Commit 2e132aff authored Jun 12, 2015 by Arun Menon Committed by Gerrit - the friendly Code Review server Jun 15, 2015

[media] videobuf2-core: Add null check for current->mm in buf_prepare



If current->mm is NULL, then buf_prepare ends up using
garbage semaphor value from current->mm->mmap_sem during
down_read. This results in a device crash. This change
fixes the issue.

Change-Id: I9096c7d674d2493def1ce57ece551e7cd8f9e298
Signed-off-by: Arun Menon <avmenon@codeaurora.org>

parent a5eb2c93

drivers/media/v4l2-core/videobuf2-core.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1591,7 +1591,10 @@ static int __buf_prepare(struct vb2_buffer vb, const struct v4l2_buffer b)
		{
		struct vb2_queue *q = vb->vb2_queue;
		int ret;
		struct rw_semaphore *mmap_sem = &current->mm->mmap_sem;
		struct rw_semaphore *mmap_sem = NULL;

		if (current && current->mm)
		mmap_sem = &current->mm->mmap_sem;

		ret = __verify_length(vb, b);
		if (ret < 0) {