<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/net/ppp, branch v3.18.97</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>pppoe: take -&gt;needed_headroom of lower device into account on xmit</title>
<updated>2018-01-31T13:46:15+00:00</updated>
<author>
<name>Guillaume Nault</name>
<email>g.nault@alphalink.fr</email>
</author>
<published>2018-01-22T17:06:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0e4c26c860609df87e52ab334cef36993184727c'/>
<id>0e4c26c860609df87e52ab334cef36993184727c</id>
<content type='text'>
[ Upstream commit 02612bb05e51df8489db5e94d0cf8d1c81f87b0c ]

In pppoe_sendmsg(), reserving dev-&gt;hard_header_len bytes of headroom
was probably fine before the introduction of -&gt;needed_headroom in
commit f5184d267c1a ("net: Allow netdevices to specify needed head/tailroom").

But now, virtual devices typically advertise the size of their overhead
in dev-&gt;needed_headroom, so we must also take it into account in
skb_reserve().
Allocation size of skb is also updated to take dev-&gt;needed_tailroom
into account and replace the arbitrary 32 bytes with the real size of
a PPPoE header.

This issue was discovered by syzbot, who connected a pppoe socket to a
gre device which had dev-&gt;header_ops-&gt;create == ipgre_header and
dev-&gt;hard_header_len == 0. Therefore, PPPoE didn't reserve any
headroom, and dev_hard_header() crashed when ipgre_header() tried to
prepend its header to skb-&gt;data.

skbuff: skb_under_panic: text:000000001d390b3a len:31 put:24
head:00000000d8ed776f data:000000008150e823 tail:0x7 end:0xc0 dev:gre0
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:104!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3670 Comm: syzkaller801466 Not tainted
4.15.0-rc7-next-20180115+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:skb_panic+0x162/0x1f0 net/core/skbuff.c:100
RSP: 0018:ffff8801d9bd7840 EFLAGS: 00010282
RAX: 0000000000000083 RBX: ffff8801d4f083c0 RCX: 0000000000000000
RDX: 0000000000000083 RSI: 1ffff1003b37ae92 RDI: ffffed003b37aefc
RBP: ffff8801d9bd78a8 R08: 1ffff1003b37ae8a R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff86200de0
R13: ffffffff84a981ad R14: 0000000000000018 R15: ffff8801d2d34180
FS:  00000000019c4880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000208bc000 CR3: 00000001d9111001 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  skb_under_panic net/core/skbuff.c:114 [inline]
  skb_push+0xce/0xf0 net/core/skbuff.c:1714
  ipgre_header+0x6d/0x4e0 net/ipv4/ip_gre.c:879
  dev_hard_header include/linux/netdevice.h:2723 [inline]
  pppoe_sendmsg+0x58e/0x8b0 drivers/net/ppp/pppoe.c:890
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:640
  sock_write_iter+0x31a/0x5d0 net/socket.c:909
  call_write_iter include/linux/fs.h:1775 [inline]
  do_iter_readv_writev+0x525/0x7f0 fs/read_write.c:653
  do_iter_write+0x154/0x540 fs/read_write.c:932
  vfs_writev+0x18a/0x340 fs/read_write.c:977
  do_writev+0xfc/0x2a0 fs/read_write.c:1012
  SYSC_writev fs/read_write.c:1085 [inline]
  SyS_writev+0x27/0x30 fs/read_write.c:1082
  entry_SYSCALL_64_fastpath+0x29/0xa0

Admittedly PPPoE shouldn't be allowed to run on non Ethernet-like
interfaces, but reserving space for -&gt;needed_headroom is a more
fundamental issue that needs to be addressed first.

Same problem exists for __pppoe_xmit(), which also needs to take
dev-&gt;needed_headroom into account in skb_cow_head().

Fixes: f5184d267c1a ("net: Allow netdevices to specify needed head/tailroom")
Reported-by: syzbot+ed0838d0fa4c4f2b528e20286e6dc63effc7c14d@syzkaller.appspotmail.com
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Reviewed-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 02612bb05e51df8489db5e94d0cf8d1c81f87b0c ]

In pppoe_sendmsg(), reserving dev-&gt;hard_header_len bytes of headroom
was probably fine before the introduction of -&gt;needed_headroom in
commit f5184d267c1a ("net: Allow netdevices to specify needed head/tailroom").

But now, virtual devices typically advertise the size of their overhead
in dev-&gt;needed_headroom, so we must also take it into account in
skb_reserve().
Allocation size of skb is also updated to take dev-&gt;needed_tailroom
into account and replace the arbitrary 32 bytes with the real size of
a PPPoE header.

