user/sven/linux.git/drivers/net/ppp, branch v3.18.48

ppp: take reference on channels netns

2016-07-12T12:47:40Z

[ Upstream commit 1f461dcdd296eecedaffffc6bae2bfa90bd7eb89 ] Let channels hold a reference on their network namespace. Some channel types, like ppp_async and ppp_synctty, can have their userspace controller running in a different namespace. Therefore they can't rely on them to preclude their netns from being removed from under them. ================================================================== BUG: KASAN: use-after-free in ppp_unregister_channel+0x372/0x3a0 at addr ffff880064e217e0 Read of size 8 by task syz-executor/11581 ============================================================================= BUG net_namespace (Not tainted): kasan: bad access detected ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in copy_net_ns+0x6b/0x1a0 age=92569 cpu=3 pid=6906 [< none >] ___slab_alloc+0x4c7/0x500 kernel/mm/slub.c:2440 [< none >] __slab_alloc+0x4c/0x90 kernel/mm/slub.c:2469 [< inline >] slab_alloc_node kernel/mm/slub.c:2532 [< inline >] slab_alloc kernel/mm/slub.c:2574 [< none >] kmem_cache_alloc+0x23a/0x2b0 kernel/mm/slub.c:2579 [< inline >] kmem_cache_zalloc kernel/include/linux/slab.h:597 [< inline >] net_alloc kernel/net/core/net_namespace.c:325 [< none >] copy_net_ns+0x6b/0x1a0 kernel/net/core/net_namespace.c:360 [< none >] create_new_namespaces+0x2f6/0x610 kernel/kernel/nsproxy.c:95 [< none >] copy_namespaces+0x297/0x320 kernel/kernel/nsproxy.c:150 [< none >] copy_process.part.35+0x1bf4/0x5760 kernel/kernel/fork.c:1451 [< inline >] copy_process kernel/kernel/fork.c:1274 [< none >] _do_fork+0x1bc/0xcb0 kernel/kernel/fork.c:1723 [< inline >] SYSC_clone kernel/kernel/fork.c:1832 [< none >] SyS_clone+0x37/0x50 kernel/kernel/fork.c:1826 [< none >] entry_SYSCALL_64_fastpath+0x16/0x7a kernel/arch/x86/entry/entry_64.S:185 INFO: Freed in net_drop_ns+0x67/0x80 age=575 cpu=2 pid=2631 [< none >] __slab_free+0x1fc/0x320 kernel/mm/slub.c:2650 [< inline >] slab_free kernel/mm/slub.c:2805 [< none >] kmem_cache_free+0x2a0/0x330 kernel/mm/slub.c:2814 [< inline >] net_free kernel/net/core/net_namespace.c:341 [< none >] net_drop_ns+0x67/0x80 kernel/net/core/net_namespace.c:348 [< none >] cleanup_net+0x4e5/0x600 kernel/net/core/net_namespace.c:448 [< none >] process_one_work+0x794/0x1440 kernel/kernel/workqueue.c:2036 [< none >] worker_thread+0xdb/0xfc0 kernel/kernel/workqueue.c:2170 [< none >] kthread+0x23f/0x2d0 kernel/drivers/block/aoe/aoecmd.c:1303 [< none >] ret_from_fork+0x3f/0x70 kernel/arch/x86/entry/entry_64.S:468 INFO: Slab 0xffffea0001938800 objects=3 used=0 fp=0xffff880064e20000 flags=0x5fffc0000004080 INFO: Object 0xffff880064e20000 @offset=0 fp=0xffff880064e24200 CPU: 1 PID: 11581 Comm: syz-executor Tainted: G B 4.4.0+ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 00000000ffffffff ffff8800662c7790 ffffffff8292049d ffff88003e36a300 ffff880064e20000 ffff880064e20000 ffff8800662c77c0 ffffffff816f2054 ffff88003e36a300 ffffea0001938800 ffff880064e20000 0000000000000000 Call Trace: [< inline >] __dump_stack kernel/lib/dump_stack.c:15 [] dump_stack+0x6f/0xa2 kernel/lib/dump_stack.c:50 [] print_trailer+0xf4/0x150 kernel/mm/slub.c:654 [] object_err+0x2f/0x40 kernel/mm/slub.c:661 [< inline >] print_address_description kernel/mm/kasan/report.c:138 [] kasan_report_error+0x215/0x530 