<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/ipv4, branch v6.3.6</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>bpf, sockmap: Incorrectly handling copied_seq</title>
<updated>2023-06-05T07:29:42+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2023-05-23T02:56:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f9b4a0b537be7a6e5f002ca64b09dcca9c14e6ed'/>
<id>f9b4a0b537be7a6e5f002ca64b09dcca9c14e6ed</id>
<content type='text'>
[ Upstream commit e5c6de5fa025882babf89cecbed80acf49b987fa ]

The read_skb() logic is incrementing the tcp-&gt;copied_seq which is used for
among other things calculating how many outstanding bytes can be read by
the application. This results in application errors, if the application
does an ioctl(FIONREAD) we return zero because this is calculated from
the copied_seq value.

To fix this we move tcp-&gt;copied_seq accounting into the recv handler so
that we update these when the recvmsg() hook is called and data is in
fact copied into user buffers. This gives an accurate FIONREAD value
as expected and improves ACK handling. Before we were calling the
tcp_rcv_space_adjust() which would update 'number of bytes copied to
user in last RTT' which is wrong for programs returning SK_PASS. The
bytes are only copied to the user when recvmsg is handled.

Doing the fix for recvmsg is straightforward, but fixing redirect and
SK_DROP pkts is a bit tricker. Build a tcp_psock_eat() helper and then
call this from skmsg handlers. This fixes another issue where a broken
socket with a BPF program doing a resubmit could hang the receiver. This
happened because although read_skb() consumed the skb through sock_drop()
it did not update the copied_seq. Now if a single reccv socket is
redirecting to many sockets (for example for lb) the receiver sk will be
hung even though we might expect it to continue. The hang comes from
not updating the copied_seq numbers and memory pressure resulting from
that.

We have a slight layer problem of calling tcp_eat_skb even if its not
a TCP socket. To fix we could refactor and create per type receiver
handlers. I decided this is more work than we want in the fix and we
already have some small tweaks depending on caller that use the
helper skb_bpf_strparser(). So we extend that a bit and always set
the strparser bit when it is in use and then we can gate the
seq_copied updates on this.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-9-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e5c6de5fa025882babf89cecbed80acf49b987fa ]

The read_skb() logic is incrementing the tcp-&gt;copied_seq which is used for
among other things calculating how many outstanding bytes can be read by
the application. This results in application errors, if the application
does an ioctl(FIONREAD) we return zero because this is calculated from
the copied_seq value.

To fix this we move tcp-&gt;copied_seq accounting into the recv handler so
that we update these when the recvmsg() hook is called and data is in
fact copied into user buffers. This gives an accurate FIONREAD value
as expected and improves ACK handling. Before we were calling the
tcp_rcv_space_adjust() which would update 'number of bytes copied to
user in last RTT' which is wrong for programs returning SK_PASS. The
bytes are only copied to the user when recvmsg is handled.

Doing the fix for recvmsg is straightforward, but fixing redirect and
SK_DROP pkts is a bit tricker. Build a tcp_psock_eat() helper and then
call this from skmsg handlers. This fixes another issue where a broken
socket with a BPF program doing a resubmit could hang the receiver. This
happened because although read_skb() consumed the skb through sock_drop()
it did not update the copied_seq. Now if a single reccv socket is
redirecting to many sockets (for example for lb) the receiver sk will be
hung even though we might expect it to continue. The hang comes from
not updating the copied_seq numbers and memory pressure resulting from
that.

We have a slight layer problem of calling tcp_eat_skb even if its not
a TCP socket. To fix we could refactor and create per type receiver
handlers. I decided this is more work than we want in the fix and we
already have some small tweaks depending on caller that use the
helper skb_bpf_strparser(). So we extend that a bit and always set
the strparser bit when it is in use and then we can gate the
seq_copied updates on this.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-9-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf, sockmap: TCP data stall on recv before accept</title>
<updated>2023-06-05T07:29:41+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2023-05-23T02:56:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8818b2229a15d16d9f8844e0ed51ea283d612b78'/>
<id>8818b2229a15d16d9f8844e0ed51ea283d612b78</id>
<content type='text'>
[ Upstream commit ea444185a6bf7da4dd0df1598ee953e4f7174858 ]

A common mechanism to put a TCP socket into the sockmap is to hook the
BPF_SOCK_OPS_{ACTIVE_PASSIVE}_ESTABLISHED_CB event with a BPF program
that can map the socket info to the correct BPF verdict parser. When
the user adds the socket to the map the psock is created and the new
ops are assigned to ensure the verdict program will 'see' the sk_buffs
as they arrive.

