<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/ipv6, branch v5.4.16</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>xfrm: support output_mark for offload ESP packets</title>
<updated>2020-01-29T15:45:31+00:00</updated>
<author>
<name>Ulrich Weber</name>
<email>ulrich.weber@gmail.com</email>
</author>
<published>2020-01-15T11:11:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b2e061912c3ec2843e149208fc0160c2bed877cb'/>
<id>b2e061912c3ec2843e149208fc0160c2bed877cb</id>
<content type='text'>
commit 4e4362d2bf2a49ff44dbbc9585207977ca3d71d0 upstream.

Commit 9b42c1f179a6 ("xfrm: Extend the output_mark") added output_mark
support but missed ESP offload support.

xfrm_smark_get() is not called within xfrm_input() for packets coming
from esp4_gro_receive() or esp6_gro_receive(). Therefore call
xfrm_smark_get() directly within these functions.

Fixes: 9b42c1f179a6 ("xfrm: Extend the output_mark to support input direction and masking.")
Signed-off-by: Ulrich Weber &lt;ulrich.weber@gmail.com&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.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 4e4362d2bf2a49ff44dbbc9585207977ca3d71d0 upstream.

Commit 9b42c1f179a6 ("xfrm: Extend the output_mark") added output_mark
support but missed ESP offload support.

xfrm_smark_get() is not called within xfrm_input() for packets coming
from esp4_gro_receive() or esp6_gro_receive(). Therefore call
xfrm_smark_get() directly within these functions.

Fixes: 9b42c1f179a6 ("xfrm: Extend the output_mark to support input direction and masking.")
Signed-off-by: Ulrich Weber &lt;ulrich.weber@gmail.com&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>net, ip6_tunnel: fix namespaces move</title>
<updated>2020-01-29T15:45:20+00:00</updated>
<author>
<name>William Dauchy</name>
<email>w.dauchy@criteo.com</email>
</author>
<published>2020-01-21T20:49:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ead0377f601ec3aae7965fb16da28685963a097b'/>
<id>ead0377f601ec3aae7965fb16da28685963a097b</id>
<content type='text'>
[ Upstream commit 5311a69aaca30fa849c3cc46fb25f75727fb72d0 ]

in the same manner as commit d0f418516022 ("net, ip_tunnel: fix
namespaces move"), fix namespace moving as it was broken since commit
8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnel"), but for
ipv6 this time; there is no reason to keep it for ip6_tunnel.

Fixes: 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnel")
Signed-off-by: William Dauchy &lt;w.dauchy@criteo.com&gt;
Acked-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 5311a69aaca30fa849c3cc46fb25f75727fb72d0 ]

in the same manner as commit d0f418516022 ("net, ip_tunnel: fix
namespaces move"), fix namespace moving as it was broken since commit
8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnel"), but for
ipv6 this time; there is no reason to keep it for ip6_tunnel.

Fixes: 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnel")
Signed-off-by: William Dauchy &lt;w.dauchy@criteo.com&gt;
Acked-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: ip6_gre: fix moving ip6gre between namespaces</title>
<updated>2020-01-29T15:45:20+00:00</updated>
<author>
<name>Niko Kortstrom</name>
<email>niko.kortstrom@nokia.com</email>
</author>
<published>2020-01-16T09:43:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7943bb0f06365cf5e32f3cf8a6b29eeae981fb8a'/>
<id>7943bb0f06365cf5e32f3cf8a6b29eeae981fb8a</id>
<content type='text'>
[ Upstream commit 690afc165bb314354667f67157c1a1aea7dc797a ]

Support for moving IPv4 GRE tunnels between namespaces was added in
commit b57708add314 ("gre: add x-netns support"). The respective change
for IPv6 tunnels, commit 22f08069e8b4 ("ip6gre: add x-netns support")
did not drop NETIF_F_NETNS_LOCAL flag so moving them from one netns to
another is still denied in IPv6 case. Drop NETIF_F_NETNS_LOCAL flag from
ip6gre tunnels to allow moving ip6gre tunnel endpoints between network
namespaces.

Signed-off-by: Niko Kortstrom &lt;niko.kortstrom@nokia.com&gt;
Acked-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Acked-by: William Tu &lt;u9012063@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 690afc165bb314354667f67157c1a1aea7dc797a ]

Support for moving IPv4 GRE tunnels between namespaces was added in
commit b57708add314 ("gre: add x-netns support"). The respective change
for IPv6 tunnels, commit 22f08069e8b4 ("ip6gre: add x-netns support")
did not drop NETIF_F_NETNS_LOCAL flag so moving them from one netns to
another is still denied in IPv6 case. Drop NETIF_F_NETNS_LOCAL flag from
ip6gre tunnels to allow moving ip6gre tunnel endpoints between network
namespaces.

