user/sven/linux.git/include/linux/utsname.h, branch v3.0.85

userns: allow sethostname in a container

2011-03-24T02:47:03Z

Changelog: Feb 23: let clone_uts_ns() handle setting uts->user_ns To do so we need to pass in the task_struct who'll get the utsname, so we can get its user_ns. Feb 23: As per Oleg's coment, just pass in tsk, instead of two of its members. Signed-off-by: Serge E. Hallyn Acked-by: "Eric W. Biederman" Acked-by: Daniel Lezcano Acked-by: David Howells Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

userns: add a user_namespace as creator/owner of uts_namespace

2011-03-24T02:46:59Z

The expected course of development for user namespaces targeted capabilities is laid out at https://wiki.ubuntu.com/UserNamespace. Goals: - Make it safe for an unprivileged user to unshare namespaces. They will be privileged with respect to the new namespace, but this should only include resources which the unprivileged user already owns. - Provide separate limits and accounting for userids in different namespaces. Status: Currently (as of 2.6.38) you can clone with the CLONE_NEWUSER flag to get a new user namespace if you have the CAP_SYS_ADMIN, CAP_SETUID, and CAP_SETGID capabilities. What this gets you is a whole new set of userids, meaning that user 500 will have a different 'struct user' in your namespace than in other namespaces. So any accounting information stored in struct user will be unique to your namespace. However, throughout the kernel there are checks which - simply check for a capability. Since root in a child namespace has all capabilities, this means that a child namespace is not constrained. - simply compare uid1 == uid2. Since these are the integer uids, uid 500 in namespace 1 will be said to be equal to uid 500 in namespace 2. As a result, the lxc implementation at lxc.sf.net does not use user namespaces. This is actually helpful because it leaves us free to develop user namespaces in such a way that, for some time, user namespaces may be unuseful. Bugs aside, this patchset is supposed to not at all affect systems which are not actively using user namespaces, and only restrict what tasks in child user namespace can do. They begin to limit privilege to a user namespace, so that root in a container cannot kill or ptrace tasks in the parent user namespace, and can only get world access rights to files. Since all files currently belong to the initila user namespace, that means that child user namespaces can only get world access rights to *all* files. While this temporarily makes user namespaces bad for system containers, it starts to get useful for some sandboxing. I've run the 'runltplite.sh' with and without this patchset and found no difference. This patch: copy_process() handles CLONE_NEWUSER before the rest of the namespaces. So in the case of clone(CLONE_NEWUSER|CLONE_NEWUTS) the new uts namespace will have the new user namespace as its owner. That is what we want, since we want root in that new userns to be able to have privilege over it. Changelog: Feb 15: don't set uts_ns->user_ns if we didn't create a new uts_ns. Feb 23: Move extern init_user_ns declaration from init/version.c to utsname.h. Signed-off-by: Serge E. Hallyn Acked-by: "Eric W. Biederman" Acked-by: Daniel Lezcano Acked-by: David Howells Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

headers: utsname.h redux

2009-09-24T01:13:10Z

* remove asm/atomic.h inclusion from linux/utsname.h -- not needed after kref conversion * remove linux/utsname.h inclusion from files which do not need it NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however due to some personality stuff it _is_ needed -- cowardly leave ELF-related headers and files alone. Signed-off-by: Alexey Dobriyan Signed-off-by: Linus Torvalds

utsname.h: make new_utsname fields use the proper length constant

2009-06-17T02:47:47Z

The members of the new_utsname structure are defined with magic numbers that *should* correspond to the constant __NEW_UTS_LEN+1. Everywhere else, code assumes this and uses the constant, so this patch makes the structure match. Originally suggested by Serge here: https://lists.linux-foundation.org/pipermail/containers/2009-March/016258.html Signed-off-by: Dan Smith Acked-by: Serge Hallyn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

namespaces: move the UTS namespace under UTS_NS option

2008-02-08T17:22:23Z

Currently all the namespace management code is in the kernel/utsname.c file, so just compile it out and make stubs in the appropriate header. The init namespace itself is in init/version.c and is in the kernel all the time. Signed-off-by: Pavel Emelyanov Acked-by: Serge Hallyn Cc: Cedric Le Goater Cc: "Eric W. Biederman" Cc: Herbert Poetzl Cc: Kirill Korotaev Cc: Sukadev Bhattiprolu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

namespace: ensure clone_flags are always stored in an unsigned long

2007-07-16T16:05:48Z

While working on unshare support for the network namespace I noticed we were putting clone flags in an int. Which is weird because the syscall uses unsigned long and we at least need an unsigned to properly hold all of the unshare flags. So to make the code consistent, this patch updates the code to use unsigned long instead of int for the clone flags in those places where we get it wrong today. Signed-off-by: Eric W. Biederman Acked-by: Cedric Le Goater Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

remove CONFIG_UTS_NS and CONFIG_IPC_NS

2007-07-16T16:05:47Z

CONFIG_UTS_NS and CONFIG_IPC_NS have very little value as they only deactivate the unshare of the uts and ipc namespaces and do not improve performance. Signed-off-by: Cedric Le Goater Acked-by: "Serge E. Hallyn" Cc: Eric W. Biederman Cc: Herbert Poetzl Cc: Pavel Emelianov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge sys_clone()/sys_unshare() nsproxy and namespace handling

2007-05-08T18:15:00Z

sys_clone() and sys_unshare() both makes copies of nsproxy and its associated namespaces. But they have different code paths. This patch merges all the nsproxy and its associated namespace copy/clone handling (as much as possible). Posted on container list earlier for feedback. - Create a new nsproxy and its associated namespaces and pass it back to caller to attach it to right process. - Changed all copy_*_ns() routines to return a new copy of namespace instead of attaching it to task->nsproxy. - Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines. - Removed unnessary !ns checks from copy_*_ns() and added BUG_ON() just incase. - Get rid of all individual unshare_*_ns() routines and make use of copy_*_ns() instead. [akpm@osdl.org: cleanups, warning fix] [clg@fr.ibm.com: remove dup_namespaces() declaration] [serue@us.ibm.com: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval] [akpm@linux-foundation.org: fix build with CONFIG_SYSVIPC=n] Signed-off-by: Badari Pulavarty Signed-off-by: Serge Hallyn Cc: Cedric Le Goater Cc: "Eric W. Biederman" Cc: Signed-off-by: Cedric Le Goater Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] utsns: fix !CONFIG_UTS_NS behavior

2007-03-27T16:05:15Z

When CONFIG_UTS_NS=n, clone(CLONE_NEWUTS) quietly refuses. So correctly does not unshare a new uts namespace, but also does not return -EINVAL. Fix this to return -EINVAL so the caller knows his request was denied. Signed-off-by: Serge E. Hallyn Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] ipc: headers_check fix

2006-10-04T14:55:12Z

Fix headers_check #ifdef __KERNEL__ stuff. Signed-off-by: Cedric Le Goater All-the-fault-of: David Woodhouse Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds