From 5bf8bec3f4ce044a223c40cbce92590d938f0e9c Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed, 4 Dec 2019 16:52:37 -0800
Subject: [PATCH] drm: limit to INT_MAX in create_blob ioctl
Git-commit: 5bf8bec3f4ce044a223c40cbce92590d938f0e9c
Patch-mainline: v5.5-rc1
References: bsc#1051510
The hardened usercpy code is too paranoid ever since commit 6a30afa8c1fb
("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@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reported-by: syzbot+fb77e97ebf0612ee6914@syzkaller.appspotmail.com
Fixes: 6a30afa8c1fb ("uaccess: disallow > INT_MAX copy sizes")
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/drm_property.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_property.c b/drivers/gpu/drm/drm_property.c
index 892ce636ef72..6ee04803c362 100644
--- a/drivers/gpu/drm/drm_property.c
+++ b/drivers/gpu/drm/drm_property.c
@@ -561,7 +561,7 @@ drm_property_create_blob(struct drm_device *dev, size_t length,
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);
--
2.16.4