oss-sec mailing list archives
Re: mmap vulnerability in motion eye video4linux driver for Sony Vaio PictureBook
From: Solar Designer <solar () openwall com>
Date: Fri, 6 Jul 2018 16:54:22 +0200
On Fri, Jul 06, 2018 at 03:26:55PM +0200, Greg KH wrote:
On Fri, Jul 06, 2018 at 08:35:43PM +0800, zrlw () sina com wrote:Hi all,i found a vulnerability in motion eye video4linux driver for Sony Vaio PictureBook,it 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. /usr/src/linux-4.4.21-69/drivers/media/pci/meye/meye.c: static int meye_mmap(struct file *file, struct vm_area_struct *vma) ... unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; ... pos = (unsigned long)meye.grab_fbuffer + offset; while (size > 0) { page = vmalloc_to_pfn((void *)pos); if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) {...Commit: be83bbf80682 ("mmap: introduce sane default mmap limits") which was backported to all stable kernels, should have resolved this problem, correct? If not, please notify the media driver maintainers and they will be glad to fix the problem.
I think zrlw () sina com is not subscribed, so CC'ing. I wonder if it's also possible to cause integer overflow on "(unsigned long)meye.grab_fbuffer + offset", bringing pos below meye.grab_fbuffer, and what the impact of that would be. Alexander
Current thread:
- mmap vulnerability in motion eye video4linux driver for Sony Vaio PictureBook zrlw (Jul 06)
- Re: mmap vulnerability in motion eye video4linux driver for Sony Vaio PictureBook Greg KH (Jul 06)
- Re: mmap vulnerability in motion eye video4linux driver for Sony Vaio PictureBook Solar Designer (Jul 06)
- <Possible follow-ups>
- Re: mmap vulnerability in motion eye video4linux driver for Sony Vaio PictureBook zrlw (Jul 06)
- Re: mmap vulnerability in motion eye video4linux driver for Sony Vaio PictureBook Greg KH (Jul 06)