<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/net/veth.c, branch v6.7</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>net: veth: fix packet segmentation in veth_convert_skb_to_xdp_buff</title>
<updated>2023-12-06T03:24:26+00:00</updated>
<author>
<name>Lorenzo Bianconi</name>
<email>lorenzo@kernel.org</email>
</author>
<published>2023-12-04T15:01:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a61f46e1102545cf1fb5f19992288265362cefb0'/>
<id>a61f46e1102545cf1fb5f19992288265362cefb0</id>
<content type='text'>
Based on the previous allocated packet, page_offset can be not null
in veth_convert_skb_to_xdp_buff routine.
Take into account page fragment offset during the skb paged area copy
in veth_convert_skb_to_xdp_buff().

Fixes: 2d0de67da51a ("net: veth: use newly added page pool API for veth with xdp")
Signed-off-by: Lorenzo Bianconi &lt;lorenzo@kernel.org&gt;
Reviewed-by: Yunsheng Lin &lt;linyunsheng@huawei.com&gt;
Link: https://lore.kernel.org/r/eddfe549e7e626870071930964ac3c38a1dc8068.1701702000.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Based on the previous allocated packet, page_offset can be not null
in veth_convert_skb_to_xdp_buff routine.
Take into account page fragment offset during the skb paged area copy
in veth_convert_skb_to_xdp_buff().

Fixes: 2d0de67da51a ("net: veth: use newly added page pool API for veth with xdp")
Signed-off-by: Lorenzo Bianconi &lt;lorenzo@kernel.org&gt;
Reviewed-by: Yunsheng Lin &lt;linyunsheng@huawei.com&gt;
Link: https://lore.kernel.org/r/eddfe549e7e626870071930964ac3c38a1dc8068.1701702000.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: veth: fix ethtool stats reporting</title>
<updated>2023-11-23T12:23:59+00:00</updated>
<author>
<name>Lorenzo Bianconi</name>
<email>lorenzo@kernel.org</email>
</author>
<published>2023-11-21T19:08:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=818ad9cc90d4a7165caaee7e32800c50d0564ec3'/>
<id>818ad9cc90d4a7165caaee7e32800c50d0564ec3</id>
<content type='text'>
Fix a possible misalignment between page_pool stats and tx xdp_stats
reported in veth_get_ethtool_stats routine.
The issue can be reproduced configuring the veth pair with the
following tx/rx queues:

$ip link add v0 numtxqueues 2 numrxqueues 4 type veth peer name v1 \
 numtxqueues 1 numrxqueues 1

and loading a simple XDP program on v0 that just returns XDP_PASS.
In this case on v0 the page_pool stats overwrites tx xdp_stats for queue 1.
Fix the issue incrementing pp_idx of dev-&gt;real_num_tx_queues * VETH_TQ_STATS_LEN
since we always report xdp_stats for all tx queues in ethtool.

Fixes: 4fc418053ec7 ("net: veth: add page_pool stats")
Signed-off-by: Lorenzo Bianconi &lt;lorenzo@kernel.org&gt;
Link: https://lore.kernel.org/r/c5b5d0485016836448453f12846c7c4ab75b094a.1700593593.git.lorenzo@kernel.org
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix a possible misalignment between page_pool stats and tx xdp_stats
reported in veth_get_ethtool_stats routine.
The issue can be reproduced configuring the veth pair with the
following tx/rx queues:

$ip link add v0 numtxqueues 2 numrxqueues 4 type veth peer name v1 \
 numtxqueues 1 numrxqueues 1

and loading a simple XDP program on v0 that just returns XDP_PASS.
In this case on v0 the page_pool stats overwrites tx xdp_stats for queue 1.
Fix the issue incrementing pp_idx of dev-&gt;real_num_tx_queues * VETH_TQ_STATS_LEN
since we always report xdp_stats for all tx queues in ethtool.

Fixes: 4fc418053ec7 ("net: veth: add page_pool stats")
Signed-off-by: Lorenzo Bianconi &lt;lorenzo@kernel.org&gt;
Link: https://lore.kernel.org/r/c5b5d0485016836448453f12846c7c4ab75b094a.1700593593.git.lorenzo@kernel.org
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>veth: Use tstats per-CPU traffic counters</title>
<updated>2023-11-20T18:15:16+00:00</updated>
<author>
<name>Peilin Ye</name>
<email>peilin.ye@bytedance.com</email>
</author>
<published>2023-11-14T00:42:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6f2684bf2b4460c84d0d34612a939f78b96b03fc'/>
<id>6f2684bf2b4460c84d0d34612a939f78b96b03fc</id>
<content type='text'>
Currently veth devices use the lstats per-CPU traffic counters, which only
cover TX traffic. veth_get_stats64() actually populates RX stats of a veth
device from its peer's TX counters, based on the assumption that a veth
device can _only_ receive packets from its peer, which is no longer true:

For example, recent CNIs (like Cilium) can use the bpf_redirect_peer() BPF
helper to redirect traffic from NIC's tc ingress to veth's tc ingress (in
a different netns), skipping veth's peer device. Unfortunately, this kind
of traffic isn't currently accounted for in veth's RX stats.

