From 346add7834557b5b9628b9bf2387106d42e631d4 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Tue, 14 Jul 2015 18:07:30 +0200 Subject: [PATCH] drm/i915: Use expcitly fixed type in compat32 structs I was confused shortly whether the compat was needed for the int, until I noticed the pointer in the original. Also remove typedef. v2: Review from Chris. - Add comments. - Also change the int param in the original structure. Cc: Chris Wilson Signed-off-by: Daniel Vetter Reviewed-by: Chris Wilson Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_ioc32.c | 13 +++++++++---- include/uapi/drm/i915_drm.h | 6 +++++- 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_ioc32.c b/drivers/gpu/drm/i915/i915_ioc32.c index 6eec2221b44e..a5a2d5b3f44b 100644 --- a/drivers/gpu/drm/i915/i915_ioc32.c +++ b/drivers/gpu/drm/i915/i915_ioc32.c @@ -35,15 +35,20 @@ #include #include "i915_drv.h" -typedef struct drm_i915_getparam32 { - int param; +struct drm_i915_getparam32 { + s32 param; + /* + * We screwed up the generic ioctl struct here and used a variable-sized + * pointer. Use u32 in the compat struct to match the 32bit pointer + * userspace expects. + */ u32 value; -} drm_i915_getparam32_t; +}; static int compat_i915_getparam(struct file *file, unsigned int cmd, unsigned long arg) { - drm_i915_getparam32_t req32; + struct drm_i915_getparam32 req32; drm_i915_getparam_t __user *request; if (copy_from_user(&req32, (void __user *)arg, sizeof(req32))) diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index e7c29f1659ad..192027b4f031 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -358,7 +358,11 @@ typedef struct drm_i915_irq_wait { #define I915_PARAM_HAS_RESOURCE_STREAMER 36 typedef struct drm_i915_getparam { - int param; + s32 param; + /* + * WARNING: Using pointers instead of fixed-size u64 means we need to write + * compat32 code. Don't repeat this mistake. + */ int __user *value; } drm_i915_getparam_t; -- 2.20.1