On Tue, 2019-08-06 at 13:43 +0800, Walter Wu wrote: > This patch adds memory corruption identification at bug report for > software tag-based mode, the report show whether it is "use-after-free" > or "out-of-bound" error instead of "invalid-access" error. This will make > it easier for programmers to see the memory corruption problem. > > We extend the slab to store five old free pointer tag and free backtrace, > we can check if the tagged address is in the slab record and make a > good guess if the object is more like "use-after-free" or "out-of-bound". > therefore every slab memory corruption can be identified whether it's > "use-after-free" or "out-of-bound". > > ====== Changes > Change since v1: > - add feature option CONFIG_KASAN_SW_TAGS_IDENTIFY. > - change QUARANTINE_FRACTION to reduce quarantine size. > - change the qlist order in order to find the newest object in quarantine > - reduce the number of calling kmalloc() from 2 to 1 time. > - remove global variable to use argument to pass it. > - correct the amount of qobject cache->size into the byes of qlist_head. > - only use kasan_cache_shrink() to shink memory. > > Change since v2: > - remove the shinking memory function kasan_cache_shrink() > - modify the description of the CONFIG_KASAN_SW_TAGS_IDENTIFY > - optimize the quarantine_find_object() and qobject_free() > - fix the duplicating function name 3 times in the header. > - modify the function name set_track() to kasan_set_track() > > Change since v3: > - change tag-based quarantine to extend slab to identify memory corruption Hi,Andrey, Would you review the patch,please? This patch is to pre-allocate slub record(tag and free backtrace) during create slub object. When kernel has memory corruption, it will print correct corruption type and free backtrace. Thanks. Walter
