From: Thomas Hellstrom <thellstrom@vmware.com>
Date: Wed, 23 May 2018 16:13:20 +0200
Subject: drm/vmwgfx: Fix host logging / guestinfo reading error paths
Git-commit: f37230c0ad481091bc136788ff8b37dc86300c6d
Patch-mainline: v4.17-rc7
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

The error paths were leaking opened channels.
Fix by using dedicated error paths.

Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c |   48 +++++++++++++++++++++++-------------
 1 file changed, 31 insertions(+), 17 deletions(-)

--- a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
@@ -329,8 +329,6 @@ int vmw_host_get_guestinfo(const char *g
 	struct rpc_channel channel;
 	char *msg, *reply = NULL;
 	size_t reply_len = 0;
-	int ret = 0;
-
 
 	if (!vmw_msg_enabled)
 		return -ENODEV;
@@ -344,15 +342,14 @@ int vmw_host_get_guestinfo(const char *g
 		return -ENOMEM;
 	}
 
-	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM) ||
-	    vmw_send_msg(&channel, msg) ||
-	    vmw_recv_msg(&channel, (void *) &reply, &reply_len) ||
-	    vmw_close_channel(&channel)) {
-		DRM_ERROR("Failed to get %s", guest_info_param);
+	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
+		goto out_open;
 
-		ret = -EINVAL;
-	}
+	if (vmw_send_msg(&channel, msg) ||
+	    vmw_recv_msg(&channel, (void *) &reply, &reply_len))
+		goto out_msg;
 
+	vmw_close_channel(&channel);
 	if (buffer && reply && reply_len > 0) {
 		/* Remove reply code, which are the first 2 characters of
 		 * the reply
@@ -369,7 +366,17 @@ int vmw_host_get_guestinfo(const char *g
 	kfree(reply);
 	kfree(msg);
 
-	return ret;
+	return 0;
+
+out_msg:
+	vmw_close_channel(&channel);
+	kfree(reply);
+out_open:
+	*length = 0;
+	kfree(msg);
+	DRM_ERROR("Failed to get %s", guest_info_param);
+
+	return -EINVAL;
 }
 
 
@@ -400,15 +407,22 @@ int vmw_host_log(const char *log)
 		return -ENOMEM;
 	}
 
-	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM) ||
-	    vmw_send_msg(&channel, msg) ||
-	    vmw_close_channel(&channel)) {
-		DRM_ERROR("Failed to send log\n");
+	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
+		goto out_open;
 
-		ret = -EINVAL;
-	}
+	if (vmw_send_msg(&channel, msg))
+		goto out_msg;
+
+	vmw_close_channel(&channel);
+	kfree(msg);
+
+	return 0;
 
+out_msg:
+	vmw_close_channel(&channel);
+out_open:
 	kfree(msg);
+	DRM_ERROR("Failed to send log\n");
 
-	return ret;
+	return -EINVAL;
 }