27.01.2025 12:10, Ondrej Mosnacek пишет:
Hello, It looks like the commit in $SUBJ may have introduced an unintended change in behavior. According to the commit message, the intent was to require just one of {user, group} to match instead of both, which sounds reasonable, but the commit also changes the behavior for when neither of tun->owner and tun->group is set. Before the commit the access was always allowed, while after the commit CAP_NET_ADMIN is required in this case. I'm asking because the tun_tap subtest of selinux-testuite [1] started to fail after this commit (it assumed CAP_NET_ADMIN was not needed), so I'm trying to figure out if we need to change the test or if it needs to be fixed in the kernel. Thanks, [1] https://github.com/SELinuxProject/selinux-testsuite/
Hi, IMHO having the persistent TAP device inaccessible by anyone but the CAP_NET_ADMIN is rather useless, so the compatibility should be restored on the kernel side. I'd raise the questions about adding the CAP_NET_ADMIN checks into TUNSETOWNER and/or TUNSETPERSIST, but this particular change to TUNSETIFF, at least on my side, was unintentional. Sorry about that. :(