This issue was discovered by syzbot, who connected a pppoe socket to a
gre device which had dev-&gt;header_ops-&gt;create == ipgre_header and
dev-&gt;hard_header_len == 0. Therefore, PPPoE didn't reserve any
headroom, and dev_hard_header() crashed when ipgre_header() tried to
prepend its header to skb-&gt;data.

skbuff: skb_under_panic: text:000000001d390b3a len:31 put:24
head:00000000d8ed776f data:000000008150e823 tail:0x7 end:0xc0 dev:gre0
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:104!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3670 Comm: syzkaller801466 Not tainted
4.15.0-rc7-next-20180115+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:skb_panic+0x162/0x1f0 net/core/skbuff.c:100
RSP: 0018:ffff8801d9bd7840 EFLAGS: 00010282
RAX: 0000000000000083 RBX: ffff8801d4f083c0 RCX: 0000000000000000
RDX: 0000000000000083 RSI: 1ffff1003b37ae92 RDI: ffffed003b37aefc
RBP: ffff8801d9bd78a8 R08: 1ffff1003b37ae8a R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff86200de0
R13: ffffffff84a981ad R14: 0000000000000018 R15: ffff8801d2d34180
FS:  00000000019c4880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000208bc000 CR3: 00000001d9111001 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  skb_under_panic net/core/skbuff.c:114 [inline]
  skb_push+0xce/0xf0 net/core/skbuff.c:1714
  ipgre_header+0x6d/0x4e0 net/ipv4/ip_gre.c:879
  dev_hard_header include/linux/netdevice.h:2723 [inline]
  pppoe_sendmsg+0x58e/0x8b0 drivers/net/ppp/pppoe.c:890
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:640
  sock_write_iter+0x31a/0x5d0 net/socket.c:909
  call_write_iter include/linux/fs.h:1775 [inline]
  do_iter_readv_writev+0x525/0x7f0 fs/read_write.c:653
  do_iter_write+0x154/0x540 fs/read_write.c:932
  vfs_writev+0x18a/0x340 fs/read_write.c:977
  do_writev+0xfc/0x2a0 fs/read_write.c:1012
  SYSC_writev fs/read_write.c:1085 [inline]
  SyS_writev+0x27/0x30 fs/read_write.c:1082
  entry_SYSCALL_64_fastpath+0x29/0xa0

Admittedly PPPoE shouldn't be allowed to run on non Ethernet-like
interfaces, but reserving space for -&gt;needed_headroom is a more
fundamental issue that needs to be addressed first.

Same problem exists for __pppoe_xmit(), which also needs to take
dev-&gt;needed_headroom into account in skb_cow_head().

Fixes: f5184d267c1a ("net: Allow netdevices to specify needed head/tailroom")
Reported-by: syzbot+ed0838d0fa4c4f2b528e20286e6dc63effc7c14d@syzkaller.appspotmail.com
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Reviewed-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: Destroy the mutex when cleanup</title>
<updated>2017-12-20T09:01:33+00:00</updated>
<author>
<name>Gao Feng</name>
<email>gfree.wind@vip.163.com</email>
</author>
<published>2017-10-31T10:25:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4c1eff22ffb3df2c626e958b04edb296f57935ef'/>
<id>4c1eff22ffb3df2c626e958b04edb296f57935ef</id>
<content type='text'>
[ Upstream commit f02b2320b27c16b644691267ee3b5c110846f49e ]

The mutex_destroy only makes sense when enable DEBUG_MUTEX. For the
good readbility, it's better to invoke it in exit func when the init
func invokes mutex_init.

Signed-off-by: Gao Feng &lt;gfree.wind@vip.163.com&gt;
Acked-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f02b2320b27c16b644691267ee3b5c110846f49e ]

The mutex_destroy only makes sense when enable DEBUG_MUTEX. For the
good readbility, it's better to invoke it in exit func when the init
func invokes mutex_init.

Signed-off-by: Gao Feng &lt;gfree.wind@vip.163.com&gt;
Acked-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: defer netns reference release for ppp channel</title>
<updated>2017-05-20T12:18:44+00:00</updated>
<author>
<name>WANG Cong</name>
<email>xiyou.wangcong@gmail.com</email>
</author>
<published>2016-07-06T05:12:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bf9ae79d37c4a159bf06f5749b9f59cf3cf642e5'/>
<id>bf9ae79d37c4a159bf06f5749b9f59cf3cf642e5</id>
<content type='text'>
commit 205e1e255c479f3fd77446415706463b282f94e4 upstream.

Matt reported that we have a NULL pointer dereference
in ppp_pernet() from ppp_connect_channel(),
i.e. pch-&gt;chan_net is NULL.

This is due to that a parallel ppp_unregister_channel()
could happen while we are in ppp_connect_channel(), during
which pch-&gt;chan_net set to NULL. Since we need a reference
to net per channel, it makes sense to sync the refcnt
with the life time of the channel, therefore we should
release this reference when we destroy it.