Part of this process hooks the sk_data_ready op with a BPF specific
handler to wake up the BPF verdict program when data is ready to read.
The logic is simple enough (posted here for easy reading)

 static void sk_psock_verdict_data_ready(struct sock *sk)
 {
	struct socket *sock = sk-&gt;sk_socket;

	if (unlikely(!sock || !sock-&gt;ops || !sock-&gt;ops-&gt;read_skb))
		return;
	sock-&gt;ops-&gt;read_skb(sk, sk_psock_verdict_recv);
 }

The oversight here is sk-&gt;sk_socket is not assigned until the application
accepts() the new socket. However, its entirely ok for the peer application
to do a connect() followed immediately by sends. The socket on the receiver
is sitting on the backlog queue of the listening socket until its accepted
and the data is queued up. If the peer never accepts the socket or is slow
it will eventually hit data limits and rate limit the session. But,
important for BPF sockmap hooks when this data is received TCP stack does
the sk_data_ready() call but the read_skb() for this data is never called
because sk_socket is missing. The data sits on the sk_receive_queue.

Then once the socket is accepted if we never receive more data from the
peer there will be no further sk_data_ready calls and all the data
is still on the sk_receive_queue(). Then user calls recvmsg after accept()
and for TCP sockets in sockmap we use the tcp_bpf_recvmsg_parser() handler.
The handler checks for data in the sk_msg ingress queue expecting that
the BPF program has already run from the sk_data_ready hook and enqueued
the data as needed. So we are stuck.

To fix do an unlikely check in recvmsg handler for data on the
sk_receive_queue and if it exists wake up data_ready. We have the sock
locked in both read_skb and recvmsg so should avoid having multiple
runners.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-7-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ea444185a6bf7da4dd0df1598ee953e4f7174858 ]

A common mechanism to put a TCP socket into the sockmap is to hook the
BPF_SOCK_OPS_{ACTIVE_PASSIVE}_ESTABLISHED_CB event with a BPF program
that can map the socket info to the correct BPF verdict parser. When
the user adds the socket to the map the psock is created and the new
ops are assigned to ensure the verdict program will 'see' the sk_buffs
as they arrive.

Part of this process hooks the sk_data_ready op with a BPF specific
handler to wake up the BPF verdict program when data is ready to read.
The logic is simple enough (posted here for easy reading)

 static void sk_psock_verdict_data_ready(struct sock *sk)
 {
	struct socket *sock = sk-&gt;sk_socket;

	if (unlikely(!sock || !sock-&gt;ops || !sock-&gt;ops-&gt;read_skb))
		return;
	sock-&gt;ops-&gt;read_skb(sk, sk_psock_verdict_recv);
 }

The oversight here is sk-&gt;sk_socket is not assigned until the application
accepts() the new socket. However, its entirely ok for the peer application
to do a connect() followed immediately by sends. The socket on the receiver
is sitting on the backlog queue of the listening socket until its accepted
and the data is queued up. If the peer never accepts the socket or is slow
it will eventually hit data limits and rate limit the session. But,
important for BPF sockmap hooks when this data is received TCP stack does
the sk_data_ready() call but the read_skb() for this data is never called
because sk_socket is missing. The data sits on the sk_receive_queue.

Then once the socket is accepted if we never receive more data from the
peer there will be no further sk_data_ready calls and all the data
is still on the sk_receive_queue(). Then user calls recvmsg after accept()
and for TCP sockets in sockmap we use the tcp_bpf_recvmsg_parser() handler.
The handler checks for data in the sk_msg ingress queue expecting that
the BPF program has already run from the sk_data_ready hook and enqueued
the data as needed. So we are stuck.

To fix do an unlikely check in recvmsg handler for data on the
sk_receive_queue and if it exists wake up data_ready. We have the sock
locked in both read_skb and recvmsg so should avoid having multiple
runners.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-7-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf, sockmap: Handle fin correctly</title>
<updated>2023-06-05T07:29:41+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2023-05-23T02:56:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cc166415156d757918656dd07170502d07196be3'/>
<id>cc166415156d757918656dd07170502d07196be3</id>
<content type='text'>
[ Upstream commit 901546fd8f9ca4b5c481ce00928ab425ce9aacc0 ]

The sockmap code is returning EAGAIN after a FIN packet is received and no
more data is on the receive queue. Correct behavior is to return 0 to the
user and the user can then close the socket. The EAGAIN causes many apps
to retry which masks the problem. Eventually the socket is evicted from
the sockmap because its released from sockmap sock free handling. The
issue creates a delay and can cause some errors on application side.

To fix this check on sk_msg_recvmsg side if length is zero and FIN flag
is set then set return to zero. A selftest will be added to check this
condition.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Tested-by: William Findlay &lt;will@isovalent.com&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-6-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 901546fd8f9ca4b5c481ce00928ab425ce9aacc0 ]

The sockmap code is returning EAGAIN after a FIN packet is received and no
more data is on the receive queue. Correct behavior is to return 0 to the
user and the user can then close the socket. The EAGAIN causes many apps
to retry which masks the problem. Eventually the socket is evicted from
the sockmap because its released from sockmap sock free handling. The
issue creates a delay and can cause some errors on application side.