kernel/mm/kasan/report.c:236 [< inline >] kasan_report kernel/mm/kasan/report.c:259 [] __asan_report_load8_noabort+0x3e/0x40 kernel/mm/kasan/report.c:280 [< inline >] ? ppp_pernet kernel/include/linux/compiler.h:218 [] ? ppp_unregister_channel+0x372/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392 [< inline >] ppp_pernet kernel/include/linux/compiler.h:218 [] ppp_unregister_channel+0x372/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392 [< inline >] ? ppp_pernet kernel/drivers/net/ppp/ppp_generic.c:293 [] ? ppp_unregister_channel+0xe6/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392 [] ppp_asynctty_close+0xa3/0x130 kernel/drivers/net/ppp/ppp_async.c:241 [] ? async_lcp_peek+0x5b0/0x5b0 kernel/drivers/net/ppp/ppp_async.c:1000 [] tty_ldisc_close.isra.1+0x99/0xe0 kernel/drivers/tty/tty_ldisc.c:478 [] tty_ldisc_kill+0x40/0x170 kernel/drivers/tty/tty_ldisc.c:744 [] tty_ldisc_release+0x1b3/0x260 kernel/drivers/tty/tty_ldisc.c:772 [] tty_release+0xac1/0x13e0 kernel/drivers/tty/tty_io.c:1901 [] ? release_tty+0x320/0x320 kernel/drivers/tty/tty_io.c:1688 [] __fput+0x236/0x780 kernel/fs/file_table.c:208 [] ____fput+0x15/0x20 kernel/fs/file_table.c:244 [] task_work_run+0x16b/0x200 kernel/kernel/task_work.c:115 [< inline >] exit_task_work kernel/include/linux/task_work.h:21 [] do_exit+0x8b5/0x2c60 kernel/kernel/exit.c:750 [] ? debug_check_no_locks_freed+0x290/0x290 kernel/kernel/locking/lockdep.c:4123 [] ? mm_update_next_owner+0x6f0/0x6f0 kernel/kernel/exit.c:357 [] ? __dequeue_signal+0x136/0x470 kernel/kernel/signal.c:550 [] ? recalc_sigpending_tsk+0x13b/0x180 kernel/kernel/signal.c:145 [] do_group_exit+0x108/0x330 kernel/kernel/exit.c:880 [] get_signal+0x5e4/0x14f0 kernel/kernel/signal.c:2307 [< inline >] ? kretprobe_table_lock kernel/kernel/kprobes.c:1113 [] ? kprobe_flush_task+0xb5/0x450 kernel/kernel/kprobes.c:1158 [] do_signal+0x83/0x1c90 kernel/arch/x86/kernel/signal.c:712 [] ? recycle_rp_inst+0x310/0x310 kernel/include/linux/list.h:655 [] ? setup_sigcontext+0x780/0x780 kernel/arch/x86/kernel/signal.c:165 [] ? finish_task_switch+0x424/0x5f0 kernel/kernel/sched/core.c:2692 [< inline >] ? finish_lock_switch kernel/kernel/sched/sched.h:1099 [] ? finish_task_switch+0x120/0x5f0 kernel/kernel/sched/core.c:2678 [< inline >] ? context_switch kernel/kernel/sched/core.c:2807 [] ? __schedule+0x919/0x1bd0 kernel/kernel/sched/core.c:3283 [] exit_to_usermode_loop+0xf1/0x1a0 kernel/arch/x86/entry/common.c:247 [< inline >] prepare_exit_to_usermode kernel/arch/x86/entry/common.c:282 [] syscall_return_slowpath+0x19f/0x210 kernel/arch/x86/entry/common.c:344 [] int_ret_from_sys_call+0x25/0x9f kernel/arch/x86/entry/entry_64.S:281 Memory state around the buggy address: ffff880064e21680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff880064e21700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff880064e21780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff880064e21800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff880064e21880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Fixes: 273ec51dd7ce ("net: ppp_generic - introduce net-namespace functionality v2") Reported-by: Baozeng Ding Signed-off-by: Guillaume Nault Reviewed-by: Cyrill Gorcunov Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ppp: ensure file->private_data can't be overridden