Fixes: 1f461dcdd296 ("ppp: take reference on channels netns")
Reported-by: Matt Bennett &lt;Matt.Bennett@alliedtelesis.co.nz&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: linux-ppp@vger.kernel.org
Cc: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Cc: Cyrill Gorcunov &lt;gorcunov@openvz.org&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Reviewed-by: Cyrill Gorcunov &lt;gorcunov@openvz.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Amit Pundir &lt;amit.pundir@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 205e1e255c479f3fd77446415706463b282f94e4 upstream.

Matt reported that we have a NULL pointer dereference
in ppp_pernet() from ppp_connect_channel(),
i.e. pch-&gt;chan_net is NULL.

This is due to that a parallel ppp_unregister_channel()
could happen while we are in ppp_connect_channel(), during
which pch-&gt;chan_net set to NULL. Since we need a reference
to net per channel, it makes sense to sync the refcnt
with the life time of the channel, therefore we should
release this reference when we destroy it.

Fixes: 1f461dcdd296 ("ppp: take reference on channels netns")
Reported-by: Matt Bennett &lt;Matt.Bennett@alliedtelesis.co.nz&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: linux-ppp@vger.kernel.org
Cc: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Cc: Cyrill Gorcunov &lt;gorcunov@openvz.org&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Reviewed-by: Cyrill Gorcunov &lt;gorcunov@openvz.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Amit Pundir &lt;amit.pundir@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: take reference on channels netns</title>
<updated>2016-07-12T12:47:40+00:00</updated>
<author>
<name>Guillaume Nault</name>
<email>g.nault@alphalink.fr</email>
</author>
<published>2016-03-23T15:38:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a472ae852324f815b61615c3a2dfb80b40a46c22'/>
<id>a472ae852324f815b61615c3a2dfb80b40a46c22</id>
<content type='text'>
[ 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
[&lt;      none      &gt;] ___slab_alloc+0x4c7/0x500 kernel/mm/slub.c:2440
[&lt;      none      &gt;] __slab_alloc+0x4c/0x90 kernel/mm/slub.c:2469
[&lt;     inline     &gt;] slab_alloc_node kernel/mm/slub.c:2532
[&lt;     inline     &gt;] slab_alloc kernel/mm/slub.c:2574
[&lt;      none      &gt;] kmem_cache_alloc+0x23a/0x2b0 kernel/mm/slub.c:2579
[&lt;     inline     &gt;] kmem_cache_zalloc kernel/include/linux/slab.h:597
[&lt;     inline     &gt;] net_alloc kernel/net/core/net_namespace.c:325
[&lt;      none      &gt;] copy_net_ns+0x6b/0x1a0 kernel/net/core/net_namespace.c:360
[&lt;      none      &gt;] create_new_namespaces+0x2f6/0x610 kernel/kernel/nsproxy.c:95
[&lt;      none      &gt;] copy_namespaces+0x297/0x320 kernel/kernel/nsproxy.c:150
[&lt;      none      &gt;] copy_process.part.35+0x1bf4/0x5760 kernel/kernel/fork.c:1451
[&lt;     inline     &gt;] copy_process kernel/kernel/fork.c:1274
[&lt;      none      &gt;] _do_fork+0x1bc/0xcb0 kernel/kernel/fork.c:1723
[&lt;     inline     &gt;] SYSC_clone kernel/kernel/fork.c:1832
[&lt;      none      &gt;] SyS_clone+0x37/0x50 kernel/kernel/fork.c:1826
[&lt;      none      &gt;] 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
[&lt;      none      &gt;] __slab_free+0x1fc/0x320 kernel/mm/slub.c:2650
[&lt;     inline     &gt;] slab_free kernel/mm/slub.c:2805
[&lt;      none      &gt;] kmem_cache_free+0x2a0/0x330 kernel/mm/slub.c:2814
[&lt;     inline     &gt;] net_free kernel/net/core/net_namespace.c:341
[&lt;      none      &gt;] net_drop_ns+0x67/0x80 kernel/net/core/net_namespace.c:348
[&lt;      none      &gt;] cleanup_net+0x4e5/0x600 kernel/net/core/net_namespace.c:448
[&lt;      none      &gt;] process_one_work+0x794/0x1440 kernel/kernel/workqueue.c:2036
[&lt;      none      &gt;] worker_thread+0xdb/0xfc0 kernel/kernel/workqueue.c:2170
[&lt;      none      &gt;] kthread+0x23f/0x2d0 kernel/drivers/block/aoe/aoecmd.c:1303
[&lt;      none      &gt;] 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:
 [&lt;     inline     &gt;] __dump_stack kernel/lib/dump_stack.c:15
 [&lt;ffffffff8292049d&gt;] dump_stack+0x6f/0xa2 kernel/lib/dump_stack.c:50
 [&lt;ffffffff816f2054&gt;] print_trailer+0xf4/0x150 kernel/mm/slub.c:654
 [&lt;ffffffff816f875f&gt;] object_err+0x2f/0x40 kernel/mm/slub.c:661
 [&lt;     inline     &gt;] print_address_description kernel/mm/kasan/report.c:138
 [&lt;ffffffff816fb0c5&gt;] kasan_report_error+0x215/0x530 kernel/mm/kasan/report.c:236
 [&lt;     inline     &gt;] kasan_report kernel/mm/kasan/report.c:259
 [&lt;ffffffff816fb4de&gt;] __asan_report_load8_noabort+0x3e/0x40 kernel/mm/kasan/report.c:280
 [&lt;     inline     &gt;] ? ppp_pernet kernel/include/linux/compiler.h:218
 [&lt;ffffffff83ad71b2&gt;] ? ppp_unregister_channel+0x372/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392
 [&lt;     inline     &gt;] ppp_pernet kernel/include/linux/compiler.h:218
 [&lt;ffffffff83ad71b2&gt;] ppp_unregister_channel+0x372/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392