To fix this check on sk_msg_recvmsg side if length is zero and FIN flag
is set then set return to zero. A selftest will be added to check this
condition.

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Tested-by: William Findlay &lt;will@isovalent.com&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-6-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf, sockmap: Pass skb ownership through read_skb</title>
<updated>2023-06-05T07:29:39+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2023-05-23T02:56:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=62624be93cceede793842baa6537e2c0246b273c'/>
<id>62624be93cceede793842baa6537e2c0246b273c</id>
<content type='text'>
[ Upstream commit 78fa0d61d97a728d306b0c23d353c0e340756437 ]

The read_skb hook calls consume_skb() now, but this means that if the
recv_actor program wants to use the skb it needs to inc the ref cnt
so that the consume_skb() doesn't kfree the sk_buff.

This is problematic because in some error cases under memory pressure
we may need to linearize the sk_buff from sk_psock_skb_ingress_enqueue().
Then we get this,

 skb_linearize()
   __pskb_pull_tail()
     pskb_expand_head()
       BUG_ON(skb_shared(skb))

Because we incremented users refcnt from sk_psock_verdict_recv() we
hit the bug on with refcnt &gt; 1 and trip it.

To fix lets simply pass ownership of the sk_buff through the skb_read
call. Then we can drop the consume from read_skb handlers and assume
the verdict recv does any required kfree.

Bug found while testing in our CI which runs in VMs that hit memory
constraints rather regularly. William tested TCP read_skb handlers.

[  106.536188] ------------[ cut here ]------------
[  106.536197] kernel BUG at net/core/skbuff.c:1693!
[  106.536479] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[  106.536726] CPU: 3 PID: 1495 Comm: curl Not tainted 5.19.0-rc5 #1
[  106.537023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.16.0-1 04/01/2014
[  106.537467] RIP: 0010:pskb_expand_head+0x269/0x330
[  106.538585] RSP: 0018:ffffc90000138b68 EFLAGS: 00010202
[  106.538839] RAX: 000000000000003f RBX: ffff8881048940e8 RCX: 0000000000000a20
[  106.539186] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff8881048940e8
[  106.539529] RBP: ffffc90000138be8 R08: 00000000e161fd1a R09: 0000000000000000
[  106.539877] R10: 0000000000000018 R11: 0000000000000000 R12: ffff8881048940e8
[  106.540222] R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881048940e8
[  106.540568] FS:  00007f277dde9f00(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
[  106.540954] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  106.541227] CR2: 00007f277eeede64 CR3: 000000000ad3e000 CR4: 00000000000006e0
[  106.541569] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  106.541915] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  106.542255] Call Trace:
[  106.542383]  &lt;IRQ&gt;
[  106.542487]  __pskb_pull_tail+0x4b/0x3e0
[  106.542681]  skb_ensure_writable+0x85/0xa0
[  106.542882]  sk_skb_pull_data+0x18/0x20
[  106.543084]  bpf_prog_b517a65a242018b0_bpf_skskb_http_verdict+0x3a9/0x4aa9
[  106.543536]  ? migrate_disable+0x66/0x80
[  106.543871]  sk_psock_verdict_recv+0xe2/0x310
[  106.544258]  ? sk_psock_write_space+0x1f0/0x1f0
[  106.544561]  tcp_read_skb+0x7b/0x120
[  106.544740]  tcp_data_queue+0x904/0xee0
[  106.544931]  tcp_rcv_established+0x212/0x7c0
[  106.545142]  tcp_v4_do_rcv+0x174/0x2a0
[  106.545326]  tcp_v4_rcv+0xe70/0xf60
[  106.545500]  ip_protocol_deliver_rcu+0x48/0x290
[  106.545744]  ip_local_deliver_finish+0xa7/0x150

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Reported-by: William Findlay &lt;will@isovalent.com&gt;
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Tested-by: William Findlay &lt;will@isovalent.com&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-2-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 78fa0d61d97a728d306b0c23d353c0e340756437 ]

The read_skb hook calls consume_skb() now, but this means that if the
recv_actor program wants to use the skb it needs to inc the ref cnt
so that the consume_skb() doesn't kfree the sk_buff.

This is problematic because in some error cases under memory pressure
we may need to linearize the sk_buff from sk_psock_skb_ingress_enqueue().
Then we get this,

 skb_linearize()
   __pskb_pull_tail()
     pskb_expand_head()
       BUG_ON(skb_shared(skb))

Because we incremented users refcnt from sk_psock_verdict_recv() we
hit the bug on with refcnt &gt; 1 and trip it.

