From: Lao Wei Date: Mon, 9 Jul 2018 12:15:53 +0000 (-0400) Subject: media: fix: media: pci: meye: validate offset to avoid arbitrary access X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=eac7230fdb4672c2cb56f6a01a1744f562c01f80;p=openwrt%2Fstaging%2Fblogic.git media: fix: media: pci: meye: validate offset to avoid arbitrary access Motion eye video4linux driver for Sony Vaio PictureBook desn't validate user-controlled parameter 'vma->vm_pgoff', a malicious process might access all of kernel memory from user space by trying pass different arbitrary address. Discussion: http://www.openwall.com/lists/oss-security/2018/07/06/1 Signed-off-by: Lao Wei Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/pci/meye/meye.c b/drivers/media/pci/meye/meye.c index 7285edcdd323..bd870e60c32b 100644 --- a/drivers/media/pci/meye/meye.c +++ b/drivers/media/pci/meye/meye.c @@ -1460,7 +1460,7 @@ static int meye_mmap(struct file *file, struct vm_area_struct *vma) unsigned long page, pos; mutex_lock(&meye.lock); - if (size > gbuffers * gbufsize) { + if (size > gbuffers * gbufsize || offset > gbuffers * gbufsize - size) { mutex_unlock(&meye.lock); return -EINVAL; }