drm/vmwgfx: Handle surface check failure correctly

commit 26498b8d54373d31a621d7dec95c4bd842563b3b upstream.

Currently if condition (!bo and !vmw_kms_srf_ok()) was met
we go to err_out with ret == 0.
err_out dereferences vfb if ret == 0, but in our case vfb is still NULL.

Fix this by assigning sensible error to ret.

Found by Linux Verification Center (linuxtesting.org) with SVACE

Signed-off-by: Nikolay Kuratov <kniv@yandex-team.ru>
Cc: stable@vger.kernel.org
Fixes: 810b3e1683d0 ("drm/vmwgfx: Support topology greater than texture size")
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241002122429.1981822-1-kniv@yandex-team.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 0e963fd7db17e73ffb1bfe7deac81843bd08b908..73cbb94ff456b1616ce1527497d066a2e428c5b7 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -1402,6 +1402,7 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
                DRM_ERROR("Surface size cannot exceed %dx%d",
                        dev_priv->texture_max_width,
                        dev_priv->texture_max_height);
+               ret = -EINVAL;
                goto err_out;
        }