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2019-12-05net/net_namespace: Check the return value of register_pernet_subsys()Aditya Pakki
[ Upstream commit 0eb987c874dc93f9c9d85a6465dbde20fdd3884c ] In net_ns_init(), register_pernet_subsys() could fail while registering network namespace subsystems. The fix checks the return value and sends a panic() on failure. Signed-off-by: Aditya Pakki <pakki001@umn.edu> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27netns: provide pure entropy for net_hash_mix()Eric Dumazet
[ Upstream commit 355b98553789b646ed97ad801a619ff898471b92 ] net_hash_mix() currently uses kernel address of a struct net, and is used in many places that could be used to reveal this address to a patient attacker, thus defeating KASLR, for the typical case (initial net namespace, &init_net is not dynamically allocated) I believe the original implementation tried to avoid spending too many cycles in this function, but security comes first. Also provide entropy regardless of CONFIG_NET_NS. Fixes: 0b4419162aa6 ("netns: introduce the net_hash_mix "salt" for hashes") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13net: move somaxconn init from sysctl codeRoman Kapl
[ Upstream commit 7c3f1875c66fbc19762760097cabc91849ea0bbb ] The default value for somaxconn is set in sysctl_core_net_init(), but this function is not called when kernel is configured without CONFIG_SYSCTL. This results in the kernel not being able to accept TCP connections, because the backlog has zero size. Usually, the user ends up with: "TCP: request_sock_TCP: Possible SYN flooding on port 7. Dropping request. Check SNMP counters." If SYN cookies are not enabled the connection is rejected. Before ef547f2ac16 (tcp: remove max_qlen_log), the effects were less severe, because the backlog was always at least eight slots long. Signed-off-by: Roman Kapl <roman.kapl@sysgo.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02net: Fix double free and memory corruption in get_net_ns_by_id()Eric W. Biederman
[ Upstream commit 21b5944350052d2583e82dd59b19a9ba94a007f0 ] (I can trivially verify that that idr_remove in cleanup_net happens after the network namespace count has dropped to zero --EWB) Function get_net_ns_by_id() does not check for net::count after it has found a peer in netns_ids idr. It may dereference a peer, after its count has already been finaly decremented. This leads to double free and memory corruption: put_net(peer) rtnl_lock() atomic_dec_and_test(&peer->count) [count=0] ... __put_net(peer) get_net_ns_by_id(net, id) spin_lock(&cleanup_list_lock) list_add(&net->cleanup_list, &cleanup_list) spin_unlock(&cleanup_list_lock) queue_work() peer = idr_find(&net->netns_ids, id) | get_net(peer) [count=1] | ... | (use after final put) v ... cleanup_net() ... spin_lock(&cleanup_list_lock) ... list_replace_init(&cleanup_list, ..) ... spin_unlock(&cleanup_list_lock) ... ... ... ... put_net(peer) ... atomic_dec_and_test(&peer->count) [count=0] ... spin_lock(&cleanup_list_lock) ... list_add(&net->cleanup_list, &cleanup_list) ... spin_unlock(&cleanup_list_lock) ... queue_work() ... rtnl_unlock() rtnl_lock() ... for_each_net(tmp) { ... id = __peernet2id(tmp, peer) ... spin_lock_irq(&tmp->nsid_lock) ... idr_remove(&tmp->netns_ids, id) ... ... ... net_drop_ns() ... net_free(peer) ... } ... | v cleanup_net() ... (Second free of peer) Also, put_net() on the right cpu may reorder with left's cpu list_replace_init(&cleanup_list, ..), and then cleanup_list will be corrupted. Since cleanup_net() is executed in worker thread, while put_net(peer) can happen everywhere, there should be enough time for concurrent get_net_ns_by_id() to pick the peer up, and the race does not seem to be unlikely. The patch fixes the problem in standard way. (Also, there is possible problem in peernet2id_alloc(), which requires check for net::count under nsid_lock and maybe_get_net(peer), but in current stable kernel it's used under rtnl_lock() and it has to be safe. Openswitch begun to use peernet2id_alloc(), and possibly it should be fixed too. While this is not in stable kernel yet, so I'll send a separate message to netdev@ later). Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Fixes: 0c7aecd4bde4 "netns: add rtnl cmd to add and get peer netns ids" Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-10net: check dead netns for peernet2id_alloc()WANG Cong
