bad rss-counter state - bug

posted & found by zer0day

tl;dr

Found in LK v4.17.0+. Interesting oneā€¦ :)

Call Trace (Dump)

Got from syzkaller

...
[ 1251.494022] BUG: Bad rss-counter state mm:00000000bb7fc423 idx:0 val:8192
[ 1251.494998] BUG: Bad rss-counter state mm:00000000bb7fc423 idx:1 val:2
[ 1251.495890] BUG: non-zero pgtables_bytes on freeing mm: 73728
...

PoC

Skip!

End