user/sven/linux.git/net/l2tp, branch v3.4.78

net: rework recvmsg handler msg_name and msg_namelen logic

2013-12-08T15:29:41Z

[ Upstream commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c ] This patch now always passes msg->msg_namelen as 0. recvmsg handlers must set msg_namelen to the proper size <= sizeof(struct sockaddr_storage) to return msg_name to the user. This prevents numerous uninitialized memory leaks we had in the recvmsg handlers and makes it harder for new code to accidentally leak uninitialized memory. Optimize for the case recvfrom is called with NULL as address. We don't need to copy the address at all, so set it to NULL before invoking the recvmsg handler. We can do so, because all the recvmsg handlers must cope with the case a plain read() is called on them. read() also sets msg_name to NULL. Also document these changes in include/linux/net.h as suggested by David Miller. Changes since RFC: Set msg->msg_name = NULL if user specified a NULL in msg_name but had a non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't affect sendto as it would bail out earlier while trying to copy-in the address. It also more naturally reflects the logic by the callers of verify_iovec. With this change in place I could remove " if (!uaddr || msg_sys->msg_namelen == 0) msg->msg_name = NULL ". This change does not alter the user visible error logic as we ignore msg_namelen as long as msg_name is NULL. Also remove two unnecessary curly brackets in ___sys_recvmsg and change comments to netdev style. Cc: David Miller Suggested-by: Eric Dumazet Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

inet: prevent leakage of uninitialized memory to user in recv syscalls

2013-12-08T15:29:41Z

[ Upstream commit bceaa90240b6019ed73b49965eac7d167610be69 ] Only update *addr_len when we actually fill in sockaddr, otherwise we can return uninitialized memory from the stack to the caller in the recvfrom, recvmmsg and recvmsg syscalls. Drop the the (addr_len == NULL) checks because we only get called with a valid addr_len pointer either from sock_common_recvmsg or inet_recvmsg. If a blocking read waits on a socket which is concurrently shut down we now return zero and set msg_msgnamelen to 0. Reported-by: mpb Suggested-by: Eric Dumazet Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: must disable bh before calling l2tp_xmit_skb()