 [&lt;     inline     &gt;] ? ppp_pernet kernel/drivers/net/ppp/ppp_generic.c:293
 [&lt;ffffffff83ad6f26&gt;] ? ppp_unregister_channel+0xe6/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392
 [&lt;ffffffff83ae18f3&gt;] ppp_asynctty_close+0xa3/0x130 kernel/drivers/net/ppp/ppp_async.c:241
 [&lt;ffffffff83ae1850&gt;] ? async_lcp_peek+0x5b0/0x5b0 kernel/drivers/net/ppp/ppp_async.c:1000
 [&lt;ffffffff82c33239&gt;] tty_ldisc_close.isra.1+0x99/0xe0 kernel/drivers/tty/tty_ldisc.c:478
 [&lt;ffffffff82c332c0&gt;] tty_ldisc_kill+0x40/0x170 kernel/drivers/tty/tty_ldisc.c:744
 [&lt;ffffffff82c34943&gt;] tty_ldisc_release+0x1b3/0x260 kernel/drivers/tty/tty_ldisc.c:772
 [&lt;ffffffff82c1ef21&gt;] tty_release+0xac1/0x13e0 kernel/drivers/tty/tty_io.c:1901
 [&lt;ffffffff82c1e460&gt;] ? release_tty+0x320/0x320 kernel/drivers/tty/tty_io.c:1688
 [&lt;ffffffff8174de36&gt;] __fput+0x236/0x780 kernel/fs/file_table.c:208
 [&lt;ffffffff8174e405&gt;] ____fput+0x15/0x20 kernel/fs/file_table.c:244
 [&lt;ffffffff813595ab&gt;] task_work_run+0x16b/0x200 kernel/kernel/task_work.c:115
 [&lt;     inline     &gt;] exit_task_work kernel/include/linux/task_work.h:21
 [&lt;ffffffff81307105&gt;] do_exit+0x8b5/0x2c60 kernel/kernel/exit.c:750
 [&lt;ffffffff813fdd20&gt;] ? debug_check_no_locks_freed+0x290/0x290 kernel/kernel/locking/lockdep.c:4123
 [&lt;ffffffff81306850&gt;] ? mm_update_next_owner+0x6f0/0x6f0 kernel/kernel/exit.c:357
 [&lt;ffffffff813215e6&gt;] ? __dequeue_signal+0x136/0x470 kernel/kernel/signal.c:550
 [&lt;ffffffff8132067b&gt;] ? recalc_sigpending_tsk+0x13b/0x180 kernel/kernel/signal.c:145
 [&lt;ffffffff81309628&gt;] do_group_exit+0x108/0x330 kernel/kernel/exit.c:880
 [&lt;ffffffff8132b9d4&gt;] get_signal+0x5e4/0x14f0 kernel/kernel/signal.c:2307
 [&lt;     inline     &gt;] ? kretprobe_table_lock kernel/kernel/kprobes.c:1113
 [&lt;ffffffff8151d355&gt;] ? kprobe_flush_task+0xb5/0x450 kernel/kernel/kprobes.c:1158
 [&lt;ffffffff8115f7d3&gt;] do_signal+0x83/0x1c90 kernel/arch/x86/kernel/signal.c:712
 [&lt;ffffffff8151d2a0&gt;] ? recycle_rp_inst+0x310/0x310 kernel/include/linux/list.h:655
 [&lt;ffffffff8115f750&gt;] ? setup_sigcontext+0x780/0x780 kernel/arch/x86/kernel/signal.c:165
 [&lt;ffffffff81380864&gt;] ? finish_task_switch+0x424/0x5f0 kernel/kernel/sched/core.c:2692
 [&lt;     inline     &gt;] ? finish_lock_switch kernel/kernel/sched/sched.h:1099
 [&lt;ffffffff81380560&gt;] ? finish_task_switch+0x120/0x5f0 kernel/kernel/sched/core.c:2678
 [&lt;     inline     &gt;] ? context_switch kernel/kernel/sched/core.c:2807
 [&lt;ffffffff85d794e9&gt;] ? __schedule+0x919/0x1bd0 kernel/kernel/sched/core.c:3283
 [&lt;ffffffff81003901&gt;] exit_to_usermode_loop+0xf1/0x1a0 kernel/arch/x86/entry/common.c:247
 [&lt;     inline     &gt;] prepare_exit_to_usermode kernel/arch/x86/entry/common.c:282
 [&lt;ffffffff810062ef&gt;] syscall_return_slowpath+0x19f/0x210 kernel/arch/x86/entry/common.c:344
 [&lt;ffffffff85d88022&gt;] 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
&gt;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 &lt;sploving1@gmail.com&gt;
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Reviewed-by: Cyrill Gorcunov &lt;gorcunov@openvz.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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
[&lt;      none      &gt;] ___slab_alloc+0x4c7/0x500 kernel/mm/slub.c:2440
[&lt;      none      &gt;] __slab_alloc+0x4c/0x90 kernel/mm/slub.c:2469
[&lt;     inline     &gt;] slab_alloc_node kernel/mm/slub.c:2532
[&lt;     inline     &gt;] slab_alloc kernel/mm/slub.c:2574
[&lt;      none      &gt;] kmem_cache_alloc+0x23a/0x2b0 kernel/mm/slub.c:2579
[&lt;     inline     &gt;] kmem_cache_zalloc kernel/include/linux/slab.h:597
[&lt;     inline     &gt;] net_alloc kernel/net/core/net_namespace.c:325
[&lt;      none      &gt;] copy_net_ns+0x6b/0x1a0 kernel/net/core/net_namespace.c:360
[&lt;      none      &gt;] create_new_namespaces+0x2f6/0x610 kernel/kernel/nsproxy.c:95
[&lt;      none      &gt;] copy_namespaces+0x297/0x320 kernel/kernel/nsproxy.c:150
[&lt;      none      &gt;] copy_process.part.35+0x1bf4/0x5760 kernel/kernel/fork.c:1451
[&lt;     inline     &gt;] copy_process kernel/kernel/fork.c:1274
[&lt;      none      &gt;] _do_fork+0x1bc/0xcb0 kernel/kernel/fork.c:1723
[&lt;     inline     &gt;] SYSC_clone kernel/kernel/fork.c:1832
[&lt;      none      &gt;] SyS_clone+0x37/0x50 kernel/kernel/fork.c:1826
[&lt;      none      &gt;] 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
[&lt;      none      &gt;] __slab_free+0x1fc/0x320 kernel/mm/slub.c:2650
[&lt;     inline     &gt;] slab_free kernel/mm/slub.c:2805
[&lt;      none      &gt;] kmem_cache_free+0x2a0/0x330 kernel/mm/slub.c:2814
[&lt;     inline     &gt;] net_free kernel/net/core/net_namespace.c:341
[&lt;      none      &gt;] net_drop_ns+0x67/0x80 kernel/net/core/net_namespace.c:348
[&lt;      none      &gt;] cleanup_net+0x4e5/0x600 kernel/net/core/net_namespace.c:448
[&lt;      none      &gt;] process_one_work+0x794/0x1440 kernel/kernel/workqueue.c:2036
[&lt;      none      &gt;] worker_thread+0xdb/0xfc0 kernel/kernel/workqueue.c:2170
[&lt;      none      &gt;] kthread+0x23f/0x2d0 kernel/drivers/block/aoe/aoecmd.c:1303
[&lt;      none      &gt;] 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:
 [&lt;     inline     &gt;] __dump_stack kernel/lib/dump_stack.c:15
 [&lt;ffffffff8292049d&gt;] dump_stack+0x6f/0xa2 kernel/lib/dump_stack.c:50
 [&lt;ffffffff816f2054&gt;] print_trailer+0xf4/0x150 kernel/mm/slub.c:654
 [&lt;ffffffff816f875f&gt;] object_err+0x2f/0x40 kernel/mm/slub.c:661
 [&lt;     inline     &gt;] print_address_description kernel/mm/kasan/report.c:138
 [&lt;ffffffff816fb0c5&gt;] kasan_report_error+0x215/0x530 kernel/mm/kasan/report.c:236
 [&lt;     inline     &gt;] kasan_report kernel/mm/kasan/report.c:259
 [&lt;ffffffff816fb4de&gt;] __asan_report_load8_noabort+0x3e/0x40 kernel/mm/kasan/report.c:280
 [&lt;     inline     &gt;] ? ppp_pernet kernel/include/linux/compiler.h:218
 [&lt;ffffffff83ad71b2&gt;] ? ppp_unregister_channel+0x372/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392
 [&lt;     inline     &gt;] ppp_pernet kernel/include/linux/compiler.h:218
 [&lt;ffffffff83ad71b2&gt;] ppp_unregister_channel+0x372/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392
 [&lt;     inline     &gt;] ? ppp_pernet kernel/drivers/net/ppp/ppp_generic.c:293
 [&lt;ffffffff83ad6f26&gt;] ? ppp_unregister_channel+0xe6/0x3a0 kernel/drivers/net/ppp/ppp_generic.c:2392
 [&lt;ffffffff83ae18f3&gt;] ppp_asynctty_close+0xa3/0x130 kernel/drivers/net/ppp/ppp_async.c:241
 [&lt;ffffffff83ae1850&gt;] ? async_lcp_peek+0x5b0/0x5b0 kernel/drivers/net/ppp/ppp_async.c:1000
 [&lt;ffffffff82c33239&gt;] tty_ldisc_close.isra.1+0x99/0xe0 kernel/drivers/tty/tty_ldisc.c:478
 [&lt;ffffffff82c332c0&gt;] tty_ldisc_kill+0x40/0x170 kernel/drivers/tty/tty_ldisc.c:744
 [&lt;ffffffff82c34943&gt;] tty_ldisc_release+0x1b3/0x260 kernel/drivers/tty/tty_ldisc.c:772
 [&lt;ffffffff82c1ef21&gt;] tty_release+0xac1/0x13e0 kernel/drivers/tty/tty_io.c:1901
 [&lt;ffffffff82c1e460&gt;] ? release_tty+0x320/0x320 kernel/drivers/tty/tty_io.c:1688
 [&lt;ffffffff8174de36&gt;] __fput+0x236/0x780 kernel/fs/file_table.c:208
 [&lt;ffffffff8174e405&gt;] ____fput+0x15/0x20 kernel/fs/file_table.c:244
 [&lt;ffffffff813595ab&gt;] task_work_run+0x16b/0x200 kernel/kernel/task_work.c:115
 [&lt;     inline     &gt;] exit_task_work kernel/include/linux/task_work.h:21
 [&lt;ffffffff81307105&gt;] do_exit+0x8b5/0x2c60 kernel/kernel/exit.c:750
 [&lt;ffffffff813fdd20&gt;] ? debug_check_no_locks_freed+0x290/0x290 kernel/kernel/locking/lockdep.c:4123
 [&lt;ffffffff81306850&gt;] ? mm_update_next_owner+0x6f0/0x6f0 kernel/kernel/exit.c:357
 [&lt;ffffffff813215e6&gt;] ? __dequeue_signal+0x136/0x470 kernel/kernel/signal.c:550
 [&lt;ffffffff8132067b&gt;] ? recalc_sigpending_tsk+0x13b/0x180 kernel/kernel/signal.c:145
 [&lt;ffffffff81309628&gt;] do_group_exit+0x108/0x330 kernel/kernel/exit.c:880
 [&lt;ffffffff8132b9d4&gt;] get_signal+0x5e4/0x14f0 kernel/kernel/signal.c:2307
 [&lt;     inline     &gt;] ? kretprobe_table_lock kernel/kernel/kprobes.c:1113
 [&lt;ffffffff8151d355&gt;] ? kprobe_flush_task+0xb5/0x450 kernel/kernel/kprobes.c:1158
 [&lt;ffffffff8115f7d3&gt;] do_signal+0x83/0x1c90 kernel/arch/x86/kernel/signal.c:712
 [&lt;ffffffff8151d2a0&gt;] ? recycle_rp_inst+0x310/0x310 kernel/include/linux/list.h:655
 [&lt;ffffffff8115f750&gt;] ? setup_sigcontext+0x780/0x780 kernel/arch/x86/kernel/signal.c:165
 [&lt;ffffffff81380864&gt;] ? finish_task_switch+0x424/0x5f0 kernel/kernel/sched/core.c:2692
 [&lt;     inline     &gt;] ? finish_lock_switch kernel/kernel/sched/sched.h:1099
 [&lt;ffffffff81380560&gt;] ? finish_task_switch+0x120/0x5f0 kernel/kernel/sched/core.c:2678
 [&lt;     inline     &gt;] ? context_switch kernel/kernel/sched/core.c:2807
 [&lt;ffffffff85d794e9&gt;] ? __schedule+0x919/0x1bd0 kernel/kernel/sched/core.c:3283
 [&lt;ffffffff81003901&gt;] exit_to_usermode_loop+0xf1/0x1a0 kernel/arch/x86/entry/common.c:247
 [&lt;     inline     &gt;] prepare_exit_to_usermode kernel/arch/x86/entry/common.c:282
 [&lt;ffffffff810062ef&gt;] syscall_return_slowpath+0x19f/0x210 kernel/arch/x86/entry/common.c:344
 [&lt;ffffffff85d88022&gt;] 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
&gt;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 &lt;sploving1@gmail.com&gt;
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Reviewed-by: Cyrill Gorcunov &lt;gorcunov@openvz.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: ensure file-&gt;private_data can't be overridden</title>
<updated>2016-07-12T12:47:38+00:00</updated>
<author>
<name>Guillaume Nault</name>
<email>g.nault@alphalink.fr</email>
</author>
<published>2016-03-14T20:17:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6d94f01566e30c87ebd42e1175ade4f648735578'/>
<id>6d94f01566e30c87ebd42e1175ade4f648735578</id>
<content type='text'>
[ Upstream commit e8e56ffd9d2973398b60ece1f1bebb8d67b4d032 ]

