On Wed, 2023-03-01 at 17:07 +0100, Thomas Zimmermann wrote: > There have been reports [1][2] that vmw_cmd_dx_define_query() can > be called with ctx_node->ctx set to NULL, which results in undefined > behavior in vmw_context_cotable(). Avoid this be returning an errno > code. > > Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> > Link: https://www.cve.org/CVERecord?id=CVE-2022-38096 # 1 > Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2073 # 2 > Cc: stable@xxxxxxxxxxxxxxx > --- > drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c > b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c > index 6b9aa2b4ef54..1e90362add96 100644 > --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c > +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c > @@ -1256,7 +1256,7 @@ static int vmw_cmd_dx_define_query(struct vmw_private > *dev_priv, > struct vmw_resource *cotable_res; > int ret; > > - if (!ctx_node) > + if (!ctx_node || !ctx_node->ctx) > return -EINVAL; I've seen this report, but never a poc that could reproduce it. This should never happen, the ctx in ctx_node should have been initialized. To be honest I'd prefer to just figure out how it's uninitialised instead of just checking for something that should be impossible but without a reproducible test that's difficult. z
