<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/net/dccp, branch v4.10-rc6</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v4.10-rc6</id>
<link rel='self' href='http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v4.10-rc6'/>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/'/>
<updated>2017-01-27T15:33:56+00:00</updated>
<entry>
<title>tcp: don't annotate mark on control socket from tcp_v6_send_response()</title>
<updated>2017-01-27T15:33:56+00:00</updated>
<author>
<name>Pablo Neira</name>
<email>pablo@netfilter.org</email>
</author>
<published>2017-01-26T21:56:21+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=92e55f412cffd016cc245a74278cb4d7b89bb3bc'/>
<id>urn:sha1:92e55f412cffd016cc245a74278cb4d7b89bb3bc</id>
<content type='text'>
Unlike ipv4, this control socket is shared by all cpus so we cannot use
it as scratchpad area to annotate the mark that we pass to ip6_xmit().

Add a new parameter to ip6_xmit() to indicate the mark. The SCTP socket
family caches the flowi6 structure in the sctp_transport structure, so
we cannot use to carry the mark unless we later on reset it back, which
I discarded since it looks ugly to me.

Fixes: bf99b4ded5f8 ("tcp: fix mark propagation with fwmark_reflect enabled")
Suggested-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2016-12-03T17:29:53+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2016-12-03T16:46:54+00:00</published>
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<id>urn:sha1:2745529ac7358fdac72e6b388da2e934bd9da82c</id>
<content type='text'>
Couple conflicts resolved here:

1) In the MACB driver, a bug fix to properly initialize the
   RX tail pointer properly overlapped with some changes
   to support variable sized rings.

2) In XGBE we had a "CONFIG_PM" --&gt; "CONFIG_PM_SLEEP" fix
   overlapping with a reorganization of the driver to support
   ACPI, OF, as well as PCI variants of the chip.

3) In 'net' we had several probe error path bug fixes to the
   stmmac driver, meanwhile a lot of this code was cleaned up
   and reorganized in 'net-next'.

4) The cls_flower classifier obtained a helper function in
   'net-next' called __fl_delete() and this overlapped with
   Daniel Borkamann's bug fix to use RCU for object destruction
   in 'net'.  It also overlapped with Jiri's change to guard
   the rhashtable_remove_fast() call with a check against
   tc_skip_sw().

5) In mlx4, a revert bug fix in 'net' overlapped with some
   unrelated changes in 'net-next'.

6) In geneve, a stale header pointer after pskb_expand_head()
   bug fix in 'net' overlapped with a large reorganization of
   the same code in 'net-next'.  Since the 'net-next' code no
   longer had the bug in question, there was nothing to do
   other than to simply take the 'net-next' hunks.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>net/dccp: fix use-after-free in dccp_invalid_packet</title>
<updated>2016-11-30T01:37:26+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-11-28T14:26:49+00:00</published>
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<id>urn:sha1:648f0c28df282636c0c8a7a19ca3ce5fc80a39c3</id>
<content type='text'>
pskb_may_pull() can reallocate skb-&gt;head, we need to reload dh pointer
in dccp_invalid_packet() or risk use after free.

Bug found by Andrey Konovalov using syzkaller.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2016-11-15T15:54:36+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2016-11-15T15:54:36+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=bb598c1b8c9bf56981927dcb8c0dc34b8ff95342'/>
<id>urn:sha1:bb598c1b8c9bf56981927dcb8c0dc34b8ff95342</id>
<content type='text'>
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ipv6: dccp: add missing bind_conflict to dccp_ipv6_mapped</title>
<updated>2016-11-03T20:50:27+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-11-03T15:59:46+00:00</published>
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<id>urn:sha1:990ff4d84408fc55942ca6644f67e361737b3d8e</id>
<content type='text'>
While fuzzing kernel with syzkaller, Andrey reported a nasty crash
in inet6_bind() caused by DCCP lacking a required method.

Fixes: ab1e0a13d7029 ("[SOCK] proto: Add hashinfo member to struct proto")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Tested-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Acked-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ipv6: dccp: fix out of bound access in dccp_v6_err()</title>
<updated>2016-11-03T20:16:51+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-11-03T03:30:48+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=1aa9d1a0e7eefcc61696e147d123453fc0016005'/>
<id>urn:sha1:1aa9d1a0e7eefcc61696e147d123453fc0016005</id>
<content type='text'>
dccp_v6_err() does not use pskb_may_pull() and might access garbage.

We only need 4 bytes at the beginning of the DCCP header, like TCP,
so the 8 bytes pulled in icmpv6_notify() are more than enough.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>dccp: fix out of bound access in dccp_v4_err()</title>
<updated>2016-11-03T20:16:51+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-11-03T02:00:40+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=6706a97fec963d6cb3f7fc2978ec1427b4651214'/>
<id>urn:sha1:6706a97fec963d6cb3f7fc2978ec1427b4651214</id>
<content type='text'>
dccp_v4_err() does not use pskb_may_pull() and might access garbage.

We only need 4 bytes at the beginning of the DCCP header, like TCP,
so the 8 bytes pulled in icmp_socket_deliver() are more than enough.

This patch might allow to process more ICMP messages, as some routers
are still limiting the size of reflected bytes to 28 (RFC 792), instead
of extended lengths (RFC 1812 4.3.2.3)

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>dccp: do not send reset to already closed sockets</title>
<updated>2016-11-03T20:16:51+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-11-03T01:04:24+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=346da62cc186c4b4b1ac59f87f4482b47a047388'/>
<id>urn:sha1:346da62cc186c4b4b1ac59f87f4482b47a047388</id>
<content type='text'>
Andrey reported following warning while fuzzing with syzkaller

WARNING: CPU: 1 PID: 21072 at net/dccp/proto.c:83 dccp_set_state+0x229/0x290
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 21072 Comm: syz-executor Not tainted 4.9.0-rc1+ #293
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffff88003d4c7738 ffffffff81b474f4 0000000000000003 dffffc0000000000
 ffffffff844f8b00 ffff88003d4c7804 ffff88003d4c7800 ffffffff8140c06a
 0000000041b58ab3 ffffffff8479ab7d ffffffff8140beae ffffffff8140cd00
Call Trace:
 [&lt;     inline     &gt;] __dump_stack lib/dump_stack.c:15
 [&lt;ffffffff81b474f4&gt;] dump_stack+0xb3/0x10f lib/dump_stack.c:51
 [&lt;ffffffff8140c06a&gt;] panic+0x1bc/0x39d kernel/panic.c:179
 [&lt;ffffffff8111125c&gt;] __warn+0x1cc/0x1f0 kernel/panic.c:542
 [&lt;ffffffff8111144c&gt;] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [&lt;ffffffff8389e5d9&gt;] dccp_set_state+0x229/0x290 net/dccp/proto.c:83
 [&lt;ffffffff838a0aa2&gt;] dccp_close+0x612/0xc10 net/dccp/proto.c:1016
 [&lt;ffffffff8316bf1f&gt;] inet_release+0xef/0x1c0 net/ipv4/af_inet.c:415
 [&lt;ffffffff82b6e89e&gt;] sock_release+0x8e/0x1d0 net/socket.c:570
 [&lt;ffffffff82b6e9f6&gt;] sock_close+0x16/0x20 net/socket.c:1017
 [&lt;ffffffff815256ad&gt;] __fput+0x29d/0x720 fs/file_table.c:208
 [&lt;ffffffff81525bb5&gt;] ____fput+0x15/0x20 fs/file_table.c:244
 [&lt;ffffffff811727d8&gt;] task_work_run+0xf8/0x170 kernel/task_work.c:116
 [&lt;     inline     &gt;] exit_task_work include/linux/task_work.h:21
 [&lt;ffffffff8111bc53&gt;] do_exit+0x883/0x2ac0 kernel/exit.c:828
 [&lt;ffffffff811221fe&gt;] do_group_exit+0x10e/0x340 kernel/exit.c:931
 [&lt;ffffffff81143c94&gt;] get_signal+0x634/0x15a0 kernel/signal.c:2307
 [&lt;ffffffff81054aad&gt;] do_signal+0x8d/0x1a30 arch/x86/kernel/signal.c:807
 [&lt;ffffffff81003a05&gt;] exit_to_usermode_loop+0xe5/0x130
arch/x86/entry/common.c:156
 [&lt;     inline     &gt;] prepare_exit_to_usermode arch/x86/entry/common.c:190
 [&lt;ffffffff81006298&gt;] syscall_return_slowpath+0x1a8/0x1e0
arch/x86/entry/common.c:259
 [&lt;ffffffff83fc1a62&gt;] entry_SYSCALL_64_fastpath+0xc0/0xc2
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled

Fix this the same way we did for TCP in commit 565b7b2d2e63
("tcp: do not send reset to already closed sockets")

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Tested-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>dccp: do not release listeners too soon</title>
<updated>2016-11-03T20:16:50+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-11-03T00:14:41+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=c3f24cfb3e508c70c26ee8569d537c8ca67a36c6'/>
<id>urn:sha1:c3f24cfb3e508c70c26ee8569d537c8ca67a36c6</id>
<content type='text'>
Andrey Konovalov reported following error while fuzzing with syzkaller :

IPv4: Attempt to release alive inet socket ffff880068e98940
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 3905 Comm: a.out Not tainted 4.9.0-rc3+ #333
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff88006b9e0000 task.stack: ffff880068770000
RIP: 0010:[&lt;ffffffff819ead5f&gt;]  [&lt;ffffffff819ead5f&gt;]
selinux_socket_sock_rcv_skb+0xff/0x6a0 security/selinux/hooks.c:4639
RSP: 0018:ffff8800687771c8  EFLAGS: 00010202
RAX: ffff88006b9e0000 RBX: 1ffff1000d0eee3f RCX: 1ffff1000d1d312a
RDX: 1ffff1000d1d31a6 RSI: dffffc0000000000 RDI: 0000000000000010
RBP: ffff880068777360 R08: 0000000000000000 R09: 0000000000000002
R10: dffffc0000000000 R11: 0000000000000006 R12: ffff880068e98940
R13: 0000000000000002 R14: ffff880068777338 R15: 0000000000000000
FS:  00007f00ff760700(0000) GS:ffff88006cd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020008000 CR3: 000000006a308000 CR4: 00000000000006e0
Stack:
 ffff8800687771e0 ffffffff812508a5 ffff8800686f3168 0000000000000007
 ffff88006ac8cdfc ffff8800665ea500 0000000041b58ab3 ffffffff847b5480
 ffffffff819eac60 ffff88006b9e0860 ffff88006b9e0868 ffff88006b9e07f0
Call Trace:
 [&lt;ffffffff819c8dd5&gt;] security_sock_rcv_skb+0x75/0xb0 security/security.c:1317
 [&lt;ffffffff82c2a9e7&gt;] sk_filter_trim_cap+0x67/0x10e0 net/core/filter.c:81
 [&lt;ffffffff82b81e60&gt;] __sk_receive_skb+0x30/0xa00 net/core/sock.c:460
 [&lt;ffffffff838bbf12&gt;] dccp_v4_rcv+0xdb2/0x1910 net/dccp/ipv4.c:873
 [&lt;ffffffff83069d22&gt;] ip_local_deliver_finish+0x332/0xad0
net/ipv4/ip_input.c:216
 [&lt;     inline     &gt;] NF_HOOK_THRESH ./include/linux/netfilter.h:232
 [&lt;     inline     &gt;] NF_HOOK ./include/linux/netfilter.h:255
 [&lt;ffffffff8306abd2&gt;] ip_local_deliver+0x1c2/0x4b0 net/ipv4/ip_input.c:257
 [&lt;     inline     &gt;] dst_input ./include/net/dst.h:507
 [&lt;ffffffff83068500&gt;] ip_rcv_finish+0x750/0x1c40 net/ipv4/ip_input.c:396
 [&lt;     inline     &gt;] NF_HOOK_THRESH ./include/linux/netfilter.h:232
 [&lt;     inline     &gt;] NF_HOOK ./include/linux/netfilter.h:255
 [&lt;ffffffff8306b82f&gt;] ip_rcv+0x96f/0x12f0 net/ipv4/ip_input.c:487
 [&lt;ffffffff82bd9fb7&gt;] __netif_receive_skb_core+0x1897/0x2a50 net/core/dev.c:4213
 [&lt;ffffffff82bdb19a&gt;] __netif_receive_skb+0x2a/0x170 net/core/dev.c:4251
 [&lt;ffffffff82bdb493&gt;] netif_receive_skb_internal+0x1b3/0x390 net/core/dev.c:4279
 [&lt;ffffffff82bdb6b8&gt;] netif_receive_skb+0x48/0x250 net/core/dev.c:4303
 [&lt;ffffffff8241fc75&gt;] tun_get_user+0xbd5/0x28a0 drivers/net/tun.c:1308
 [&lt;ffffffff82421b5a&gt;] tun_chr_write_iter+0xda/0x190 drivers/net/tun.c:1332
 [&lt;     inline     &gt;] new_sync_write fs/read_write.c:499
 [&lt;ffffffff8151bd44&gt;] __vfs_write+0x334/0x570 fs/read_write.c:512
 [&lt;ffffffff8151f85b&gt;] vfs_write+0x17b/0x500 fs/read_write.c:560
 [&lt;     inline     &gt;] SYSC_write fs/read_write.c:607
 [&lt;ffffffff81523184&gt;] SyS_write+0xd4/0x1a0 fs/read_write.c:599
 [&lt;ffffffff83fc02c1&gt;] entry_SYSCALL_64_fastpath+0x1f/0xc2

It turns out DCCP calls __sk_receive_skb(), and this broke when
lookups no longer took a reference on listeners.

Fix this issue by adding a @refcounted parameter to __sk_receive_skb(),
so that sock_put() is used only when needed.

Fixes: 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Tested-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>tcp/dccp: drop SYN packets if accept queue is full</title>
<updated>2016-10-29T19:09:21+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2016-10-26T16:27:57+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071'/>
<id>urn:sha1:5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071</id>
<content type='text'>
Per listen(fd, backlog) rules, there is really no point accepting a SYN,
sending a SYNACK, and dropping the following ACK packet if accept queue
is full, because application is not draining accept queue fast enough.

This behavior is fooling TCP clients that believe they established a
flow, while there is nothing at server side. They might then send about
10 MSS (if using IW10) that will be dropped anyway while server is under
stress.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Acked-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Acked-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
