Fix heap bins tcache from accessing invalid addresses on glibc 2.42 #1197
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Description
Fix for heap bins tcache accessing invalid addresses on glibc 2.42.
Also adding a sanity check to ensure only properly aligned tcache entry pointers are traversed.
With the current implementation, when parsing tcache bins, corrupted values in the entry array (e.g. 0x7000…) can be misinterpreted as valid pointers. This causes gdb to dereference invalid memory and the command fails.
The fix adds a simple ptrsize-alignment check before constructing a GlibcTcacheChunk.
Since real heap chunk pointers are always ptrsize-aligned, this prevents mis-parsing and avoids invalid memory accesses without affecting normal behavior.
Checklist