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: f3ff8a4d ("ppp: push BKL down into the driver")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add missing rtnl_unlock() in the error path of ppp_create_interface().

Fixes: 58a89eca ("ppp: fix lockdep splat in ppp_dev_uninit()")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ppp_read() and ppp_poll() can be called concurrently with ppp_ioctl().
In this case, ppp_ioctl() might call ppp_ccp_closed(), which may update
ppp->flags while ppp_read() or ppp_poll() is reading it.
The update done by ppp_ccp_closed() isn't atomic due to the bit mask
operation ('ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP)'), so concurrent
readers might get transient values.
Reading incorrect ppp->flags may disturb the 'ppp->flags & SC_LOOP_TRAFFIC'
test in ppp_read() and ppp_poll(), which in turn can lead to improper
decision on whether the PPP unit file is ready for reading or not.

Since ppp_ccp_closed() is protected by the Rx and Tx locks (with
ppp_lock()), taking the Rx lock is enough for ppp_read() and ppp_poll()
to guarantee that ppp_ccp_closed() won't update ppp->flags
concurrently.

The same reasoning applies to ppp->n_channels. The 'n_channels' field
can also be written to concurrently by ppp_ioctl() (through
ppp_connect_channel() or ppp_disconnect_channel()). These writes aren't
atomic (simple increment/decrement), but are protected by both the Rx
and Tx locks (like in the ppp->flags case). So holding the Rx lock
before reading ppp->n_channels also prevents concurrent writes.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

* Split big conditional statement.
  * Check (data.length <= CCP_MAX_OPTION_LENGTH) only once.
  * Don't read ccp_option[1] if not initialised.

Reading uninitialised ccp_option[1] was harmless, because this could
only happen when data.length was 0 or 1. So even then, we couldn't pass
the (ccp_option[1] < 2 || ccp_option[1] > data.length) test anyway.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drop reference on the relay_po socket when __pppoe_xmit() succeeds.
This is already handled correctly in the error path.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Several times already this has been reported as kasan reports caused by
syzkaller and trinity and people always looked at RCU races, but it is
much more simple. :)

In case we bind a pptp socket multiple times, we simply add it to
the callid_sock list but don't remove the old binding. Thus the old
socket stays in the bucket with unused call_id indexes and doesn't get
cleaned up. This causes various forms of kasan reports which were hard
to pinpoint.

Simply don't allow multiple binds and correct error handling in
pptp_bind. Also keep sk_state bits in place in pptp_connect.

Fixes: 00959ade ("PPTP: PPP over IPv4 (Point-to-Point Tunneling Protocol)")
Cc: Dmitry Kozlov <xeb@mail.ru>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Reported-by: NDave Jones <davej@codemonkey.org.uk>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reported-by: NDmitry Vyukov <dvyukov@gmail.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Let user space be aware of the naming scheme used by ppp interfaces
(visible in /sys/class/net/<iface>/name_assign_type).
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Let PPP devices be identified as such in /sys/class/net/<iface>/uevent.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

pppoe_connect() mustn't touch the padt_work field of pppoe sockets
because that work could be already pending.

