kernel/git/stable/linux.git/net/l2tp, branch linux-4.8.y

l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()

2016-12-10T18:09:38+00:00

[ Upstream commit 32c231164b762dddefa13af5a0101032c70b50ef ] 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: [] dump_stack+0xb3/0x118 lib/dump_stack.c:15 [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:156 [< inline >] print_address_description mm/kasan/report.c:194 [] kasan_report_error+0x1f6/0x4d0 mm/kasan/report.c:283 [< inline >] kasan_report mm/kasan/report.c:303 [] __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 [] l2tp_ip6_close+0x22e/0x290 net/l2tp/l2tp_ip6.c:239 [] inet_release+0xed/0x1c0 net/ipv4/af_inet.c:415 [] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:422 [] sock_release+0x8d/0x1d0 net/socket.c:570 [] sock_close+0x16/0x20 net/socket.c:1017 [] __fput+0x28c/0x780 fs/file_table.c:208 [] ____fput+0x15/0x20 fs/file_table.c:244 [] task_work_run+0xf9/0x170 [] do_exit+0x85e/0x2a00 [] do_group_exit+0x108/0x330 [] get_signal+0x617/0x17a0 kernel/signal.c:2307 [] do_signal+0x7f/0x18f0 [] exit_to_usermode_loop+0xbf/0x150 arch/x86/entry/common.c:156 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:190 [] syscall_return_slowpath+0x1a0/0x1e0 arch/x86/entry/common.c:259 [] entry_SYSCALL_64_fastpath+0xc4/0xc6 Object at ffff8800081b0ec0, in cache L2TP/IPv6 size: 1448 Allocated: PID = 10987 [ 1116.897025] [] save_stack_trace+0x16/0x20 [ 1116.897025] [] save_stack+0x46/0xd0 [ 1116.897025] [] kasan_kmalloc+0xad/0xe0 [ 1116.897025] [] 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] [] kmem_cache_alloc+0xc8/0x2b0 mm/slub.c:2721 [ 1116.897025] [] sk_prot_alloc+0x69/0x2b0 net/core/sock.c:1326 [ 1116.897025] [] sk_alloc+0x38/0xae0 net/core/sock.c:1388 [ 1116.897025] [] inet6_create+0x2d7/0x1000 net/ipv6/af_inet6.c:182 [ 1116.897025] [] __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] [] SyS_socket+0xef/0x1b0 net/socket.c:1203 [ 1116.897025] [] entry_SYSCALL_64_fastpath+0x23/0xc6 Freed: PID = 10987 [ 1116.897025] [] save_stack_trace+0x16/0x20 [ 1116.897025] [] save_stack+0x46/0xd0 [ 1116.897025] [] 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] [] kmem_cache_free+0xc8/0x330 mm/slub.c:2973 [ 1116.897025] [< inline >] sk_prot_free net/core/sock.c:1369 [ 1116.897025] [] __sk_destruct+0x32b/0x4f0 net/core/sock.c:1444 [ 1116.897025] [] sk_destruct+0x44/0x80 net/core/sock.c:1452 [ 1116.897025] [] __sk_free+0x53/0x220 net/core/sock.c:1460 [ 1116.897025] [] sk_free+0x23/0x30 net/core/sock.c:1471 [ 1116.897025] [] sk_common_release+0x28c/0x3e0 ./include/net/sock.h:1589 [ 1116.897025] [] l2tp_ip6_close+0x1fe/0x290 net/l2tp/l2tp_ip6.c:243 [ 1116.897025] [] inet_release+0xed/0x1c0 net/ipv4/af_inet.c:415 [ 1116.897025] [] inet6_release+0x50/0x70 net/ipv6/af_inet6.c:422 [ 1116.897025] [] sock_release+0x8d/0x1d0 net/socket.c:570 [ 1116.897025] [] sock_close+0x16/0x20 net/socket.c:1017 [ 1116.897025] [] __fput+0x28c/0x780 fs/file_table.c:208 [ 1116.897025] [] ____fput+0x15/0x20 fs/file_table.c:244 [ 1116.897025] [] task_work_run+0xf9/0x170 [ 1116.897025] [] do_exit+0x85e/0x2a00 [ 1116.897025] [] do_group_exit+0x108/0x330 [ 1116.897025] [] get_signal+0x617/0x17a0 kernel/signal.c:2307 [ 1116.897025] [] do_signal+0x7f/0x18f0 [ 1116.897025] [] 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] [] syscall_return_slowpath+0x1a0/0x1e0 arch/x86/entry/common.c:259 [ 1116.897025] [] 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 Reported-by: Andrey Konovalov Tested-by: Baozeng Ding Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

l2tp: fix use-after-free during module unload

2016-09-02T18:44:44+00:00

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 Signed-off-by: David S. Miller

l2tp: Fix the connect status check in pppol2tp_getname

2016-08-20T00:55:43+00:00

The sk->sk_state is bits flag, so need use bit operation check instead of value check. Signed-off-by: Gao Feng Tested-by: Guillaume Nault Signed-off-by: David S. Miller

l2tp: Correctly return -EBADF from pppol2tp_getname.

2016-07-26T22:19:46+00:00

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 Signed-off-by: David S. Miller

ipv6: use TOS marks from sockets for routing decision

2016-06-11T22:33:26+00:00

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: Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-06-10T18:52:24+00:00

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

net: add netdev_lockdep_set_classes() helper

2016-06-09T20:28:37+00:00

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 Signed-off-by: David S. Miller

l2tp: fix configuration passed to setup_udp_tunnel_sock()

2016-06-08T18:11:53+00:00

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: [] 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:[] [] 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] [ 72.696530] [] ? udp_gro_receive+0x1c6/0x1f9 [ 72.696530] [] udp4_gro_receive+0x2b5/0x310 [ 72.696530] [] inet_gro_receive+0x4a3/0x4cd [ 72.696530] [] dev_gro_receive+0x584/0x7a3 [ 72.696530] [] ? __lock_is_held+0x29/0x64 [ 72.696530] [] napi_gro_receive+0x124/0x21d [ 72.696530] [] virtnet_receive+0x8df/0x8f6 [virtio_net] [ 72.696530] [] virtnet_poll+0x1d/0x8d [virtio_net] [ 72.696530] [] net_rx_action+0x15b/0x3b9 [ 72.696530] [] __do_softirq+0x216/0x546 [ 72.696530] [] irq_exit+0x49/0xb6 [ 72.696530] [] do_IRQ+0xe2/0xfa [ 72.696530] [] common_interrupt+0x89/0x89 [ 72.696530] [ 72.696530] [] ? trace_hardirqs_on_caller+0x229/0x270 [ 72.696530] [] ? default_idle+0x1c/0x2d [ 72.696530] [] ? default_idle+0x1a/0x2d [ 72.696530] [] arch_cpu_idle+0xa/0xc [ 72.696530] [] default_idle_call+0x1a/0x1c [ 72.696530] [] cpu_startup_entry+0x15b/0x20f [ 72.696530] [] 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 [] 0xffff880033f87d78 [ 72.696530] RSP [ 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 Signed-off-by: David S. Miller

net_sched: transform qdisc running bit into a seqcount

2016-06-07T23:37:13+00:00

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 Cc: Cong Wang Cc: Jamal Hadi Salim Signed-off-by: David S. Miller

net: l2tp: Make l2tp_ip6 namespace aware

2016-05-30T07:03:53+00:00

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 Signed-off-by: David S. Miller