Signed-off-by: Niko Kortstrom &lt;niko.kortstrom@nokia.com&gt;
Acked-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Acked-by: William Tu &lt;u9012063@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: sr: remove SKB_GSO_IPXIP6 on End.D* actions</title>
<updated>2020-01-29T15:45:20+00:00</updated>
<author>
<name>Yuki Taguchi</name>
<email>tagyounit@gmail.com</email>
</author>
<published>2020-01-20T04:48:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e2bd33937c507df324176da01a99448bf3864b4c'/>
<id>e2bd33937c507df324176da01a99448bf3864b4c</id>
<content type='text'>
[ Upstream commit 62ebaeaedee7591c257543d040677a60e35c7aec ]

After LRO/GRO is applied, SRv6 encapsulated packets have
SKB_GSO_IPXIP6 feature flag, and this flag must be removed right after
decapulation procedure.

Currently, SKB_GSO_IPXIP6 flag is not removed on End.D* actions, which
creates inconsistent packet state, that is, a normal TCP/IP packets
have the SKB_GSO_IPXIP6 flag. This behavior can cause unexpected
fallback to GSO on routing to netdevices that do not support
SKB_GSO_IPXIP6. For example, on inter-VRF forwarding, decapsulated
packets separated into small packets by GSO because VRF devices do not
support TSO for packets with SKB_GSO_IPXIP6 flag, and this degrades
forwarding performance.

This patch removes encapsulation related GSO flags from the skb right
after the End.D* action is applied.

Fixes: d7a669dd2f8b ("ipv6: sr: add helper functions for seg6local")
Signed-off-by: Yuki Taguchi &lt;tagyounit@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 62ebaeaedee7591c257543d040677a60e35c7aec ]

After LRO/GRO is applied, SRv6 encapsulated packets have
SKB_GSO_IPXIP6 feature flag, and this flag must be removed right after
decapulation procedure.

Currently, SKB_GSO_IPXIP6 flag is not removed on End.D* actions, which
creates inconsistent packet state, that is, a normal TCP/IP packets
have the SKB_GSO_IPXIP6 flag. This behavior can cause unexpected
fallback to GSO on routing to netdevices that do not support
SKB_GSO_IPXIP6. For example, on inter-VRF forwarding, decapsulated
packets separated into small packets by GSO because VRF devices do not
support TSO for packets with SKB_GSO_IPXIP6 flag, and this degrades
forwarding performance.

This patch removes encapsulation related GSO flags from the skb right
after the End.D* action is applied.

Fixes: d7a669dd2f8b ("ipv6: sr: add helper functions for seg6local")
Signed-off-by: Yuki Taguchi &lt;tagyounit@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6/addrconf: only check invalid header values when NETLINK_F_STRICT_CHK is set</title>
<updated>2020-01-04T18:19:17+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-12-11T14:20:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8fa4ec03512d603efdd22d7a9bc45a22a99d122f'/>
<id>8fa4ec03512d603efdd22d7a9bc45a22a99d122f</id>
<content type='text'>
[ Upstream commit 2beb6d2901a3f73106485d560c49981144aeacb1 ]

In commit 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for
doit handlers") we add strict check for inet6_rtm_getaddr(). But we did
the invalid header values check before checking if NETLINK_F_STRICT_CHK
is set. This may break backwards compatibility if user already set the
ifm-&gt;ifa_prefixlen, ifm-&gt;ifa_flags, ifm-&gt;ifa_scope in their netlink code.

I didn't move the nlmsg_len check because I thought it's a valid check.

Reported-by: Jianlin Shi &lt;jishi@redhat.com&gt;
Fixes: 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for doit handlers")
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Reviewed-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2beb6d2901a3f73106485d560c49981144aeacb1 ]

In commit 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for
doit handlers") we add strict check for inet6_rtm_getaddr(). But we did
the invalid header values check before checking if NETLINK_F_STRICT_CHK
is set. This may break backwards compatibility if user already set the
ifm-&gt;ifa_prefixlen, ifm-&gt;ifa_flags, ifm-&gt;ifa_scope in their netlink code.

I didn't move the nlmsg_len check because I thought it's a valid check.

Reported-by: Jianlin Shi &lt;jishi@redhat.com&gt;
Fixes: 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for doit handlers")
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Reviewed-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sit: do not confirm neighbor when do pmtu update</title>
<updated>2020-01-04T18:19:04+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-12-22T02:51:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=57a5af98a28531402172d63137cda2e62073026a'/>
<id>57a5af98a28531402172d63137cda2e62073026a</id>
<content type='text'>
[ Upstream commit 4d42df46d6372ece4cb4279870b46c2ea7304a47 ]

When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4d42df46d6372ece4cb4279870b46c2ea7304a47 ]

When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vti: do not confirm neighbor when do pmtu update</title>
<updated>2020-01-04T18:19:03+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-12-22T02:51:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bcf4fe619c778bf055ef0e2c91ee65cc7b028e5f'/>
<id>bcf4fe619c778bf055ef0e2c91ee65cc7b028e5f</id>
<content type='text'>
[ Upstream commit 8247a79efa2f28b44329f363272550c1738377de ]

When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

Although vti and vti6 are immune to this problem because they are IFF_NOARP
interfaces, as Guillaume pointed. There is still no sense to confirm neighbour
here.