To fix lets simply pass ownership of the sk_buff through the skb_read
call. Then we can drop the consume from read_skb handlers and assume
the verdict recv does any required kfree.

Bug found while testing in our CI which runs in VMs that hit memory
constraints rather regularly. William tested TCP read_skb handlers.

[  106.536188] ------------[ cut here ]------------
[  106.536197] kernel BUG at net/core/skbuff.c:1693!
[  106.536479] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[  106.536726] CPU: 3 PID: 1495 Comm: curl Not tainted 5.19.0-rc5 #1
[  106.537023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.16.0-1 04/01/2014
[  106.537467] RIP: 0010:pskb_expand_head+0x269/0x330
[  106.538585] RSP: 0018:ffffc90000138b68 EFLAGS: 00010202
[  106.538839] RAX: 000000000000003f RBX: ffff8881048940e8 RCX: 0000000000000a20
[  106.539186] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff8881048940e8
[  106.539529] RBP: ffffc90000138be8 R08: 00000000e161fd1a R09: 0000000000000000
[  106.539877] R10: 0000000000000018 R11: 0000000000000000 R12: ffff8881048940e8
[  106.540222] R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881048940e8
[  106.540568] FS:  00007f277dde9f00(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
[  106.540954] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  106.541227] CR2: 00007f277eeede64 CR3: 000000000ad3e000 CR4: 00000000000006e0
[  106.541569] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  106.541915] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  106.542255] Call Trace:
[  106.542383]  &lt;IRQ&gt;
[  106.542487]  __pskb_pull_tail+0x4b/0x3e0
[  106.542681]  skb_ensure_writable+0x85/0xa0
[  106.542882]  sk_skb_pull_data+0x18/0x20
[  106.543084]  bpf_prog_b517a65a242018b0_bpf_skskb_http_verdict+0x3a9/0x4aa9
[  106.543536]  ? migrate_disable+0x66/0x80
[  106.543871]  sk_psock_verdict_recv+0xe2/0x310
[  106.544258]  ? sk_psock_write_space+0x1f0/0x1f0
[  106.544561]  tcp_read_skb+0x7b/0x120
[  106.544740]  tcp_data_queue+0x904/0xee0
[  106.544931]  tcp_rcv_established+0x212/0x7c0
[  106.545142]  tcp_v4_do_rcv+0x174/0x2a0
[  106.545326]  tcp_v4_rcv+0xe70/0xf60
[  106.545500]  ip_protocol_deliver_rcu+0x48/0x290
[  106.545744]  ip_local_deliver_finish+0xa7/0x150

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Reported-by: William Findlay &lt;will@isovalent.com&gt;
Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Tested-by: William Findlay &lt;will@isovalent.com&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20230523025618.113937-2-john.fastabend@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udplite: Fix NULL pointer dereference in __sk_mem_raise_allocated().</title>
<updated>2023-05-30T13:17:24+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2023-05-23T16:33:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f04c8eaf45e7dcdfccba936506b1ec592a369fb9'/>
<id>f04c8eaf45e7dcdfccba936506b1ec592a369fb9</id>
<content type='text'>
commit ad42a35bdfc6d3c0fc4cb4027d7b2757ce665665 upstream.

syzbot reported [0] a null-ptr-deref in sk_get_rmem0() while using
IPPROTO_UDPLITE (0x88):

  14:25:52 executing program 1:
  r0 = socket$inet6(0xa, 0x80002, 0x88)

We had a similar report [1] for probably sk_memory_allocated_add()
in __sk_mem_raise_allocated(), and commit c915fe13cbaa ("udplite: fix
NULL pointer dereference") fixed it by setting .memory_allocated for
udplite_prot and udplitev6_prot.

To fix the variant, we need to set either .sysctl_wmem_offset or
.sysctl_rmem.

Now UDP and UDPLITE share the same value for .memory_allocated, so we
use the same .sysctl_wmem_offset for UDP and UDPLITE.

