From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60065) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1exwjD-0006Yy-Kk for qemu-devel@nongnu.org; Mon, 19 Mar 2018 11:29:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1exwjC-0007Fh-Hi for qemu-devel@nongnu.org; Mon, 19 Mar 2018 11:29:39 -0400 Date: Mon, 19 Mar 2018 16:29:32 +0100 From: Kevin Wolf Message-ID: <20180319152932.GD30864@localhost.localdomain> References: <20180119224735.12169-1-jsnow@redhat.com> <086ccaa6-eefb-47e4-a865-78075ddd827d@redhat.com> <56b7204f-a0d8-3a4e-6e48-6913b1f52a5f@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <56b7204f-a0d8-3a4e-6e48-6913b1f52a5f@redhat.com> Subject: Re: [Qemu-devel] [PATCH v4] file-posix: specify expected filetypes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Snow Cc: Eric Blake , qemu-block@nongnu.org, qemu-devel@nongnu.org Am 13.03.2018 um 18:20 hat John Snow geschrieben: > > > On 01/19/2018 06:03 PM, Eric Blake wrote: > > On 01/19/2018 04:47 PM, John Snow wrote: > >> Adjust each caller of raw_open_common to specify if they are expecting > >> host and character devices or not. Tighten expectations of file types upon > >> open in the common code and refuse types that are not expected. > >> > >> This has two effects: > >> > >> (1) Character and block devices are now considered deprecated for the > >> 'file' driver, which expects only S_IFREG, and > >> (2) no file-posix driver (file, host_cdrom, or host_device) can open > >> directories now. > >> > >> I don't think there's a legitimate reason to open directories as if > >> they were files. This prevents QEMU from opening and attempting to probe > >> a directory inode, which can break in exciting ways. One of those ways > >> is lseek on ext4/xfs, which will return 0x7fffffffffffffff as the file > >> size instead of EISDIR. This can coax QEMU into responding with a > >> confusing "file too big" instead of "Hey, that's not a file". > >> > >> See: https://bugs.launchpad.net/qemu/+bug/1739304/ > >> Signed-off-by: John Snow > >> --- > > > > Reviewed-by: Eric Blake > > Whoops, I let this one rot. It could still be considered a bugfix for > next week. Yes, we should take this as a bugfix. Needs a rebase, though. Kevin