2016-07-12T12:47:38Z

[ Upstream commit e8e56ffd9d2973398b60ece1f1bebb8d67b4d032 ] Locking ppp_mutex must be done before dereferencing file->private_data, otherwise it could be modified before ppp_unattached_ioctl() takes the lock. This could lead ppp_unattached_ioctl() to override ->private_data, thus leaking reference to the ppp_file previously pointed to. v2: lock all ppp_ioctl() instead of just checking private_data in ppp_unattached_ioctl(), to avoid ambiguous behaviour. Fixes: f3ff8a4d80e8 ("ppp: push BKL down into the driver") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ppp, slip: Validate VJ compression slot parameters completely

2016-02-15T20:42:45Z

[ Upstream commit 4ab42d78e37a294ac7bc56901d563c642e03c4ae ] Currently slhc_init() treats out-of-range values of rslots and tslots as equivalent to 0, except that if tslots is too large it will dereference a null pointer (CVE-2015-7799). Add a range-check at the top of the function and make it return an ERR_PTR() on error instead of NULL. Change the callers accordingly. Compile-tested only. Reported-by: 郭永刚 References: http://article.gmane.org/gmane.comp.security.oss.general/17908 Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

pptp: verify sockaddr_len in pptp_bind() and pptp_connect()

2016-01-15T23:41:51Z

[ Upstream commit 09ccfd238e5a0e670d8178cf50180ea81ae09ae1 ] Reported-by: Dmitry Vyukov Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ppp: fix pppoe_dev deletion condition in pppoe_release()

2015-12-03T15:11:30Z

[ Upstream commit 1acea4f6ce1b1c0941438aca75dd2e5c6b09db60 ] We can't rely on PPPOX_ZOMBIE to decide whether to clear po->pppoe_dev. PPPOX_ZOMBIE can be set by pppoe_disc_rcv() even when po->pppoe_dev is NULL. So we have no guarantee that (sk->sk_state & PPPOX_ZOMBIE) implies (po->pppoe_dev != NULL). Since we're releasing a PPPoE socket, we want to release the pppoe_dev if it exists and reset sk_state to PPPOX_DEAD, no matter the previous value of sk_state. So we can just check for po->pppoe_dev and avoid any assumption on sk->sk_state. Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ppp: don't override sk->sk_state in pppoe_flush_dev()