In preparation for the fix, use tstats (instead of lstats) to maintain
both RX and TX counters for each veth device. We'll use RX counters for
bpf_redirect_peer() traffic, and keep using TX counters for the usual
"peer-to-peer" traffic. In veth_get_stats64(), calculate RX stats by
_adding_ RX count to peer's TX count, in order to cover both kinds of
traffic.

veth_stats_rx() might need a name change (perhaps to "veth_stats_xdp()")
for less confusion, but let's leave it to another patch to keep the fix
minimal.

Signed-off-by: Peilin Ye &lt;peilin.ye@bytedance.com&gt;
Co-developed-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Link: https://lore.kernel.org/r/20231114004220.6495-5-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently veth devices use the lstats per-CPU traffic counters, which only
cover TX traffic. veth_get_stats64() actually populates RX stats of a veth
device from its peer's TX counters, based on the assumption that a veth
device can _only_ receive packets from its peer, which is no longer true:

For example, recent CNIs (like Cilium) can use the bpf_redirect_peer() BPF
helper to redirect traffic from NIC's tc ingress to veth's tc ingress (in
a different netns), skipping veth's peer device. Unfortunately, this kind
of traffic isn't currently accounted for in veth's RX stats.

In preparation for the fix, use tstats (instead of lstats) to maintain
both RX and TX counters for each veth device. We'll use RX counters for
bpf_redirect_peer() traffic, and keep using TX counters for the usual
"peer-to-peer" traffic. In veth_get_stats64(), calculate RX stats by
_adding_ RX count to peer's TX count, in order to cover both kinds of
traffic.

veth_stats_rx() might need a name change (perhaps to "veth_stats_xdp()")
for less confusion, but let's leave it to another patch to keep the fix
minimal.

Signed-off-by: Peilin Ye &lt;peilin.ye@bytedance.com&gt;
Co-developed-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Link: https://lore.kernel.org/r/20231114004220.6495-5-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: Move {l,t,d}stats allocation to core and convert veth &amp; vrf</title>
<updated>2023-11-20T18:15:16+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2023-11-14T00:42:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=34d21de99cea9cb17967874313e5b0262527833c'/>
<id>34d21de99cea9cb17967874313e5b0262527833c</id>
<content type='text'>
Move {l,t,d}stats allocation to the core and let netdevs pick the stats
type they need. That way the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc) - all happening in the core.

Co-developed-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Cc: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20231114004220.6495-3-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move {l,t,d}stats allocation to the core and let netdevs pick the stats
type they need. That way the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc) - all happening in the core.

Co-developed-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Cc: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20231114004220.6495-3-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: veth: use newly added page pool API for veth with xdp</title>
<updated>2023-10-24T02:14:49+00:00</updated>
<author>
<name>Yunsheng Lin</name>
<email>linyunsheng@huawei.com</email>
</author>
<published>2023-10-20T09:59:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2d0de67da51a90c6acf7bf08d7b0501f45408002'/>
<id>2d0de67da51a90c6acf7bf08d7b0501f45408002</id>
<content type='text'>
Use page_pool_alloc() API to allocate memory with least
memory utilization and performance penalty.

Signed-off-by: Yunsheng Lin &lt;linyunsheng@huawei.com&gt;
CC: Lorenzo Bianconi &lt;lorenzo@kernel.org&gt;
CC: Alexander Duyck &lt;alexander.duyck@gmail.com&gt;
CC: Liang Chen &lt;liangchen.linux@gmail.com&gt;
CC: Alexander Lobakin &lt;aleksander.lobakin@intel.com&gt;
Link: https://lore.kernel.org/r/20231020095952.11055-6-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use page_pool_alloc() API to allocate memory with least
memory utilization and performance penalty.