[ Upstream commit cfc44a4d147ea605d66ccb917cc24467d15ff867 ] Andrei reports we still allocate netns ID from idr after we destroy it in cleanup_net(). cleanup_net(): ... idr_destroy(&net->netns_ids); ... list_for_each_entry_reverse(ops, &pernet_list, list) ops_exit_list(ops, &net_exit_list); -> rollback_registered_many() -> rtmsg_ifinfo_build_skb() -> rtnl_fill_ifinfo() -> peernet2id_alloc() After that point we should not even access net->netns_ids, we should check the death of the current netns as early as we can in peernet2id_alloc(). For net-next we can consider to avoid sending rtmsg totally, it is a good optimization for netns teardown path. Fixes: 0c7aecd4bde4 ("netns: add rtnl cmd to add and get peer netns ids") Reported-by: Andrei Vagin <avagin@gmail.com> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-17netns: make nsid_lock per netWANG Cong
The spinlock is used to protect netns_ids which is per net, so there is no need to use a global spinlock. Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14netns: fix unbalanced spin_lock on errorNicolas Dichtel
Unlock was missing on error path. Fixes: 95f38411df05 ("netns: use a spin_lock to protect nsid management") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Four minor merge conflicts: 1) qca_spi.c renamed the local variable used for the SPI device from spi_device to spi, meanwhile the spi_set_drvdata() call got moved further up in the probe function. 2) Two changes were both adding new members to codel params structure, and thus we had overlapping changes to the initializer function. 3) 'net' was making a fix to sk_release_kernel() which is completely removed in 'net-next'. 4) In net_namespace.c, the rtnl_net_fill() call for GET operations had the command value fixed, meanwhile 'net-next' adjusted the argument signature a bit. This also matches example merge resolutions posted by Stephen Rothwell over the past two days. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-12netns: return RTM_NEWNSID instead of RTM_GETNSID on a getNicolas Dichtel
Usually, RTM_NEWxxx is returned on a get (same as a dump). Fixes: 0c7aecd4bde4 ("netns: add rtnl cmd to add and get peer netns ids") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09netlink: allow to listen "all" netnsNicolas Dichtel
More accurately, listen all netns that have a nsid assigned into the netns where the netlink socket is opened. For this purpose, a netlink socket option is added: NETLINK_LISTEN_ALL_NSID. When this option is set on a netlink socket, this socket will receive netlink notifications from all netns that have a nsid assigned into the netns where the socket has been opened. The nsid is sent to userland via an anscillary data. With this patch, a daemon needs only one socket to listen many netns. This is useful when the number of netns is high. Because 0 is a valid value for a nsid, the field nsid_is_set indicates if the field nsid is valid or not. skb->cb is initialized to 0 on skb allocation, thus we are sure that we will never send a nsid 0 by error to the userland. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09netns: use a spin_lock to protect nsid managementNicolas Dichtel
Before this patch, nsid were protected by the rtnl lock. The goal of this patch is to be able to find a nsid without needing to hold the rtnl lock. The next patch will introduce a netlink socket option to listen to all netns that have a nsid assigned into the netns where the socket is opened. Thus, it's important to call rtnl_net_notifyid() outside the spinlock, to avoid a recursive lock (nsid are notified via rtnl). This was the main reason of the previous patch. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09netns: notify new nsid outside __peernet2id()Nicolas Dichtel
There is no functional change with this patch. It will ease the refactoring of the locking system that protects nsids and the support of the netlink socket option NETLINK_LISTEN_ALL_NSID. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09netns: rename peernet2id() to peernet2id_alloc()Nicolas Dichtel
In a following commit, a new function will be introduced to only lookup for a nsid (no allocation if the nsid doesn't exist). To avoid confusion, the existing function is renamed. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09netns: always provide the id to rtnl_net_fill()Nicolas Dichtel
The goal of this commit is to prepare the rework of the locking of nsnid protection. After this patch, rtnl_net_notifyid() will not call anymore __peernet2id(), ie no idr_* operation into this function. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09netns: returns always an id in __peernet2id()Nicolas Dichtel
All callers of this function expect a nsid, not an error. Thus, returns NETNSA_NSID_NOT_ASSIGNED in case of error so that callers don't have to convert the error to NETNSA_NSID_NOT_ASSIGNED. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-16netns: remove duplicated include from net_namespace.cWei Yongjun
