tree 987b13104c42dcb337a7f9654fbc8b6edac9e99e
parent e44a5c00169df634c152bdba65c7b735eb3a7a81
author YoungJun Cho <yj44.cho@samsung.com> 1360221474 +0900
committer Inki Dae <inki.dae@samsung.com> 1361426426 +0900

drm/exynos: fix wrong pointer access at vm close.

This patch fixes wrong pointer access issue to filp->f_op and
filp->private_data.

The exynos_drm_gem_mmap_ioctl() changes filp->f_op and
filp->private_data temporarily and restore them to use
original ones in exynos_drm_gem_mmap_buffer() but there
was no lock between the changing and the restoring so
wrong pointer access to filp->f_op and filp->private_data
was induced by vm close callback.

So this patch uses mutex lock properly to resolve this issue.

Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>