2013-11-04T12:23:41Z

[ Upstream commit 455cc32bf128e114455d11ad919321ab89a2c312 ] François Cachereul made a very nice bug report and suspected the bh_lock_sock() / bh_unlok_sock() pair used in l2tp_xmit_skb() from process context was not good. This problem was added by commit 6af88da14ee284aaad6e4326da09a89191ab6165 ("l2tp: Fix locking in l2tp_core.c"). l2tp_eth_dev_xmit() runs from BH context, so we must disable BH from other l2tp_xmit_skb() users. [ 452.060011] BUG: soft lockup - CPU#1 stuck for 23s! [accel-pppd:6662] [ 452.061757] Modules linked in: l2tp_ppp l2tp_netlink l2tp_core pppoe pppox ppp_generic slhc ipv6 ext3 mbcache jbd virtio_balloon xfs exportfs dm_mod virtio_blk ata_generic virtio_net floppy ata_piix libata virtio_pci virtio_ring virtio [last unloaded: scsi_wait_scan] [ 452.064012] CPU 1 [ 452.080015] BUG: soft lockup - CPU#2 stuck for 23s! [accel-pppd:6643] [ 452.080015] CPU 2 [ 452.080015] [ 452.080015] Pid: 6643, comm: accel-pppd Not tainted 3.2.46.mini #1 Bochs Bochs [ 452.080015] RIP: 0010:[] [] do_raw_spin_lock+0x17/0x1f [ 452.080015] RSP: 0018:ffff88007125fc18 EFLAGS: 00000293 [ 452.080015] RAX: 000000000000aba9 RBX: ffffffff811d0703 RCX: 0000000000000000 [ 452.080015] RDX: 00000000000000ab RSI: ffff8800711f6896 RDI: ffff8800745c8110 [ 452.080015] RBP: ffff88007125fc18 R08: 0000000000000020 R09: 0000000000000000 [ 452.080015] R10: 0000000000000000 R11: 0000000000000280 R12: 0000000000000286 [ 452.080015] R13: 0000000000000020 R14: 0000000000000240 R15: 0000000000000000 [ 452.080015] FS: 00007fdc0cc24700(0000) GS:ffff8800b6f00000(0000) knlGS:0000000000000000 [ 452.080015] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 452.080015] CR2: 00007fdb054899b8 CR3: 0000000074404000 CR4: 00000000000006a0 [ 452.080015] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 452.080015] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 452.080015] Process accel-pppd (pid: 6643, threadinfo ffff88007125e000, task ffff8800b27e6dd0) [ 452.080015] Stack: [ 452.080015] ffff88007125fc28 ffffffff81256559 ffff88007125fc98 ffffffffa01b2bd1 [ 452.080015] ffff88007125fc58 000000000000000c 00000000029490d0 0000009c71dbe25e [ 452.080015] 000000000000005c 000000080000000e 0000000000000000 ffff880071170600 [ 452.080015] Call Trace: [ 452.080015] [] _raw_spin_lock+0xe/0x10 [ 452.080015] [] l2tp_xmit_skb+0x189/0x4ac [l2tp_core] [ 452.080015] [] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.080015] [] __sock_sendmsg_nosec+0x22/0x24 [ 452.080015] [] sock_sendmsg+0xa1/0xb6 [ 452.080015] [] ? __schedule+0x5c1/0x616 [ 452.080015] [] ? __dequeue_signal+0xb7/0x10c [ 452.080015] [] ? fget_light+0x75/0x89 [ 452.080015] [] ? sockfd_lookup_light+0x20/0x56 [ 452.080015] [] sys_sendto+0x10c/0x13b [ 452.080015] [] system_call_fastpath+0x16/0x1b [ 452.080015] Code: 81 48 89 e5 72 0c 31 c0 48 81 ff 45 66 25 81 0f 92 c0 5d c3 55 b8 00 01 00 00 48 89 e5 f0 66 0f c1 07 0f b6 d4 38 d0 74 06 f3 90 <8a> 07 eb f6 5d c3 90 90 55 48 89 e5 9c 58 0f 1f 44 00 00 5d c3 [ 452.080015] Call Trace: [ 452.080015] [] _raw_spin_lock+0xe/0x10 [ 452.080015] [] l2tp_xmit_skb+0x189/0x4ac [l2tp_core] [ 452.080015] [] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.080015] [] __sock_sendmsg_nosec+0x22/0x24 [ 452.080015] [] sock_sendmsg+0xa1/0xb6 [ 452.080015] [] ? __schedule+0x5c1/0x616 [ 452.080015] [] ? __dequeue_signal+0xb7/0x10c [ 452.080015] [] ? fget_light+0x75/0x89 [ 452.080015] [] ? sockfd_lookup_light+0x20/0x56 [ 452.080015] [] sys_sendto+0x10c/0x13b [ 452.080015] [] system_call_fastpath+0x16/0x1b [ 452.064012] [ 452.064012] Pid: 6662, comm: accel-pppd Not tainted 3.2.46.mini #1 Bochs Bochs [ 452.064012] RIP: 0010:[] [] do_raw_spin_lock+0x19/0x1f [ 452.064012] RSP: 0018:ffff8800b6e83ba0 EFLAGS: 00000297 [ 452.064012] RAX: 000000000000aaa9 RBX: ffff8800b6e83b40 RCX: 0000000000000002 [ 452.064012] RDX: 00000000000000aa RSI: 000000000000000a RDI: ffff8800745c8110 [ 452.064012] RBP: ffff8800b6e83ba0 R08: 000000000000c802 R09: 000000000000001c [ 452.064012] R10: ffff880071096c4e R11: 0000000000000006 R12: ffff8800b6e83b18 [ 452.064012] R13: ffffffff8125d51e R14: ffff8800b6e83ba0 R15: ffff880072a589c0 [ 452.064012] FS: 00007fdc0b81e700(0000) GS:ffff8800b6e80000(0000) knlGS:0000000000000000 [ 452.064012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 452.064012] CR2: 