix the problem, handle NAPI_GRO_FREE_STOLEN_HEAD in napi_frags_finish()
the same way it's done in napi_skb_finish().

Fixes: d7e8883cfc ("net: make GRO aware of skb->head_frag")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Daniel Borkmann
1a4f13e0a9 bpf: prevent leaking pointer via xadd on unpriviledged
commit 6bdf6abc56b53103324dfd270a86580306e1a232 upstream.

Leaking kernel addresses on unpriviledged is generally disallowed,
for example, verifier rejects the following:

  0: (b7) r0 = 0
  1: (18) r2 = 0xffff897e82304400
  3: (7b) *(u64 *)(r1 +48) = r2
  R2 leaks addr into ctx

Doing pointer arithmetic on them is also forbidden, so that they
don't turn into unknown value and then get leaked out. However,
there's xadd as a special case, where we don't check the src reg
for being a pointer register, e.g. the following will pass:

  0: (b7) r0 = 0
  1: (7b) *(u64 *)(r1 +48) = r0
  2: (18) r2 = 0xffff897e82304400 ; map
  4: (db) lock *(u64 *)(r1 +48) += r2
  5: (95) exit

We could store the pointer into skb->cb, loose the type context,
and then read it out from there again to leak it eventually out
of a map value. Or more easily in a different variant, too:

   0: (bf) r6 = r1
   1: (7a) *(u64 *)(r10 -8) = 0
   2: (bf) r2 = r10
   3: (07) r2 += -8
   4: (18) r1 = 0x0
   6: (85) call bpf_map_lookup_elem#1
   7: (15) if r0 == 0x0 goto pc+3
   R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R6=ctx R10=fp
   8: (b7) r3 = 0
   9: (7b) *(u64 *)(r0 +0) = r3
  10: (db) lock *(u64 *)(r0 +0) += r6
  11: (b7) r0 = 0
  12: (95) exit

  from 7 to 11: R0=inv,min_value=0,max_value=0 R6=ctx R10=fp
  11: (b7) r0 = 0
  12: (95) exit

Prevent this by checking xadd src reg for pointer types. Also
add a couple of test cases related to this.

Fixes: 1be7f75d16 ("bpf: enable non-root eBPF programs")
Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:55 +02:00
Eric Dumazet
d598f7ff24 net: prevent sign extension in dev_get_stats()
commit 6f64ec74515925cced6df4571638b5a099a49aae upstream.

Similar to the fix provided by Dominik Heidler in commit
9b3dc0a17d73 ("l2tp: cast l2tp traffic counter to unsigned")
we need to take care of 32bit kernels in dev_get_stats().

When using atomic_long_read(), we add a 'long' to u64 and
might misinterpret high order bit, unless we cast to unsigned.

Fixes: caf586e5f2 ("net: add a core netdev->rx_dropped counter")
Fixes: 015f0688f5 ("net: net: add a core netdev->tx_dropped counter")
Fixes: 6e7333d315a76 ("net: add rx_nohandler stat counter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
WANG Cong
32a44f1ba7 tcp: reset sk_rx_dst in tcp_disconnect()
commit d747a7a51b00984127a88113cdbbc26f91e9d815 upstream.

We have to reset the sk->sk_rx_dst when we disconnect a TCP
connection, because otherwise when we re-connect it this
dst reference is simply overridden in tcp_finish_connect().

This fixes a dst leak which leads to a loopback dev refcnt
leak. It is a long-standing bug, Kevin reported a very similar
(if not same) bug before. Thanks to Andrei for providing such
a reliable reproducer which greatly narrows down the problem.

Fixes: 41063e9dd1 ("ipv4: Early TCP socket demux.")
Reported-by: Andrei Vagin <avagin@gmail.com>
Reported-by: Kevin Xu <kaiwen.xu@hulu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
Richard Cochran
ccff2f4afb net: dp83640: Avoid NULL pointer dereference.
commit db9d8b29d19d2801793e4419f4c6272bf8951c62 upstream.

