<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include/net, branch v5.15.63</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>9p: Add client parameter to p9_req_put()</title>
<updated>2022-08-17T12:24:07+00:00</updated>
<author>
<name>Kent Overstreet</name>
<email>kent.overstreet@gmail.com</email>
</author>
<published>2022-07-04T01:08:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=273c16d93f865fb25af389898b7011832f80c26c'/>
<id>273c16d93f865fb25af389898b7011832f80c26c</id>
<content type='text'>
[ Upstream commit 8b11ff098af42b1fa57fc817daadd53c8b244a0c ]

This is to aid in adding mempools, in the next patch.

Link: https://lkml.kernel.org/r/20220704014243.153050-2-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: Eric Van Hensbergen &lt;ericvh@gmail.com&gt;
Cc: Latchesar Ionkov &lt;lucho@ionkov.net&gt;
Signed-off-by: Dominique Martinet &lt;asmadeus@codewreck.org&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 8b11ff098af42b1fa57fc817daadd53c8b244a0c ]

This is to aid in adding mempools, in the next patch.

Link: https://lkml.kernel.org/r/20220704014243.153050-2-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: Eric Van Hensbergen &lt;ericvh@gmail.com&gt;
Cc: Latchesar Ionkov &lt;lucho@ionkov.net&gt;
Signed-off-by: Dominique Martinet &lt;asmadeus@codewreck.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>9p: Drop kref usage</title>
<updated>2022-08-17T12:24:07+00:00</updated>
<author>
<name>Kent Overstreet</name>
<email>kent.overstreet@gmail.com</email>
</author>
<published>2022-07-04T01:02:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3ac76cdab956fd443551ebb39a0c78e5c6c94061'/>
<id>3ac76cdab956fd443551ebb39a0c78e5c6c94061</id>
<content type='text'>
[ Upstream commit 6cda12864cb0f99810a5809e11e3ee5b102c9a47 ]

An upcoming patch is going to require passing the client through
p9_req_put() -&gt; p9_req_free(), but that's awkward with the kref
indirection - so this patch switches to using refcount_t directly.

Link: https://lkml.kernel.org/r/20220704014243.153050-1-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: Eric Van Hensbergen &lt;ericvh@gmail.com&gt;
Cc: Latchesar Ionkov &lt;lucho@ionkov.net&gt;
Signed-off-by: Dominique Martinet &lt;asmadeus@codewreck.org&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 6cda12864cb0f99810a5809e11e3ee5b102c9a47 ]

An upcoming patch is going to require passing the client through
p9_req_put() -&gt; p9_req_free(), but that's awkward with the kref
indirection - so this patch switches to using refcount_t directly.

Link: https://lkml.kernel.org/r/20220704014243.153050-1-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: Eric Van Hensbergen &lt;ericvh@gmail.com&gt;
Cc: Latchesar Ionkov &lt;lucho@ionkov.net&gt;
Signed-off-by: Dominique Martinet &lt;asmadeus@codewreck.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>9p: fix a bunch of checkpatch warnings</title>
<updated>2022-08-17T12:24:07+00:00</updated>
<author>
<name>Dominique Martinet</name>
<email>asmadeus@codewreck.org</email>
</author>
<published>2021-11-02T13:16:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=eb3eed52a77cc565cfbc4276e159a27c435558b4'/>
<id>eb3eed52a77cc565cfbc4276e159a27c435558b4</id>
<content type='text'>
[ Upstream commit 6e195b0f7c8e50927fa31946369c22a0534ec7e2 ]

Sohaib Mohamed started a serie of tiny and incomplete checkpatch fixes but
seemingly stopped halfway -- take over and do most of it.
This is still missing net/9p/trans* and net/9p/protocol.c for a later
time...

Link: http://lkml.kernel.org/r/20211102134608.1588018-3-dominique.martinet@atmark-techno.com
Signed-off-by: Dominique Martinet &lt;asmadeus@codewreck.org&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 6e195b0f7c8e50927fa31946369c22a0534ec7e2 ]

Sohaib Mohamed started a serie of tiny and incomplete checkpatch fixes but
seemingly stopped halfway -- take over and do most of it.
This is still missing net/9p/trans* and net/9p/protocol.c for a later
time...

Link: http://lkml.kernel.org/r/20211102134608.1588018-3-dominique.martinet@atmark-techno.com
Signed-off-by: Dominique Martinet &lt;asmadeus@codewreck.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: allow unbound socket for packets in VRF when tcp_l3mdev_accept set</title>
<updated>2022-08-17T12:23:36+00:00</updated>
<author>
<name>Mike Manning</name>
<email>mvrmanning@gmail.com</email>
</author>
<published>2022-07-25T18:14:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=51dd6d3beb7fdace8c66b50a7dc72a723cf9ad8f'/>
<id>51dd6d3beb7fdace8c66b50a7dc72a723cf9ad8f</id>
<content type='text'>
[ Upstream commit 944fd1aeacb627fa617f85f8e5a34f7ae8ea4d8e ]

The commit 3c82a21f4320 ("net: allow binding socket in a VRF when
there's an unbound socket") changed the inet socket lookup to avoid
packets in a VRF from matching an unbound socket. This is to ensure the
necessary isolation between the default and other VRFs for routing and
forwarding. VRF-unaware processes running in the default VRF cannot
access another VRF and have to be run with 'ip vrf exec &lt;vrf&gt;'. This is
to be expected with tcp_l3mdev_accept disabled, but could be reallowed
when this sysctl option is enabled. So instead of directly checking dif
and sdif in inet[6]_match, here call inet_sk_bound_dev_eq(). This
allows a match on unbound socket for non-zero sdif i.e. for packets in
a VRF, if tcp_l3mdev_accept is enabled.

Fixes: 3c82a21f4320 ("net: allow binding socket in a VRF when there's an unbound socket")
Signed-off-by: Mike Manning &lt;mvrmanning@gmail.com&gt;
Link: https://lore.kernel.org/netdev/a54c149aed38fded2d3b5fdb1a6c89e36a083b74.camel@lasnet.de/
Reviewed-by: David Ahern &lt;dsahern@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 944fd1aeacb627fa617f85f8e5a34f7ae8ea4d8e ]

The commit 3c82a21f4320 ("net: allow binding socket in a VRF when
there's an unbound socket") changed the inet socket lookup to avoid
packets in a VRF from matching an unbound socket. This is to ensure the
necessary isolation between the default and other VRFs for routing and
forwarding. VRF-unaware processes running in the default VRF cannot
access another VRF and have to be run with 'ip vrf exec &lt;vrf&gt;'. This is
to be expected with tcp_l3mdev_accept disabled, but could be reallowed
when this sysctl option is enabled. So instead of directly checking dif
and sdif in inet[6]_match, here call inet_sk_bound_dev_eq(). This
allows a match on unbound socket for non-zero sdif i.e. for packets in
a VRF, if tcp_l3mdev_accept is enabled.

Fixes: 3c82a21f4320 ("net: allow binding socket in a VRF when there's an unbound socket")
Signed-off-by: Mike Manning &lt;mvrmanning@gmail.com&gt;
Link: https://lore.kernel.org/netdev/a54c149aed38fded2d3b5fdb1a6c89e36a083b74.camel@lasnet.de/
Reviewed-by: David Ahern &lt;dsahern@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>ipv6: add READ_ONCE(sk-&gt;sk_bound_dev_if) in INET6_MATCH()</title>
<updated>2022-08-17T12:23:36+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-05-13T18:55:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8fd69d3df9f434ae417b5f352c3d666544d10546'/>
<id>8fd69d3df9f434ae417b5f352c3d666544d10546</id>
<content type='text'>
[ Upstream commit 5d368f03280d3678433a7f119efe15dfbbb87bc8 ]

INET6_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET6_MATCH() an inline function
to ease our changes.

v2: inline function only defined if IS_ENABLED(CONFIG_IPV6)
    Change the name to inet6_match(), this is no longer a macro.

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 5d368f03280d3678433a7f119efe15dfbbb87bc8 ]

INET6_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET6_MATCH() an inline function
to ease our changes.

v2: inline function only defined if IS_ENABLED(CONFIG_IPV6)
    Change the name to inet6_match(), this is no longer a macro.

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>inet: add READ_ONCE(sk-&gt;sk_bound_dev_if) in INET_MATCH()</title>
<updated>2022-08-17T12:23:35+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-05-12T16:56:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=68bf74ec95c3046f51893a9c80e2d4ac526600de'/>
<id>68bf74ec95c3046f51893a9c80e2d4ac526600de</id>
<content type='text'>
[ Upstream commit 4915d50e300e96929d2462041d6f6c6f061167fd ]

INET_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET_MATCH() an inline function
to ease our changes.

v2:

We remove the 32bit version of it, as modern compilers
should generate the same code really, no need to
try to be smarter.

Also make 'struct net *net' the first argument.

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 4915d50e300e96929d2462041d6f6c6f061167fd ]

INET_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET_MATCH() an inline function
to ease our changes.

v2:

We remove the 32bit version of it, as modern compilers
should generate the same code really, no need to
try to be smarter.

Also make 'struct net *net' the first argument.

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: fix sk_wmem_schedule() and sk_rmem_schedule() errors</title>
<updated>2022-08-17T12:23:19+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-06-09T06:34:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ab5a4e0cbfe3d506315ab6260ac7c76e49934927'/>
<id>ab5a4e0cbfe3d506315ab6260ac7c76e49934927</id>
<content type='text'>
[ Upstream commit 7c80b038d23e1f4c7fcc311f43f83b8c60e7fb80 ]

If sk-&gt;sk_forward_alloc is 150000, and we need to schedule 150001 bytes,
we want to allocate 1 byte more (rounded up to one page),
instead of 150001 :/

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&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 7c80b038d23e1f4c7fcc311f43f83b8c60e7fb80 ]

If sk-&gt;sk_forward_alloc is 150000, and we need to schedule 150001 bytes,
we want to allocate 1 byte more (rounded up to one page),
instead of 150001 :/

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Fix data-races around sysctl_[rw]mem(_offset)?.</title>
<updated>2022-08-03T10:03:51+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-22T18:22:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=618116a273b7a4df296296bd1b4057e41b77e9f1'/>
<id>618116a273b7a4df296296bd1b4057e41b77e9f1</id>
<content type='text'>
[ Upstream commit 02739545951ad4c1215160db7fbf9b7a918d3c0b ]

While reading these sysctl variables, they can be changed concurrently.
Thus, we need to add READ_ONCE() to their readers.

  - .sysctl_rmem
  - .sysctl_rwmem
  - .sysctl_rmem_offset
  - .sysctl_wmem_offset
  - sysctl_tcp_rmem[1, 2]
  - sysctl_tcp_wmem[1, 2]
  - sysctl_decnet_rmem[1]
  - sysctl_decnet_wmem[1]
  - sysctl_tipc_rmem[1]

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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 02739545951ad4c1215160db7fbf9b7a918d3c0b ]

While reading these sysctl variables, they can be changed concurrently.
Thus, we need to add READ_ONCE() to their readers.

  - .sysctl_rmem
  - .sysctl_rwmem
  - .sysctl_rmem_offset
  - .sysctl_wmem_offset
  - sysctl_tcp_rmem[1, 2]
  - sysctl_tcp_wmem[1, 2]
  - sysctl_decnet_rmem[1]
  - sysctl_decnet_wmem[1]
  - sysctl_tipc_rmem[1]

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.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>ipv6/addrconf: fix a null-ptr-deref bug for ip6_ptr</title>
<updated>2022-08-03T10:03:47+00:00</updated>
<author>
<name>Ziyang Xuan</name>
<email>william.xuanziyang@huawei.com</email>
</author>
<published>2022-07-28T01:33:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=189e370b8250d9c07091f9cf58b6618945c1ec71'/>
<id>189e370b8250d9c07091f9cf58b6618945c1ec71</id>
<content type='text'>
commit 85f0173df35e5462d89947135a6a5599c6c3ef6f upstream.

Change net device's MTU to smaller than IPV6_MIN_MTU or unregister
device while matching route. That may trigger null-ptr-deref bug
for ip6_ptr probability as following.