2015-11-13T18:17:05Z

[ Upstream commit e6740165b8f7f06d8caee0fceab3fb9d790a6fed ] Since commit 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release"), pppoe_release() calls dev_put(po->pppoe_dev) if sk is in the PPPOX_ZOMBIE state. But pppoe_flush_dev() can set sk->sk_state to PPPOX_ZOMBIE _and_ reset po->pppoe_dev to NULL. This leads to the following oops: [ 570.140800] BUG: unable to handle kernel NULL pointer dereference at 00000000000004e0 [ 570.142931] IP: [] pppoe_release+0x50/0x101 [pppoe] [ 570.144601] PGD 3d119067 PUD 3dbc1067 PMD 0 [ 570.144601] Oops: 0000 [#1] SMP [ 570.144601] Modules linked in: l2tp_ppp l2tp_netlink l2tp_core ip6_udp_tunnel udp_tunnel pppoe pppox ppp_generic slhc loop crc32c_intel ghash_clmulni_intel jitterentropy_rng sha256_generic hmac drbg ansi_cprng aesni_intel aes_x86_64 ablk_helper cryptd lrw gf128mul glue_helper acpi_cpufreq evdev serio_raw processor button ext4 crc16 mbcache jbd2 virtio_net virtio_blk virtio_pci virtio_ring virtio [ 570.144601] CPU: 1 PID: 15738 Comm: ppp-apitest Not tainted 4.2.0 #1 [ 570.144601] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 570.144601] task: ffff88003d30d600 ti: ffff880036b60000 task.ti: ffff880036b60000 [ 570.144601] RIP: 0010:[] [] pppoe_release+0x50/0x101 [pppoe] [ 570.144601] RSP: 0018:ffff880036b63e08 EFLAGS: 00010202 [ 570.144601] RAX: 0000000000000000 RBX: ffff880034340000 RCX: 0000000000000206 [ 570.144601] RDX: 0000000000000006 RSI: ffff88003d30dd20 RDI: ffff88003d30dd20 [ 570.144601] RBP: ffff880036b63e28 R08: 0000000000000001 R09: 0000000000000000 [ 570.144601] R10: 00007ffee9b50420 R11: ffff880034340078 R12: ffff8800387ec780 [ 570.144601] R13: ffff8800387ec7b0 R14: ffff88003e222aa0 R15: ffff8800387ec7b0 [ 570.144601] FS: 00007f5672f48700(0000) GS:ffff88003fc80000(0000) knlGS:0000000000000000 [ 570.144601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 570.144601] CR2: 00000000000004e0 CR3: 0000000037f7e000 CR4: 00000000000406a0 [ 570.144601] Stack: [ 570.144601] ffffffffa018f240 ffff8800387ec780 ffffffffa018f240 ffff8800387ec7b0 [ 570.144601] ffff880036b63e48 ffffffff812caabe ffff880039e4e000 0000000000000008 [ 570.144601] ffff880036b63e58 ffffffff812cabad ffff880036b63ea8 ffffffff811347f5 [ 570.144601] Call Trace: [ 570.144601] [] sock_release+0x1a/0x75 [ 570.144601] [] sock_close+0xd/0x11 [ 570.144601] [] __fput+0xff/0x1a5 [ 570.144601] [] ____fput+0x9/0xb [ 570.144601] [] task_work_run+0x66/0x90 [ 570.144601] [] prepare_exit_to_usermode+0x8c/0xa7 [ 570.144601] [] syscall_return_slowpath+0x16d/0x19b [ 570.144601] [] int_ret_from_sys_call+0x25/0x9f [ 570.144601] Code: 48 8b 83 c8 01 00 00 a8 01 74 12 48 89 df e8 8b 27 14 e1 b8 f7 ff ff ff e9 b7 00 00 00 8a 43 12 a8 0b 74 1c 48 8b 83 a8 04 00 00 <48> 8b 80 e0 04 00 00 65 ff 08 48 c7 83 a8 04 00 00 00 00 00 00 [ 570.144601] RIP [] pppoe_release+0x50/0x101 [pppoe] [ 570.144601] RSP [ 570.144601] CR2: 00000000000004e0 [ 570.200518] ---[ end trace 46956baf17349563 ]--- pppoe_flush_dev() has no reason to override sk->sk_state with PPPOX_ZOMBIE. pppox_unbind_sock() already sets sk->sk_state to PPPOX_DEAD, which is the correct state given that sk is unbound and po->pppoe_dev is NULL. Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release") Tested-by: Oleksii Berezhniak Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ppp: call skb_checksum_complete_unset in ppp_receive_frame

2015-05-11T11:07:56Z

[ Upstream commit 3dfb05340ec6676e6fc71a9ae87bbbe66d3c2998 ] Call checksum_complete_unset in PPP receive to discard checksum-complete value. PPP does not pull checksum for headers and also modifies packet as in VJ compression. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ppp: deflate: never return len larger than output buffer

2015-02-27T01:49:01Z

[ Upstream commit e2a4800e75780ccf4e6c2487f82b688ba736eb18 ] When we've run out of space in the output buffer to store more data, we will call zlib_deflate with a NULL output buffer until we've consumed remaining input. When this happens, olen contains the size the output buffer would have consumed iff we'd have had enough room. This can later cause skb_over_panic when ppp_generic skb_put()s the returned length. Reported-by: Iain Douglas Signed-off-by: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

pptp: fix stack info leak in pptp_getname()

2014-11-21T03:43:47Z

pptp_getname() only partially initializes the stack variable sa, particularly only fills the pptp part of the sa_addr union. The code thereby discloses 16 bytes of kernel stack memory via getsockname(). Fix this by memset(0)'ing the union before. Cc: Dmitry Kozlov Signed-off-by: Mathias Krause Signed-off-by: David S. Miller

net: ppp: Don't call bpf_prog_create() in ppp_lock

2014-11-11T20:15:03Z

In ppp_ioctl(), bpf_prog_create() is called inside ppp_lock, which eventually calls vmalloc() and hits BUG_ON() in vmalloc.c. This patch works around the problem by moving the allocation outside the lock. The bug was revealed by the recent change in net/core/filter.c, as it allocates via vmalloc() instead of kmalloc() now. Reported-and-tested-by: Stefan Seyfried Signed-off-by: Takashi Iwai Signed-off-by: David S. Miller