drm/i915: restrict kernel address leak in debugfs

Masks kernel address info-leak in object dumps with the %pK suffix,
so they cannot be used to target kernel memory corruption attacks if
the kptr_restrict sysctl is set.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index aae3148..7299ea4 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -103,7 +103,7 @@ static const char *cache_level_str(int type)
 static void
 describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
 {
-       seq_printf(m, "%p: %s%s %8zdKiB %02x %02x %d %d %d%s%s%s",
+       seq_printf(m, "%pK: %s%s %8zdKiB %02x %02x %d %d %d%s%s%s",
                   &obj->base,
                   get_pin_flag(obj),
                   get_tiling_flag(obj),