On Thu, 2017-02-09 at 20:52 +0200, Tanu Kaskinen wrote: > On Wed, 2017-02-08 at 10:06 -0300, Felipe Sateler wrote: > > On 8 February 2017 at 09:36, Tanu Kaskinen <tanuk at iki.fi> wrote: > > > On Fri, 2017-02-03 at 10:17 -0300, Felipe Sateler wrote: > > > > On 3 February 2017 at 05:51, Tanu Kaskinen <tanuk at iki.fi> wrote: > > > > > We disallow autospawning for root, but when using systemd socket > > > > > activation to start pulseaudio, that replaces the autospawning > > > > > mechanism, and there was no similar "root protection" in socket > > > > > activation. This patch disables the socket activation for root. > > > > > > > > > > Thanks to Felipe Sateler for coming up with the idea of using > > > > > ConditionPathIsReadWrite=!/run. > > > > > > > > I'm sorry but I'll have to take this back. This check only checks if > > > > the path is mounted read-write, not if the calling process has the > > > > necessary permissions. > > > > > > > > https://github.com/systemd/systemd/blob/master/src/shared/condition.c#L405 > > > > https://github.com/systemd/systemd/blob/master/src/basic/stat-util.c#L126 > > > > > > > > :( > > > > > > Well, that's disappointing (and shame on me - I should have tested the > > > patch better). > > > > > > I think using ExecStartPre as Ahmed first suggested is the best > > > solution. It should do exactly what we want. The admin capability check > > > can have some corner cases where it does the wrong thing. > > > > The ExecStartPre= solution has the undesirable side effect that it > > marks the unit as failed, and thus the systemd --user session as > > degraded. I think the CAP_SYS_ADMIN solution is a bit better until we > > get ConditionUID. Presumably the people running containers where root > > does not have CAP_SYS_ADMIN know what they are doing. > > Good point. I'll make v2 with the capability check. It turns out that the capability check doesn't work either. I don't have any idea why. "systemctl --user start pulseaudio.socket" doesn't indicate any failure, but it doesn't matter if I'm root (via "machinectl shell") or a regular user, "systemctl --user status pulseaudio.socket" prints the following: â?? pulseaudio.socket - Sound System    Loaded: loaded (/usr/lib/systemd/user/pulseaudio.socket; disabled; vendor preset: enabled)    Active: inactive (dead) Condition: start condition failed at Thu 2017-02-09 21:17:42 EET; 8min ago            â??â?? ConditionCapability=!CAP_SYS_ADMIN was not met    Listen: /run/user/1000/pulse/native (Stream) I submitted a bug report: https://github.com/systemd/systemd/issues/5296 I guess the last remaining solution is to use ExecStartPre. -- Tanu https://www.patreon.com/tanuk
