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2017-12-12Merge Linaro linux 4.9.62 into linux-4.9Xie Xiaobo
Signed-off-by: Xiaobo Xie <xiaobo.xie@nxp.com>
2017-10-12l2tp: fix race condition in l2tp_tunnel_deleteSabrina Dubroca
[ Upstream commit 62b982eeb4589b2e6d7c01a90590e3a4c2b2ca19 ] If we try to delete the same tunnel twice, the first delete operation does a lookup (l2tp_tunnel_get), finds the tunnel, calls l2tp_tunnel_delete, which queues it for deletion by l2tp_tunnel_del_work. The second delete operation also finds the tunnel and calls l2tp_tunnel_delete. If the workqueue has already fired and started running l2tp_tunnel_del_work, then l2tp_tunnel_delete will queue the same tunnel a second time, and try to free the socket again. Add a dead flag to prevent firing the workqueue twice. Then we can remove the check of queue_work's result that was meant to prevent that race but doesn't. Reproducer: ip l2tp add tunnel tunnel_id 3000 peer_tunnel_id 4000 local 192.168.0.2 remote 192.168.0.1 encap udp udp_sport 5000 udp_dport 6000 ip l2tp add session name l2tp1 tunnel_id 3000 session_id 1000 peer_session_id 2000 ip link set l2tp1 up ip l2tp del tunnel tunnel_id 3000 ip l2tp del tunnel tunnel_id 3000 Fixes: f8ccac0e4493 ("l2tp: put tunnel socket release on a workqueue") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-12l2tp: Avoid schedule while atomic in exit_netRidge Kennedy
[ Upstream commit 12d656af4e3d2781b9b9f52538593e1717e7c979 ] While destroying a network namespace that contains a L2TP tunnel a "BUG: scheduling while atomic" can be observed. Enabling lockdep shows that this is happening because l2tp_exit_net() is calling l2tp_tunnel_closeall() (via l2tp_tunnel_delete()) from within an RCU critical section. l2tp_exit_net() takes rcu_read_lock_bh() << list_for_each_entry_rcu() >> l2tp_tunnel_delete() l2tp_tunnel_closeall() __l2tp_session_unhash() synchronize_rcu() << Illegal inside RCU critical section >> BUG: sleeping function called from invalid context in_atomic(): 1, irqs_disabled(): 0, pid: 86, name: kworker/u16:2 INFO: lockdep is turned off. CPU: 2 PID: 86 Comm: kworker/u16:2 Tainted: G W O 4.4.6-at1 #2 Hardware name: Xen HVM domU, BIOS 4.6.1-xs125300 05/09/2016 Workqueue: netns cleanup_net 0000000000000000 ffff880202417b90 ffffffff812b0013 ffff880202410ac0 ffffffff81870de8 ffff880202417bb8 ffffffff8107aee8 ffffffff81870de8 0000000000000c51 0000000000000000 ffff880202417be0 ffffffff8107b024 Call Trace: [<ffffffff812b0013>] dump_stack+0x85/0xc2 [<ffffffff8107aee8>] ___might_sleep+0x148/0x240 [<ffffffff8107b024>] __might_sleep+0x44/0x80 [<ffffffff810b21bd>] synchronize_sched+0x2d/0xe0 [<ffffffff8109be6d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff8105c7bb>] ? __local_bh_enable_ip+0x6b/0xc0 [<ffffffff816a1b00>] ? _raw_spin_unlock_bh+0x30/0x40 [<ffffffff81667482>] __l2tp_session_unhash+0x172/0x220 [<ffffffff81667397>] ? __l2tp_session_unhash+0x87/0x220 [<ffffffff8166888b>] l2tp_tunnel_closeall+0x9b/0x140 [<ffffffff81668c74>] l2tp_tunnel_delete+0x14/0x60 [<ffffffff81668dd0>] l2tp_exit_net+0x110/0x270 [<ffffffff81668d5c>] ? l2tp_exit_net+0x9c/0x270 [<ffffffff815001c3>] ops_exit_list.isra.6+0x33/0x60 [<ffffffff81501166>] cleanup_net+0x1b6/0x280 ... This bug can easily be reproduced with a few steps: $ sudo unshare -n bash # Create a shell in a new namespace # ip link set lo up # ip addr add 127.0.0.1 dev lo # ip l2tp add tunnel remote 127.0.0.1 local 127.0.0.1 tunnel_id 1 \ peer_tunnel_id 1 udp_sport 50000 udp_dport 50000 # ip l2tp add session name foo tunnel_id 1 session_id 1 \ peer_session_id 1 # ip link set foo up # exit # Exit the shell, in turn exiting the namespace $ dmesg ... [942121.089216] BUG: scheduling while atomic: kworker/u16:3/13872/0x00000200 ... To fix this, move the call to l2tp_tunnel_closeall() out of the RCU critical section, and instead call it from l2tp_tunnel_del_work(), which is running from the l2tp_wq workqueue. Fixes: 2b551c6e7d5b ("l2tp: close sessions before initiating tunnel delete") Signed-off-by: Ridge Kennedy <ridge.kennedy@alliedtelesis.co.nz> Acked-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-07l2tp: consider '::' as wildcard address in l2tp_ip6 socket lookupGuillaume Nault
[ Upstream commit 97b84fd6d91766ea57dcc350d78f42639e011c30 ] An L2TP socket bound to the unspecified address should match with any address. If not, it can't receive any packet and __l2tp_ip6_bind_lookup() can't prevent another socket from binding on the same device/tunnel ID. While there, rename the 'addr' variable to 'sk_laddr' (local addr), to make following patch clearer. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-14net: make ndo_get_stats64 a void functionstephen hemminger
