On Tue, Jan 14, 2025 at 2:11 PM Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > > On 01/14, Andrii Nakryiko wrote: > > > > On Tue, Jan 14, 2025 at 12:40 PM Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > > > > > > But, unlike sys_uretprobe(), sys_rt_sigreturn() is old, so the existing > > > setups must know that sigreturn() should be respected... > > > > someday sys_uretprobe will be old as well ;) FWIW, systemd allowlisted > > sys_uretprobe, see [0] > > And I agree! ;) > > I mean, I'd personally prefer to do nothing and wait until userspace figures > out that we have another "special" syscall. > > But can we do it? I simply do not know. Can we ignore this (valid) bug report? > Seems wrong for kernel to try to guess whether some syscall is filtered by some policy or not (though maybe I'm misunderstanding the details and it's kernel-originated problem?). Seems like a recipe for more problems. Nothing is really fundamentally broken. Some piece of software needs an upgraded library to not disable the kernel's special syscall (just like sys_rt_sigreturn, nothing "new" here, really). Users can't do uprobing in such broken setups (but not in general), seems like a good incentive for everyone to push for the right thing here: fixed up to date software. > Oleg. >
