[PATCH] ARM: ubsan: select ARCH_HAS_UBSAN_SANITIZE_ALL

[Florian Fainelli]

On 9/29/22 01:10, Kees Cook wrote:
> On Wed, Sep 28, 2022 at 05:33:14PM -0700, William Zhang wrote:
>>
>>
>> On 09/28/2022 04:06 PM, Florian Fainelli wrote:
>>> On 9/28/22 11:01, Kees Cook wrote:
>>>> On Wed, Sep 28, 2022 at 10:47:39AM -0700, Florian Fainelli wrote:
>>>>> From: Seung-Woo Kim <sw0312.kim at samsung.com>
>>>>>
>>>>> To enable UBSAN on ARM, this patch enables ARCH_HAS_UBSAN_SANITIZE_ALL
>>>>> from arm confiuration. Basic kernel bootup test is passed on arm with
>>>>> CONFIG_UBSAN_SANITIZE_ALL enabled.
>>>>>
>>>>> Signed-off-by: Seung-Woo Kim <sw0312.kim at samsung.com>
>>>>> [florian: rebased against v6.0-rc7]
>>>>> Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
>>>>
>>>> Ah-ha, thanks for testing this. What devices did you check this on? I
>>>> know boot-up on arm32 can be very device-specific.
>>>
>>> This was tested on an ARCH_BRCMSTB system which is using an ARMv8 CPU
>>> booted in AArch32 mode, so virtually equivalent to armv7l. A raspberry
>>> Pi 4B is also happily booting with it.
>>>
>>>>
>>>> Which UBSAN configs did you try?
>>>
>>> All CONFIG_UBSAN_* work with the exception of CONFIG_UBSAN_ALIGNMENT on
>>> my ARCH_BRCMSTB system, however it works fine on the Raspberry Pi 4B.
>>> Florian
>>
>> I also tested on a BCM63138 board (ARM A9) under ARCH_BCMBCA using the
>> multi_v7_defconfig with all the UBSAN configs enabled except UBSAN_ALIGNMENT
>> and board boots up fine. Turning on UBSAN_ALIGNMENT results in flood of
>> false positive misaligned-access warnings. This is fine as ARM supports
>> unaligned access.
>>
>> It did catch an out-of-band bug in mach-sunxi smp code.  I will submit a
>> separate patch to fix that bug.
> 
> Yay! :) Move coverage is great. :)
> 
>>
>> Tested-by: William Zhang <william.zhang at broadcom.com>

Submitted to the patch tracker:

https://www.armlinux.org.uk/developer/patches/viewpatch.php?id=9253/1
-- 
Florian