HashAllocator: poison freed blocks #366
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When the Click build is configured with the option --enable-hash-allocator-poisoning, this change will cause the HashAllocator to write a "poison" byte value to the block being returned to a HashAllocator pool. This ensures that when a stale reference to a freed block is followed, the code will be much less likely to interpret the block as a valid object or struct. In particular, pointer values will be non-NULL but bad, leading to immediate failure with a clear signature indicating the presence of a stale reference bug. Signed-off-by: Andy Heffernan <ahh@meraki.com>
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When the Click build is configured with the option
--enable-hash-allocator-poisoning, this change will cause
the HashAllocator to write a "poison" byte value to the block being
returned to a HashAllocator pool. This ensures that when a stale
reference to a freed block is followed, the code will be much less likely
to interpret the block as a valid object or struct. In particular,
pointer values will be non-NULL but bad, leading to immediate failure
with a clear signature indicating the presence of a stale reference bug.
Signed-off-by: Andy Heffernan ahh@meraki.com