[   21.473147] BUG: unable to handle kernel NULL pointer dereference at 00000004
[   21.474523] IP: [<c1043177>] process_one_work+0x29/0x31c
[   21.475164] *pde = 00000000
[   21.475513] Oops: 0000 [#1] SMP
[   21.475910] Modules linked in: pppoe pppox ppp_generic slhc crc32c_intel aesni_intel virtio_net xts aes_i586 lrw gf128mul ablk_helper cryptd evdev acpi_cpufreq processor serio_raw button ext4 crc16 mbcache jbd2 virtio_blk virtio_pci virtio_ring virtio
[   21.476168] CPU: 2 PID: 164 Comm: kworker/2:2 Not tainted 4.4.0-rc1 #1
[   21.476168] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[   21.476168] task: f5f83c00 ti: f5e28000 task.ti: f5e28000
[   21.476168] EIP: 0060:[<c1043177>] EFLAGS: 00010046 CPU: 2
[   21.476168] EIP is at process_one_work+0x29/0x31c
[   21.484082] EAX: 00000000 EBX: f678b2a0 ECX: 00000004 EDX: 00000000
[   21.484082] ESI: f6c69940 EDI: f5e29ef0 EBP: f5e29f0c ESP: f5e29edc
[   21.484082]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[   21.484082] CR0: 80050033 CR2: 000000a4 CR3: 317ad000 CR4: 00040690
[   21.484082] Stack:
[   21.484082]  00000000 f6c69950 00000000 f6c69940 c0042338 f5e29f0c c1327945 00000000
[   21.484082]  00000008 f678b2a0 f6c69940 f678b2b8 f5e29f30 c1043984 f5f83c00 f6c69970
[   21.484082]  f678b2a0 c10437d3 f6775e80 f678b2a0 c10437d3 f5e29fac c1047059 f5e29f74
[   21.484082] Call Trace:
[   21.484082]  [<c1327945>] ? _raw_spin_lock_irq+0x28/0x30
[   21.484082]  [<c1043984>] worker_thread+0x1b1/0x244
[   21.484082]  [<c10437d3>] ? rescuer_thread+0x229/0x229
[   21.484082]  [<c10437d3>] ? rescuer_thread+0x229/0x229
[   21.484082]  [<c1047059>] kthread+0x8f/0x94
[   21.484082]  [<c1327a32>] ? _raw_spin_unlock_irq+0x22/0x26
[   21.484082]  [<c1327ee9>] ret_from_kernel_thread+0x21/0x38
[   21.484082]  [<c1046fca>] ? kthread_parkme+0x19/0x19
[   21.496082] Code: 5d c3 55 89 e5 57 56 53 89 c3 83 ec 24 89 d0 89 55 e0 8d 7d e4 e8 6c d8 ff ff b9 04 00 00 00 89 45 d8 8b 43 24 89 45 dc 8b 45 d8 <8b> 40 04 8b 80 e0 00 00 00 c1 e8 05 24 01 88 45 d7 8b 45 e0 8d
[   21.496082] EIP: [<c1043177>] process_one_work+0x29/0x31c SS:ESP 0068:f5e29edc
[   21.496082] CR2: 0000000000000004
[   21.496082] ---[ end trace e362cc9cf10dae89 ]---
Reported-by: NAndrew <nitr0@seti.kr.ua>
Fixes: 287f3a94 ("pppoe: Use workqueue to die properly when a PADT is received")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

* Register PF_PPPOX with pppox module rather than with pppoe,
    so that pppoe doesn't get loaded for any PF_PPPOX socket.

  * Register PX_PROTO_* with standard MODULE_ALIAS_NET_PF_PROTO()
    instead of using pppox's own naming scheme.

  * While there, add auto-loading feature for pptp.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

PPPOX_ZOMBIE is never set anymore.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since 287f3a94 ("pppoe: Use workqueue to die properly when a PADT
is received"), pppoe_disc_rcv() disconnects the socket by scheduling
pppoe_unbind_sock_work(). This is enough to stop socket transmission
and makes the PPPOX_ZOMBIE state uncessary.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: N郭永刚 <guoyonggang@360.cn>
References: http://article.gmane.org/gmane.comp.security.oss.general/17908Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: 2b018d57 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Compute net and store it in a variable in pptp_xmit, so that the value
can be reused the next time it is needed.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is confusing and silly hiding a parameter so modify all of
the callers to pass in the appropriate socket or skb->sk if
no socket is known.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 2b018d57 ("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: [<ffffffffa018c701>] 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:[<ffffffffa018c701>]  [<ffffffffa018c701>] 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]  [<ffffffff812caabe>] sock_release+0x1a/0x75
[  570.144601]  [<ffffffff812cabad>] sock_close+0xd/0x11
[  570.144601]  [<ffffffff811347f5>] __fput+0xff/0x1a5
[  570.144601]  [<ffffffff811348cb>] ____fput+0x9/0xb
[  570.144601]  [<ffffffff81056682>] task_work_run+0x66/0x90
[  570.144601]  [<ffffffff8100189e>] prepare_exit_to_usermode+0x8c/0xa7
[  570.144601]  [<ffffffff81001a26>] syscall_return_slowpath+0x16d/0x19b
[  570.144601]  [<ffffffff813babb1>] 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  [<ffffffffa018c701>] pppoe_release+0x50/0x101 [pppoe]
[  570.144601]  RSP <ffff880036b63e08>
[  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: 2b018d57 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release")
Tested-by: NOleksii Berezhniak <core@irc.lg.ua>
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ppp_dev_uninit() locks all_ppp_mutex while under rtnl mutex protection.
ppp_create_interface() must then lock these mutexes in that same order
to avoid possible deadlock.

