kernel.git/net/core/net_namespace.c, branch linux-2.6.27.y

net: net_assign_generic() fix

2009-09-15T17:37:21Z

[ Upstream commit 144586301f6af5ae5943a002f030d8c626fa4fdd ] memcpy() should take into account size of pointers, not only number of pointers to copy. Signed-off-by: Eric Dumazet Acked-by: Pavel Emelyanov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

netns: Don't receive new packets in a dead network namespace.

2008-06-21T05:16:51Z

Alexey Dobriyan writes: > Subject: ICMP sockets destruction vs ICMP packets oops > After icmp_sk_exit() nuked ICMP sockets, we get an interrupt. > icmp_reply() wants ICMP socket. > > Steps to reproduce: > > launch shell in new netns > move real NIC to netns > setup routing > ping -i 0 > exit from shell > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 > IP: [] icmp_sk+0x17/0x30 > PGD 17f3cd067 PUD 17f3ce067 PMD 0 > Oops: 0000 [1] PREEMPT SMP DEBUG_PAGEALLOC > CPU 0 > Modules linked in: usblp usbcore > Pid: 0, comm: swapper Not tainted 2.6.26-rc6-netns-ct #4 > RIP: 0010:[] [] icmp_sk+0x17/0x30 > RSP: 0018:ffffffff8057fc30 EFLAGS: 00010286 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff81017c7db900 > RDX: 0000000000000034 RSI: ffff81017c7db900 RDI: ffff81017dc41800 > RBP: ffffffff8057fc40 R08: 0000000000000001 R09: 000000000000a815 > R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff8057fd28 > R13: ffffffff8057fd00 R14: ffff81017c7db938 R15: ffff81017dc41800 > FS: 0000000000000000(0000) GS:ffffffff80525000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b > CR2: 0000000000000000 CR3: 000000017fcda000 CR4: 00000000000006e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Process swapper (pid: 0, threadinfo ffffffff8053a000, task ffffffff804fa4a0) > Stack: 0000000000000000 ffff81017c7db900 ffffffff8057fcf0 ffffffff803fcfe4 > ffffffff804faa38 0000000000000246 0000000000005a40 0000000000000246 > 000000000001ffff ffff81017dd68dc0 0000000000005a40 0000000055342436 > Call Trace: > [] icmp_reply+0x44/0x1e0 > [] ? ip_route_input+0x23a/0x1360 > [] icmp_echo+0x65/0x70 > [] icmp_rcv+0x180/0x1b0 > [] ip_local_deliver+0xf4/0x1f0 > [] ip_rcv+0x33b/0x650 > [] netif_receive_skb+0x27a/0x340 > [] process_backlog+0x9d/0x100 > [] net_rx_action+0x18d/0x250 > [] __do_softirq+0x75/0x100 > [] call_softirq+0x1c/0x30 > [] do_softirq+0x65/0xa0 > [] irq_exit+0x97/0xa0 > [] do_IRQ+0xa8/0x130 > [] ? mwait_idle+0x0/0x60 > [] ret_from_intr+0x0/0xf > [] ? mwait_idle+0x4c/0x60 > [] ? mwait_idle+0x43/0x60 > [] ? cpu_idle+0x57/0xa0 > [] ? rest_init+0x70/0x80 > Code: 10 5b 41 5c 41 5d 41 5e c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53 > 48 83 ec 08 48 8b 9f 78 01 00 00 e8 2b c7 f1 ff 89 c0 <48> 8b 04 c3 48 83 c4 08 > 5b c9 c3 66 66 66 66 66 2e 0f 1f 84 00 > RIP [] icmp_sk+0x17/0x30 > RSP > CR2: 0000000000000000 > ---[ end trace ea161157b76b33e8 ]--- > Kernel panic - not syncing: Aiee, killing interrupt handler! Receiving packets while we are cleaning up a network namespace is a racy proposition. It is possible when the packet arrives that we have removed some but not all of the state we need to fully process it. We have the choice of either playing wack-a-mole with the cleanup routines or simply dropping packets when we don't have a network namespace to handle them. Since the check looks inexpensive in netif_receive_skb let's just drop the incoming packets. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller

[NETNS]: Make netns refconting debug like a socket one.

2008-04-16T08:58:04Z

Make release_net/hold_net noop for performance-hungry people. This is a debug staff and should be used in the debug mode only. Add check for net != NULL in hold/release calls. This will be required later on. [ Added minor simplifications suggested by Brian Haley. -DaveM ] Signed-off-by: Denis V. Lunev Signed-off-by: David S. Miller

[NETNS]: The generic per-net pointers.

