On Tue, Aug 25, 2020 at 12:48:04PM -0400, Peilin Ye wrote: > Hi all, > > Link: https://syzkaller.appspot.com/bug?id=f332576321998d36cd07d09c9c1268cfed1895c9 > > As reported by syzbot, vcs_read_buf() is overflowing `con_buf16`, since > this patch removed the following check: > > - if (count > CON_BUF_SIZE) { > - count = CON_BUF_SIZE; > - filled = count - pos; > - } > > Decreasing `count` by `min(HEADER_SIZE - pos, count)` bypasses this check. > Additionally, this patch also removed updates to `skip` and `filled`. > > What should we do in order to fix it? This patch is already reverted, and it has been discussed a bit as to how to do this properly if you look at the email where this was reported to us. thanks, greg k-h
