<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux/skbuff.h, branch v5.17.3</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.17.3</id>
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<updated>2022-04-08T11:59:02Z</updated>
<entry>
<title>net: preserve skb_end_offset() in skb_unclone_keeptruesize()</title>
<updated>2022-04-08T11:59:02Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-02-22T03:21:13Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a903e516f5df44b46d526b403d93e7be1a425538'/>
<id>urn:sha1:a903e516f5df44b46d526b403d93e7be1a425538</id>
<content type='text'>
commit 2b88cba55883eaafbc9b7cbff0b2c7cdba71ed01 upstream.

syzbot found another way to trigger the infamous WARN_ON_ONCE(delta &lt; len)
in skb_try_coalesce() [1]

I was able to root cause the issue to kfence.

When kfence is in action, the following assertion is no longer true:

int size = xxxx;
void *ptr1 = kmalloc(size, gfp);
void *ptr2 = kmalloc(size, gfp);

if (ptr1 &amp;&amp; ptr2)
	ASSERT(ksize(ptr1) == ksize(ptr2));

We attempted to fix these issues in the blamed commits, but forgot
that TCP was possibly shifting data after skb_unclone_keeptruesize()
has been used, notably from tcp_retrans_try_collapse().

So we not only need to keep same skb-&gt;truesize value,
we also need to make sure TCP wont fill new tailroom
that pskb_expand_head() was able to get from a
addr = kmalloc(...) followed by ksize(addr)

Split skb_unclone_keeptruesize() into two parts:

1) Inline skb_unclone_keeptruesize() for the common case,
   when skb is not cloned.

2) Out of line __skb_unclone_keeptruesize() for the 'slow path'.

WARNING: CPU: 1 PID: 6490 at net/core/skbuff.c:5295 skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295
Modules linked in:
CPU: 1 PID: 6490 Comm: syz-executor161 Not tainted 5.17.0-rc4-syzkaller-00229-g4f12b742eb2b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:skb_try_coalesce+0x1235/0x1560 net/core/skbuff.c:5295
Code: bf 01 00 00 00 0f b7 c0 89 c6 89 44 24 20 e8 62 24 4e fa 8b 44 24 20 83 e8 01 0f 85 e5 f0 ff ff e9 87 f4 ff ff e8 cb 20 4e fa &lt;0f&gt; 0b e9 06 f9 ff ff e8 af b2 95 fa e9 69 f0 ff ff e8 95 b2 95 fa
RSP: 0018:ffffc900063af268 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 00000000ffffffd5 RCX: 0000000000000000
RDX: ffff88806fc05700 RSI: ffffffff872abd55 RDI: 0000000000000003
RBP: ffff88806e675500 R08: 00000000ffffffd5 R09: 0000000000000000
R10: ffffffff872ab659 R11: 0000000000000000 R12: ffff88806dd554e8
R13: ffff88806dd9bac0 R14: ffff88806dd9a2c0 R15: 0000000000000155
FS:  00007f18014f9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002000 CR3: 000000006be7a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 &lt;TASK&gt;
 tcp_try_coalesce net/ipv4/tcp_input.c:4651 [inline]
 tcp_try_coalesce+0x393/0x920 net/ipv4/tcp_input.c:4630
 tcp_queue_rcv+0x8a/0x6e0 net/ipv4/tcp_input.c:4914
 tcp_data_queue+0x11fd/0x4bb0 net/ipv4/tcp_input.c:5025
 tcp_rcv_established+0x81e/0x1ff0 net/ipv4/tcp_input.c:5947
 tcp_v4_do_rcv+0x65e/0x980 net/ipv4/tcp_ipv4.c:1719
 sk_backlog_rcv include/net/sock.h:1037 [inline]
 __release_sock+0x134/0x3b0 net/core/sock.c:2779
 release_sock+0x54/0x1b0 net/core/sock.c:3311
 sk_wait_data+0x177/0x450 net/core/sock.c:2821
 tcp_recvmsg_locked+0xe28/0x1fd0 net/ipv4/tcp.c:2457
 tcp_recvmsg+0x137/0x610 net/ipv4/tcp.c:2572
 inet_recvmsg+0x11b/0x5e0 net/ipv4/af_inet.c:850
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:962 [inline]
 ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632
 ___sys_recvmsg+0x127/0x200 net/socket.c:2674
 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: c4777efa751d ("net: add and use skb_unclone_keeptruesize() helper")
Fixes: 097b9146c0e2 ("net: fix up truesize of cloned skb in skb_prepare_for_shift()")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: add skb_set_end_offset() helper</title>
<updated>2022-04-08T11:59:00Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-02-22T03:21:12Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=145bfd63b7acb30b19457d800ac9f6df31da651f'/>
<id>urn:sha1:145bfd63b7acb30b19457d800ac9f6df31da651f</id>
<content type='text'>
commit 763087dab97547230a6807c865a6a5ae53a59247 upstream.

