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document the randomized array in the quarantine

pull/50/merge
Daniel Micay 2018-10-12 15:10:35 -04:00
parent 6669166fe9
commit 0a64c7d6a1
1 changed files with 6 additions and 3 deletions
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@ -135,9 +135,12 @@ allocation and then unmapped on free.
* Slab allocations are zeroed on free
* Large allocations are purged and memory protected on free with the memory
mapping kept reserved in a quarantine to detect use-after-free
* The quarantine is a FIFO ring buffer, with the oldest mapping in the
quarantine being unmapped to make room for the most recently freed
mapping
* The quarantine is primarily based on a FIFO ring buffer, with the oldest
mapping in the quarantine being unmapped to make room for the most
recently freed mapping
* Another layer of the quarantine swaps with a random slot in an array to
randomize the number of large deallocations required to push mappings out
of the quarantine
* Detection of write-after-free by verifying zero filling is intact
* Memory in fresh allocations is consistently zeroed due to it either being
fresh pages or zeroed on free after previous usage