[PATCH 1/3] nouveau: cleanup error handling during nouveau_device_wrap

[Emil Velikov]

In theory it's possible for any of the nouveau_getparam calls to
fail whist the last one being successful.

Thus at least one of the following (hard requirements) drmVersion,
chipset and vram/gart memory size will be filled with garbage and
sent to the userspace drivers.

Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
---
 nouveau/nouveau.c | 30 +++++++++++++++++++-----------
 1 file changed, 19 insertions(+), 11 deletions(-)

diff --git a/nouveau/nouveau.c b/nouveau/nouveau.c
index ee7893b..d6013db 100644
--- a/nouveau/nouveau.c
+++ b/nouveau/nouveau.c
@@ -88,27 +88,32 @@ nouveau_device_wrap(int fd, int close, struct nouveau_device **pdev)
 	nvdev->base.fd = fd;
 
 	ver = drmGetVersion(fd);
-	if (ver) dev->drm_version = (ver->version_major << 24) |
-				    (ver->version_minor << 8) |
-				     ver->version_patchlevel;
+	if (!ver) {
+		ret = -errno;
+		goto error;
+	}
+
+	dev->drm_version = (ver->version_major << 24) |
+			    (ver->version_minor << 8) |
+			     ver->version_patchlevel;
 	drmFreeVersion(ver);
 
 	if ( dev->drm_version != 0x00000010 &&
 	    (dev->drm_version <  0x01000000 ||
 	     dev->drm_version >= 0x02000000)) {
-		nouveau_device_del(&dev);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto error;
 	}
 
 	ret = nouveau_getparam(dev, NOUVEAU_GETPARAM_CHIPSET_ID, &chipset);
-	if (ret == 0)
+	if (ret)
+		goto error;
 	ret = nouveau_getparam(dev, NOUVEAU_GETPARAM_FB_SIZE, &vram);
-	if (ret == 0)
+	if (ret)
+		goto error;
 	ret = nouveau_getparam(dev, NOUVEAU_GETPARAM_AGP_SIZE, &gart);
-	if (ret) {
-		nouveau_device_del(&dev);
-		return ret;
-	}
+	if (ret)
+		goto error;
 
 	ret = nouveau_getparam(dev, NOUVEAU_GETPARAM_HAS_BO_USAGE, &bousage);
 	if (ret == 0)
@@ -139,6 +144,9 @@ nouveau_device_wrap(int fd, int close, struct nouveau_device **pdev)
 
 	*pdev = &nvdev->base;
 	return 0;
+error:
+	nouveau_device_del(&dev);
+	return -ret;
 }
 
 int
-- 
1.9.0