Hi, On Sat, May 01, 2021 at 05:18:50PM -0700, Sargun Dhillon wrote: [snip] > Other patches in this series add a way to block signals when a syscall > is put to wait by seccomp. I guess we can drop this bit from the message if the series is split. > The struct seccomp_notif_resp, used when doing SECCOMP_IOCTL_NOTIF_SEND > ioctl() to send a response to the target, has three more fields that we > don't allow to set when doing the addfd ioctl() to also return. The > reasons to disallow each field are: > * val: This will be set to the new allocated fd. No point taking it > from userspace in this case. > * error: If this is non-zero, the value is ignored. Therefore, > it is pointless in this case as we want to return the value. > * flags: The only flag is to let userspace continue to execute the > syscall. This seems pointless, as we want the syscall to return the > allocated fd. > > This is why those fields are not possible to set when using this new > flag. I don't quite understand this; you don't need a NOTIF_SEND at all with the way this currently works, right? > @@ -1113,7 +1136,7 @@ static int seccomp_do_user_notification(int this_syscall, > struct seccomp_kaddfd, list); > /* Check if we were woken up by a addfd message */ > if (addfd) > - seccomp_handle_addfd(addfd); > + seccomp_handle_addfd(addfd, &n); > > } while (n.state != SECCOMP_NOTIFY_REPLIED); > This while() bit is introduced in the previous patch, can we fold this deletion into that somehow? Thanks, Tycho
