From: Nirmoy Das <[email protected]> [ Upstream commit 9c1813b3253480b30604c680026c7dc721ce86d1 ]
access_ok() only checks for addr overflow so also try to read the addr to catch invalid addr sent from userspace. Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1630 Cc: Francois Dugast <[email protected]> Cc: Maarten Lankhorst <[email protected]> Cc: Matthew Auld <[email protected]> Cc: Matthew Brost <[email protected]> Reviewed-by: Matthew Brost <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Nirmoy Das <[email protected]> (cherry picked from commit 9408c4508483ffc60811e910a93d6425b8e63928) Signed-off-by: Lucas De Marchi <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/gpu/drm/xe/xe_sync.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_sync.c b/drivers/gpu/drm/xe/xe_sync.c index de80c8b7c8913..9d77f2d4096f5 100644 --- a/drivers/gpu/drm/xe/xe_sync.c +++ b/drivers/gpu/drm/xe/xe_sync.c @@ -54,8 +54,9 @@ static struct xe_user_fence *user_fence_create(struct xe_device *xe, u64 addr, { struct xe_user_fence *ufence; u64 __user *ptr = u64_to_user_ptr(addr); + u64 __maybe_unused prefetch_val; - if (!access_ok(ptr, sizeof(*ptr))) + if (get_user(prefetch_val, ptr)) return ERR_PTR(-EFAULT); ufence = kzalloc(sizeof(*ufence), GFP_KERNEL); -- 2.43.0