v5: Update commit description.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8247a79efa2f28b44329f363272550c1738377de ]

When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

Although vti and vti6 are immune to this problem because they are IFF_NOARP
interfaces, as Guillaume pointed. There is still no sense to confirm neighbour
here.

v5: Update commit description.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tunnel: do not confirm neighbor when do pmtu update</title>
<updated>2020-01-04T18:19:02+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-12-22T02:51:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=020546ec66665c4c80edb847bbcd5b4937bdddff'/>
<id>020546ec66665c4c80edb847bbcd5b4937bdddff</id>
<content type='text'>
[ Upstream commit 7a1592bcb15d71400a98632727791d1e68ea0ee8 ]

When do tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

v5: No Change.
v4: Update commit description
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Fixes: 0dec879f636f ("net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP")
Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Tested-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7a1592bcb15d71400a98632727791d1e68ea0ee8 ]

When do tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

v5: No Change.
v4: Update commit description
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Fixes: 0dec879f636f ("net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP")
Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Tested-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ip6_gre: do not confirm neighbor when do pmtu update</title>
<updated>2020-01-04T18:18:59+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-12-22T02:51:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=871d063728649733c3d6fac2fe210f07b186f0a7'/>
<id>871d063728649733c3d6fac2fe210f07b186f0a7</id>
<content type='text'>
[ Upstream commit 675d76ad0ad5bf41c9a129772ef0aba8f57ea9a7 ]

When we do ipv6 gre pmtu update, we will also do neigh confirm currently.
This will cause the neigh cache be refreshed and set to REACHABLE before
xmit.

But if the remote mac address changed, e.g. device is deleted and recreated,
we will not able to notice this and still use the old mac address as the neigh
cache is REACHABLE.

Fix this by disable neigh confirm when do pmtu update

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reported-by: Jianlin Shi &lt;jishi@redhat.com&gt;
Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 675d76ad0ad5bf41c9a129772ef0aba8f57ea9a7 ]

When we do ipv6 gre pmtu update, we will also do neigh confirm currently.
This will cause the neigh cache be refreshed and set to REACHABLE before
xmit.

But if the remote mac address changed, e.g. device is deleted and recreated,
we will not able to notice this and still use the old mac address as the neigh
cache is REACHABLE.

Fix this by disable neigh confirm when do pmtu update

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reported-by: Jianlin Shi &lt;jishi@redhat.com&gt;
Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: add bool confirm_neigh parameter for dst_ops.update_pmtu</title>
<updated>2020-01-04T18:18:58+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-12-22T02:51:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d49ce85cad06d00455f80030333131cb93cf1619'/>
<id>d49ce85cad06d00455f80030333131cb93cf1619</id>
<content type='text'>
[ Upstream commit bd085ef678b2cc8c38c105673dfe8ff8f5ec0c57 ]

The MTU update code is supposed to be invoked in response to real
networking events that update the PMTU. In IPv6 PMTU update function
__ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor
confirmed time.

But for tunnel code, it will call pmtu before xmit, like:
  - tnl_update_pmtu()
    - skb_dst_update_pmtu()
      - ip6_rt_update_pmtu()
        - __ip6_rt_update_pmtu()
          - dst_confirm_neigh()

If the tunnel remote dst mac address changed and we still do the neigh
confirm, we will not be able to update neigh cache and ping6 remote
will failed.

So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we
should not be invoking dst_confirm_neigh() as we have no evidence
of successful two-way communication at this point.

On the other hand it is also important to keep the neigh reachability fresh
for TCP flows, so we cannot remove this dst_confirm_neigh() call.

To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu
to choose whether we should do neigh update or not. I will add the parameter
in this patch and set all the callers to true to comply with the previous
way, and fix the tunnel code one by one on later patches.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Suggested-by: David Miller &lt;davem@davemloft.net&gt;
Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit bd085ef678b2cc8c38c105673dfe8ff8f5ec0c57 ]

The MTU update code is supposed to be invoked in response to real
networking events that update the PMTU. In IPv6 PMTU update function
__ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor
confirmed time.

But for tunnel code, it will call pmtu before xmit, like:
  - tnl_update_pmtu()
    - skb_dst_update_pmtu()
      - ip6_rt_update_pmtu()
        - __ip6_rt_update_pmtu()
          - dst_confirm_neigh()

If the tunnel remote dst mac address changed and we still do the neigh
confirm, we will not be able to update neigh cache and ping6 remote
will failed.

So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we
should not be invoking dst_confirm_neigh() as we have no evidence
of successful two-way communication at this point.

On the other hand it is also important to keep the neigh reachability fresh
for TCP flows, so we cannot remove this dst_confirm_neigh() call.

To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu
to choose whether we should do neigh update or not. I will add the parameter
in this patch and set all the callers to true to comply with the previous
way, and fix the tunnel code one by one on later patches.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Suggested-by: David Miller &lt;davem@davemloft.net&gt;
Reviewed-by: Guillaume Nault &lt;gnault@redhat.com&gt;
Acked-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