The network device operation for reading statistics is only called in one place, and it ignores the return value. Having a structure return value is potentially confusing because some future driver could incorrectly assume that the return value was used. Fix all drivers with ndo_get_stats64 to have a void function. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-05l2tp: take a reference on sessions used in genetlink handlersGuillaume Nault
commit 2777e2ab5a9cf2b4524486c6db1517a6ded25261 upstream. Callers of l2tp_nl_session_find() need to hold a reference on the returned session since there's no guarantee that it isn't going to disappear from under them. Relying on the fact that no l2tp netlink message may be processed concurrently isn't enough: sessions can be deleted by other means (e.g. by closing the PPPOL2TP socket of a ppp pseudowire). l2tp_nl_cmd_session_delete() is a bit special: it runs a callback function that may require a previous call to session->ref(). In particular, for ppp pseudowires, the callback is l2tp_session_delete(), which then calls pppol2tp_session_close() and dereferences the PPPOL2TP socket. The socket might already be gone at the moment l2tp_session_delete() calls session->ref(), so we need to take a reference during the session lookup. So we need to pass the do_ref variable down to l2tp_session_get() and l2tp_session_get_by_ifname(). Since all callers have to be updated, l2tp_session_find_by_ifname() and l2tp_nl_session_find() are renamed to reflect their new behaviour. Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05l2tp: hold session while sending creation notificationsGuillaume Nault
commit 5e6a9e5a3554a5b3db09cdc22253af1849c65dff upstream. l2tp_session_find() doesn't take any reference on the returned session. Therefore, the session may disappear while sending the notification. Use l2tp_session_get() instead and decrement session's refcount once the notification is sent. Fixes: 33f72e6f0c67 ("l2tp : multicast notification to the registered listeners") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05l2tp: fix duplicate session creationGuillaume Nault
commit dbdbc73b44782e22b3b4b6e8b51e7a3d245f3086 upstream. l2tp_session_create() relies on its caller for checking for duplicate sessions. This is racy since a session can be concurrently inserted after the caller's verification. Fix this by letting l2tp_session_create() verify sessions uniqueness upon insertion. Callers need to be adapted to check for l2tp_session_create()'s return code instead of calling l2tp_session_find(). pppol2tp_connect() is a bit special because it has to work on existing sessions (if they're not connected) or to create a new session if none is found. When acting on a preexisting session, a reference must be held or it could go away on us. So we have to use l2tp_session_get() instead of l2tp_session_find() and drop the reference before exiting. Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support") Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05l2tp: ensure session can't get removed during pppol2tp_session_ioctl()Guillaume Nault
commit 57377d63547861919ee634b845c7caa38de4a452 upstream. Holding a reference on session is required before calling pppol2tp_session_ioctl(). The session could get freed while processing the ioctl otherwise. Since pppol2tp_session_ioctl() uses the session's socket, we also need to take a reference on it in l2tp_session_get(). Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05l2tp: fix race in l2tp_recv_common()Guillaume Nault
commit 61b9a047729bb230978178bca6729689d0c50ca2 upstream. Taking a reference on sessions in l2tp_recv_common() is racy; this has to be done by the callers. To this end, a new function is required (l2tp_session_get()) to atomically lookup a session and take a reference on it. Callers then have to manually drop this reference. Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03l2tp: fix PPP pseudo-wire auto-loadingGuillaume Nault
[ Upstream commit 249ee819e24c180909f43c1173c8ef6724d21faf ] PPP pseudo-wire type is 7 (11 is L2TP_PWTYPE_IP). Fixes: f1f39f911027 ("l2tp: auto load type modules") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03l2tp: take reference on sessions being dumpedGuillaume Nault