[0]:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 6829 Comm: syz-executor.1 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
RIP: 0010:sk_get_rmem0 include/net/sock.h:2907 [inline]
RIP: 0010:__sk_mem_raise_allocated+0x806/0x17a0 net/core/sock.c:3006
Code: c1 ea 03 80 3c 02 00 0f 85 23 0f 00 00 48 8b 44 24 08 48 8b 98 38 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 &lt;0f&gt; b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 0f 8d 6f 0a 00 00 8b
RSP: 0018:ffffc90005d7f450 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90004d92000
RDX: 0000000000000000 RSI: ffffffff88066482 RDI: ffffffff8e2ccbb8
RBP: ffff8880173f7000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000030000
R13: 0000000000000001 R14: 0000000000000340 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9800000(0063) knlGS:00000000f7f1cb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002e82f000 CR3: 0000000034ff0000 CR4: 00000000003506f0
Call Trace:
 &lt;TASK&gt;
 __sk_mem_schedule+0x6c/0xe0 net/core/sock.c:3077
 udp_rmem_schedule net/ipv4/udp.c:1539 [inline]
 __udp_enqueue_schedule_skb+0x776/0xb30 net/ipv4/udp.c:1581
 __udpv6_queue_rcv_skb net/ipv6/udp.c:666 [inline]
 udpv6_queue_rcv_one_skb+0xc39/0x16c0 net/ipv6/udp.c:775
 udpv6_queue_rcv_skb+0x194/0xa10 net/ipv6/udp.c:793
 __udp6_lib_mcast_deliver net/ipv6/udp.c:906 [inline]
 __udp6_lib_rcv+0x1bda/0x2bd0 net/ipv6/udp.c:1013
 ip6_protocol_deliver_rcu+0x2e7/0x1250 net/ipv6/ip6_input.c:437
 ip6_input_finish+0x150/0x2f0 net/ipv6/ip6_input.c:482
 NF_HOOK include/linux/netfilter.h:303 [inline]
 NF_HOOK include/linux/netfilter.h:297 [inline]
 ip6_input+0xa0/0xd0 net/ipv6/ip6_input.c:491
 ip6_mc_input+0x40b/0xf50 net/ipv6/ip6_input.c:585
 dst_input include/net/dst.h:468 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 NF_HOOK include/linux/netfilter.h:297 [inline]
 ipv6_rcv+0x250/0x380 net/ipv6/ip6_input.c:309
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5491
 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5605
 netif_receive_skb_internal net/core/dev.c:5691 [inline]
 netif_receive_skb+0x133/0x7a0 net/core/dev.c:5750
 tun_rx_batched+0x4b3/0x7a0 drivers/net/tun.c:1553
 tun_get_user+0x2452/0x39c0 drivers/net/tun.c:1989
 tun_chr_write_iter+0xdf/0x200 drivers/net/tun.c:2035
 call_write_iter include/linux/fs.h:1868 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x945/0xd50 fs/read_write.c:584
 ksys_write+0x12b/0x250 fs/read_write.c:637
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7f21579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 &lt;5d&gt; 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f1c590 EFLAGS: 00000282 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 00000000000000c8 RCX: 0000000020000040
RDX: 0000000000000083 RSI: 00000000f734e000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 &lt;/TASK&gt;
Modules linked in:

Link: https://lore.kernel.org/netdev/CANaxB-yCk8hhP68L4Q2nFOJht8sqgXGGQO2AftpHs0u1xyGG5A@mail.gmail.com/ [1]
Fixes: 850cbaddb52d ("udp: use it's own memory accounting schema")
Reported-by: syzbot+444ca0907e96f7c5e48b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=444ca0907e96f7c5e48b
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://lore.kernel.org/r/20230523163305.66466-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.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>
commit ad42a35bdfc6d3c0fc4cb4027d7b2757ce665665 upstream.

syzbot reported [0] a null-ptr-deref in sk_get_rmem0() while using
IPPROTO_UDPLITE (0x88):

  14:25:52 executing program 1:
  r0 = socket$inet6(0xa, 0x80002, 0x88)

We had a similar report [1] for probably sk_memory_allocated_add()
in __sk_mem_raise_allocated(), and commit c915fe13cbaa ("udplite: fix
NULL pointer dereference") fixed it by setting .memory_allocated for
udplite_prot and udplitev6_prot.

To fix the variant, we need to set either .sysctl_wmem_offset or
.sysctl_rmem.

Now UDP and UDPLITE share the same value for .memory_allocated, so we
use the same .sysctl_wmem_offset for UDP and UDPLITE.