=========================================================
BUG: KASAN: null-ptr-deref in find_match.part.0+0x70/0x134
Read of size 4 at addr 0000000000000308 by task ping6/263

CPU: 2 PID: 263 Comm: ping6 Not tainted 5.19.0-rc7+ #14
Call trace:
 dump_backtrace+0x1a8/0x230
 show_stack+0x20/0x70
 dump_stack_lvl+0x68/0x84
 print_report+0xc4/0x120
 kasan_report+0x84/0x120
 __asan_load4+0x94/0xd0
 find_match.part.0+0x70/0x134
 __find_rr_leaf+0x408/0x470
 fib6_table_lookup+0x264/0x540
 ip6_pol_route+0xf4/0x260
 ip6_pol_route_output+0x58/0x70
 fib6_rule_lookup+0x1a8/0x330
 ip6_route_output_flags_noref+0xd8/0x1a0
 ip6_route_output_flags+0x58/0x160
 ip6_dst_lookup_tail+0x5b4/0x85c
 ip6_dst_lookup_flow+0x98/0x120
 rawv6_sendmsg+0x49c/0xc70
 inet_sendmsg+0x68/0x94

Reproducer as following:
Firstly, prepare conditions:
$ip netns add ns1
$ip netns add ns2
$ip link add veth1 type veth peer name veth2
$ip link set veth1 netns ns1
$ip link set veth2 netns ns2
$ip netns exec ns1 ip -6 addr add 2001:0db8:0:f101::1/64 dev veth1
$ip netns exec ns2 ip -6 addr add 2001:0db8:0:f101::2/64 dev veth2
$ip netns exec ns1 ifconfig veth1 up
$ip netns exec ns2 ifconfig veth2 up
$ip netns exec ns1 ip -6 route add 2000::/64 dev veth1 metric 1
$ip netns exec ns2 ip -6 route add 2001::/64 dev veth2 metric 1

Secondly, execute the following two commands in two ssh windows
respectively:
$ip netns exec ns1 sh
$while true; do ip -6 addr add 2001:0db8:0:f101::1/64 dev veth1; ip -6 route add 2000::/64 dev veth1 metric 1; ping6 2000::2; done

$ip netns exec ns1 sh
$while true; do ip link set veth1 mtu 1000; ip link set veth1 mtu 1500; sleep 5; done

It is because ip6_ptr has been assigned to NULL in addrconf_ifdown() firstly,
then ip6_ignore_linkdown() accesses ip6_ptr directly without NULL check.

	cpu0			cpu1
fib6_table_lookup
__find_rr_leaf
			addrconf_notify [ NETDEV_CHANGEMTU ]
			addrconf_ifdown
			RCU_INIT_POINTER(dev-&gt;ip6_ptr, NULL)
find_match
ip6_ignore_linkdown

So we can add NULL check for ip6_ptr before using in ip6_ignore_linkdown() to
fix the null-ptr-deref bug.

Fixes: dcd1f572954f ("net/ipv6: Remove fib6_idev")
Signed-off-by: Ziyang Xuan &lt;william.xuanziyang@huawei.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20220728013307.656257-1-william.xuanziyang@huawei.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.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 85f0173df35e5462d89947135a6a5599c6c3ef6f upstream.

Change net device's MTU to smaller than IPV6_MIN_MTU or unregister
device while matching route. That may trigger null-ptr-deref bug
for ip6_ptr probability as following.

=========================================================
BUG: KASAN: null-ptr-deref in find_match.part.0+0x70/0x134
Read of size 4 at addr 0000000000000308 by task ping6/263

CPU: 2 PID: 263 Comm: ping6 Not tainted 5.19.0-rc7+ #14
Call trace:
 dump_backtrace+0x1a8/0x230
 show_stack+0x20/0x70
 dump_stack_lvl+0x68/0x84
 print_report+0xc4/0x120
 kasan_report+0x84/0x120
 __asan_load4+0x94/0xd0
 find_match.part.0+0x70/0x134
 __find_rr_leaf+0x408/0x470
 fib6_table_lookup+0x264/0x540
 ip6_pol_route+0xf4/0x260
 ip6_pol_route_output+0x58/0x70
 fib6_rule_lookup+0x1a8/0x330
 ip6_route_output_flags_noref+0xd8/0x1a0
 ip6_route_output_flags+0x58/0x160
 ip6_dst_lookup_tail+0x5b4/0x85c
 ip6_dst_lookup_flow+0x98/0x120
 rawv6_sendmsg+0x49c/0xc70
 inet_sendmsg+0x68/0x94

