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Date:   Mon, 4 Jan 2021 15:33:33 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Nathan Chancellor <natechancellor@gmail.com>
Cc:     Marco Elver <elver@google.com>, Arnd Bergmann <arnd@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Nick Desaulniers <ndesaulniers@google.com>,
        George Popescu <georgepope@android.com>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        LKML <linux-kernel@vger.kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>
Subject: Re: [PATCH] ubsan: disable unsigned-integer-overflow sanitizer with
 clang
Message-Id: <20210104153333.4b6c7ae49edc4182d53bd17f@linux-foundation.org>
In-Reply-To: <20210104223336.GA2562866@ubuntu-m3-large-x86>
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        <CANpmjNNGmbgg_pFMC6X_6vZcj53jy7PsNyZAC88rOQC5zrOiFw@mail.gmail.com>
        <20210104223336.GA2562866@ubuntu-m3-large-x86>
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On Mon, 4 Jan 2021 15:33:36 -0700 Nathan Chancellor <natechancellor@gmail.com> wrote:

> > > +++ b/lib/Kconfig.ubsan
> > > @@ -122,6 +122,8 @@ config UBSAN_SIGNED_OVERFLOW
> > >
> > >  config UBSAN_UNSIGNED_OVERFLOW
> > >         bool "Perform checking for unsigned arithmetic overflow"
> > > +       # clang hugely expands stack usage with -fsanitize=object-size
> > 
> > This is the first time -fsanitize=object-size is mentioned. Typo?
> 
> Copy and paste issue from CONFIG_UBSAN_OBJECT_SIZE

This?

--- a/lib/Kconfig.ubsan~ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang-fix
+++ a/lib/Kconfig.ubsan
@@ -122,7 +122,7 @@ config UBSAN_SIGNED_OVERFLOW
 
 config UBSAN_UNSIGNED_OVERFLOW
 	bool "Perform checking for unsigned arithmetic overflow"
-	# clang hugely expands stack usage with -fsanitize=object-size
+	# clang hugely expands stack usage with -fsanitize=unsigned-integer-overflow
 	depends on !CC_IS_CLANG
 	depends on $(cc-option,-fsanitize=unsigned-integer-overflow)
 	help
_