[ Upstream commit e08293a4ccbcc993ded0fdc46f1e57926b833d63 ] Take a reference on the sessions returned by l2tp_session_find_nth() (and rename it l2tp_session_get_nth() to reflect this change), so that caller is assured that the session isn't going to disappear while processing it. For procfs and debugfs handlers, the session is held in the .start() callback and dropped in .show(). Given that pppol2tp_seq_session_show() dereferences the associated PPPoL2TP socket and that l2tp_dfs_seq_session_show() might call pppol2tp_show(), we also need to call the session's .ref() callback to prevent the socket from going away from under us. Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Fixes: 0ad6614048cf ("l2tp: Add debugfs files for dumping l2tp debug info") Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03l2tp: purge socket queues in the .destruct() callbackGuillaume Nault
[ Upstream commit e91793bb615cf6cdd59c0b6749fe173687bb0947 ] The Rx path may grab the socket right before pppol2tp_release(), but nothing guarantees that it will enqueue packets before skb_queue_purge(). Therefore, the socket can be destroyed without its queues fully purged. Fix this by purging queues in pppol2tp_session_destruct() where we're guaranteed nothing is still referencing the socket. Fixes: 9e9cb6221aa7 ("l2tp: fix userspace reception on plain L2TP sockets") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03l2tp: hold tunnel socket when handling control frames in l2tp_ip and l2tp_ip6Guillaume Nault
[ Upstream commit 94d7ee0baa8b764cf64ad91ed69464c1a6a0066b ] The code following l2tp_tunnel_find() expects that a new reference is held on sk. Either sk_receive_skb() or the discard_put error path will drop a reference from the tunnel's socket. This issue exists in both l2tp_ip and l2tp_ip6. Fixes: a3c18422a4b4 ("l2tp: hold socket before dropping lock in l2tp_ip{, 6}_recv()") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-22l2tp: avoid use-after-free caused by l2tp_ip_backlog_recvPaul Hüber
[ Upstream commit 51fb60eb162ab84c5edf2ae9c63cf0b878e5547e ] l2tp_ip_backlog_recv may not return -1 if the packet gets dropped. The return value is passed up to ip_local_deliver_finish, which treats negative values as an IP protocol number for resubmission. Signed-off-by: Paul Hüber <phueber@kernsp.in> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18l2tp: do not use udp_ioctl()Eric Dumazet
[ Upstream commit 72fb96e7bdbbdd4421b0726992496531060f3636 ] udp_ioctl(), as its name suggests, is used by UDP protocols, but is also used by L2TP :( L2TP should use its own handler, because it really does not look the same. SIOCINQ for instance should not assume UDP checksum or headers. Thanks to Andrey and syzkaller team for providing the report and a nice reproducer. While crashes only happen on recent kernels (after commit 7c13f97ffde6 ("udp: do fwd memory scheduling on dequeue")), this probably needs to be backported to older kernels. Fixes: 7c13f97ffde6 ("udp: do fwd memory scheduling on dequeue") Fixes: 85584672012e ("udp: Fix udp_poll() and ioctl()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-30l2tp: fix address test in __l2tp_ip6_bind_lookup()Guillaume Nault
The '!(addr && ipv6_addr_equal(addr, laddr))' part of the conditional matches if addr is NULL or if addr != laddr. But the intend of __l2tp_ip6_bind_lookup() is to find a sockets with the same address, so the ipv6_addr_equal() condition needs to be inverted. For better clarity and consistency with the rest of the expression, the (!X || X == Y) notation is used instead of !(X && X != Y). Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30l2tp: fix lookup for sockets not bound to a device in l2tp_ipGuillaume Nault
When looking up an l2tp socket, we must consider a null netdevice id as wild card. There are currently two problems caused by __l2tp_ip_bind_lookup() not considering 'dif' as wild card when set to 0: * A socket bound to a device (i.e. with sk->sk_bound_dev_if != 0) never receives any packet. Since __l2tp_ip_bind_lookup() is called with dif == 0 in l2tp_ip_recv(), sk->sk_bound_dev_if is always different from 'dif' so the socket doesn't match. * Two sockets, one bound to a device but not the other, can be bound to the same address. If the first socket binding to the address is the one that is also bound to a device, the second socket can bind to the same address without __l2tp_ip_bind_lookup() noticing the overlap. To fix this issue, we need to consider that any null device index, be it 'sk->sk_bound_dev_if' or 'dif', matches with any other value. We also need to pass the input device index to __l2tp_ip_bind_lookup() on reception so that sockets bound to a device never receive packets from other devices. This patch fixes l2tp_ip6 in the same way. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30l2tp: fix racy socket lookup in l2tp_ip and l2tp_ip6 bind()Guillaume Nault
