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From: Eric Paris <eparis@redhat.com>
To: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Cc: viro@ZenIV.linux.org.uk, linux-fsdevel@vger.kernel.org,
	vasily.novikov@kaspersky.com
Subject: Re: [PATCH] fs, fanotify: dont send notification event for coredump file
Date: Mon, 26 Mar 2012 13:03:43 -0400	[thread overview]
Message-ID: <1332781423.384.1.camel@localhost> (raw)
In-Reply-To: <20120325012813.GD3276@Neptun>

On Sun, 2012-03-25 at 03:28 +0200, Lino Sanfilippo wrote:
> Currently fsnotify events are created for core dump files. This may
> lead to problems if a listener has registered with fanotify to watch
> permission events for the whole filesystem:
> If it is the listener itself that causes the creation of a core dump file
> (due to a segfault) a permission event is created but never granted
> (the listener is not running any more).
> OTOH the listener cant unregister either, since its waiting for its own
> ack. Since no file accesses are answered any more, eventually the whole
> system freezes.
> 
> This patch solves the problem by allowing the core dump file to be
> created without sending a notification event. For this reason the
> FMODE_NONOTIFY flag is no longer cleared in build_open_flags() but
> in the caller. Furthermore it is set for the creation of the core dump
> file.
> Also callers of filp_open() are now able to specify FMODE_NONOTIFY if
> they dont want notification events to be created for an opened file.
> 
> Reported-by: Vasily Novikov <vasily.novikov@kaspersky.com>
> Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>

How does this work with something like abrt, which causes core files to
be created in a known dir.  It then watches (I have no idea if it uses
*notify) for new core files and processes them when they appear.  Would
we be able to get any notification of core files with this patch?  Maybe
we need a way to just not allow ourselves to block on core files?


  reply	other threads:[~2012-03-26 18:56 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-03-25  1:28 [PATCH] fs, fanotify: dont send notification event for coredump file Lino Sanfilippo
2012-03-26 17:03 ` Eric Paris [this message]
2012-03-26 22:27   ` Lino Sanfilippo

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