linux-stable.git/drivers/staging/android, branch linux-4.15.y

staging: android: ion: Zero CMA allocated memory

2018-03-28T16:23:04+00:00

commit 6d79bd5bb6c79a9dba4842040c9adf39e7806330 upstream.

Since commit 204f672255c2 ("staging: android: ion: Use CMA APIs directly")
the CMA API is now used directly and therefore the allocated memory is no
longer automatically zeroed.

Explicitly zero CMA allocated memory to ensure that no data is exposed to
userspace.

Fixes: 204f672255c2 ("staging: android: ion: Use CMA APIs directly")
Signed-off-by: Liam Mark 
Acked-by: Laura Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: android: ashmem: Fix possible deadlock in ashmem_ioctl

2018-03-24T10:02:43+00:00

commit 740a5759bf222332fbb5eda42f89aa25ba38f9b2 upstream.

ashmem_mutex may create a chain of dependencies like:

CPU0                                    CPU1
 mmap syscall                           ioctl syscall
 -> mmap_sem (acquired)                 -> ashmem_ioctl
 -> ashmem_mmap                            -> ashmem_mutex (acquired)
    -> ashmem_mutex (try to acquire)       -> copy_from_user
                                              -> mmap_sem (try to acquire)

There is a lock odering problem between mmap_sem and ashmem_mutex causing
a lockdep splat[1] during a syzcaller test. This patch fixes the problem
by move copy_from_user out of ashmem_mutex.

[1] https://www.spinics.net/lists/kernel/msg2733200.html

Fixes: ce8a3a9e76d0 (staging: android: ashmem: Fix a race condition in pin ioctls)
Reported-by: syzbot+d7a918a7a8e1c952bc36@syzkaller.appspotmail.com
Signed-off-by: Yisheng Xie 
Cc: "Joel Fernandes (Google)" 
Signed-off-by: Greg Kroah-Hartman

staging: android: ashmem: Fix lockdep issue during llseek

2018-03-19T08:09:47+00:00

commit cb57469c9573f6018cd1302953dd45d6e05aba7b upstream.

ashmem_mutex create a chain of dependencies like so:

(1)
mmap syscall ->
  mmap_sem ->  (acquired)
  ashmem_mmap
  ashmem_mutex (try to acquire)
  (block)

(2)
llseek syscall ->
  ashmem_llseek ->
  ashmem_mutex ->  (acquired)
  inode_lock ->
  inode->i_rwsem (try to acquire)
  (block)

(3)
getdents ->
  iterate_dir ->
  inode_lock ->
  inode->i_rwsem   (acquired)
  copy_to_user ->
  mmap_sem         (try to acquire)

There is a lock ordering created between mmap_sem and inode->i_rwsem
causing a lockdep splat [2] during a syzcaller test, this patch fixes
the issue by unlocking the mutex earlier. Functionally that's Ok since
we don't need to protect vfs_llseek.

[1] https://patchwork.kernel.org/patch/10185031/
[2] https://lkml.org/lkml/2018/1/10/48

Acked-by: Todd Kjos 
Cc: Arve Hjonnevag 
Cc: stable@vger.kernel.org
Reported-by: syzbot+8ec30bb7bf1a981a2012@syzkaller.appspotmail.com
Signed-off-by: Joel Fernandes 
Acked-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

staging: android: ashmem: Fix a race condition in pin ioctls

2018-02-25T10:15:42+00:00

commit ce8a3a9e76d0193e2e8d74a06d275b3c324ca652 upstream.

ashmem_pin_unpin() reads asma->file and asma->size before taking the
ashmem_mutex, so it can race with other operations that modify them.

Build-tested only.

Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Switch from WARN to pr_warn

2018-02-25T10:15:39+00:00

commit e4e179a844f52e907e550f887d0a2171f1508af1 upstream.

Syzbot reported a warning with Ion:

WARNING: CPU: 0 PID: 3502 at drivers/staging/android/ion/ion-ioctl.c:73 ion_ioctl+0x2db/0x380 drivers/staging/android/ion/ion-ioctl.c:73
Kernel panic - not syncing: panic_on_warn set ...

This is a warning that validation of the ioctl fields failed. This was
deliberately added as a warning to make it very obvious to developers that
something needed to be fixed. In reality, this is overkill and disturbs
fuzzing. Switch to pr_warn for a message instead.

