Re: [folded-merged] ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang-fix.patch removed from -mm tree

From: Kees Cook <keescook@chromium.org>
To: akpm@linux-foundation.org
Cc: arnd@arndb.de, elver@google.com, georgepope@android.com,
	mm-commits@vger.kernel.org, natechancellor@gmail.com,
	ndesaulniers@google.com, sfr@canb.auug.org.au
Subject: Re: [folded-merged] ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang-fix.patch removed from -mm tree
Date: Thu, 7 Jan 2021 13:09:29 -0800	[thread overview]
Message-ID: <202101071308.8854B1428B@keescook> (raw)
In-Reply-To: <20210107003426.Bqzd_O7Lf%akpm@linux-foundation.org>

On Wed, Jan 06, 2021 at 04:34:26PM -0800, akpm@linux-foundation.org wrote:
> 
> The patch titled
>      Subject: ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang-fix
> has been removed from the -mm tree.  Its filename was
>      ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang-fix.patch
> 
> This patch was dropped because it was folded into ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang.patch
> 
> ------------------------------------------------------
> From: Andrew Morton <akpm@linux-foundation.org>
> Subject: ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang-fix
> 
> fix comment typo, per Nathan
> 
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: George Popescu <georgepope@android.com>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Marco Elver <elver@google.com>
> Cc: Nathan Chancellor <natechancellor@gmail.com>
> Cc: Nick Desaulniers <ndesaulniers@google.com>
> Cc: Stephen Rothwell <sfr@canb.auug.org.au>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
> 
>  lib/Kconfig.ubsan |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- 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

The above "!CC_IS_CLANG" needs to be dropped. I makes it impossible to use at
all (unsigned UBSAN overflow is only implemented for Clang).

-Kees

>  	depends on $(cc-option,-fsanitize=unsigned-integer-overflow)
>  	help
> _
> 
> Patches currently in -mm which might be from akpm@linux-foundation.org are
> 
> mm-page_alloc-add-a-missing-mm_page_alloc_zone_locked-tracepoint-fix.patch
> ubsan-disable-unsigned-integer-overflow-sanitizer-with-clang.patch
> mm.patch
> mm-memcg-slab-pre-allocate-obj_cgroups-for-slab-caches-with-slab_account-fix.patch
> mm-memcontrol-optimize-per-lruvec-stats-counter-memory-usage-checkpatch-fixes.patch
> kasan-fix-bug-detection-via-ksize-for-hw_tags-mode-fix.patch
> mm-cma-allocate-cma-areas-bottom-up-fix-3-fix.patch
> mm-vmstat-fix-proc-sys-vm-stat_refresh-generating-false-warnings-fix-2.patch
> kfence-kasan-make-kfence-compatible-with-kasan-fix.patch
> set_memory-allow-set_direct_map__noflush-for-multiple-pages-fix.patch
> arch-mm-wire-up-memfd_secret-system-call-were-relevant-fix.patch
> kernel-forkc-export-kernel_thread-to-modules.patch
> 

-- 
Kees Cook