Reproducer as following:
Firstly, prepare conditions:
$ip netns add ns1
$ip netns add ns2
$ip link add veth1 type veth peer name veth2
$ip link set veth1 netns ns1
$ip link set veth2 netns ns2
$ip netns exec ns1 ip -6 addr add 2001:0db8:0:f101::1/64 dev veth1
$ip netns exec ns2 ip -6 addr add 2001:0db8:0:f101::2/64 dev veth2
$ip netns exec ns1 ifconfig veth1 up
$ip netns exec ns2 ifconfig veth2 up
$ip netns exec ns1 ip -6 route add 2000::/64 dev veth1 metric 1
$ip netns exec ns2 ip -6 route add 2001::/64 dev veth2 metric 1

Secondly, execute the following two commands in two ssh windows
respectively:
$ip netns exec ns1 sh
$while true; do ip -6 addr add 2001:0db8:0:f101::1/64 dev veth1; ip -6 route add 2000::/64 dev veth1 metric 1; ping6 2000::2; done

$ip netns exec ns1 sh
$while true; do ip link set veth1 mtu 1000; ip link set veth1 mtu 1500; sleep 5; done

It is because ip6_ptr has been assigned to NULL in addrconf_ifdown() firstly,
then ip6_ignore_linkdown() accesses ip6_ptr directly without NULL check.

	cpu0			cpu1
fib6_table_lookup
__find_rr_leaf
			addrconf_notify [ NETDEV_CHANGEMTU ]
			addrconf_ifdown
			RCU_INIT_POINTER(dev-&gt;ip6_ptr, NULL)
find_match
ip6_ignore_linkdown

So we can add NULL check for ip6_ptr before using in ip6_ignore_linkdown() to
fix the null-ptr-deref bug.

Fixes: dcd1f572954f ("net/ipv6: Remove fib6_idev")
Signed-off-by: Ziyang Xuan &lt;william.xuanziyang@huawei.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20220728013307.656257-1-william.xuanziyang@huawei.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "tcp: change pingpong threshold to 3"</title>
<updated>2022-08-03T10:03:45+00:00</updated>
<author>
<name>Wei Wang</name>
<email>weiwan@google.com</email>
</author>
<published>2022-07-21T20:44:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=927c5cf0ba3e15d601bcc5cc0ee71f2422754b61'/>
<id>927c5cf0ba3e15d601bcc5cc0ee71f2422754b61</id>
<content type='text'>
commit 4d8f24eeedc58d5f87b650ddda73c16e8ba56559 upstream.

This reverts commit 4a41f453bedfd5e9cd040bad509d9da49feb3e2c.

This to-be-reverted commit was meant to apply a stricter rule for the
stack to enter pingpong mode. However, the condition used to check for
interactive session "before(tp-&gt;lsndtime, icsk-&gt;icsk_ack.lrcvtime)" is
jiffy based and might be too coarse, which delays the stack entering
pingpong mode.
We revert this patch so that we no longer use the above condition to
determine interactive session, and also reduce pingpong threshold to 1.

Fixes: 4a41f453bedf ("tcp: change pingpong threshold to 3")
Reported-by: LemmyHuang &lt;hlm3280@163.com&gt;
Suggested-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Wei Wang &lt;weiwan@google.com&gt;
Acked-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20220721204404.388396-1-weiwan@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.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 4d8f24eeedc58d5f87b650ddda73c16e8ba56559 upstream.

This reverts commit 4a41f453bedfd5e9cd040bad509d9da49feb3e2c.

This to-be-reverted commit was meant to apply a stricter rule for the
stack to enter pingpong mode. However, the condition used to check for
interactive session "before(tp-&gt;lsndtime, icsk-&gt;icsk_ack.lrcvtime)" is
jiffy based and might be too coarse, which delays the stack entering
pingpong mode.
We revert this patch so that we no longer use the above condition to
determine interactive session, and also reduce pingpong threshold to 1.

Fixes: 4a41f453bedf ("tcp: change pingpong threshold to 3")
Reported-by: LemmyHuang &lt;hlm3280@163.com&gt;
Suggested-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Wei Wang &lt;weiwan@google.com&gt;
Acked-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20220721204404.388396-1-weiwan@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
