pkcs11: bound the config file index in pkcs11_config_load_objects()

[learnrahulrai-ui]

updateConfFileData[MAX_CONF_FILES] is indexed by i, which nothing bounds — MAX_CONF_FILES appears only in its #define and that declaration, never in a comparison.

Under AddressSanitizer at d49c7d5, varying only the number of .conf files in the filestore:

15 files   ok
16 files   stack-buffer-overflow READ  of size 8 at :1114
17 files   stack-buffer-overflow WRITE of size 8 at :1083

Two defects, not one. At 17 the store writes past the end. At 16 nothing is written out of bounds — the array is merely full, so the NULL that the parse walk and the free walk rely on as a terminator no longer exists. Bounding the store alone leaves 16 broken, so both walks are bounded by totalConfFileCount too.

16 is a normal configuration, not a crafted one: a slot with N objects is 1 + N files (0.conf plus 0.<handle>.conf), so the default PKCS11_MAX_OBJECTS_ALLOWED=16 needs 17.

i++ also moves inside the allocation-success branch, so i and totalConfFileCount cannot diverge; on a failed malloc the old code left a NULL hole that truncates one consumer loop and is dereferenced by the other.

To reproduce: put 0.conf and 0.2.conf … 0.17.conf in a filestore and call C_Initialize() on a build with -fsanitize=address.

Open question: MAX_CONF_FILES is PKCS11_MAX_SLOTS_ALLOWED * PKCS11_MAX_OBJECTS_ALLOWED, counting neither the per-slot base file nor the NULL these loops need. Resizing it changes stack usage on embedded targets, so this patch only bounds the index — happy to follow up with the resize if you would prefer that.

Checklist

• I have reviewed the CONTRIBUTING.md and agree to it's terms