From 598781d71119827b454fd75d46f84755bca6f0c6 Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Tue, 24 Jan 2012 18:54:21 +0100 Subject: drm: Fix authentication kernel crash If the master tries to authenticate a client using drm_authmagic and that client has already closed its drm file descriptor, either wilfully or because it was terminated, the call to drm_authmagic will dereference a stale pointer into kmalloc'ed memory and corrupt it. Typically this results in a hard system hang. This patch fixes that problem by removing any authentication tokens (struct drm_magic_entry) open for a file descriptor when that file descriptor is closed. Signed-off-by: Thomas Hellstrom Reviewed-by: Daniel Vetter Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie --- include/drm/drmP.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 76caa67c22e..92f0981b5fb 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1328,6 +1328,7 @@ extern int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv); extern int drm_authmagic(struct drm_device *dev, void *data, struct drm_file *file_priv); +extern int drm_remove_magic(struct drm_master *master, drm_magic_t magic); /* Cache management (drm_cache.c) */ void drm_clflush_pages(struct page *pages[], unsigned long num_pages); -- cgit v1.2.3