[0]:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 6829 Comm: syz-executor.1 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
RIP: 0010:sk_get_rmem0 include/net/sock.h:2907 [inline]
RIP: 0010:__sk_mem_raise_allocated+0x806/0x17a0 net/core/sock.c:3006
Code: c1 ea 03 80 3c 02 00 0f 85 23 0f 00 00 48 8b 44 24 08 48 8b 98 38 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 &lt;0f&gt; b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 0f 8d 6f 0a 00 00 8b
RSP: 0018:ffffc90005d7f450 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90004d92000
RDX: 0000000000000000 RSI: ffffffff88066482 RDI: ffffffff8e2ccbb8
RBP: ffff8880173f7000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000030000
R13: 0000000000000001 R14: 0000000000000340 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9800000(0063) knlGS:00000000f7f1cb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002e82f000 CR3: 0000000034ff0000 CR4: 00000000003506f0
Call Trace:
 &lt;TASK&gt;
 __sk_mem_schedule+0x6c/0xe0 net/core/sock.c:3077
 udp_rmem_schedule net/ipv4/udp.c:1539 [inline]
 __udp_enqueue_schedule_skb+0x776/0xb30 net/ipv4/udp.c:1581
 __udpv6_queue_rcv_skb net/ipv6/udp.c:666 [inline]
 udpv6_queue_rcv_one_skb+0xc39/0x16c0 net/ipv6/udp.c:775
 udpv6_queue_rcv_skb+0x194/0xa10 net/ipv6/udp.c:793
 __udp6_lib_mcast_deliver net/ipv6/udp.c:906 [inline]
 __udp6_lib_rcv+0x1bda/0x2bd0 net/ipv6/udp.c:1013
 ip6_protocol_deliver_rcu+0x2e7/0x1250 net/ipv6/ip6_input.c:437
 ip6_input_finish+0x150/0x2f0 net/ipv6/ip6_input.c:482
 NF_HOOK include/linux/netfilter.h:303 [inline]
 NF_HOOK include/linux/netfilter.h:297 [inline]
 ip6_input+0xa0/0xd0 net/ipv6/ip6_input.c:491
 ip6_mc_input+0x40b/0xf50 net/ipv6/ip6_input.c:585
 dst_input include/net/dst.h:468 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 NF_HOOK include/linux/netfilter.h:297 [inline]
 ipv6_rcv+0x250/0x380 net/ipv6/ip6_input.c:309
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5491
 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5605
 netif_receive_skb_internal net/core/dev.c:5691 [inline]
 netif_receive_skb+0x133/0x7a0 net/core/dev.c:5750
 tun_rx_batched+0x4b3/0x7a0 drivers/net/tun.c:1553
 tun_get_user+0x2452/0x39c0 drivers/net/tun.c:1989
 tun_chr_write_iter+0xdf/0x200 drivers/net/tun.c:2035
 call_write_iter include/linux/fs.h:1868 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x945/0xd50 fs/read_write.c:584
 ksys_write+0x12b/0x250 fs/read_write.c:637
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7f21579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 &lt;5d&gt; 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f1c590 EFLAGS: 00000282 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 00000000000000c8 RCX: 0000000020000040
RDX: 0000000000000083 RSI: 00000000f734e000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 &lt;/TASK&gt;
Modules linked in:

Link: https://lore.kernel.org/netdev/CANaxB-yCk8hhP68L4Q2nFOJht8sqgXGGQO2AftpHs0u1xyGG5A@mail.gmail.com/ [1]
Fixes: 850cbaddb52d ("udp: use it's own memory accounting schema")
Reported-by: syzbot+444ca0907e96f7c5e48b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=444ca0907e96f7c5e48b
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://lore.kernel.org/r/20230523163305.66466-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv{4,6}/raw: fix output xfrm lookup wrt protocol</title>
<updated>2023-05-30T13:17:21+00:00</updated>
<author>
<name>Nicolas Dichtel</name>
<email>nicolas.dichtel@6wind.com</email>
</author>
<published>2023-05-22T12:08:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=876f62d178b4a24f8b9ddc8e1cd8c1a75fd720dd'/>
<id>876f62d178b4a24f8b9ddc8e1cd8c1a75fd720dd</id>
<content type='text'>
commit 3632679d9e4f879f49949bb5b050e0de553e4739 upstream.

With a raw socket bound to IPPROTO_RAW (ie with hdrincl enabled), the
protocol field of the flow structure, build by raw_sendmsg() /
rawv6_sendmsg()),  is set to IPPROTO_RAW. This breaks the ipsec policy
lookup when some policies are defined with a protocol in the selector.

For ipv6, the sin6_port field from 'struct sockaddr_in6' could be used to
specify the protocol. Just accept all values for IPPROTO_RAW socket.

For ipv4, the sin_port field of 'struct sockaddr_in' could not be used
without breaking backward compatibility (the value of this field was never
checked). Let's add a new kind of control message, so that the userland
could specify which protocol is used.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
CC: stable@vger.kernel.org
Signed-off-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Link: https://lore.kernel.org/r/20230522120820.1319391-1-nicolas.dichtel@6wind.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.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>
commit 3632679d9e4f879f49949bb5b050e0de553e4739 upstream.

With a raw socket bound to IPPROTO_RAW (ie with hdrincl enabled), the
protocol field of the flow structure, build by raw_sendmsg() /
rawv6_sendmsg()),  is set to IPPROTO_RAW. This breaks the ipsec policy
lookup when some policies are defined with a protocol in the selector.

For ipv6, the sin6_port field from 'struct sockaddr_in6' could be used to
specify the protocol. Just accept all values for IPPROTO_RAW socket.