The function, skb_complete_tx_timestamp(), used to allow passing in a
NULL pointer for the time stamps, but that was changed in commit
62bccb8cdb ("net-timestamp: Make the
clone operation stand-alone from phy timestamping"), and the existing
call sites, all of which are in the dp83640 driver, were fixed up.

Even though the kernel-doc was subsequently updated in commit
7a76a021cd ("net-timestamp: Update
skb_complete_tx_timestamp comment"), still a bug fix from Manfred
Rudigier came into the driver using the old semantics.  Probably
Manfred derived that patch from an older kernel version.

This fix should be applied to the stable trees as well.

Fixes: 81e8f2e930fe ("net: dp83640: Fix tx timestamp overflow handling.")
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
WANG Cong
6a87cca39f ipv6: avoid unregistering inet6_dev for loopback
commit 60abc0be96e00ca71bac083215ac91ad2e575096 upstream.

The per netns loopback_dev->ip6_ptr is unregistered and set to
NULL when its mtu is set to smaller than IPV6_MIN_MTU, this
leads to that we could set rt->rt6i_idev NULL after a
rt6_uncached_list_flush_dev() and then crash after another
call.

In this case we should just bring its inet6_dev down, rather
than unregistering it, at least prior to commit 176c39af29
("netns: fix addrconf_ifdown kernel panic") we always
override the case for loopback.

Thanks a lot to Andrey for finding a reliable reproducer.

Fixes: 176c39af29 ("netns: fix addrconf_ifdown kernel panic")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
Zach Brown
f71e514024 net/phy: micrel: configure intterupts after autoneg workaround
commit b866203d872d5deeafcecd25ea429d6748b5bd56 upstream.

The commit ("net/phy: micrel: Add workaround for bad autoneg") fixes an
autoneg failure case by resetting the hardware. This turns off
intterupts. Things will work themselves out if the phy polls, as it will
figure out it's state during a poll. However if the phy uses only
intterupts, the phy will stall, since interrupts are off. This patch
fixes the issue by calling config_intr after resetting the phy.

Fixes: d2fd719bcb ("net/phy: micrel: Add workaround for bad autoneg ")
Signed-off-by: Zach Brown <zach.brown@ni.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
Gao Feng
c485792ed6 net: sched: Fix one possible panic when no destroy callback
commit c1a4872ebfb83b1af7144f7b29ac8c4b344a12a8 upstream.

When qdisc fail to init, qdisc_create would invoke the destroy callback
to cleanup. But there is no check if the callback exists really. So it
would cause the panic if there is no real destroy callback like the qdisc
codel, fq, and so on.

Take codel as an example following:
When a malicious user constructs one invalid netlink msg, it would cause
codel_init->codel_change->nla_parse_nested failed.
Then kernel would invoke the destroy callback directly but qdisc codel
doesn't define one. It causes one panic as a result.

Now add one the check for destroy to avoid the possible panic.

Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
Eric Dumazet
0be4c96e7c net_sched: fix error recovery at qdisc creation
commit 87b60cfacf9f17cf71933c6e33b66e68160af71d upstream.

Dmitry reported uses after free in qdisc code [1]

The problem here is that ops->init() can return an error.

qdisc_create_dflt() then call ops->destroy(),
while qdisc_create() does _not_ call it.

Four qdisc chose to call their own ops->destroy(), assuming their caller
would not.

This patch makes sure qdisc_create() calls ops->destroy()
and fixes the four qdisc to avoid double free.

