On Wed, Dec 27, 2023 at 12:58 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Wed, 27 Dec 2023 14:11:06 +0800 Chengming Zhou <zhouchengming@xxxxxxxxxxxxx> wrote: > > > > i remember there was an over-compression case, that means the compressed > > > data can be bigger than the source data. the similar thing is also done in zram > > > drivers/block/zram/zcomp.c > > > > Right, there is a buffer overflow report[1] that I just +to you. > > What does "[1]" refer to? Is there a bug report about this series? I think Chengming was referring to this: https://lore.kernel.org/lkml/0000000000000b05cd060d6b5511@xxxxxxxxxx/ Syzkaller/syzbot found an edge case where the page's "compressed" form was larger than one page, which tripped up the compression code (since we reduced the compression buffer size to 1 page here).