Remove duplicated include. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-07netns: allow to dump netns idsNicolas Dichtel
Which this patch, it's possible to dump the list of ids allocated for peer netns. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-07netns: notify netns id eventsNicolas Dichtel
With this patch, netns ids that are created and deleted are advertised into the group RTNLGRP_NSID. Because callers of rtnl_net_notifyid() already know the id of the peer, there is no need to call __peernet2id() in rtnl_net_fill(). Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-07netns: minor cleanup in rtnl_net_getid()Nicolas Dichtel
No need to initialize err, it will be overridden by the value of nlmsg_parse(). Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/mellanox/mlx4/cmd.c net/core/fib_rules.c net/ipv4/fib_frontend.c The fib_rules.c and fib_frontend.c conflicts were locking adjustments in 'net' overlapping addition and removal of code in 'net-next'. The mlx4 conflict was a bug fix in 'net' happening in the same place a constant was being replaced with a more suitable macro. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03netns: don't allocate an id for dead netnsNicolas Dichtel
First, let's explain the problem. Suppose you have an ipip interface that stands in the netns foo and its link part in the netns bar (so the netns bar has an nsid into the netns foo). Now, you remove the netns bar: - the bar nsid into the netns foo is removed - the netns exit method of ipip is called, thus our ipip iface is removed: => a netlink message is built in the netns foo to advertise this deletion => this netlink message requests an nsid for bar, thus a new nsid is allocated for bar and never removed. This patch adds a check in peernet2id() so that an id cannot be allocated for a netns which is currently destroyed. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03Revert "netns: don't clear nsid too early on removal"Nicolas Dichtel
This reverts commit 4217291e592d ("netns: don't clear nsid too early on removal"). This is not the right fix, it introduces races. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/usb/asix_common.c drivers/net/usb/sr9800.c drivers/net/usb/usbnet.c include/linux/usb/usbnet.h net/ipv4/tcp_ipv4.c net/ipv6/tcp_ipv6.c The TCP conflicts were overlapping changes. In 'net' we added a READ_ONCE() to the socket cached RX route read, whilst in 'net-next' Eric Dumazet touched the surrounding code dealing with how mini sockets are handled. With USB, it's a case of the same bug fix first going into net-next and then I cherry picked it back into net. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-29netns: don't clear nsid too early on removalNicolas Dichtel
With the current code, ids are removed too early. Suppose you have an ipip interface that stands in the netns foo and its link part in the netns bar (so the netns bar has an nsid into the netns foo). Now, you remove the netns bar: - the bar nsid into the netns foo is removed - the netns exit method of ipip is called, thus our ipip iface is removed: => a netlink message is sent in the netns foo to advertise this deletion => this netlink message requests an nsid for bar, thus a new nsid is allocated for bar and never removed. We must remove nsids when we are sure that nobody will refer to netns currently cleaned. Fixes: 0c7aecd4bde4 ("netns: add rtnl cmd to add and get peer netns ids") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-12net: Kill hold_net release_netEric W. Biederman
hold_net and release_net were an idea that turned out to be useless. The code has been disabled since 2008. Kill the code it is long past due. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-04Merge tag 'mac80211-next-for-davem-2015-02-03' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next Last round of updates for net-next: * revert a patch that caused a regression with mesh userspace (Bob) * fix a number of suspend/resume related races (from Emmanuel, Luca and myself - we'll look at backporting later) * add software implementations for new ciphers (Jouni) * add a new ACPI ID for Broadcom's rfkill (Mika) * allow using netns FD for wireless (Vadim) * some other cleanups (various) Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-23vxlan: advertise netns of vxlan dev in fdb msgNicolas Dichtel
Netlink FDB messages are sent in the link netns. The header of these messages contains the ifindex (ndm_ifindex) of the netdevice, but this ifindex is unusable in case of x-netns vxlan. I named the new attribute NDA_NDM_IFINDEX_NETNSID, to avoid confusion with NDA_IFINDEX. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-23nl80211: Allow set network namespace by fdVadim Kochan
