Commit 3154ed36 authored Apr 10, 2017 by Sudarshan Rajagopalan Committed by Gerrit - the friendly Code Review server Apr 21, 2017

ashmem: add mutex to set size ioctl



The ioctl of ashmem is an unlocked method, hence each of its command
functions must have its own locking. Since asma->size is used at different
critical sections, it must remain unchanged until the end of the critical
section that is being executed.

Change-Id: I804604667a25976334c174ba33601bed35df3755
Signed-off-by: Sudarshan Rajagopalan <sudaraja@codeaurora.org>

parent fa403c81

drivers/staging/android/ashmem.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -766,10 +766,12 @@ static long ashmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
		break;
		case ASHMEM_SET_SIZE:
		ret = -EINVAL;
		mutex_lock(&ashmem_mutex);
		if (!asma->file) {
		ret = 0;
		asma->size = (size_t)arg;
		}
		mutex_unlock(&ashmem_mutex);
		break;
		case ASHMEM_GET_SIZE:
		ret = asma->size;