|
Message-ID: <20170509085659.GA32555@infradead.org> Date: Tue, 9 May 2017 01:56:59 -0700 From: Christoph Hellwig <hch@...radead.org> To: Ingo Molnar <mingo@...nel.org> Cc: Greg KH <greg@...ah.com>, Thomas Garnier <thgarnie@...gle.com>, Martin Schwidefsky <schwidefsky@...ibm.com>, Heiko Carstens <heiko.carstens@...ibm.com>, Dave Hansen <dave.hansen@...el.com>, Arnd Bergmann <arnd@...db.de>, Thomas Gleixner <tglx@...utronix.de>, David Howells <dhowells@...hat.com>, René Nyffenegger <mail@...enyffenegger.ch>, Andrew Morton <akpm@...ux-foundation.org>, "Paul E . McKenney" <paulmck@...ux.vnet.ibm.com>, "Eric W . Biederman" <ebiederm@...ssion.com>, Oleg Nesterov <oleg@...hat.com>, Pavel Tikhomirov <ptikhomirov@...tuozzo.com>, Ingo Molnar <mingo@...hat.com>, "H . Peter Anvin" <hpa@...or.com>, Andy Lutomirski <luto@...nel.org>, Paolo Bonzini <pbonzini@...hat.com>, Rik van Riel <riel@...hat.com>, Kees Cook <keescook@...omium.org>, Josh Poimboeuf <jpoimboe@...hat.com>, Borislav Petkov <bp@...en8.de>, Brian Gerst <brgerst@...il.com>, "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>, Christian Borntraeger <borntraeger@...ibm.com>, Russell King <linux@...linux.org.uk>, Will Deacon <will.deacon@....com>, Catalin Marinas <catalin.marinas@....com>, Mark Rutland <mark.rutland@....com>, James Morse <james.morse@....com>, linux-s390 <linux-s390@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>, Linux API <linux-api@...r.kernel.org>, the arch/x86 maintainers <x86@...nel.org>, linux-arm-kernel@...ts.infradead.org, Kernel Hardening <kernel-hardening@...ts.openwall.com>, Linus Torvalds <torvalds@...ux-foundation.org>, Peter Zijlstra <a.p.zijlstra@...llo.nl> Subject: Re: Re: [PATCH v9 1/4] syscalls: Verify address limit before returning to user-mode On Tue, May 09, 2017 at 08:45:22AM +0200, Ingo Molnar wrote: > We only have ~115 code blocks in the kernel that set/restore KERNEL_DS, it would > be a pity to add a runtime check to every system call ... I think we should simply strive to remove all of them that aren't in core scheduler / arch code. Basically evetyytime we do the oldfs = get_fs(); set_fs(KERNEL_DS); .. set_fs(oldfs); trick we're doing something wrong, and there should always be better ways to archive it. E.g. using iov_iter with a ITER_KVEC type consistently would already remove most of them.
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.