For ipv4, the sin_port field of 'struct sockaddr_in' could not be used
without breaking backward compatibility (the value of this field was never
checked). Let's add a new kind of control message, so that the userland
could specify which protocol is used.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
CC: stable@vger.kernel.org
Signed-off-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Link: https://lore.kernel.org/r/20230522120820.1319391-1-nicolas.dichtel@6wind.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tcp: fix possible sk_priority leak in tcp_v4_send_reset()</title>
<updated>2023-05-24T16:30:14+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-05-11T11:47:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e077f8ff76e725d826954a15f9b239ddc72b9d63'/>
<id>e077f8ff76e725d826954a15f9b239ddc72b9d63</id>
<content type='text'>
[ Upstream commit 1e306ec49a1f206fd2cc89a42fac6e6f592a8cc1 ]

When tcp_v4_send_reset() is called with @sk == NULL,
we do not change ctl_sk-&gt;sk_priority, which could have been
set from a prior invocation.

Change tcp_v4_send_reset() to set sk_priority and sk_mark
fields before calling ip_send_unicast_reply().

This means tcp_v4_send_reset() and tcp_v4_send_ack()
no longer have to clear ctl_sk-&gt;sk_mark after
their call to ip_send_unicast_reply().

Fixes: f6c0f5d209fa ("tcp: honor SO_PRIORITY in TIME_WAIT state")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Antoine Tenart &lt;atenart@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1e306ec49a1f206fd2cc89a42fac6e6f592a8cc1 ]

When tcp_v4_send_reset() is called with @sk == NULL,
we do not change ctl_sk-&gt;sk_priority, which could have been
set from a prior invocation.

Change tcp_v4_send_reset() to set sk_priority and sk_mark
fields before calling ip_send_unicast_reply().

This means tcp_v4_send_reset() and tcp_v4_send_ack()
no longer have to clear ctl_sk-&gt;sk_mark after
their call to ip_send_unicast_reply().

Fixes: f6c0f5d209fa ("tcp: honor SO_PRIORITY in TIME_WAIT state")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Antoine Tenart &lt;atenart@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tcp: add annotations around sk-&gt;sk_shutdown accesses</title>
<updated>2023-05-24T16:29:59+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-05-09T20:36:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d23691497c70db5306d4417a4809858faac1f40f'/>
<id>d23691497c70db5306d4417a4809858faac1f40f</id>
<content type='text'>
[ Upstream commit e14cadfd80d76f01bfaa1a8d745b1db19b57d6be ]

Now sk-&gt;sk_shutdown is no longer a bitfield, we can add
standard READ_ONCE()/WRITE_ONCE() annotations to silence
KCSAN reports like the following:

BUG: KCSAN: data-race in tcp_disconnect / tcp_poll

write to 0xffff88814588582c of 1 bytes by task 3404 on cpu 1:
tcp_disconnect+0x4d6/0xdb0 net/ipv4/tcp.c:3121
__inet_stream_connect+0x5dd/0x6e0 net/ipv4/af_inet.c:715
inet_stream_connect+0x48/0x70 net/ipv4/af_inet.c:727
__sys_connect_file net/socket.c:2001 [inline]
__sys_connect+0x19b/0x1b0 net/socket.c:2018
__do_sys_connect net/socket.c:2028 [inline]
__se_sys_connect net/socket.c:2025 [inline]
__x64_sys_connect+0x41/0x50 net/socket.c:2025
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88814588582c of 1 bytes by task 3374 on cpu 0:
tcp_poll+0x2e6/0x7d0 net/ipv4/tcp.c:562
sock_poll+0x253/0x270 net/socket.c:1383
vfs_poll include/linux/poll.h:88 [inline]
io_poll_check_events io_uring/poll.c:281 [inline]
io_poll_task_func+0x15a/0x820 io_uring/poll.c:333
handle_tw_list io_uring/io_uring.c:1184 [inline]
tctx_task_work+0x1fe/0x4d0 io_uring/io_uring.c:1246
task_work_run+0x123/0x160 kernel/task_work.c:179
get_signal+0xe64/0xff0 kernel/signal.c:2635
arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
__syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x03 -&gt; 0x00

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e14cadfd80d76f01bfaa1a8d745b1db19b57d6be ]

Now sk-&gt;sk_shutdown is no longer a bitfield, we can add
standard READ_ONCE()/WRITE_ONCE() annotations to silence
KCSAN reports like the following:

BUG: KCSAN: data-race in tcp_disconnect / tcp_poll

write to 0xffff88814588582c of 1 bytes by task 3404 on cpu 1:
tcp_disconnect+0x4d6/0xdb0 net/ipv4/tcp.c:3121
__inet_stream_connect+0x5dd/0x6e0 net/ipv4/af_inet.c:715
inet_stream_connect+0x48/0x70 net/ipv4/af_inet.c:727
__sys_connect_file net/socket.c:2001 [inline]
__sys_connect+0x19b/0x1b0 net/socket.c:2018
__do_sys_connect net/socket.c:2028 [inline]
__se_sys_connect net/socket.c:2025 [inline]
__x64_sys_connect+0x41/0x50 net/socket.c:2025
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88814588582c of 1 bytes by task 3374 on cpu 0:
tcp_poll+0x2e6/0x7d0 net/ipv4/tcp.c:562
sock_poll+0x253/0x270 net/socket.c:1383
vfs_poll include/linux/poll.h:88 [inline]
io_poll_check_events io_uring/poll.c:281 [inline]
io_poll_task_func+0x15a/0x820 io_uring/poll.c:333
handle_tw_list io_uring/io_uring.c:1184 [inline]
tctx_task_work+0x1fe/0x4d0 io_uring/io_uring.c:1246
task_work_run+0x123/0x160 kernel/task_work.c:179
get_signal+0xe64/0xff0 kernel/signal.c:2635
arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
__syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x03 -&gt; 0x00

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: deal with most data-races in sk_wait_event()</title>
<updated>2023-05-24T16:29:59+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-05-09T18:29:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a21fb2be5d0fd947ed3328131dc4668fc24da669'/>
<id>a21fb2be5d0fd947ed3328131dc4668fc24da669</id>
<content type='text'>
[ Upstream commit d0ac89f6f9879fae316c155de77b5173b3e2c9c9 ]

__condition is evaluated twice in sk_wait_event() macro.

First invocation is lockless, and reads can race with writes,
as spotted by syzbot.

BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect

write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1:
tcp_disconnect+0x2cd/0xdb0
inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911
__sys_shutdown_sock net/socket.c:2343 [inline]
__sys_shutdown net/socket.c:2355 [inline]
__do_sys_shutdown net/socket.c:2363 [inline]
__se_sys_shutdown+0xf8/0x140 net/socket.c:2361
__x64_sys_shutdown+0x31/0x40 net/socket.c:2361
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0:
sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75
tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484
inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
__sys_sendto+0x246/0x300 net/socket.c:2142
__do_sys_sendto net/socket.c:2154 [inline]
__se_sys_sendto net/socket.c:2150 [inline]
__x64_sys_sendto+0x78/0x90 net/socket.c:2150
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -&gt; 0x00000068

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d0ac89f6f9879fae316c155de77b5173b3e2c9c9 ]

__condition is evaluated twice in sk_wait_event() macro.

First invocation is lockless, and reads can race with writes,
as spotted by syzbot.

BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect

write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1:
tcp_disconnect+0x2cd/0xdb0
inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911
__sys_shutdown_sock net/socket.c:2343 [inline]
__sys_shutdown net/socket.c:2355 [inline]
__do_sys_shutdown net/socket.c:2363 [inline]
__se_sys_shutdown+0xf8/0x140 net/socket.c:2361
__x64_sys_shutdown+0x31/0x40 net/socket.c:2361
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0:
sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75
tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484
inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
__sys_sendto+0x246/0x300 net/socket.c:2142
__do_sys_sendto net/socket.c:2154 [inline]
__se_sys_sendto net/socket.c:2150 [inline]
__x64_sys_sendto+0x78/0x90 net/socket.c:2150
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -&gt; 0x00000068

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv4: Fix potential uninit variable access bug in __ip_make_skb()</title>
<updated>2023-05-11T14:17:22+00:00</updated>
<author>
<name>Ziyang Xuan</name>
<email>william.xuanziyang@huawei.com</email>
</author>
<published>2023-04-20T12:40:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9e3c96aed8fe32907e0a4bca05aad457629a820c'/>
<id>9e3c96aed8fe32907e0a4bca05aad457629a820c</id>
<content type='text'>
[ Upstream commit 99e5acae193e369b71217efe6f1dad42f3f18815 ]

Like commit ea30388baebc ("ipv6: Fix an uninit variable access bug in
__ip6_make_skb()"). icmphdr does not in skb linear region under the
scenario of SOCK_RAW socket. Access icmp_hdr(skb)-&gt;type directly will
trigger the uninit variable access bug.

Use a local variable icmp_type to carry the correct value in different
scenarios.

Fixes: 96793b482540 ("[IPV4]: Add ICMPMsgStats MIB (RFC 4293)")
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Ziyang Xuan &lt;william.xuanziyang@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 99e5acae193e369b71217efe6f1dad42f3f18815 ]

Like commit ea30388baebc ("ipv6: Fix an uninit variable access bug in
__ip6_make_skb()"). icmphdr does not in skb linear region under the
scenario of SOCK_RAW socket. Access icmp_hdr(skb)-&gt;type directly will
trigger the uninit variable access bug.

Use a local variable icmp_type to carry the correct value in different
scenarios.

Fixes: 96793b482540 ("[IPV4]: Add ICMPMsgStats MIB (RFC 4293)")
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Ziyang Xuan &lt;william.xuanziyang@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