We have multiple places where this helper is convenient,
and plan using it in the following patch.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: socket: rename SKB_DROP_REASON_SOCKET_FILTER</title>
<updated>2022-01-27T16:45:13Z</updated>
<author>
<name>Menglong Dong</name>
<email>imagedong@tencent.com</email>
</author>
<published>2022-01-27T09:13:01Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=364df53c081d93fcfd6b91085ff2650c7f17b3c7'/>
<id>urn:sha1:364df53c081d93fcfd6b91085ff2650c7f17b3c7</id>
<content type='text'>
Rename SKB_DROP_REASON_SOCKET_FILTER, which is used
as the reason of skb drop out of socket filter before
it's part of a released kernel. It will be used for
more protocols than just TCP in future series.

Signed-off-by: Menglong Dong &lt;imagedong@tencent.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/all/20220127091308.91401-2-imagedong@tencent.com/
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2022-01-10T01:00:17Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2022-01-10T00:59:30Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8aaaf2f3af2ae212428f4db1af34214225f5cec3'/>
<id>urn:sha1:8aaaf2f3af2ae212428f4db1af34214225f5cec3</id>
<content type='text'>
Merge in fixes directly in prep for the 5.17 merge window.
No conflicts.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: skb: use kfree_skb_reason() in __udp4_lib_rcv()</title>
<updated>2022-01-10T00:30:35Z</updated>
<author>
<name>Menglong Dong</name>
<email>imagedong@tencent.com</email>
</author>
<published>2022-01-09T06:36:28Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=1c7fab70df085d866a3765955f397ca2b4025b15'/>
<id>urn:sha1:1c7fab70df085d866a3765955f397ca2b4025b15</id>
<content type='text'>
Replace kfree_skb() with kfree_skb_reason() in __udp4_lib_rcv.
New drop reason 'SKB_DROP_REASON_UDP_CSUM' is added for udp csum
error.

Signed-off-by: Menglong Dong &lt;imagedong@tencent.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: skb: use kfree_skb_reason() in tcp_v4_rcv()</title>
<updated>2022-01-10T00:30:34Z</updated>
<author>
<name>Menglong Dong</name>
<email>imagedong@tencent.com</email>
</author>
<published>2022-01-09T06:36:27Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=85125597419aec3aa7b8f3b8713e415f997796f2'/>
<id>urn:sha1:85125597419aec3aa7b8f3b8713e415f997796f2</id>
<content type='text'>
Replace kfree_skb() with kfree_skb_reason() in tcp_v4_rcv(). Following
drop reasons are added:

SKB_DROP_REASON_NO_SOCKET
SKB_DROP_REASON_PKT_TOO_SMALL
SKB_DROP_REASON_TCP_CSUM
SKB_DROP_REASON_TCP_FILTER

After this patch, 'kfree_skb' event will print message like this:

$           TASK-PID     CPU#  |||||  TIMESTAMP  FUNCTION
$              | |         |   |||||     |         |
          &lt;idle&gt;-0       [000] ..s1.    36.113438: kfree_skb: skbaddr=(____ptrval____) protocol=2048 location=(____ptrval____) reason: NO_SOCKET

The reason of skb drop is printed too.

Signed-off-by: Menglong Dong &lt;imagedong@tencent.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: skb: introduce kfree_skb_reason()</title>
<updated>2022-01-10T00:30:34Z</updated>
<author>
<name>Menglong Dong</name>
<email>imagedong@tencent.com</email>
</author>
<published>2022-01-09T06:36:26Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c504e5c2f9648a1e5c2be01e8c3f59d394192bd3'/>
<id>urn:sha1:c504e5c2f9648a1e5c2be01e8c3f59d394192bd3</id>
<content type='text'>
Introduce the interface kfree_skb_reason(), which is able to pass
the reason why the skb is dropped to 'kfree_skb' tracepoint.

Add the 'reason' field to 'trace_kfree_skb', therefor user can get
more detail information about abnormal skb with 'drop_monitor' or
eBPF.

All drop reasons are defined in the enum 'skb_drop_reason', and
they will be print as string in 'kfree_skb' tracepoint in format
of 'reason: XXX'.

