From: Daniel Vetter daniel.vetter@ffwll.ch
[ Upstream commit 5bf8bec3f4ce044a223c40cbce92590d938f0e9c ]
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 Signed-off-by: Sasha Levin sashal@kernel.org --- 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 cdb10f885a4f..69dfed57c2f8 100644 --- a/drivers/gpu/drm/drm_property.c +++ b/drivers/gpu/drm/drm_property.c @@ -556,7 +556,7 @@ 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);