Signed-off-by: Yunsheng Lin &lt;linyunsheng@huawei.com&gt;
CC: Lorenzo Bianconi &lt;lorenzo@kernel.org&gt;
CC: Alexander Duyck &lt;alexander.duyck@gmail.com&gt;
CC: Liang Chen &lt;liangchen.linux@gmail.com&gt;
CC: Alexander Lobakin &lt;aleksander.lobakin@intel.com&gt;
Link: https://lore.kernel.org/r/20231020095952.11055-6-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>veth: Update XDP feature set when bringing up device</title>
<updated>2023-09-12T14:32:56+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@redhat.com</email>
</author>
<published>2023-09-11T13:58:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7a6102aa6df0d5d032b4cbc51935d1d4cda17254'/>
<id>7a6102aa6df0d5d032b4cbc51935d1d4cda17254</id>
<content type='text'>
There's an early return in veth_set_features() if the device is in a down
state, which leads to the XDP feature flags not being updated when enabling
GRO while the device is down. Which in turn leads to XDP_REDIRECT not
working, because the redirect code now checks the flags.

Fix this by updating the feature flags after bringing the device up.

Before this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	no
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	no

After this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	yes
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	yes

Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Link: https://lore.kernel.org/r/20230911135826.722295-1-toke@redhat.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There's an early return in veth_set_features() if the device is in a down
state, which leads to the XDP feature flags not being updated when enabling
GRO while the device is down. Which in turn leads to XDP_REDIRECT not
working, because the redirect code now checks the flags.

Fix this by updating the feature flags after bringing the device up.

Before this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	no
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	no

After this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	yes
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	yes

Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features")
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Link: https://lore.kernel.org/r/20230911135826.722295-1-toke@redhat.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>veth: Fixing transmit return status for dropped packets</title>
<updated>2023-09-04T05:52:39+00:00</updated>
<author>
<name>Liang Chen</name>
<email>liangchen.linux@gmail.com</email>
</author>
<published>2023-09-01T04:09:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=151e887d8ff97e2e42110ffa1fb1e6a2128fb364'/>
<id>151e887d8ff97e2e42110ffa1fb1e6a2128fb364</id>
<content type='text'>
The veth_xmit function returns NETDEV_TX_OK even when packets are dropped.
This behavior leads to incorrect calculations of statistics counts, as
well as things like txq-&gt;trans_start updates.

Fixes: e314dbdc1c0d ("[NET]: Virtual ethernet device driver.")
Signed-off-by: Liang Chen &lt;liangchen.linux@gmail.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The veth_xmit function returns NETDEV_TX_OK even when packets are dropped.
This behavior leads to incorrect calculations of statistics counts, as
well as things like txq-&gt;trans_start updates.

Fixes: e314dbdc1c0d ("[NET]: Virtual ethernet device driver.")
Signed-off-by: Liang Chen &lt;liangchen.linux@gmail.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>veth: Avoid NAPI scheduling on failed SKB forwarding</title>
<updated>2023-08-26T01:52:11+00:00</updated>
<author>
<name>Liang Chen</name>
<email>liangchen.linux@gmail.com</email>
</author>
<published>2023-08-24T12:31:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=215eb9f962091ebaab96be2c18cf5d0f5174a4d6'/>
<id>215eb9f962091ebaab96be2c18cf5d0f5174a4d6</id>
<content type='text'>
When an skb fails to be forwarded to the peer(e.g., skb data buffer
length exceeds MTU), it will not be added to the peer's receive queue.
Therefore, we should schedule the peer's NAPI poll function only when
skb forwarding is successful to avoid unnecessary overhead.

Signed-off-by: Liang Chen &lt;liangchen.linux@gmail.com&gt;
Link: https://lore.kernel.org/r/20230824123131.7673-1-liangchen.linux@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When an skb fails to be forwarded to the peer(e.g., skb data buffer
length exceeds MTU), it will not be added to the peer's receive queue.
Therefore, we should schedule the peer's NAPI poll function only when
skb forwarding is successful to avoid unnecessary overhead.

Signed-off-by: Liang Chen &lt;liangchen.linux@gmail.com&gt;
Link: https://lore.kernel.org/r/20230824123131.7673-1-liangchen.linux@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2023-08-24T17:51:39+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2023-08-24T17:46:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=57ce6427e00a6a72f74b29630b39548b36980b09'/>
<id>57ce6427e00a6a72f74b29630b39548b36980b09</id>
<content type='text'>
Cross-merge networking fixes after downstream PR.

Conflicts:

include/net/inet_sock.h
  f866fbc842de ("ipv4: fix data-races around inet-&gt;inet_id")
  c274af224269 ("inet: introduce inet-&gt;inet_flags")
https://lore.kernel.org/all/679ddff6-db6e-4ff6-b177-574e90d0103d@tessares.net/

Adjacent changes:

drivers/net/bonding/bond_alb.c
  e74216b8def3 ("bonding: fix macvlan over alb bond support")
  f11e5bd159b0 ("bonding: support balance-alb with openvswitch")

drivers/net/ethernet/broadcom/bgmac.c
  d6499f0b7c7c ("net: bgmac: Return PTR_ERR() for fixed_phy_register()")
  23a14488ea58 ("net: bgmac: Fix return value check for fixed_phy_register()")

drivers/net/ethernet/broadcom/genet/bcmmii.c
  32bbe64a1386 ("net: bcmgenet: Fix return value check for fixed_phy_register()")
  acf50d1adbf4 ("net: bcmgenet: Return PTR_ERR() for fixed_phy_register()")

net/sctp/socket.c
  f866fbc842de ("ipv4: fix data-races around inet-&gt;inet_id")
  b09bde5c3554 ("inet: move inet-&gt;mc_loop to inet-&gt;inet_frags")

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Cross-merge networking fixes after downstream PR.