Locking ppp_mutex must be done before dereferencing file-&gt;private_data,
otherwise it could be modified before ppp_unattached_ioctl() takes the
lock. This could lead ppp_unattached_ioctl() to override -&gt;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 &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e8e56ffd9d2973398b60ece1f1bebb8d67b4d032 ]

Locking ppp_mutex must be done before dereferencing file-&gt;private_data,
otherwise it could be modified before ppp_unattached_ioctl() takes the
lock. This could lead ppp_unattached_ioctl() to override -&gt;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 &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp, slip: Validate VJ compression slot parameters completely</title>
<updated>2016-02-15T20:42:45+00:00</updated>
<author>
<name>Ben Hutchings</name>
<email>ben@decadent.org.uk</email>
</author>
<published>2015-11-01T16:22:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=82185755d90c8047c6f4b589c39998ff3d4ca3ad'/>
<id>82185755d90c8047c6f4b589c39998ff3d4ca3ad</id>
<content type='text'>
[ 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 &lt;guoyonggang@360.cn&gt;
References: http://article.gmane.org/gmane.comp.security.oss.general/17908
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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 &lt;guoyonggang@360.cn&gt;
References: http://article.gmane.org/gmane.comp.security.oss.general/17908
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>pptp: verify sockaddr_len in pptp_bind() and pptp_connect()</title>
<updated>2016-01-15T23:41:51+00:00</updated>
<author>
<name>WANG Cong</name>
<email>xiyou.wangcong@gmail.com</email>
</author>
<published>2015-12-14T21:48:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=652ed6f6effe13ce2fc0215230517aa01bdbf3e3'/>
<id>652ed6f6effe13ce2fc0215230517aa01bdbf3e3</id>
<content type='text'>
[ Upstream commit 09ccfd238e5a0e670d8178cf50180ea81ae09ae1 ]