( Maybe the reasons should be defined in a uapi header file, so that
user space can use them? )

Signed-off-by: Menglong Dong &lt;imagedong@tencent.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: openvswitch: Fix ct_state nat flags for conns arriving from tc</title>
<updated>2022-01-10T00:24:12Z</updated>
<author>
<name>Paul Blakey</name>
<email>paulb@nvidia.com</email>
</author>
<published>2022-01-06T15:38:04Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=6f022c2ddbcefaee79502ce5386dfe351d457070'/>
<id>urn:sha1:6f022c2ddbcefaee79502ce5386dfe351d457070</id>
<content type='text'>
Netfilter conntrack maintains NAT flags per connection indicating
whether NAT was configured for the connection. Openvswitch maintains
NAT flags on the per packet flow key ct_state field, indicating
whether NAT was actually executed on the packet.

When a packet misses from tc to ovs the conntrack NAT flags are set.
However, NAT was not necessarily executed on the packet because the
connection's state might still be in NEW state. As such, openvswitch
wrongly assumes that NAT was executed and sets an incorrect flow key
NAT flags.

Fix this, by flagging to openvswitch which NAT was actually done in
act_ct via tc_skb_ext and tc_skb_cb to the openvswitch module, so
the packet flow key NAT flags will be correctly set.

Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct")
Signed-off-by: Paul Blakey &lt;paulb@nvidia.com&gt;
Acked-by: Jamal Hadi Salim &lt;jhs@mojatatu.com&gt;
Link: https://lore.kernel.org/r/20220106153804.26451-1-paulb@nvidia.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'for-net-next-2021-12-29' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next</title>
<updated>2021-12-29T22:14:38Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2021-12-29T22:14:38Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e2dfb94f27f778e18e47b0c7ff8679099981073d'/>
<id>urn:sha1:e2dfb94f27f778e18e47b0c7ff8679099981073d</id>
<content type='text'>
Luiz Augusto von Dentz says:

====================
bluetooth-next pull request for net-next:

 - Add support for Foxconn MT7922A
 - Add support for Realtek RTL8852AE
 - Rework HCI event handling to use skb_pull_data

* tag 'for-net-next-2021-12-29' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next: (62 commits)
  Bluetooth: MGMT: Fix spelling mistake "simultanous" -&gt; "simultaneous"
  Bluetooth: vhci: Set HCI_QUIRK_VALID_LE_STATES
  Bluetooth: MGMT: Fix LE simultaneous roles UUID if not supported
  Bluetooth: hci_sync: Add check simultaneous roles support
  Bluetooth: hci_sync: Wait for proper events when connecting LE
  Bluetooth: hci_sync: Add support for waiting specific LE subevents
  Bluetooth: hci_sync: Add hci_le_create_conn_sync
  Bluetooth: hci_event: Use skb_pull_data when processing inquiry results
  Bluetooth: hci_sync: Push sync command cancellation to workqueue
  Bluetooth: hci_qca: Stop IBS timer during BT OFF
  Bluetooth: btusb: Add support for Foxconn MT7922A
  Bluetooth: btintel: Add missing quirks and msft ext for legacy bootloader
  Bluetooth: btusb: Add two more Bluetooth parts for WCN6855
  Bluetooth: L2CAP: Fix using wrong mode
  Bluetooth: hci_sync: Fix not always pausing advertising when necessary
  Bluetooth: mgmt: Make use of mgmt_send_event_skb in MGMT_EV_DEVICE_CONNECTED
  Bluetooth: mgmt: Make use of mgmt_send_event_skb in MGMT_EV_DEVICE_FOUND
  Bluetooth: mgmt: Introduce mgmt_alloc_skb and mgmt_send_event_skb
  Bluetooth: btusb: Return error code when getting patch status failed
  Bluetooth: btusb: Handle download_firmware failure cases
  ...
====================

Link: https://lore.kernel.org/r/20211229211258.2290966-1-luiz.dentz@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2021-12-24T00:09:58Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2021-12-24T00:09:58Z</published>
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<id>urn:sha1:8b3f91332291fa280a56215f5189baca185998f5</id>
<content type='text'>
include/net/sock.h
  commit 8f905c0e7354 ("inet: fully convert sk-&gt;sk_rx_dst to RCU rules")
  commit 43f51df41729 ("net: move early demux fields close to sk_refcnt")
  https://lore.kernel.org/all/20211222141641.0caa0ab3@canb.auug.org.au/

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
</feed>
