linux-kernel - Re: [PATCH] arm64: CONFIG_DEVPORT should not be used when PCI is being used

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <201604090421.06414.arnd@arndb.de>
Date:	Sat, 9 Apr 2016 04:21:06 +0200
From:	Arnd Bergmann <arnd@...db.de>
To:	ahs3@...hat.com
Cc:	Geert Uytterhoeven <geert@...ux-m68k.org>,
	"Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] arm64: CONFIG_DEVPORT should not be used when PCI is being used

On Thursday 07 April 2016, Al Stone wrote:
> >>>  config DEVPORT
> >>>       bool
> >>> -     depends on !M68K
> >>> +     depends on !M68K && !ARM64
> >>
> >> Why not fix the real bug here, it's odd that only these two arches need
> >> this disabled, don't you agree?
> 
> Agreed.  It does seem odd.  I'm not sure I understand which bug you're thinking
> is the real one, though -- that DEVPORT should be disabled in all places that
> don't have ISA or that arm64 needs to have /dev/port work properly?  Or perhaps
> I missed something else entirely...

We've had a similar problem recently with ISA drivers crashing when no PCI
host registers itself for the first 0x1000 I/O port addresses.

I think both the request_resource() function and /dev/ioport should be
changed to interface with the dynamic registration of I/O port ranges
so they only ever allow access on ports that are mapped into virtual memory.

	Arnd