Reported-by: syzbot+fa2d5f63ee5904a0115a@syzkaller.appspotmail.com
Reported-by: syzbot 
Signed-off-by: Laura Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Add __GFP_NOWARN for system contig heap

2018-02-25T10:15:39+00:00

commit 0c75f10312a35b149b2cebb1832316b35c2337ca upstream.

syzbot reported a warning from Ion:

  WARNING: CPU: 1 PID: 3485 at mm/page_alloc.c:3926

  ...
   __alloc_pages_nodemask+0x9fb/0xd80 mm/page_alloc.c:4252
  alloc_pages_current+0xb6/0x1e0 mm/mempolicy.c:2036
  alloc_pages include/linux/gfp.h:492 [inline]
  ion_system_contig_heap_allocate+0x40/0x2c0
  drivers/staging/android/ion/ion_system_heap.c:374
  ion_buffer_create drivers/staging/android/ion/ion.c:93 [inline]
  ion_alloc+0x2c1/0x9e0 drivers/staging/android/ion/ion.c:420
  ion_ioctl+0x26d/0x380 drivers/staging/android/ion/ion-ioctl.c:84
  vfs_ioctl fs/ioctl.c:46 [inline]
  do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
  SYSC_ioctl fs/ioctl.c:701 [inline]
  SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692

This is a warning about attempting to allocate order > MAX_ORDER. This
is coming from a userspace Ion allocation request. Since userspace is
free to request however much memory it wants (and the kernel is free to
deny its allocation), silence the allocation attempt with __GFP_NOWARN
in case it fails.

Reported-by: syzbot+76e7efc4748495855a4d@syzkaller.appspotmail.com
Reported-by: syzbot 
Signed-off-by: Laura Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: android: ashmem: fix a race condition in ASHMEM_SET_SIZE ioctl

2018-01-09T14:32:11+00:00

A lock-unlock is missing in ASHMEM_SET_SIZE ioctl which can result in a
race condition when mmap is called. After the !asma->file check, before
setting asma->size, asma->file can be set in mmap. That would result in
having different asma->size than the mapped memory size. Combined with
ASHMEM_UNPIN ioctl and shrinker invocation, this can result in memory
corruption.

Signed-off-by: Viktor Slavkovic 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Fix dma direction for dma_sync_sg_for_cpu/device

2017-12-19T14:53:39+00:00

Use the direction argument passed into begin_cpu_access
and end_cpu_access when calling the dma_sync_sg_for_cpu/device.
The actual cache primitive called depends on the direction
passed in.

Signed-off-by: Sushmita Susheelendra 
Cc: stable 
Acked-by: Laura Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: ion: Fix ion_cma_heap allocations

2017-12-19T14:53:39+00:00

In trying to add support for drm_hwcomposer to HiKey,
I've needed to utilize the ION CMA heap, and I've noticed
problems with allocations on newer kernels failing.

It seems back with 204f672255c2 ("ion: Use CMA APIs directly"),
the ion_cma_heap code was modified to use the CMA API, but
kept the arguments as buffer lengths rather then number of pages.

This results in errors as we don't have enough pages in CMA to
satisfy the exaggerated requests.

This patch converts the ion_cma_heap CMA API usage to properly
request pages.

It also fixes a minor issue in the allocation where in the error
path, the cma_release is called with the buffer->size value which
hasn't yet been set.

Cc: Laura Abbott 
Cc: Sumit Semwal 
Cc: Benjamin Gaignard 
Cc: Archit Taneja 
Cc: Greg KH 
Cc: Daniel Vetter 
Cc: Dmitry Shmidt 
Cc: Todd Kjos 
Cc: Amit Pundir 
Fixes: 204f672255c2 ("staging: android: ion: Use CMA APIs directly")
Acked-by: Laura Abbott 
Signed-off-by: John Stultz 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'staging-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

2017-11-14T04:53:28+00:00

Pull staging and IIO updates from Greg KH:
 "Here is the "big" staging and IIO driver update for 4.15-rc1.

  Lots and lots of little changes, almost all minor code cleanups as the
  Outreachy application process happened during this development cycle.
  Also happened was a lot of IIO driver activity, and the typec USB code
  moving out of staging to drivers/usb (same commits are in the USB tree
  on a persistent branch to not cause merge issues.)

  Overall, it's a wash, I think we added a few hundred more lines than
  removed, but really only a few thousand were modified at all.

  All of these have been in linux-next for a while. There might be a
  merge issue with Al's vfs tree in the pi433 driver (take his changes,
  they are always better), and the media tree with some of the odd
  atomisp cleanups (take the media tree's version)"

* tag 'staging-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (507 commits)
  staging: lustre: add SPDX identifiers to all lustre files
  staging: greybus: Remove redundant license text
  staging: greybus: add SPDX identifiers to all greybus driver files
  staging: ccree: simplify ioread/iowrite
  staging: ccree: simplify registers access
  staging: ccree: simplify error handling logic
  staging: ccree: remove dead code
  staging: ccree: handle limiting of DMA masks
  staging: ccree: copy IV to DMAable memory
  staging: fbtft: remove redundant initialization of buf
  staging: sm750fb: Fix parameter mistake in poke32
  staging: wilc1000: Fix bssid buffer offset in Txq
  staging: fbtft: fb_ssd1331: fix mirrored display
  staging: android: Fix checkpatch.pl error
  staging: greybus: loopback: convert loopback to use generic async operations
  staging: greybus: operation: add private data with get/set accessors
  staging: greybus: loopback: Fix iteration count on async path
  staging: greybus: loopback: Hold per-connection mutex across operations
  staging: greybus/loopback: use ktime_get() for time intervals
  staging: fsl-dpaa2/eth: Extra headroom in RX buffers
  ...