From: Daniel Vetter <daniel.vetter@xxxxxxxx>
Subject: drm: limit to INT_MAX in create_blob ioctl
The hardened usercpy code is too paranoid ever since:
commit 6a30afa8c1fbde5f10f9c584c2992aa3c7f7a8fe
Author: Kees Cook <keescook@xxxxxxxxxxxx>
Date: Wed Nov 6 16:07:01 2019 +1100
uaccess: disallow > INT_MAX copy sizes
Code itself should have been fine as-is.
Link: http://lkml.kernel.org/r/20191106164755.31478-1-daniel.vetter@xxxxxxxx
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Reported-by: syzbot+fb77e97ebf0612ee6914@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 6a30afa8c1fb ("uaccess: disallow > INT_MAX copy sizes")
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_property.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/drm_property.c~drm-limit-to-int_max-in-create_blob-ioctl
+++ a/drivers/gpu/drm/drm_property.c
@@ -561,7 +561,7 @@ drm_property_create_blob(struct drm_devi
struct drm_property_blob *blob;
int ret;
- if (!length || length > ULONG_MAX - sizeof(struct drm_property_blob))
+ if (!length || length > INT_MAX - sizeof(struct drm_property_blob))
return ERR_PTR(-EINVAL);
blob = kvzalloc(sizeof(struct drm_property_blob)+length, GFP_KERNEL);
_
