kernel/linux.git/drivers/staging/android, branch v4.14.85

staging: android: ashmem: Fix mmap size validation

2018-10-04T00:00:50+00:00

[ Upstream commit 8632c614565d0c5fdde527889601c018e97b6384 ] The ashmem driver did not check that the size/offset of the vma passed to its .mmap() function was not larger than the ashmem object being mapped. This could cause mmap() to succeed, even though accessing parts of the mapping would later fail with a segmentation fault. Ensure an error is returned by the ashmem_mmap() function if the vma size is larger than the ashmem object size. This enables safer handling of the problem in userspace. Cc: Todd Kjos Cc: devel@driverdev.osuosl.org Cc: linux-kernel@vger.kernel.org Cc: kernel-team@android.com Cc: Joel Fernandes Signed-off-by: Alistair Strachan Acked-by: Joel Fernandes (Google) Reviewed-by: Martijn Coenen Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Return an ERR_PTR in ion_map_kernel

2018-07-08T13:30:47+00:00

commit 0a2bc00341dcfcc793c0dbf4f8d43adf60458b05 upstream. The expected return value from ion_map_kernel is an ERR_PTR. The error path for a vmalloc failure currently just returns NULL, triggering a warning in ion_buffer_kmap_get. Encode the vmalloc failure as an ERR_PTR. Reported-by: syzbot+55b1d9f811650de944c6@syzkaller.appspotmail.com Signed-off-by: Laura Abbott Cc: stable Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Switch to pr_warn_once in ion_buffer_destroy

2018-06-16T07:45:15+00:00

commit 45ad559a29629cb1c64ee636563c69b71524f077 upstream. Syzbot reported yet another warning with Ion: WARNING: CPU: 0 PID: 1467 at drivers/staging/android/ion/ion.c:122 ion_buffer_destroy+0xd4/0x190 drivers/staging/android/ion/ion.c:122 Kernel panic - not syncing: panic_on_warn set ... This is catching that a buffer was freed with an existing kernel mapping still present. This can be easily be triggered from userspace by calling DMA_BUF_SYNC_START without calling DMA_BUF_SYNC_END. Switch to a single pr_warn_once to indicate the error without being disruptive. Reported-by: syzbot+cd8bcd40cb049efa2770@syzkaller.appspotmail.com Reported-by: syzbot Signed-off-by: Laura Abbott Cc: stable Signed-off-by: Greg Kroah-Hartman

staging: android: ion: Zero CMA allocated memory

2018-03-28T16:24:49+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

2018-03-24T10:01:21+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

2018-03-19T07:42:45+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: ion: Fix ion_cma_heap allocations

2018-03-03T09:24:26+00:00

[ Upstream commit f292b9b28097d8fe870336108e91bd95a14294bf ] 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 Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

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

2018-02-25T10:07:52+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

2018-02-25T10:07:49+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

2018-02-25T10:07:49+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