[1]
BUG: KASAN: use-after-free in mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 at addr ffff8801d415d440
Read of size 8 by task syz-executor2/5030
CPU: 0 PID: 5030 Comm: syz-executor2 Not tainted 4.3.5-smp-DEV #119
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000046 ffff8801b435b870 ffffffff81bbbed4 ffff8801db000400
 ffff8801d415d440 ffff8801d415dc40 ffff8801c4988510 ffff8801b435b898
 ffffffff816682b1 ffff8801b435b928 ffff8801d415d440 ffff8801c49880c0
Call Trace:
 [<ffffffff81bbbed4>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81bbbed4>] dump_stack+0x6c/0x98 lib/dump_stack.c:51
 [<ffffffff816682b1>] kasan_object_err+0x21/0x70 mm/kasan/report.c:158
 [<ffffffff81668524>] print_address_description mm/kasan/report.c:196 [inline]
 [<ffffffff81668524>] kasan_report_error+0x1b4/0x4b0 mm/kasan/report.c:285
 [<ffffffff81668953>] kasan_report mm/kasan/report.c:305 [inline]
 [<ffffffff81668953>] __asan_report_load8_noabort+0x43/0x50 mm/kasan/report.c:326
 [<ffffffff82527b02>] mq_destroy+0x242/0x290 net/sched/sch_mq.c:33
 [<ffffffff82524bdd>] qdisc_destroy+0x12d/0x290 net/sched/sch_generic.c:953
 [<ffffffff82524e30>] qdisc_create_dflt+0xf0/0x120 net/sched/sch_generic.c:848
 [<ffffffff8252550d>] attach_default_qdiscs net/sched/sch_generic.c:1029 [inline]
 [<ffffffff8252550d>] dev_activate+0x6ad/0x880 net/sched/sch_generic.c:1064
 [<ffffffff824b1db1>] __dev_open+0x221/0x320 net/core/dev.c:1403
 [<ffffffff824b24ce>] __dev_change_flags+0x15e/0x3e0 net/core/dev.c:6858
 [<ffffffff824b27de>] dev_change_flags+0x8e/0x140 net/core/dev.c:6926
 [<ffffffff824f5bf6>] dev_ifsioc+0x446/0x890 net/core/dev_ioctl.c:260
 [<ffffffff824f61fa>] dev_ioctl+0x1ba/0xb80 net/core/dev_ioctl.c:546
 [<ffffffff82430509>] sock_do_ioctl+0x99/0xb0 net/socket.c:879
 [<ffffffff82430d30>] sock_ioctl+0x2a0/0x390 net/socket.c:958
 [<ffffffff816f3b68>] vfs_ioctl fs/ioctl.c:44 [inline]
 [<ffffffff816f3b68>] do_vfs_ioctl+0x8a8/0xe50 fs/ioctl.c:611
 [<ffffffff816f41a4>] SYSC_ioctl fs/ioctl.c:626 [inline]
 [<ffffffff816f41a4>] SyS_ioctl+0x94/0xc0 fs/ioctl.c:617
 [<ffffffff8123e357>] entry_SYSCALL_64_fastpath+0x12/0x17

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:54 +02:00
Badhri Jagan Sridharan
492a6047e7 ANDROID: android-verity: mark dev as rw for linear target
Mark as rw when adding as linear target to allow changes
to the underlying filesystem through adb disable verity
and adb remount.

(Cherry-picked from
https://partner-android-review.googlesource.com/#/c/613573/
79a3032bb62da65a5d724eb70c8bdc662945d475)

BUG: 28845874
Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com>
Change-Id: If41e9cad8e0f054f4778c09a6e2f0cb8af6fddaf
2017-07-20 22:33:46 +00:00
Daniel Rosenberg
d01a860b54 ANDROID: sdcardfs: Remove unnecessary lock
The mmap_sem lock does not appear to be protecting
anything, and has been removed in Samsung's more
recent versions of sdcardfs.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Change-Id: I76ff3e33002716b8384fc8be368028ed63dffe4e
Bug: 63785372
2017-07-20 22:25:22 +00:00
Martijn Coenen
76b376eac7 ANDROID: binder: don't check prio permissions on restore.
Because we have disabled RT priority inheritance for
the regular binder domain, the following can happen:

1) thread A (prio 98) calls into thread B
2) because RT prio inheritance is disabled, thread B
   runs at the lowest nice (prio 100) instead
3) thread B calls back into A; A will run at prio 100
   for the duration of the transaction
4) When thread A is done with the call from B, we will
   try to restore the prio back to 98. But, we fail
   because the process doesn't hold CAP_SYS_NICE,
   neither is RLIMIT_RT_PRIO set.

