[PATCH] drm/vmwgfx: Handle surface check failure correctly

From: Nikolay Kuratov
Date: Wed Oct 02 2024 - 08:28:17 EST


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@xxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 810b3e1683d0 ("drm/vmwgfx: Support topology greater than texture size")
---
drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 288ed0bb75cb..752510a11e1b 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -1539,6 +1539,7 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
DRM_ERROR("Surface size cannot exceed %dx%d\n",
dev_priv->texture_max_width,
dev_priv->texture_max_height);
+ ret = -EINVAL;
goto err_out;
}

--
2.34.1