[Toybox] mkpasswd crashes in github ci

[Rob Landley]

On 6/25/25 09:19, enh wrote:
> On Tue, Jun 24, 2025 at 6:37 PM Rob Landley <rob at landley.net> wrote:
>>
>> On 6/6/25 23:05, Rob Landley wrote:
>>> On 6/5/25 08:51, enh wrote:
>>>> doesn't affect android's build because we don't build mkpasswd, but
>>>> the mkpasswd tests are failing on github with sigsegv:
>>>
>>> Sigh, the updated the ASAN plumbing, didn't they?
>>>
>>> https://landley.net/notes-2024.html#04-07-2024
>>>
>>> When you enable ASAN on current gcc toolchains, crypt() drops out and
>>> becomes a NULL pointer dereference. I don't know why. I need to put a
>>> crypt() implementation in lib/hash.c.
>>>
>>> If you disable ASAN, the tests pass just fine. ASAN is what breaks them.
>>
>> If I append this to lib/hash.c:
>>
>> char *krypt(char *phrase, char *setting)
>> {
>>     return "boom";
>> }
>> extern __typeof(crypt) crypt __attribute__((__weak__, __alias__("krypt")));
>>
>> Doing "ASAN=1 make clean mkpasswd; ./mkpasswd blah" STILL fails with the
>> exact same null pointer dereference.
>>
>> I dunno what gcc's ASAN is doing, but it appears to be failing at
>> runtime, not link time. I presumably need a compile time probe in
>> scripts/genconfig.sh to detect crypt() failing and swap it out with a
>> config symbol and #ifdefs, which is just sad...
>>
>> Maybe I should just switch the github test to "make toybox tests" which
>> will build a toybox binary without ASAN and then test the existing
>> binary? (The test builds enable ASAN, but make tests will use the
>> existing binary if there is one, so listing both tests without asan...)
> 
> or just use clang for asan? probably good to have both clang and gcc
> in ci anyway, since you support both...

ASAN doesn't work static linked, and I build static bionic binaries to 
avoid manually installing stuff outside of my home dir and /usr/local so 
running the dynamic binaries would require a chroot and sudo (thus not 
something the test suite could do normally).

I suppose I could try building clang glibc binaries for ASAN testing...

Rob