0000000000625208 CR3: 0000000074404000 CR4: 00000000000006a0 [ 452.064012] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 452.064012] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 452.064012] Process accel-pppd (pid: 6662, threadinfo ffff88007129a000, task ffff8800744f7410) [ 452.064012] Stack: [ 452.064012] ffff8800b6e83bb0 ffffffff81256559 ffff8800b6e83bc0 ffffffff8121c64a [ 452.064012] ffff8800b6e83bf0 ffffffff8121ec7a ffff880072a589c0 ffff880071096c62 [ 452.064012] 0000000000000011 ffffffff81430024 ffff8800b6e83c80 ffffffff8121f276 [ 452.064012] Call Trace: [ 452.064012] [ 452.064012] [] _raw_spin_lock+0xe/0x10 [ 452.064012] [] spin_lock+0x9/0xb [ 452.064012] [] udp_queue_rcv_skb+0x186/0x269 [ 452.064012] [] __udp4_lib_rcv+0x297/0x4ae [ 452.064012] [] ? raw_rcv+0xe9/0xf0 [ 452.064012] [] udp_rcv+0x1a/0x1c [ 452.064012] [] ip_local_deliver_finish+0x12b/0x1a5 [ 452.064012] [] ip_local_deliver+0x53/0x84 [ 452.064012] [] ip_rcv_finish+0x2bc/0x2f3 [ 452.064012] [] ip_rcv+0x210/0x269 [ 452.064012] [] ? kvm_clock_get_cycles+0x9/0xb [ 452.064012] [] __netif_receive_skb+0x3a5/0x3f7 [ 452.064012] [] netif_receive_skb+0x57/0x5e [ 452.064012] [] ? __netdev_alloc_skb+0x1f/0x3b [ 452.064012] [] virtnet_poll+0x4ba/0x5a4 [virtio_net] [ 452.064012] [] net_rx_action+0x73/0x184 [ 452.064012] [] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [] __do_softirq+0xc3/0x1a8 [ 452.064012] [] ? ack_APIC_irq+0x10/0x12 [ 452.064012] [] ? _raw_spin_lock+0xe/0x10 [ 452.064012] [] call_softirq+0x1c/0x26 [ 452.064012] [] do_softirq+0x45/0x82 [ 452.064012] [] irq_exit+0x42/0x9c [ 452.064012] [] do_IRQ+0x8e/0xa5 [ 452.064012] [] common_interrupt+0x6e/0x6e [ 452.064012] [ 452.064012] [] ? kfree+0x8a/0xa3 [ 452.064012] [] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [] ? l2tp_xmit_skb+0x1dd/0x4ac [l2tp_core] [ 452.064012] [] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.064012] [] __sock_sendmsg_nosec+0x22/0x24 [ 452.064012] [] sock_sendmsg+0xa1/0xb6 [ 452.064012] [] ? __schedule+0x5c1/0x616 [ 452.064012] [] ? __dequeue_signal+0xb7/0x10c [ 452.064012] [] ? fget_light+0x75/0x89 [ 452.064012] [] ? sockfd_lookup_light+0x20/0x56 [ 452.064012] [] sys_sendto+0x10c/0x13b [ 452.064012] [] system_call_fastpath+0x16/0x1b [ 452.064012] Code: 89 e5 72 0c 31 c0 48 81 ff 45 66 25 81 0f 92 c0 5d c3 55 b8 00 01 00 00 48 89 e5 f0 66 0f c1 07 0f b6 d4 38 d0 74 06 f3 90 8a 07 f6 5d c3 90 90 55 48 89 e5 9c 58 0f 1f 44 00 00 5d c3 55 48 [ 452.064012] Call Trace: [ 452.064012] [] _raw_spin_lock+0xe/0x10 [ 452.064012] [] spin_lock+0x9/0xb [ 452.064012] [] udp_queue_rcv_skb+0x186/0x269 [ 452.064012] [] __udp4_lib_rcv+0x297/0x4ae [ 452.064012] [] ? raw_rcv+0xe9/0xf0 [ 452.064012] [] udp_rcv+0x1a/0x1c [ 452.064012] [] ip_local_deliver_finish+0x12b/0x1a5 [ 452.064012] [] ip_local_deliver+0x53/0x84 [ 452.064012] [] ip_rcv_finish+0x2bc/0x2f3 [ 452.064012] [] ip_rcv+0x210/0x269 [ 452.064012] [] ? kvm_clock_get_cycles+0x9/0xb [ 452.064012] [] __netif_receive_skb+0x3a5/0x3f7 [ 452.064012] [] netif_receive_skb+0x57/0x5e [ 452.064012] [] ? __netdev_alloc_skb+0x1f/0x3b [ 452.064012] [] virtnet_poll+0x4ba/0x5a4 [virtio_net] [ 452.064012] [] net_rx_action+0x73/0x184 [ 452.064012] [] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [] __do_softirq+0xc3/0x1a8 [ 452.064012] [] ? ack_APIC_irq+0x10/0x12 [ 452.064012] [] ? _raw_spin_lock+0xe/0x10 [ 452.064012] [] call_softirq+0x1c/0x26 [ 452.064012] [] do_softirq+0x45/0x82 [ 452.064012] [] irq_exit+0x42/0x9c [ 452.064012] [] do_IRQ+0x8e/0xa5 [ 452.064012] [] common_interrupt+0x6e/0x6e [ 452.064012] [] ? kfree+0x8a/0xa3 [ 452.064012] [] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [] ? l2tp_xmit_skb+0x1dd/0x4ac [l2tp_core] [ 452.064012] [] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.064012] [] __sock_sendmsg_nosec+0x22/0x24 [ 452.064012] [] sock_sendmsg+0xa1/0xb6 [ 452.064012] [] ? __schedule+0x5c1/0x616 [ 452.064012] [] ? __dequeue_signal+0xb7/0x10c [ 452.064012] [] ? fget_light+0x75/0x89 [ 452.064012] [] ? sockfd_lookup_light+0x20/0x56 [ 452.064012] [] sys_sendto+0x10c/0x13b [ 452.064012] [] system_call_fastpath+0x16/0x1b Reported-by: François Cachereul Tested-by: François Cachereul Signed-off-by: Eric Dumazet Cc: James Chapman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: add missing .owner to struct pppox_proto