Conflicts:

include/net/inet_sock.h
  f866fbc842de ("ipv4: fix data-races around inet-&gt;inet_id")
  c274af224269 ("inet: introduce inet-&gt;inet_flags")
https://lore.kernel.org/all/679ddff6-db6e-4ff6-b177-574e90d0103d@tessares.net/

Adjacent changes:

drivers/net/bonding/bond_alb.c
  e74216b8def3 ("bonding: fix macvlan over alb bond support")
  f11e5bd159b0 ("bonding: support balance-alb with openvswitch")

drivers/net/ethernet/broadcom/bgmac.c
  d6499f0b7c7c ("net: bgmac: Return PTR_ERR() for fixed_phy_register()")
  23a14488ea58 ("net: bgmac: Fix return value check for fixed_phy_register()")

drivers/net/ethernet/broadcom/genet/bcmmii.c
  32bbe64a1386 ("net: bcmgenet: Fix return value check for fixed_phy_register()")
  acf50d1adbf4 ("net: bcmgenet: Return PTR_ERR() for fixed_phy_register()")

net/sctp/socket.c
  f866fbc842de ("ipv4: fix data-races around inet-&gt;inet_id")
  b09bde5c3554 ("inet: move inet-&gt;mc_loop to inet-&gt;inet_frags")

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: validate veth and vxcan peer ifindexes</title>
<updated>2023-08-20T10:40:03+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2023-08-19T01:26:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f534f6581ec084fe94d6759f7672bd009794b07e'/>
<id>f534f6581ec084fe94d6759f7672bd009794b07e</id>
<content type='text'>
veth and vxcan need to make sure the ifindexes of the peer
are not negative, core does not validate this.

Using iproute2 with user-space-level checking removed:

Before:

  # ./ip link add index 10 type veth peer index -1
  # ip link show
  1: lo: &lt;LOOPBACK,UP,LOWER_UP&gt; mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  2: enp1s0: &lt;BROADCAST,MULTICAST,UP,LOWER_UP&gt; mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether 52:54:00:74:b2:03 brd ff:ff:ff:ff:ff:ff
  10: veth1@veth0: &lt;BROADCAST,MULTICAST,M-DOWN&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 8a:90:ff:57:6d:5d brd ff:ff:ff:ff:ff:ff
  -1: veth0@veth1: &lt;BROADCAST,MULTICAST,M-DOWN&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ae:ed:18:e6:fa:7f brd ff:ff:ff:ff:ff:ff

Now:

  $ ./ip link add index 10 type veth peer index -1
  Error: ifindex can't be negative.

This problem surfaced in net-next because an explicit WARN()
was added, the root cause is older.

Fixes: e6f8f1a739b6 ("veth: Allow to create peer link with given ifindex")
Fixes: a8f820a380a2 ("can: add Virtual CAN Tunnel driver (vxcan)")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
veth and vxcan need to make sure the ifindexes of the peer
are not negative, core does not validate this.

Using iproute2 with user-space-level checking removed:

Before:

  # ./ip link add index 10 type veth peer index -1
  # ip link show
  1: lo: &lt;LOOPBACK,UP,LOWER_UP&gt; mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  2: enp1s0: &lt;BROADCAST,MULTICAST,UP,LOWER_UP&gt; mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether 52:54:00:74:b2:03 brd ff:ff:ff:ff:ff:ff
  10: veth1@veth0: &lt;BROADCAST,MULTICAST,M-DOWN&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 8a:90:ff:57:6d:5d brd ff:ff:ff:ff:ff:ff
  -1: veth0@veth1: &lt;BROADCAST,MULTICAST,M-DOWN&gt; mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ae:ed:18:e6:fa:7f brd ff:ff:ff:ff:ff:ff

Now:

  $ ./ip link add index 10 type veth peer index -1
  Error: ifindex can't be negative.

This problem surfaced in net-next because an explicit WARN()
was added, the root cause is older.

Fixes: e6f8f1a739b6 ("veth: Allow to create peer link with given ifindex")
Fixes: a8f820a380a2 ("can: add Virtual CAN Tunnel driver (vxcan)")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
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