From: Jakub Jelinek <jakub@redhat.com>
To: Marco Elver <elver@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
Masahiro Yamada <masahiroy@kernel.org>,
Nathan Chancellor <nathan@kernel.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Nicolas Schier <nicolas@fjasle.eu>,
Andrey Ryabinin <ryabinin.a.a@gmail.com>,
Alexander Potapenko <glider@google.com>,
Andrey Konovalov <andreyknvl@gmail.com>,
Dmitry Vyukov <dvyukov@google.com>,
Vincenzo Frascino <vincenzo.frascino@arm.com>,
linux-kbuild@vger.kernel.org, kasan-dev@googlegroups.com,
linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
Tony Lindgren <tony@atomide.com>,
Ulf Hansson <ulf.hansson@linaro.org>,
linux-toolchains@vger.kernel.org
Subject: Re: [PATCH -tip] kasan: Emit different calls for instrumentable memintrinsics
Date: Fri, 10 Feb 2023 20:25:00 +0100 [thread overview]
Message-ID: <Y+aaDP32wrsd8GZq@tucnak> (raw)
In-Reply-To: <20230208184203.2260394-1-elver@google.com>
On Wed, Feb 08, 2023 at 07:42:03PM +0100, Marco Elver wrote:
> Clang 15 will provide an option to prefix calls to memcpy/memset/memmove
> with __asan_ in instrumented functions: https://reviews.llvm.org/D122724
>
> GCC does not yet have similar support.
GCC has support to rename memcpy/memset etc. for years, say on
following compiled with
-fsanitize=kernel-address -O2 -mstringop-strategy=libcall
(the last option just to make sure the compiler doesn't prefer to emit
rep mov*/stos* or loop or something similar, of course kernel can keep
whatever it uses) you'll get just __asan_memcpy/__asan_memset calls,
no memcpy/memset, while without -fsanitize=kernel-address you get
normally memcpy/memset.
Or do you need the __asan_* functions only in asan instrumented functions
and normal ones in non-instrumented functions in the same TU?
#ifdef __SANITIZE_ADDRESS__
extern __typeof (__builtin_memcpy) memcpy __asm ("__asan_memcpy");
extern __typeof (__builtin_memset) memset __asm ("__asan_memset");
#endif
struct S { char a[2048]; } a, b;
void
foo (void)
{
a = b;
b = (struct S) {};
}
void
bar (void *p, void *q, int s)
{
memcpy (p, q, s);
}
void
baz (void *p, int c, int s)
{
memset (p, c, s);
}
void
qux (void *p, void *q, int s)
{
__builtin_memcpy (p, q, s);
}
void
quux (void *p, int c, int s)
{
__builtin_memset (p, c, s);
}
Jakub
next prev parent reply other threads:[~2023-02-10 19:25 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-08 18:42 [PATCH -tip] kasan: Emit different calls for instrumentable memintrinsics Marco Elver
2023-02-09 22:43 ` Andrey Konovalov
2023-02-09 23:34 ` Marco Elver
2023-02-10 16:13 ` Andrey Konovalov
2023-02-10 18:40 ` Marco Elver
2023-02-10 21:36 ` Andrey Konovalov
2023-02-13 7:00 ` Marco Elver
2023-02-10 19:25 ` Jakub Jelinek [this message]
2023-02-10 20:07 ` Marco Elver
2023-02-13 11:01 ` Jakub Jelinek
2023-02-13 12:35 ` Peter Zijlstra
2023-02-13 13:37 ` Marco Elver
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y+aaDP32wrsd8GZq@tucnak \
--to=jakub@redhat.com \
--cc=andreyknvl@gmail.com \
--cc=dvyukov@google.com \
--cc=elver@google.com \
--cc=glider@google.com \
--cc=kasan-dev@googlegroups.com \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-toolchains@vger.kernel.org \
--cc=masahiroy@kernel.org \
--cc=mingo@kernel.org \
--cc=nathan@kernel.org \
--cc=ndesaulniers@google.com \
--cc=nicolas@fjasle.eu \
--cc=peterz@infradead.org \
--cc=ryabinin.a.a@gmail.com \
--cc=tony@atomide.com \
--cc=ulf.hansson@linaro.org \
--cc=vincenzo.frascino@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).