Date: Mon, 22 Mar 2010 16:06:10 -0400 From: John Baldwin <jhb@freebsd.org> To: Alexander Best <alexbestms@wwu.de> Cc: freebsd-hackers@freebsd.org Subject: Re: [patch] somebody please fix this outstanding mmap(2) bug Message-ID: <201003221606.10924.jhb@freebsd.org> In-Reply-To: <permail-201003221946531e86ffa800005027-a_best01@message-id.uni-muenster.de> References: <permail-201003221946531e86ffa800005027-a_best01@message-id.uni-muenster.de>
next in thread | previous in thread | raw e-mail | index | archive | help
On Monday 22 March 2010 3:46:53 pm Alexander Best wrote: > John Baldwin schrieb am 2010-03-22: > > On Monday 22 March 2010 11:07:43 am Alexander Best wrote: > > > could somebody please commit this patch? it's been around forever > > > (2003 or > > > 2004) and fixes mmap so the offset argument is being ignored when > > > MAP_ANON > > is > > > defined (just like the mmap(2) manual says). right now the offset > > > argument > > is > > > being taken into account although MAP_ANON is set!!! > > > > the pr is kern/71258 (including a little c app to demonstrate the > > > bug) > > > > i've also sent a followup patch to the pr which returns EINVAL if > > > the offset > > > is non zero and MAP_ANON is set, but i guess that might break some > > > code. > > > I think we should go the EINVAL route, and I will commit the patch > > you did to > > add that. > > thanks. :) i've checked what posix sais about this and since it doesn't know > MAP_ANON there's no real rule for this case. the only thing that comes close > is: > > "The mmap() function may fail if: > > [EINVAL] > The addr argument (if MAP_FIXED was specified) or off is not a multiple of the > page size as returned by sysconf(), or is considered invalid by the > implementation." Yes, the 'considered invalid by the implementation' is the bit I'm claiming. -- John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201003221606.10924.jhb>