2013-07-28T23:26:02Z

[ Upstream commit e1558a93b61962710733dc8c11a2bc765607f1cd ] Add missing .owner of struct pppox_proto. This prevents the module from being removed from underneath its users. Signed-off-by: Wei Yongjun Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: Fix sendmsg() return value

2013-06-27T18:27:33Z

[ Upstream commit a6f79d0f26704214b5b702bbac525cb72997f984 ] PPPoL2TP sockets should comply with the standard send*() return values (i.e. return number of bytes sent instead of 0 upon success). Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: Fix PPP header erasure and memory leak

2013-06-27T18:27:33Z

[ Upstream commit 55b92b7a11690bc377b5d373872a6b650ae88e64 ] Copy user data after PPP framing header. This prevents erasure of the added PPP header and avoids leaking two bytes of uninitialised memory at the end of skb's data buffer. Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: Restore socket refcount when sendmsg succeeds

2013-03-20T20:05:01Z

[ Upstream commit 8b82547e33e85fc24d4d172a93c796de1fefa81a ] The sendmsg() syscall handler for PPPoL2TP doesn't decrease the socket reference counter after successful transmissions. Any successful sendmsg() call from userspace will then increase the reference counter forever, thus preventing the kernel's session and tunnel data from being freed later on. The problem only happens when writing directly on L2TP sockets. PPP sockets attached to L2TP are unaffected as the PPP subsystem uses pppol2tp_xmit() which symmetrically increase/decrease reference counters. This patch adds the missing call to sock_put() before returning from pppol2tp_sendmsg(). Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: fix oops in l2tp_eth_create() error path

2012-11-17T21:16:18Z

[ Upstream commit 789336360e0a2aeb9750c16ab704a02cbe035e9e ] When creating an L2TPv3 Ethernet session, if register_netdev() should fail for any reason (for example, automatic naming for "l2tpeth%d" interfaces hits the 32k-interface limit), the netdev is freed in the error path. However, the l2tp_eth_sess structure's dev pointer is left uncleared, and this results in l2tp_eth_delete() then attempting to unregister the same netdev later in the session teardown. This results in an oops. To avoid this, clear the session dev pointer in the error path. Signed-off-by: Tom Parkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: fix a typo in l2tp_eth_dev_recv()

2012-10-12T20:38:45Z

[ Upstream commit c0cc88a7627c333de50b07b7c60b1d49d9d2e6cc ] While investigating l2tp bug, I hit a bug in eth_type_trans(), because not enough bytes were pulled in skb head. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: avoid to use synchronize_rcu in tunnel free function

2012-10-02T17:29:42Z

[ Upstream commit 99469c32f79a32d8481f87be0d3c66dad286f4ec ] Avoid to use synchronize_rcu in l2tp_tunnel_free because context may be atomic. Signed-off-by: Dmitry Kozlov Signed-off-by: David S. Miller