It's not enough to check for sockets bound to same address at the beginning of l2tp_ip{,6}_bind(): even if no socket is found at that time, a socket with the same address could be bound before we take the l2tp lock again. This patch moves the lookup right before inserting the new socket, so that no change can ever happen to the list between address lookup and socket insertion. Care is taken to avoid side effects on the socket in case of failure. That is, modifications of the socket are done after the lookup, when binding is guaranteed to succeed, and before releasing the l2tp lock, so that concurrent lookups will always see fully initialised sockets. For l2tp_ip, 'ret' is set to -EINVAL before checking the SOCK_ZAPPED bit. Error code was mistakenly set to -EADDRINUSE on error by commit 32c231164b76 ("l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()"). Using -EINVAL restores original behaviour. For l2tp_ip6, the lookup is now always done with the correct bound device. Before this patch, when binding to a link-local address, the lookup was done with the original sk->sk_bound_dev_if, which was later overwritten with addr->l2tp_scope_id. Lookup is now performed with the final sk->sk_bound_dev_if value. Finally, the (addr_len >= sizeof(struct sockaddr_in6)) check has been dropped: addr is a sockaddr_l2tpip6 not sockaddr_in6 and addr_len has already been checked at this point (this part of the code seems to have been copy-pasted from net/ipv6/raw.c). Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30l2tp: hold socket before dropping lock in l2tp_ip{, 6}_recv()Guillaume Nault
Socket must be held while under the protection of the l2tp lock; there is no guarantee that sk remains valid after the read_unlock_bh() call. Same issue for l2tp_ip and l2tp_ip6. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30l2tp: lock socket before checking flags in connect()Guillaume Nault
Socket flags aren't updated atomically, so the socket must be locked while reading the SOCK_ZAPPED flag. This issue exists for both l2tp_ip and l2tp_ip6. For IPv6, this patch also brings error handling for __ip6_datagram_connect() failures. Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-24net: revert "net: l2tp: Treat NET_XMIT_CN as success in l2tp_eth_dev_xmit"WANG Cong
This reverts commit 7c6ae610a1f0, because l2tp_xmit_skb() never returns NET_XMIT_CN, it ignores the return value of l2tp_xmit_core(). Cc: Gao Feng <gfree.wind@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-21net: l2tp: Treat NET_XMIT_CN as success in l2tp_eth_dev_xmitGao Feng
The tc could return NET_XMIT_CN as one congestion notification, but it does not mean the packe is lost. Other modules like ipvlan, macvlan, and others treat NET_XMIT_CN as success too. So l2tp_eth_dev_xmit should add the NET_XMIT_CN check. Signed-off-by: Gao Feng <gfree.wind@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-20l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()Guillaume Nault
Lock socket before checking the SOCK_ZAPPED flag in l2tp_ip6_bind(). Without lock, a concurrent call could modify the socket flags between the sock_flag(sk, SOCK_ZAPPED) test and the lock_sock() call. This way, a socket could be inserted twice in l2tp_ip6_bind_table. Releasing it would then leave a stale pointer there, generating use-after-free errors when walking through the list or modifying adjacent entries. BUG: KASAN: use-after-free in l2tp_ip6_close+0x22e/0x290 at addr ffff8800081b0ed8 Write of size 8 by task syz-executor/10987 CPU: 0 PID: 10987 Comm: syz-executor Not tainted 4.8.0+ #39 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 ffff880031d97838 ffffffff829f835b ffff88001b5a1640 ffff8800081b0ec0 ffff8800081b15a0 ffff8800081b6d20 ffff880031d97860 ffffffff8174d3cc ffff880031d978f0 ffff8800081b0e80 ffff88001b5a1640 ffff880031d978e0 Call Trace: [<ffffffff829f835b>] dump_stack+0xb3/0x118 lib/dump_stack.c:15 [<ffffffff8174d3cc>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:156 [< inline >] print_address_description mm/kasan/report.c:194 [<ffffffff8174d666>] kasan_report_error+0x1f6/0x4d0 mm/kasan/report.c:283 [< inline >] kasan_report mm/kasan/report.c:303 [<ffffffff8174db7e>] __asan_report_store8_noabort+0x3e/0x40 mm/kasan/report.c:329 [< inline >] __write_once_size ./include/linux/compiler.h:249 [< inline >] __hlist_del ./include/linux/list.h:622 [< inline >] hlist_del_init ./include/linux/list.h:637 [<ffffffff8579047e>] l2tp_ip6_close+0x22e/0x290 net/l2tp/l2tp_ip6.c:239 [<ffffffff850b2dfd>] inet_release+0xed/0x1c0 net/ipv4/af_inet.c:415 [<ffffffff851dc5a0>] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:422 [<ffffffff84c4581d>] sock_release+0x8d/0x1d0 net/socket.c:570 [<ffffffff84c45976>] sock_close+0x16/0x20 net/socket.c:1017 [<ffffffff817a108c>] __fput+0x28c/0x780 fs/file_table.c:208 [<ffffffff817a1605>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff813774f9>] task_work_run+0xf9/0x170 [<ffffffff81324aae>] do_exit+0x85e/0x2a00 [<ffffffff81326dc8>] do_group_exit+0x108/0x330 [<ffffffff81348cf7>] get_signal+0x617/0x17a0 kernel/signal.c:2307 [<ffffffff811b49af>] do_signal+0x7f/0x18f0 [<ffffffff810039bf>] exit_to_usermode_loop+0xbf/0x150 arch/x86/entry/common.c:156 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:190 [<ffffffff81006060>] syscall_return_slowpath+0x1a0/0x1e0 arch/x86/entry/common.c:259 [<ffffffff85e4d726>] entry_SYSCALL_64_fastpath+0xc4/0xc6 Object at ffff8800081b0ec0, in cache L2TP/IPv6 size: 1448 Allocated: PID = 10987 [ 1116.897025] [<ffffffff811ddcb6>] save_stack_trace+0x16/0x20 [ 1116.897025] [<ffffffff8174c736>] save_stack+0x46/0xd0 [ 1116.897025] [<ffffffff8174c9ad>] kasan_kmalloc+0xad/0xe0 [ 1116.897025] [<ffffffff8174cee2>] kasan_slab_alloc+0x12/0x20 [ 1116.897025] [< inline >] slab_post_alloc_hook mm/slab.h:417 [ 1116.897025] [< inline >] slab_alloc_node mm/slub.c:2708 [ 1116.897025] [< inline >] slab_alloc mm/slub.c:2716 [ 1116.897025] [<ffffffff817476a8>] kmem_cache_alloc+0xc8/0x2b0 mm/slub.c:2721 [ 1116.897025] [<ffffffff84c4f6a9>] sk_prot_alloc+0x69/0x2b0 net/core/sock.c:1326 [ 1116.897025] [<ffffffff84c58ac8>] sk_alloc+0x38/0xae0 net/core/sock.c:1388 [ 1116.897025] [<ffffffff851ddf67>] inet6_create+0x2d7/0x1000 net/ipv6/af_inet6.c:182 [ 1116.897025] [<ffffffff84c4af7b>] __sock_create+0x37b/0x640 net/socket.c:1153 [ 1116.897025] [< inline >] sock_create net/socket.c:1193 [ 1116.897025] [< inline >] SYSC_socket net/socket.c:1223 [ 1116.897025] [<ffffffff84c4b46f>] SyS_socket+0xef/0x1b0 net/socket.c:1203 [ 1116.897025] [<ffffffff85e4d685>] entry_SYSCALL_64_fastpath+0x23/0xc6 Freed: PID = 10987 [ 1116.897025] [<ffffffff811ddcb6>] save_stack_trace+0x16/0x20 [ 1116.897025] [<ffffffff8174c736>] save_stack+0x46/0xd0 [ 1116.897025] [<ffffffff8174cf61>] kasan_slab_free+0x71/0xb0 [ 1116.897025] [< inline >] slab_free_hook mm/slub.c:1352 [ 1116.897025] [< inline >] slab_free_freelist_hook mm/slub.c:1374 [ 1116.897025] [< inline >] slab_free mm/slub.c:2951 [ 1116.897025] [<ffffffff81748b28>] kmem_cache_free+0xc8/0x330 mm/slub.c:2973 [ 1116.897025] [< inline >] sk_prot_free net/core/sock.c:1369 [ 1116.897025] [<ffffffff84c541eb>] __sk_destruct+0x32b/0x4f0 net/core/sock.c:1444 [ 1116.897025] [<ffffffff84c5aca4>] sk_destruct+0x44/0x80 net/core/sock.c:1452 [ 1116.897025] [<ffffffff84c5ad33>] __sk_free+0x53/0x220 net/core/sock.c:1460 [ 1116.897025] [<ffffffff84c5af23>] sk_free+0x23/0x30 net/core/sock.c:1471 [ 1116.897025] [<ffffffff84c5cb6c>] sk_common_release+0x28c/0x3e0 ./include/net/sock.h:1589 [ 1116.897025] [<ffffffff8579044e>] l2tp_ip6_close+0x1fe/0x290 net/l2tp/l2tp_ip6.c:243 [ 1116.897025] [<ffffffff850b2dfd>] inet_release+0xed/0x1c0 net/ipv4/af_inet.c:415 [ 1116.897025] [<ffffffff851dc5a0>] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:422 [ 1116.897025] [<ffffffff84c4581d>] sock_release+0x8d/0x1d0 net/socket.c:570 [ 1116.897025] [<ffffffff84c45976>] sock_close+0x16/0x20 net/socket.c:1017 [ 1116.897025] [<ffffffff817a108c>] __fput+0x28c/0x780 fs/file_table.c:208 [ 1116.897025] [<ffffffff817a1605>] ____fput+0x15/0x20 fs/file_table.c:244 [ 1116.897025] [<ffffffff813774f9>] task_work_run+0xf9/0x170 [ 1116.897025] [<ffffffff81324aae>] do_exit+0x85e/0x2a00 [ 1116.897025] [<ffffffff81326dc8>] do_group_exit+0x108/0x330 [ 1116.897025] [<ffffffff81348cf7>] get_signal+0x617/0x17a0 kernel/signal.c:2307 [ 1116.897025] [<ffffffff811b49af>] do_signal+0x7f/0x18f0 [ 1116.897025] [<ffffffff810039bf>] exit_to_usermode_loop+0xbf/0x150 arch/x86/entry/common.c:156 [ 1116.897025] [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:190 [ 1116.897025] [<ffffffff81006060>] syscall_return_slowpath+0x1a0/0x1e0 arch/x86/entry/common.c:259 [ 1116.897025] [<ffffffff85e4d726>] entry_SYSCALL_64_fastpath+0xc4/0xc6 Memory state around the buggy address: ffff8800081b0d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8800081b0e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8800081b0e80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8800081b0f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8800081b0f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== The same issue exists with l2tp_ip_bind() and l2tp_ip_bind_table. Fixes: c51ce49735c1 ("l2tp: fix oops in L2TP IP sockets for connect() AF_UNSPEC case") Reported-by: Baozeng Ding <sploving1@gmail.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Baozeng Ding <sploving1@gmail.com> Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20udp: must lock the socket in udp_disconnect()Eric Dumazet
