So after spending some time debugging this issue and figuring it out I find that it's already been reported against quantal when quantal was not yet a 3.6.6. https://bugs.launchpad.net/ubuntu/+source/samba/+bug/1016895 I can confirm that my issue is a duplicate of that one.
There is already a good writeup on the samba side of the issue in the bug report but I can explain why it only happens on kernels 3.5 and higher here. Looking at the setgroups syscall code in kerne/groups.c shows that a major rewrite landed in 3.5 as part of the user namespace patches. One of the consequences of this is that the groups_from_user function, which is called by setgroups, now explicitly tests against a gid of -1. This is done because this value is now overloaded as INVALID_GID for use in the user namespace implementation to indicate that a gid has no mapping to the kernel namespace. Now that 3.5 is in precise and is planned to be made the default for the next point release I think it's important that the upstream cherrypick from bug 1016895 get included in samba 3.6.3 as soon as possible. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1075670 Title: samba panics with sys_setgroups failed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1075670/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
