On 5/1/24 2:50 AM, Hillf Danton wrote: > On Wed, 1 May 2024 02:01:20 -0400 Michael S. Tsirkin <[email protected]> >> >> and then it failed testing. >> > So did my patch [1] but then the reason was spotted [2,3] > > [1] https://lore.kernel.org/lkml/[email protected]/ > [2] https://lore.kernel.org/lkml/[email protected]/ > [3] https://lore.kernel.org/lkml/[email protected]/
Just to make sure I understand the conclusion. Edward's patch that just swaps the order of the calls: https://lore.kernel.org/lkml/[email protected]/ fixes the UAF. I tested the same in my setup. However, when you guys tested it with sysbot, it also triggered a softirq/RCU warning. The softirq/RCU part of the issue is fixed with this commit: https://lore.kernel.org/all/[email protected]/ commit 1dd1eff161bd55968d3d46bc36def62d71fb4785 Author: Zqiang <[email protected]> Date: Sat Apr 27 18:28:08 2024 +0800 softirq: Fix suspicious RCU usage in __do_softirq() The problem was that I was testing with -next master which has that patch. It looks like you guys were testing against bb7a2467e6be which didn't have the patch, and so that's why you guys still hit the softirq/RCU issue. Later when you added that patch to your patch, it worked with syzbot. So is it safe to assume that the softirq/RCU patch above will be upstream when the vhost changes go in or is there a tag I need to add to my patches?
