[PATCH] dix: avoid calling deleted block and wakeup handlers

[Scott James Remnant]

BlockHandler and WakeupHandlers may be removed within a different
BlockHandler or WakeupHandler, especially since config/udev uses
these and removes devices.

Calling the deleted handlers and passing potentially freed data
can result in the X server segfaulting after device removal, or
events that result in device removal such as undocking or suspend/
resume.

Signed-off-by: Scott James Remnant <scott at netsplit.com>
---
 dix/dixutils.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/dix/dixutils.c b/dix/dixutils.c
index 104363b..1e31346 100644
--- a/dix/dixutils.c
+++ b/dix/dixutils.c
@@ -386,8 +386,9 @@ BlockHandler(pointer pTimeout, pointer pReadmask)
 				screenInfo.screens[i]->blockData,
 				pTimeout, pReadmask);
     for (i = 0; i < numHandlers; i++)
-	(*handlers[i].BlockHandler) (handlers[i].blockData,
-				     pTimeout, pReadmask);
+	if (!handlers[i].deleted)
+		(*handlers[i].BlockHandler) (handlers[i].blockData,
+					     pTimeout, pReadmask);
     if (handlerDeleted)
     {
 	for (i = 0; i < numHandlers;)
@@ -416,8 +417,9 @@ WakeupHandler(int result, pointer pReadmask)
 
     ++inHandler;
     for (i = numHandlers - 1; i >= 0; i--)
-	(*handlers[i].WakeupHandler) (handlers[i].blockData,
-				      result, pReadmask);
+	if (!handlers[i].deleted)
+		(*handlers[i].WakeupHandler) (handlers[i].blockData,
+					      result, pReadmask);
     for (i = 0; i < screenInfo.numScreens; i++)
 	(* screenInfo.screens[i]->WakeupHandler)(i, 
 				screenInfo.screens[i]->wakeupData,
-- 
1.7.3.1