Added new NL80211_ATTR_NETNS_FD which allows to set namespace via nl80211 by fd. Signed-off-by: Vadim Kochan <vadim4j@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-01-19netns: add rtnl cmd to add and get peer netns idsNicolas Dichtel
With this patch, a user can define an id for a peer netns by providing a FD or a PID. These ids are local to the netns where it is added (ie valid only into this netns). The main function (ie the one exported to other module), peernet2id(), allows to get the id of a peer netns. If no id has been assigned by the user, this function allocates one. These ids will be used in netlink messages to point to a peer netns, for example in case of a x-netns interface. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-04bury struct proc_ns in fs/procAl Viro
a) make get_proc_ns() return a pointer to struct ns_common b) mirror ns_ops in dentry->d_fsdata of ns dentries, so that is_mnt_ns_file() could get away with fewer dereferences. That way struct proc_ns becomes invisible outside of fs/proc/*.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-04copy address of proc_ns_ops into ns_commonAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-04new helpers: ns_alloc_inum/ns_free_inumAl Viro
take struct ns_common *, for now simply wrappers around proc_{alloc,free}_inum() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-04make proc_ns_operations work with struct ns_common * instead of void *Al Viro
We can do that now. And kill ->inum(), while we are at it - all instances are identical. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-04netns: switch ->get()/->put()/->install()/->inum() to working with &net->nsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-04common object embedded into various struct ....nsAl Viro
for now - just move corresponding ->proc_inum instances over there Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-09-09netns: remove one sparse warningEric Dumazet
net/core/net_namespace.c:227:18: warning: incorrect type in argument 1 (different address spaces) net/core/net_namespace.c:227:18: expected void const *<noident> net/core/net_namespace.c:227:18: got struct net_generic [noderef] <asn:4>*gen We can use rcu_access_pointer() here as read-side access to the pointer was removed at least one grace period ago. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-29namespaces: Use task_lock and not rcu to protect nsproxyEric W. Biederman
The synchronous syncrhonize_rcu in switch_task_namespaces makes setns a sufficiently expensive system call that people have complained. Upon inspect nsproxy no longer needs rcu protection for remote reads. remote reads are rare. So optimize for same process reads and write by switching using rask_lock instead. This yields a simpler to understand lock, and a faster setns system call. In particular this fixes a performance regression observed by Rafael David Tinoco <rafael.tinoco@canonical.com>. This is effectively a revert of Pavel Emelyanov's commit cf7b708c8d1d7a27736771bcf4c457b332b0f818 Make access to task's nsproxy lighter from 2007. The race this originialy fixed no longer exists as do_notify_parent uses task_active_pid_ns(parent) instead of parent->nsproxy. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/bonding/bond_alb.c drivers/net/ethernet/altera/altera_msgdma.c drivers/net/ethernet/altera/altera_sgdma.c net/ipv6/xfrm6_output.c Several cases of overlapping changes. The xfrm6_output.c has a bug fix which overlaps the renaming of skb->local_df to skb->ignore_df. In the Altera TSE driver cases, the register access cleanups in net-next overlapped with bug fixes done in net. Similarly a bug fix to send ALB packets in the bonding driver using the right source address overlaps with cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-15rtnetlink: wait for unregistering devices in rtnl_link_unregister()Cong Wang
From: Cong Wang <cwang@twopensource.com> commit 50624c934db18ab90 (net: Delay default_device_exit_batch until no devices are unregistering) introduced rtnl_lock_unregistering() for default_device_exit_batch(). Same race could happen we when rmmod a driver which calls rtnl_link_unregister() as we call dev->destructor without rtnl lock. For long term, I think we should clean up the mess of netdev_run_todo() and net namespce exit code. Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-26net_namespace: trivial cleanupxiao jin
Do not initialize net_kill_list twice. list_replace_init() already takes care of initializing net_kill_list. We don't need to initialize it with LIST_HEAD() beforehand. Signed-off-by: xiao jin <jin.xiao@intel.com> Reviewed-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-30userns: Kill nsown_capable it makes the wrong thing easyEric W. Biederman