Reported-by: Dmitry Vyukov &lt;dvyukov@gmail.com&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 09ccfd238e5a0e670d8178cf50180ea81ae09ae1 ]

Reported-by: Dmitry Vyukov &lt;dvyukov@gmail.com&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: fix pppoe_dev deletion condition in pppoe_release()</title>
<updated>2015-12-03T15:11:30+00:00</updated>
<author>
<name>Guillaume Nault</name>
<email>g.nault@alphalink.fr</email>
</author>
<published>2015-10-22T14:57:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3a98eb90a63c50e72f388e37a2c4a7dd327be369'/>
<id>3a98eb90a63c50e72f388e37a2c4a7dd327be369</id>
<content type='text'>
[ Upstream commit 1acea4f6ce1b1c0941438aca75dd2e5c6b09db60 ]

We can't rely on PPPOX_ZOMBIE to decide whether to clear po-&gt;pppoe_dev.
PPPOX_ZOMBIE can be set by pppoe_disc_rcv() even when po-&gt;pppoe_dev is
NULL. So we have no guarantee that (sk-&gt;sk_state &amp; PPPOX_ZOMBIE) implies
(po-&gt;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-&gt;pppoe_dev and avoid any
assumption on sk-&gt;sk_state.

Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release")
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1acea4f6ce1b1c0941438aca75dd2e5c6b09db60 ]

We can't rely on PPPOX_ZOMBIE to decide whether to clear po-&gt;pppoe_dev.
PPPOX_ZOMBIE can be set by pppoe_disc_rcv() even when po-&gt;pppoe_dev is
NULL. So we have no guarantee that (sk-&gt;sk_state &amp; PPPOX_ZOMBIE) implies
(po-&gt;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-&gt;pppoe_dev and avoid any
assumption on sk-&gt;sk_state.

Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release")
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: don't override sk-&gt;sk_state in pppoe_flush_dev()</title>
<updated>2015-11-13T18:17:05+00:00</updated>
<author>
<name>Guillaume Nault</name>
<email>g.nault@alphalink.fr</email>
</author>
<published>2015-09-30T09:45:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d2c7ba2960397cd255c66e57cf3e8ac2ab81b94d'/>
<id>d2c7ba2960397cd255c66e57cf3e8ac2ab81b94d</id>
<content type='text'>
[ Upstream commit e6740165b8f7f06d8caee0fceab3fb9d790a6fed ]

Since commit 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release"),
pppoe_release() calls dev_put(po-&gt;pppoe_dev) if sk is in the
PPPOX_ZOMBIE state. But pppoe_flush_dev() can set sk-&gt;sk_state to
PPPOX_ZOMBIE _and_ reset po-&gt;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: [&lt;ffffffffa018c701&gt;] 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:[&lt;ffffffffa018c701&gt;]  [&lt;ffffffffa018c701&gt;] 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]  [&lt;ffffffff812caabe&gt;] sock_release+0x1a/0x75
[  570.144601]  [&lt;ffffffff812cabad&gt;] sock_close+0xd/0x11
[  570.144601]  [&lt;ffffffff811347f5&gt;] __fput+0xff/0x1a5
[  570.144601]  [&lt;ffffffff811348cb&gt;] ____fput+0x9/0xb
[  570.144601]  [&lt;ffffffff81056682&gt;] task_work_run+0x66/0x90
[  570.144601]  [&lt;ffffffff8100189e&gt;] prepare_exit_to_usermode+0x8c/0xa7
[  570.144601]  [&lt;ffffffff81001a26&gt;] syscall_return_slowpath+0x16d/0x19b
[  570.144601]  [&lt;ffffffff813babb1&gt;] 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 &lt;48&gt; 8b 80 e0 04 00 00 65 ff 08 48 c7 83 a8 04 00 00 00 00 00 00
[  570.144601] RIP  [&lt;ffffffffa018c701&gt;] pppoe_release+0x50/0x101 [pppoe]
[  570.144601]  RSP &lt;ffff880036b63e08&gt;
[  570.144601] CR2: 00000000000004e0
[  570.200518] ---[ end trace 46956baf17349563 ]---

pppoe_flush_dev() has no reason to override sk-&gt;sk_state with
PPPOX_ZOMBIE. pppox_unbind_sock() already sets sk-&gt;sk_state to
PPPOX_DEAD, which is the correct state given that sk is unbound and
po-&gt;pppoe_dev is NULL.

Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release")
Tested-by: Oleksii Berezhniak &lt;core@irc.lg.ua&gt;
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e6740165b8f7f06d8caee0fceab3fb9d790a6fed ]

Since commit 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release"),
pppoe_release() calls dev_put(po-&gt;pppoe_dev) if sk is in the
PPPOX_ZOMBIE state. But pppoe_flush_dev() can set sk-&gt;sk_state to
PPPOX_ZOMBIE _and_ reset po-&gt;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: [&lt;ffffffffa018c701&gt;] 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:[&lt;ffffffffa018c701&gt;]  [&lt;ffffffffa018c701&gt;] 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]  [&lt;ffffffff812caabe&gt;] sock_release+0x1a/0x75
[  570.144601]  [&lt;ffffffff812cabad&gt;] sock_close+0xd/0x11
[  570.144601]  [&lt;ffffffff811347f5&gt;] __fput+0xff/0x1a5
[  570.144601]  [&lt;ffffffff811348cb&gt;] ____fput+0x9/0xb
[  570.144601]  [&lt;ffffffff81056682&gt;] task_work_run+0x66/0x90
[  570.144601]  [&lt;ffffffff8100189e&gt;] prepare_exit_to_usermode+0x8c/0xa7
[  570.144601]  [&lt;ffffffff81001a26&gt;] syscall_return_slowpath+0x16d/0x19b
[  570.144601]  [&lt;ffffffff813babb1&gt;] 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 &lt;48&gt; 8b 80 e0 04 00 00 65 ff 08 48 c7 83 a8 04 00 00 00 00 00 00
[  570.144601] RIP  [&lt;ffffffffa018c701&gt;] pppoe_release+0x50/0x101 [pppoe]
[  570.144601]  RSP &lt;ffff880036b63e08&gt;
[  570.144601] CR2: 00000000000004e0
[  570.200518] ---[ end trace 46956baf17349563 ]---

pppoe_flush_dev() has no reason to override sk-&gt;sk_state with
PPPOX_ZOMBIE. pppox_unbind_sock() already sets sk-&gt;sk_state to
PPPOX_DEAD, which is the correct state given that sk is unbound and
po-&gt;pppoe_dev is NULL.

Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release")
Tested-by: Oleksii Berezhniak &lt;core@irc.lg.ua&gt;
Signed-off-by: Guillaume Nault &lt;g.nault@alphalink.fr&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ppp: call skb_checksum_complete_unset in ppp_receive_frame</title>
<updated>2015-05-11T11:07:56+00:00</updated>
<author>
<name>Tom Herbert</name>
<email>tom@herbertland.com</email>
</author>
<published>2015-04-20T21:10:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=93cc442175265745f9675a70512a2100ca421119'/>
<id>93cc442175265745f9675a70512a2100ca421119</id>
<content type='text'>
[ 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 &lt;tom@herbertland.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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 &lt;tom@herbertland.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sasha.levin@oracle.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