[  120.880011] ======================================================
[  120.880011] [ INFO: possible circular locking dependency detected ]
[  120.880011] 4.2.0 #1 Not tainted
[  120.880011] -------------------------------------------------------
[  120.880011] ppp-apitest/15827 is trying to acquire lock:
[  120.880011]  (&pn->all_ppp_mutex){+.+.+.}, at: [<ffffffffa0145f56>] ppp_dev_uninit+0x64/0xb0 [ppp_generic]
[  120.880011]
[  120.880011] but task is already holding lock:
[  120.880011]  (rtnl_mutex){+.+.+.}, at: [<ffffffff812e4255>] rtnl_lock+0x12/0x14
[  120.880011]
[  120.880011] which lock already depends on the new lock.
[  120.880011]
[  120.880011]
[  120.880011] the existing dependency chain (in reverse order) is:
[  120.880011]
[  120.880011] -> #1 (rtnl_mutex){+.+.+.}:
[  120.880011]        [<ffffffff81073a6f>] lock_acquire+0xcf/0x10e
[  120.880011]        [<ffffffff813ab18a>] mutex_lock_nested+0x56/0x341
[  120.880011]        [<ffffffff812e4255>] rtnl_lock+0x12/0x14
[  120.880011]        [<ffffffff812d9d94>] register_netdev+0x11/0x27
[  120.880011]        [<ffffffffa0147b17>] ppp_ioctl+0x289/0xc98 [ppp_generic]
[  120.880011]        [<ffffffff8113b367>] do_vfs_ioctl+0x4ea/0x532
[  120.880011]        [<ffffffff8113b3fd>] SyS_ioctl+0x4e/0x7d
[  120.880011]        [<ffffffff813ad7d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[  120.880011]
[  120.880011] -> #0 (&pn->all_ppp_mutex){+.+.+.}:
[  120.880011]        [<ffffffff8107334e>] __lock_acquire+0xb07/0xe76
[  120.880011]        [<ffffffff81073a6f>] lock_acquire+0xcf/0x10e
[  120.880011]        [<ffffffff813ab18a>] mutex_lock_nested+0x56/0x341
[  120.880011]        [<ffffffffa0145f56>] ppp_dev_uninit+0x64/0xb0 [ppp_generic]
[  120.880011]        [<ffffffff812d5263>] rollback_registered_many+0x19e/0x252
[  120.880011]        [<ffffffff812d5381>] rollback_registered+0x29/0x38
[  120.880011]        [<ffffffff812d53fa>] unregister_netdevice_queue+0x6a/0x77
[  120.880011]        [<ffffffffa0146a94>] ppp_release+0x42/0x79 [ppp_generic]
[  120.880011]        [<ffffffff8112d9f6>] __fput+0xec/0x192
[  120.880011]        [<ffffffff8112dacc>] ____fput+0x9/0xb
[  120.880011]        [<ffffffff8105447a>] task_work_run+0x66/0x80
[  120.880011]        [<ffffffff81001801>] prepare_exit_to_usermode+0x8c/0xa7
[  120.880011]        [<ffffffff81001900>] syscall_return_slowpath+0xe4/0x104
[  120.880011]        [<ffffffff813ad931>] int_ret_from_sys_call+0x25/0x9f
[  120.880011]
[  120.880011] other info that might help us debug this:
[  120.880011]
[  120.880011]  Possible unsafe locking scenario:
[  120.880011]
[  120.880011]        CPU0                    CPU1
[  120.880011]        ----                    ----
[  120.880011]   lock(rtnl_mutex);
[  120.880011]                                lock(&pn->all_ppp_mutex);
[  120.880011]                                lock(rtnl_mutex);
[  120.880011]   lock(&pn->all_ppp_mutex);
[  120.880011]
[  120.880011]  *** DEADLOCK ***

Fixes: 8cb775bc ("ppp: fix device unregistration upon netns deletion")
Reported-by: NSedat Dilek <sedat.dilek@gmail.com>
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Let packets move from one netns to the other at PPP encapsulation and
decapsulation time.

PPP units and channels remain in the netns in which they were
originally created. Only the net_device may move to a different
namespace. Cross netns handling is thus transparent to lower PPP
layers (PPPoE, L2TP, etc.).

PPP devices are automatically unregistered when their netns gets
removed. So read() and poll() on the unit file descriptor will
respectively receive EOF and POLLHUP. Channels aren't affected.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

PPP devices may get automatically unregistered when their network
namespace is getting removed. This happens if the ppp control plane
daemon (e.g. pppd) exits while it is the last user of this namespace.

This leads to several races:

  * ppp_exit_net() may destroy the per namespace idr (pn->units_idr)
    before all file descriptors were released. Successive ppp_release()
    calls may then cleanup PPP devices with ppp_shutdown_interface() and
    try to use the already destroyed idr.

  * Automatic device unregistration may also happen before the
    ppp_release() call for that device gets executed. Once called on
    the file owning the device, ppp_release() will then clean it up and
    try to unregister it a second time.

To fix these issues, operations defined in ppp_shutdown_interface() are
moved to the PPP device's ndo_uninit() callback. This allows PPP
devices to be properly cleaned up by unregister_netdev() and friends.
So checking for ppp->owner is now an accurate test to decide if a PPP
device should be unregistered.

Setting ppp->owner is done in ppp_create_interface(), before device
registration, in order to avoid unprotected modification of this field.