Baozeng Ding reported KASAN traces showing uses after free in udp_lib_get_port() and other related UDP functions. A CONFIG_DEBUG_PAGEALLOC=y kernel would eventually crash. I could write a reproducer with two threads doing : static int sock_fd; static void *thr1(void *arg) { for (;;) { connect(sock_fd, (const struct sockaddr *)arg, sizeof(struct sockaddr_in)); } } static void *thr2(void *arg) { struct sockaddr_in unspec; for (;;) { memset(&unspec, 0, sizeof(unspec)); connect(sock_fd, (const struct sockaddr *)&unspec, sizeof(unspec)); } } Problem is that udp_disconnect() could run without holding socket lock, and this was causing list corruptions. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Baozeng Ding <sploving1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-17l2tp: constify net_device_ops structuresJulia Lawall
Check for net_device_ops structures that are only stored in the netdev_ops field of a net_device structure. This field is declared const, so net_device_ops structures that have this property can be declared as const also. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r disable optional_qualifier@ identifier i; position p; @@ static struct net_device_ops i@p = { ... }; @ok@ identifier r.i; struct net_device e; position p; @@ e.netdev_ops = &i@p; @bad@ position p != {r.p,ok.p}; identifier r.i; struct net_device_ops e; @@ e@i@p @depends on !bad disable optional_qualifier@ identifier r.i; @@ static +const struct net_device_ops i = { ... }; // </smpl> The result of size on this file before the change is: text data bss dec hex filename 3401 931 44 4376 1118 net/l2tp/l2tp_eth.o and after the change it is: text data bss dec hex filename 3993 347 44 4384 1120 net/l2tp/l2tp_eth.o Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/mediatek/mtk_eth_soc.c drivers/net/ethernet/qlogic/qed/qed_dcbx.c drivers/net/phy/Kconfig All conflicts were cases of overlapping commits. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-11l2tp: use IS_ENABLED() instead of checking for built-in or moduleJavier Martinez Canillas
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either built-in or as a module, use that macro instead of open coding the same. Using the macro makes the code more readable by helping abstract away some of the Kconfig built-in and module enable details. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02l2tp: fix use-after-free during module unloadSabrina Dubroca
Tunnel deletion is delayed by both a workqueue (l2tp_tunnel_delete -> wq -> l2tp_tunnel_del_work) and RCU (sk_destruct -> RCU -> l2tp_tunnel_destruct). By the time l2tp_tunnel_destruct() runs to destroy the tunnel and finish destroying the socket, the private data reserved via the net_generic mechanism has already been freed, but l2tp_tunnel_destruct() actually uses this data. Make sure tunnel deletion for the netns has completed before returning from l2tp_exit_net() by first flushing the tunnel removal workqueue, and then waiting for RCU callbacks to complete. Fixes: 167eb17e0b17 ("l2tp: create tunnel sockets in the right namespace") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01l2tp: make nla_policy conststephen hemminger
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
All three conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23l2tp: Refactor the codes with existing macros instead of literal numberGao Feng
Use PPP_ALLSTATIONS, PPP_UI, and SEND_SHUTDOWN instead of 0xff, 0x03, and 2 separately. Signed-off-by: Gao Feng <fgao@ikuai8.com> Acked-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-21Revert "l2tp: Refactor the codes with existing macros instead of literal number"David S. Miller
This reverts commit 5ab1fe72d5490978104fc493615ea29dd7238766. This change still has problems. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-21l2tp: Refactor the codes with existing macros instead of literal numberGao Feng
Use PPP_ALLSTATIONS, PPP_UI, and SEND_SHUTDOWN instead of 0xff, 0x03, and 2 separately. Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-20l2tp: Fix the connect status check in pppol2tp_getnameGao Feng
