From 65b3bdc807ac7bd83f5b27bc2c29a3c631eed7dd Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 22 May 2018 13:10:18 +0100 Subject: [PATCH] drm/i915/query: nospec expects no more than an unsigned long nospec quite reasonably asserts that it will never be used with an index larger than unsigned long (that being the largest possibly index into an C array). However, our ubi uses the convention of u64 for any large integer, running afoul of the assertion on 32b. Reduce our index to an unsigned long, checking for type overflow first. drivers/gpu/drm/i915/i915_query.c: In function 'i915_query_ioctl': include/linux/compiler.h:339:38: error: call to '__compiletime_assert_119' declared with attribute error: BUILD_BUG_ON failed: sizeof(_s) > sizeof(long) Reported-by: kbuild-all@01.org Fixes: 84b510e22da7 ("drm/i915/query: Protect tainted function pointer lookup") Signed-off-by: Chris Wilson Cc: Lionel Landwerlin Cc: Joonas Lahtinen Cc: Tvrtko Ursulin Reviewed-by: Lionel Landwerlin Link: https://patchwork.freedesktop.org/patch/msgid/20180522121018.15199-1-chris@chris-wilson.co.uk (cherry picked from commit a33b1dc8a732144e11cb4bf067d24ba51e6b8ab0) Signed-off-by: Joonas Lahtinen --- drivers/gpu/drm/i915/i915_query.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_query.c b/drivers/gpu/drm/i915/i915_query.c index 95f9d17..3f502ee 100644 --- a/drivers/gpu/drm/i915/i915_query.c +++ b/drivers/gpu/drm/i915/i915_query.c @@ -102,7 +102,7 @@ int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file) for (i = 0; i < args->num_items; i++, user_item_ptr++) { struct drm_i915_query_item item; - u64 func_idx; + unsigned long func_idx; int ret; if (copy_from_user(&item, user_item_ptr, sizeof(item))) @@ -111,6 +111,9 @@ int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file) if (item.query_id == 0) return -EINVAL; + if (overflows_type(item.query_id - 1, unsigned long)) + return -EINVAL; + func_idx = item.query_id - 1; ret = -EINVAL; -- 2.7.4