Finally, ppp_exit_net() now starts by unregistering all remaining PPP
devices to ensure that none will get unregistered after the call to
idr_destroy().
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While testing my netfilter changes I noticed several files where
recompiling unncessarily because they unncessarily included
netfilter.h.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

After receiving a PADT and the socket is closed, user space will no
longer drop the reference to the pppoe device.
This leads to errors like this:

[  488.570000] unregister_netdevice: waiting for eth0.2 to become free. Usage count = 2

Fixes: 287f3a94 ("pppoe: Use workqueue to die properly when a PADT is received")
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When PPP is used over a link which does not guarantee packet ordering,
we might get late MPPE packets. This is a problem because MPPE must be
kept synchronized and the current implementation does not drop them and
rekey 4095 times instead of 0, which is wrong.

In order to prevent rekeying about a whole count space times (~ 4095
times), drop packets which are not within the forward 4096/2 window and
increase sanity error counter.
Signed-off-by: NSylvain Rochet <sylvain.rochet@finsecur.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We are going to need sanity error path a little further, rework to be
able to use the sanity error path anywhere in decompressor.
Signed-off-by: NSylvain Rochet <sylvain.rochet@finsecur.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A pppoe session is identified by its session ID and MAC address.
Currently pppoe does not check if the received pkg has the correct
MAC address. This is a problem when the eth I/F is in promisc mode
as then any DST MAC address is accepted.
Signed-off-by: NJoakim Tjernlund <joakim.tjernlund@transmode.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As namespaces are sometimes used with overlapping ip address ranges,
we should also use the namespace as input to the hash to select the ip
fragmentation counter bucket.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a PADT frame is received, the socket may not be in a good state to
close down the PPP interface. The current implementation handles this by
simply blocking all further PPP traffic, and hoping that the lack of traffic
will trigger the user to investigate.

Use schedule_work to get to a process context from which we clear down the
PPP interface, in a fashion analogous to hangup on a TTY-based PPP
interface. This causes pppd to disconnect immediately, and allows tools to
take immediate corrective action.

Note that pppd's rp_pppoe.so plugin has code in it to disable the session
when it disconnects; however, as a consequence of this patch, the session is
already disabled before rp_pppoe.so is asked to disable the session. The
result is a harmless error message:

Failed to disconnect PPPoE socket: 114 Operation already in progress

This message is safe to ignore, as long as the error is 114 Operation
already in progress; in that specific case, it means that the PPPoE session
has already been disabled before pppd tried to disable it.
Signed-off-by: NSimon Farnsworth <simon@farnz.org.uk>
Tested-by: NDan Williams <dcbw@redhat.com>
Tested-by: NChristoph Schulz <develop@kristov.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NIain Douglas <centos@1n6.org.uk>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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 <xeb@mail.ru>
Signed-off-by: NMathias Krause <minipli@googlemail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NStefan Seyfried <stefan.seyfried@googlemail.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".

When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.

Having a helper like this means there will be less places to touch
during that transformation.

Based upon descriptions and patch from Al Viro.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

we used to check for "nobody else could start doing anything with
that opened file" by checking that refcount was 2 or less - one
for descriptor table and one we'd acquired in fget() on the way to
wherever we are.  That was race-prone (somebody else might have
had a reference to descriptor table and do fget() just as we'd
been checking) and it had become flat-out incorrect back when
we switched to fget_light() on those codepaths - unlike fget(),
it doesn't grab an extra reference unless the descriptor table
is shared.  The same change allowed a race-free check, though -
we are safe exactly when refcount is less than 2.

It was a long time ago; pre-2.6.12 for ioctl() (the codepath leading
to ppp one) and 2.6.17 for sendmsg() (netlink one).  OTOH,
netlink hadn't grown that check until 3.9 and ppp used to live
in drivers/net, not drivers/net/ppp until 3.1.  The bug existed
well before that, though, and the same fix used to apply in old
location of file.

Cc: stable@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Testing xmit_more support with netperf and connected UDP sockets,
I found strange dst refcount false sharing.

Current handling of IFF_XMIT_DST_RELEASE is not optimal.

Dropping dst in validate_xmit_skb() is certainly too late in case
packet was queued by cpu X but dequeued by cpu Y

The logical point to take care of drop/force is in __dev_queue_xmit()
before even taking qdisc lock.

As Julian Anastasov pointed out, need for skb_dst() might come from some
packet schedulers or classifiers.

This patch adds new helper to cleanly express needs of various drivers
or qdiscs/classifiers.

Drivers that need skb_dst() in their ndo_start_xmit() should call
following helper in their setup instead of the prior :

	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
->
	netif_keep_dst(dev);

Instead of using a single bit, we use two bits, one being
eventually rebuilt in bonding/team drivers.

The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being
rebuilt in bonding/team. Eventually, we could add something
smarter later.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>