Poison pages after freeing
modulename: page_poison.ko
configname: CONFIG_PAGE_POISONING
Linux Kernel Configuration
└─>Kernel hacking
└─>Memory Debugging
└─>Poison pages after freeing
In linux kernel since version 2.6.30 (release Date: 2009-06-09)
Fill the pages with poison patterns after free_pages() and verify
the patterns before alloc_pages. The filling of the memory helps
reduce the risk of information leaks from freed data. This does
have a potential performance impact if enabled with the
"page_poison=1" kernel boot option.
Note that "poison" here is not the same thing as the "HWPoison"
for CONFIG_MEMORY_FAILURE. This is software poisoning only.
If you are only interested in sanitization of freed pages without
checking the poison pattern on alloc, you can boot the kernel with
"init_on_free=1" instead of enabling this.
If unsure, say N
the patterns before alloc_pages. The filling of the memory helps
reduce the risk of information leaks from freed data. This does
have a potential performance impact if enabled with the
"page_poison=1" kernel boot option.
Note that "poison" here is not the same thing as the "HWPoison"
for CONFIG_MEMORY_FAILURE. This is software poisoning only.
If you are only interested in sanitization of freed pages without
checking the poison pattern on alloc, you can boot the kernel with
"init_on_free=1" instead of enabling this.
If unsure, say N