The sk->sk_state is bits flag, so need use bit operation check instead of value check. Signed-off-by: Gao Feng <fgao@ikuai8.com> Tested-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-26l2tp: Correctly return -EBADF from pppol2tp_getname.phil.turnbull@oracle.com
If 'tunnel' is NULL we should return -EBADF but the 'end_put_sess' path unconditionally sets 'error' back to zero. Rework the error path so it more closely matches pppol2tp_sendmsg. Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-11ipv6: use TOS marks from sockets for routing decisionHannes Frederic Sowa
In IPv6 the ToS values are part of the flowlabel in flowi6 and get extracted during fib rule lookup, but we forgot to correctly initialize the flowlabel before the routing lookup. Reported-by: <liam.mcbirnie@boeing.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/sched/act_police.c net/sched/sch_drr.c net/sched/sch_hfsc.c net/sched/sch_prio.c net/sched/sch_red.c net/sched/sch_tbf.c In net-next the drop methods of the packet schedulers got removed, so the bug fixes to them in 'net' are irrelevant. A packet action unload crash fix conflicts with the addition of the new firstuse timestamp. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-09net: add netdev_lockdep_set_classes() helperEric Dumazet
It is time to add netdev_lockdep_set_classes() helper so that lockdep annotations per device type are easier to manage. This removes a lot of copies and missing annotations. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08l2tp: fix configuration passed to setup_udp_tunnel_sock()Guillaume Nault
Unused fields of udp_cfg must be all zeros. Otherwise setup_udp_tunnel_sock() fills ->gro_receive and ->gro_complete callbacks with garbage, eventually resulting in panic when used by udp_gro_receive(). [ 72.694123] BUG: unable to handle kernel paging request at ffff880033f87d78 [ 72.695518] IP: [<ffff880033f87d78>] 0xffff880033f87d78 [ 72.696530] PGD 26e2067 PUD 26e3067 PMD 342ed063 PTE 8000000033f87163 [ 72.696530] Oops: 0011 [#1] SMP KASAN [ 72.696530] Modules linked in: l2tp_ppp l2tp_netlink l2tp_core ip6_udp_tunnel udp_tunnel pptp gre pppox ppp_generic slhc crc32c_intel ghash_clmulni_intel jitterentropy_rng sha256_generic hmac drbg ansi_cprng aesni_intel evdev aes_x86_64 ablk_helper cryptd lrw gf128mul glue_helper serio_raw acpi_cpufreq button proc\ essor ext4 crc16 jbd2 mbcache virtio_blk virtio_net virtio_pci virtio_ring virtio [ 72.696530] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.7.0-rc1 #1 [ 72.696530] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 72.696530] task: ffff880035b59700 ti: ffff880035b70000 task.ti: ffff880035b70000 [ 72.696530] RIP: 0010:[<ffff880033f87d78>] [<ffff880033f87d78>] 0xffff880033f87d78 [ 72.696530] RSP: 0018:ffff880035f87bc0 EFLAGS: 00010246 [ 72.696530] RAX: ffffed000698f996 RBX: ffff88003326b840 RCX: ffffffff814cc823 [ 72.696530] RDX: ffff88003326b840 RSI: ffff880033e48038 RDI: ffff880034c7c780 [ 72.696530] RBP: ffff880035f87c18 R08: 000000000000a506 R09: 0000000000000000 [ 72.696530] R10: ffff880035f87b38 R11: ffff880034b9344d R12: 00000000ebfea715 [ 72.696530] R13: 0000000000000000 R14: ffff880034c7c780 R15: 0000000000000000 [ 72.696530] FS: 0000000000000000(0000) GS:ffff880035f80000(0000) knlGS:0000000000000000 [ 72.696530] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 72.696530] CR2: ffff880033f87d78 CR3: 0000000033c98000 CR4: 00000000000406a0 [ 72.696530] Stack: [ 72.696530] ffffffff814cc834 ffff880034b93468 0000001481416818 ffff88003326b874 [ 72.696530] ffff880034c7ccb0 ffff880033e48038 ffff88003326b840 ffff880034b93462 [ 72.696530] ffff88003326b88a ffff88003326b88c ffff880034b93468 ffff880035f87c70 [ 72.696530] Call Trace: [ 72.696530] <IRQ> [ 72.696530] [<ffffffff814cc834>] ? udp_gro_receive+0x1c6/0x1f9 [ 72.696530] [<ffffffff814ccb1c>] udp4_gro_receive+0x2b5/0x310 [ 72.696530] [<ffffffff814d989b>] inet_gro_receive+0x4a3/0x4cd [ 72.696530] [<ffffffff81431b32>] dev_gro_receive+0x584/0x7a3 [ 72.696530] [<ffffffff810adf7a>] ? __lock_is_held+0x29/0x64 [ 72.696530] [<ffffffff814321f7>] napi_gro_receive+0x124/0x21d [ 72.696530] [<ffffffffa000b145>] virtnet_receive+0x8df/0x8f6 [virtio_net] [ 72.696530] [<ffffffffa000b27e>] virtnet_poll+0x1d/0x8d [virtio_net] [ 72.696530] [<ffffffff81431350>] net_rx_action+0x15b/0x3b9 [ 72.696530] [<ffffffff815893d6>] __do_softirq+0x216/0x546 [ 72.696530] [<ffffffff81062392>] irq_exit+0x49/0xb6 [ 72.696530] [<ffffffff81588e9a>] do_IRQ+0xe2/0xfa [ 72.696530] [<ffffffff81587a49>] common_interrupt+0x89/0x89 [ 72.696530] <EOI> [ 72.696530] [<ffffffff810b05df>] ? trace_hardirqs_on_caller+0x229/0x270 [ 72.696530] [<ffffffff8102b3c7>] ? default_idle+0x1c/0x2d [ 72.696530] [<ffffffff8102b3c5>] ? default_idle+0x1a/0x2d [ 72.696530] [<ffffffff8102bb8c>] arch_cpu_idle+0xa/0xc [ 72.696530] [<ffffffff810a6c39>] default_idle_call+0x1a/0x1c [ 72.696530] [<ffffffff810a6d96>] cpu_startup_entry+0x15b/0x20f [ 72.696530] [<ffffffff81039a81>] start_secondary+0x12c/0x133 [ 72.696530] Code: ff ff ff ff ff ff ff ff ff ff 7f ff ff ff ff ff ff ff 7f 00 7e f8 33 00 88 ff ff 6d 61 58 81 ff ff ff ff 5e de 0a 81 ff ff ff ff <00> 5c e2 34 00 88 ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 72.696530] RIP [<ffff880033f87d78>] 0xffff880033f87d78 [ 72.696530] RSP <ffff880035f87bc0> [ 72.696530] CR2: ffff880033f87d78 [ 72.696530] ---[ end trace ad7758b9a1dccf99 ]--- [ 72.696530] Kernel panic - not syncing: Fatal exception in interrupt [ 72.696530] Kernel Offset: disabled [ 72.696530] ---[ end Kernel panic - not syncing: Fatal exception in interrupt v2: use empty initialiser instead of "{ NULL }" to avoid relying on first field's type. Fixes: 38fd2af24fcf ("udp: Add socket based GRO and config") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07net_sched: transform qdisc running bit into a seqcountEric Dumazet
Instead of using a single bit (__QDISC___STATE_RUNNING) in sch->__state, use a seqcount. This adds lockdep support, but more importantly it will allow us to sample qdisc/class statistics without having to grab qdisc root lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-30net: l2tp: Make l2tp_ip6 namespace awareShmulik Ladkani
l2tp_ip6 tunnel and session lookups were still using init_net, although the l2tp core infrastructure already supports lookups keyed by 'net'. As a result, l2tp_ip6_recv discarded packets for tunnels/sessions created in namespaces other than the init_net. Fix, by using dev_net(skb->dev) or sock_net(sk) where appropriate. Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/ipv4/ip_gre.c Minor conflicts between tunnel bug fixes in net and ipv6 tunnel cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-03ipv6: add new struct ipcm6_cookieWei Wang
In the sendmsg function of UDP, raw, ICMP and l2tp sockets, we use local variables like hlimits, tclass, opt and dontfrag and pass them to corresponding functions like ip6_make_skb, ip6_append_data and xxx_push_pending_frames. This is not a good practice and makes it hard to add new parameters. This fix introduces a new struct ipcm6_cookie similar to ipcm_cookie in ipv4 and include the above mentioned variables. And we only pass the pointer to this structure to corresponding functions. This makes it easier to add new parameters in the future and makes the function cleaner. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-01net: l2tp: fix reversed udp6 checksum flagsWang Shanker
This patch fixes a bug which causes the behavior of whether to ignore udp6 checksum of udp6 encapsulated l2tp tunnel contrary to what userspace program requests. When the flag `L2TP_ATTR_UDP_ZERO_CSUM6_RX` is set by userspace, it is expected that udp6 checksums of received packets of the l2tp tunnel to create should be ignored. In `l2tp_netlink.c`: `l2tp_nl_cmd_tunnel_create()`, `cfg.udp6_zero_rx_checksums` is set according to the flag, and then passed to `l2tp_core.c`: `l2tp_tunnel_create()` and then `l2tp_tunnel_sock_create()`. In `l2tp_tunnel_sock_create()`, `udp_conf.use_udp6_rx_checksums` is set the same to `cfg.udp6_zero_rx_checksums`. However, if we want the checksum to be ignored, `udp_conf.use_udp6_rx_checksums` should be set to `false`, i.e. be set to the contrary. Similarly, the same should be done to `udp_conf.use_udp6_tx_checksums`. Signed-off-by: Miao Wang <shankerwangmiao@gmail.com> Acked-by: James Chapman <jchapman@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-25l2tp: use nla_put_u64_64bit()Nicolas Dichtel
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-24libnl: nla_put_msecs(): align on a 64-bit areaNicolas Dichtel
nla_data() is now aligned on a 64-bit area. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2016-04-04ipv6: l2tp: fix a potential issue in l2tp_ip6_recvHaishuang Yan
pskb_may_pull() can change skb->data, so we have to load ptr/optr at the right place. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04ipv4: l2tp: fix a potential issue in l2tp_ip_recvHaishuang Yan
pskb_may_pull() can change skb->data, so we have to load ptr/optr at the right place. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>