Blame SOURCES/0004-fix-possible-server-deadlock-in-ih_sub_cancel.patch

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From f9c67a13af33f389429e4e760f2023a23a9ac19f Mon Sep 17 00:00:00 2001
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From: Anssi Hannula <anssi@mageia.org>
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Date: Wed, 4 Jan 2012 00:23:55 +0200
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Subject: [PATCH 4/4] fix possible server deadlock in ih_sub_cancel
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ih_sub_foreach() calls ih_sub_cancel() while inotify_lock is locked.
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However, ih_sub_cancel() locks it again, and locking GMutex recursively
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causes undefined behaviour.
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Fix that by removing locking from ih_sub_cancel() as ih_sub_foreach()
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is its only user. Also make the function static so that it won't
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accidentally get used by other files without locking (inotify-helper.h
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is an internal server header).
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This should fix the intermittent deadlocks I've been experiencing
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causing KDE applications to no longer start, and probably also
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http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=542361
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---
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 server/inotify-helper.c | 7 ++-----
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 server/inotify-helper.h | 1 -
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 2 files changed, 2 insertions(+), 6 deletions(-)
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diff --git a/server/inotify-helper.c b/server/inotify-helper.c
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index d77203e..0789fa4 100644
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--- a/server/inotify-helper.c
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+++ b/server/inotify-helper.c
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@@ -123,13 +123,11 @@ ih_sub_add (ih_sub_t * sub)
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 /**
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  * Cancels a subscription which was being monitored.
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+ * inotify_lock must be held when calling.
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  */
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-gboolean
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+static gboolean
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 ih_sub_cancel (ih_sub_t * sub)
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 {
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-	G_LOCK(inotify_lock);
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-
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-
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 	if (!sub->cancelled)
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 	{
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 		IH_W("cancelling %s\n", sub->pathname);
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@@ -140,7 +138,6 @@ ih_sub_cancel (ih_sub_t * sub)
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 		sub_list = g_list_remove (sub_list, sub);
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 	}
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-	G_UNLOCK(inotify_lock);
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 	return TRUE;
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 }
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diff --git a/server/inotify-helper.h b/server/inotify-helper.h
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index 5d3b6d0..d36b5fd 100644
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--- a/server/inotify-helper.h
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+++ b/server/inotify-helper.h
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@@ -34,7 +34,6 @@ gboolean	 ih_startup		(event_callback_t ecb,
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 					 found_callback_t fcb);
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 gboolean	 ih_running		(void);
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 gboolean	 ih_sub_add		(ih_sub_t *sub);
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-gboolean	 ih_sub_cancel		(ih_sub_t *sub);
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 /* Return FALSE from 'f' if the subscription should be cancelled */
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 void		 ih_sub_foreach		(void *callerdata, gboolean (*f)(ih_sub_t *sub, void *callerdata));
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-- 
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2.5.0
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