[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <87furxgclm.fsf@rasmusvillemoes.dk>
Date: Wed, 29 Jun 2016 00:41:57 +0200
From: Rasmus Villemoes <linux@...musvillemoes.dk>
To: pageexec@...email.hu
Cc: Emese Revfy <re.emese@...il.com>, kernel-hardening@...ts.openwall.com, spender@...ecurity.net, mmarek@...e.com, keescook@...omium.org, linux-kernel@...r.kernel.org, yamada.masahiro@...ionext.com, linux-kbuild@...r.kernel.org, minipli@...linux.so, linux@...linux.org.uk, catalin.marinas@....com, david.brown@...aro.org, benh@...nel.crashing.org, tglx@...utronix.de, akpm@...ux-foundation.org, jlayton@...chiereds.net, arnd@...db.de
Subject: Re: [PATCH v1 2/2] Mark functions with the __nocapture attribute
On Tue, Jun 28 2016, "PaX Team" <pageexec@...email.hu> wrote:
> On 28 Jun 2016 at 22:50, Rasmus Villemoes wrote:
>
>> > +extern const char *kstrdup_const(const char *s, gfp_t gfp) __nocapture(1);
>>
>> OK, so this one is pretty dangerous, and probably wrong. If one does
>>
>> foo->bar = kstrdup_const(a-macro-that-might-be-a-string-literal)
>>
>> in an .init function, foo->bar will very likely become dangling.
>
> doesn't kstrdup_const omit the copy only for arguments that are stored in
> .rodata (which doesn't include .init.rodata* and other init sections)?
>
Ah, right. But that's a little subtle. Also, it kind of defeats the
purpose of kstrdup_const - but it's probably not actually called with a
string literal all that often.
In any case, I think there's still a problem with strchr() and friends.
Rasmus
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.
