Re: [PATCH] [RFC] ubsan: disallow bounds checking with gcov on broken gcc

Arnd Bergmann
2023-06-01T19:04:19Z

On Thu, Jun 1, 2023, at 20:28, Kees Cook wrote:
> On Thu, Jun 01, 2023 at 07:50:38PM +0200, Arnd Bergmann wrote:
>> On Thu, Jun 1, 2023, at 18:14, Kees Cook wrote:
>> >
>> > i.e. fall back through these:
>> > -fsanitize=array-bounds (Clang)
>> > -fsanitize=bounds-strict (!GCOV || bug fixed in GCC)
>> > -fsanitize=bounds
>>
>> From what I can tell, -fsanitize=bounds has the same problem
>> as -fsanitize=bounds-strict, so that would not help.
>
> Ah, did something change with GCOV? This (bounds vs bounds-strict) is
> the only recent change to CONFIG_UBSAN_BOUNDS...

I missed this problem in my usual randconfig builds because I was
building with GCOV disabled due to disk size limitations until
Dan Carpenter pointed out the specific issue.

I suspect it's been there for a longer time.

Arnd