From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Jackson <Ian.Jackson@eu.citrix.com>
Subject: Re: [PATCH 2/2] libxl: fix stale timeout event callback
 race
Date: Wed, 12 Dec 2012 17:16:04 +0000
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To: Jim Fehlig <jfehlig@suse.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>, Ian Campbell <Ian.Campbell@citrix.com>, Bamvor Jian Zhang <bjzhang@suse.com>
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Ian Jackson writes ("Re: [Xen-devel] [PATCH 2/2] libxl: fix stale timeout event callback race"):
> Jim Fehlig writes ("Re: [Xen-devel] [PATCH 2/2] libxl: fix stale timeout event callback race"):
> > - gettimeofday(&now, NULL);
> > - timeout = (abs_t.tv_usec - now.tv_usec) / 1000;
> > - timeout += (abs_t.tv_sec - now.tv_sec) * 1000;
> 
> Specifically, this code has an integer arithmetic overflow.

If you look at beforepoll_internal in libxl_event.c, near line 859,
you can see how I tackled this same problem there.

Ian.