2008-04-15T07:36:08Z

Add the elastic array of void * pointer to the struct net. The access rules are simple: 1. register the ops with register_pernet_gen_device to get the id of your private pointer 2. call net_assign_generic() to put the private data on the struct net (most preferably this should be done in the ->init callback of the ops registered) 3. do not store any private reference on the net_generic array; 4. do not change this pointer while the net is alive; 5. use the net_generic() to get the pointer. When adding a new pointer, I copy the old array, replace it with a new one and schedule the old for kfree after an RCU grace period. Since the net_generic explores the net->gen array inside rcu read section and once set the net->gen->ptr[x] pointer never changes, this grants us a safe access to generic pointers. Quoting Paul: "... RCU is protecting -only- the net_generic structure that net_generic() is traversing, and the [pointer] returned by net_generic() is protected by a reference counter in the upper-level struct net." Signed-off-by: Pavel Emelyanov Acked-by: Paul E. McKenney Signed-off-by: David S. Miller

[NETNS]: The net-subsys IDs generator.

2008-04-15T07:35:23Z

To make some per-net generic pointers, we need some way to address them, i.e. - IDs. This is simple IDA-based IDs generator for pernet subsystems. Addressing questions about potential checkpoint/restart problems: these IDs are "lite-offsets" within the net structure and are by no means supposed to be exported to the userspace. Since it will be used in the nearest future by devices only (tun, vlan, tunnels, bridge, etc), I make it resemble the functionality of register_pernet_device(). The new ids is stored in the *id pointer _before_ calling the init callback to make this id available in this callback. Signed-off-by: Pavel Emelyanov Signed-off-by: David S. Miller

typo fixes in net/core/net_namespace.c

2008-02-03T15:56:48Z

Signed-off-by: Oliver Pinter Signed-off-by: Adrian Bunk

[NET]: Make netns cleanup to run in a separate queue

2008-01-28T22:54:35Z

This patch adds a separate workqueue for cleaning up a network namespace. If we use the keventd workqueue to execute cleanup_net(), there is a problem to unregister devices in IPv6. Indeed the code that cleans up also schedule work in keventd: as long as cleanup_net() hasn't return, dst_gc_task() cannot run and as long as dst_gc_task() has not run, there are still some references pending on the net devices and cleanup_net() can not unregister and exit the keventd workqueue. Signed-off-by: Benjamin Thery Signed-off-by: Daniel Lezcano Acked-by: Denis V. Lunev Acked-By: Kirill Korotaev Signed-off-by: David S. Miller

[NETNS]: Re-export init_net via EXPORT_SYMBOL.

2008-01-23T11:11:42Z

init_net is used added as a parameter to a lot of old API calls, f.e. ip_dev_find. These calls were exported as EXPORT_SYMBOL. So, export init_net as EXPORT_SYMBOL to keep networking API consistent. Signed-off-by: Denis V. Lunev Signed-off-by: David S. Miller

[NET]: Cleanup pernet operation without CONFIG_NET_NS

2007-11-13T11:23:21Z

If CONFIG_NET_NS is not set, the only namespace is possible. This patch removes list of pernet_operations and cleanups code a bit. This list is not needed if there are no namespaces. We should just call ->init method. Additionally, the ->exit will be called on module unloading only. This case is safe - the code is not discarded. For the in/kernel code, ->exit should never be called. Signed-off-by: Denis V. Lunev Signed-off-by: David S. Miller

[NETNS]: Fix compiler error in net_namespace.c

2007-11-07T12:15:02Z

Because net_free is called by copy_net_ns before its declaration, the compiler gives an error. This patch puts net_free before copy_net_ns to fix this. The compiler error: net/core/net_namespace.c: In function 'copy_net_ns': net/core/net_namespace.c:97: error: implicit declaration of function 'net_free' net/core/net_namespace.c: At top level: net/core/net_namespace.c:104: warning: conflicting types for 'net_free' net/core/net_namespace.c:104: error: static declaration of 'net_free' follows non-static declaration net/core/net_namespace.c:97: error: previous implicit declaration of 'net_free' was here The error was introduced by the '[NET]: Hide the dead code in the net_namespace.c' patch (6a1a3b9f686bb04820a232cc1657ef2c45670709). Signed-off-by: Johann Felix Soden Signed-off-by: David S. Miller