nsown_capable is a special case of ns_capable essentially for just CAP_SETUID and CAP_SETGID. For the existing users it doesn't noticably simplify things and from the suggested patches I have seen it encourages people to do the wrong thing. So remove nsown_capable. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-05-01proc: Split the namespace stuff out into linux/proc_ns.hDavid Howells
Split the proc namespace stuff out into linux/proc_ns.h. Signed-off-by: David Howells <dhowells@redhat.com> cc: netdev@vger.kernel.org cc: Serge E. Hallyn <serge.hallyn@ubuntu.com> cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-14userns: Require CAP_SYS_ADMIN for most uses of setns.Eric W. Biederman
Andy Lutomirski <luto@amacapital.net> found a nasty little bug in the permissions of setns. With unprivileged user namespaces it became possible to create new namespaces without privilege. However the setns calls were relaxed to only require CAP_SYS_ADMIN in the user nameapce of the targed namespace. Which made the following nasty sequence possible. pid = clone(CLONE_NEWUSER | CLONE_NEWNS); if (pid == 0) { /* child */ system("mount --bind /home/me/passwd /etc/passwd"); } else if (pid != 0) { /* parent */ char path[PATH_MAX]; snprintf(path, sizeof(path), "/proc/%u/ns/mnt"); fd = open(path, O_RDONLY); setns(fd, 0); system("su -"); } Prevent this possibility by requiring CAP_SYS_ADMIN in the current user namespace when joing all but the user namespace. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-11-20proc: Usable inode numbers for the namespace file descriptors.Eric W. Biederman
Assign a unique proc inode to each namespace, and use that inode number to ensure we only allocate at most one proc inode for every namespace in proc. A single proc inode per namespace allows userspace to test to see if two processes are in the same namespace. This has been a long requested feature and only blocked because a naive implementation would put the id in a global space and would ultimately require having a namespace for the names of namespaces, making migration and certain virtualization tricks impossible. We still don't have per superblock inode numbers for proc, which appears necessary for application unaware checkpoint/restart and migrations (if the application is using namespace file descriptors) but that is now allowd by the design if it becomes important. I have preallocated the ipc and uts initial proc inode numbers so their structures can be statically initialized. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-11-20userns: Allow unprivileged use of setns.Eric W. Biederman
- Push the permission check from the core setns syscall into the setns install methods where the user namespace of the target namespace can be determined, and used in a ns_capable call. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-11-18userns: make each net (net_ns) belong to a user_nsEric W. Biederman
The user namespace which creates a new network namespace owns that namespace and all resources created in it. This way we can target capability checks for privileged operations against network resources to the user_ns which created the network namespace in which the resource lives. Privilege to the user namespace which owns the network namespace, or any parent user namespace thereof, provides the same privilege to the network resource. This patch is reworked from a version originally by Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-11-18netns: Deduplicate and fix copy_net_ns when !CONFIG_NET_NSEric W. Biederman
The copy of copy_net_ns used when the network stack is not built is broken as it does not return -EINVAL when attempting to create a new network namespace. We don't even have a previous network namespace. Since we need a copy of copy_net_ns in net/net_namespace.h that is available when the networking stack is not built at all move the correct version of copy_net_ns from net_namespace.c into net_namespace.h Leaving us with just 2 versions of copy_net_ns. One version for when we compile in network namespace suport and another stub for all other occasions. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-07-18net: Statically initialize init_net.dev_base_headRustad, Mark D
This change eliminates an initialization-order hazard most recently seen when netprio_cgroup is built into the kernel. With thanks to Eric Dumazet for catching a bug. Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-17net: core: Use pr_<level>Joe Perches
Use the current logging style. This enables use of dynamic debugging as well. Convert printk(KERN_<LEVEL> to pr_<level>. Add pr_fmt. Remove embedded prefixes, use %s, __func__ instead. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>