While the proper fix going forward will be to
correctly apply CAP_SYS_NICE or RLIMIT_RT_PRIO,
for now it seems reasonable to not check permissions
on the restore path.

Change-Id: Ibede5960c9b7bb786271c001e405de50be64d944
Signed-off-by: Martijn Coenen <maco@android.com>
2017-07-20 15:49:52 +02:00
Colin Cross
89ce9d97e6 Add BINDER_GET_NODE_DEBUG_INFO ioctl
The BINDER_GET_NODE_DEBUG_INFO ioctl will return debug info on
a node.  Each successive call reusing the previous return value
will return the next node.  The data will be used by
libmemunreachable to mark the pointers with kernel references
as reachable.

Bug: 28275695
Change-Id: Idbbafa648a33822dc023862cd92b51a595cf7c1c
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Martijn Coenen <maco@android.com>
2017-07-19 10:33:02 +02:00
Chris Redpath
2ee9941b0b UPSTREAM: cpufreq: schedutil: Trace frequency only if it has changed
sugov_update_commit() calls trace_cpu_frequency() to record the
current CPU frequency if it has not changed in the fast switch case
to prevent utilities from getting confused (they may report that the
CPU is idle if the frequency has not been recorded for too long, for
example).

However, that may cause the tracepoint to be triggered quite often
for no real reason (if the frequency doesn't change, we will not
modify the last update time stamp and governor computations may
run again shortly when that happens), so don't do that (arguably, it
is done to work around a utilities bug anyway).

That allows code duplication in sugov_update_commit() to be reduced
somewhat too.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
(cherry picked from commit 38d4ea229d25d30be6bf41bcd6cd663a587866ca)
(conflicts with sugov_up_down_rate_limit resolved)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: Ia019dda29b8c1c4cf3553da75c88d066eb5674e9
2017-07-18 18:18:53 +00:00
Chris Redpath
537d19226a UPSTREAM: cpufreq: schedutil: Avoid reducing frequency of busy CPUs prematurely
The way the schedutil governor uses the PELT metric causes it to
underestimate the CPU utilization in some cases.

That can be easily demonstrated by running kernel compilation on
a Sandy Bridge Intel processor, running turbostat in parallel with
it and looking at the values written to the MSR_IA32_PERF_CTL
register.  Namely, the expected result would be that when all CPUs
were 100% busy, all of them would be requested to run in the maximum
P-state, but observation shows that this clearly isn't the case.
The CPUs run in the maximum P-state for a while and then are
requested to run slower and go back to the maximum P-state after
a while again.  That causes the actual frequency of the processor to
visibly oscillate below the sustainable maximum in a jittery fashion
which clearly is not desirable.

That has been attributed to CPU utilization metric updates on task
migration that cause the total utilization value for the CPU to be
reduced by the utilization of the migrated task.  If that happens,
the schedutil governor may see a CPU utilization reduction and will
attempt to reduce the CPU frequency accordingly right away.  That
may be premature, though, for example if the system is generally
busy and there are other runnable tasks waiting to be run on that
CPU already.

This is unlikely to be an issue on systems where cpufreq policies are
shared between multiple CPUs, because in those cases the policy
utilization is computed as the maximum of the CPU utilization values
over the whole policy and if that turns out to be low, reducing the
frequency for the policy most likely is a good idea anyway.  On
systems with one CPU per policy, however, it may affect performance
adversely and even lead to increased energy consumption in some cases.

On those systems it may be addressed by taking another utilization
metric into consideration, like whether or not the CPU whose
frequency is about to be reduced has been idle recently, because if
that's not the case, the CPU is likely to be busy in the near future
and its frequency should not be reduced.

To that end, use the counter of idle calls in the timekeeping code.
Namely, make the schedutil governor look at that counter for the
current CPU every time before its frequency is about to be reduced.
If the counter has not changed since the previous iteration of the
governor computations for that CPU, the CPU has been busy for all
that time and its frequency should not be decreased, so if the new
frequency would be lower than the one set previously, the governor
will skip the frequency update.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Joel Fernandes <joelaf@google.com>
(cherry picked from commit b7eaf1aab9f8bd2e49fceed77ebc66c1b5800718)
(simple CPUFREQ_RT_DL vs CPUFREQ_DL usage conflicts)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: I531ec02c052944ee07a904dc2a25c59948ee762b
2017-07-18 18:18:46 +00:00
Chris Redpath
a8a200d83b UPSTREAM: cpufreq: schedutil: Refactor sugov_next_freq_shared()
The loop in sugov_next_freq_shared() contains an if block to skip the
loop for the current CPU. This turns out to be an unnecessary
conditional in the scheduler's hot-path for every CPU in the policy.

It would be better to drop the conditional and make the loop treat all
the CPUs in the same way. That would eliminate the need of calling
sugov_iowait_boost() at the top of the routine.

To keep the code optimized to return early if the current CPU has RT/DL
flags set, move the flags check to sugov_update_shared() instead in
order to avoid the function call entirely.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit cba1dfb57b94c234728b689d9b00d4267fa1a879)
(modified for SCHED_CPUFREQ_DL vs SCHED_CPUFREQ_RT)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: Ie046fdc8eda46821356750edd0fb6f7d077af363
2017-07-18 18:18:40 +00:00
Chris Redpath
7378c38a80 UPSTREAM: cpufreq: schedutil: Fix per-CPU structure initialization in sugov_start()
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 <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
(cherry picked from commit 4296f23ed49a15d36949458adcc66ff993dee2a8)
(we use SCHED_CPUFREQ_DL instead of SCHED_CPUFREQ_RT in cpu->flags)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: I5b837a0ee4432115d85caa1a9808ea61e1e1b07f
2017-07-18 18:18:33 +00:00
Viresh Kumar
cbaccedead UPSTREAM: cpufreq: schedutil: Pass sg_policy to get_next_freq()
get_next_freq() uses sg_cpu only to get sg_policy, which the callers of
get_next_freq() already have. Pass sg_policy instead of sg_cpu to
get_next_freq(), to make it more efficient.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit 655cb1ebff4b7918fc560502c3297af2d3c7d114)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: Ia210058da32930a6cdb18258aa679cd1a44a747e
2017-07-18 18:18:27 +00:00
Chris Redpath
0646dd3592 UPSTREAM: cpufreq: schedutil: move cached_raw_freq to struct sugov_policy
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 <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry-picked from 6c4f0fa643cb9e775dcc976e3db00d649468ff1d)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: Ie91420f710819b383947f9031da9be1f3bb7f636
2017-07-18 18:18:20 +00:00
Viresh Kumar
69fc75780d UPSTREAM: cpufreq: schedutil: Rectify comment in sugov_irq_work() function
This patch rectifies a comment present in sugov_irq_work() function to
follow proper grammar.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit d06e622d3d9206e6a2cc45a0f9a3256da8773ff4)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: Iaf996445d411725639d511432cc424086892a146
2017-07-18 18:18:13 +00:00
Chris Redpath
d9e7d036e7 UPSTREAM: cpufreq: schedutil: irq-work and mutex are only used in slow path
Execute the irq-work specific initialization/exit code only when the
fast path isn't available.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit 21ef57297b15a49b0c4dd4e7135c1a08e9a29a1c)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: Icfd68f455ef71846d799fcd2d8ec6aa1bf59573e
2017-07-18 18:18:03 +00:00