<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/git/stable/linux.git/net/dsa, branch linux-5.4.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<id>https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-5.4.y</id>
<link rel='self' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/atom?h=linux-5.4.y'/>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/'/>
<updated>2025-09-09T16:44:00+00:00</updated>
<entry>
<title>net: dsa: microchip: linearize skb for tail-tagging switches</title>
<updated>2025-09-09T16:44:00+00:00</updated>
<author>
<name>Jakob Unterwurzacher</name>
<email>jakobunt@gmail.com</email>
</author>
<published>2025-09-05T19:22:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=26dc498a9fe8acc71d0774ac91f37d27d84bf56c'/>
<id>urn:sha1:26dc498a9fe8acc71d0774ac91f37d27d84bf56c</id>
<content type='text'>
[ Upstream commit ba54bce747fa9e07896c1abd9b48545f7b4b31d2 ]

The pointer arithmentic for accessing the tail tag only works
for linear skbs.

For nonlinear skbs, it reads uninitialized memory inside the
skb headroom, essentially randomizing the tag. I have observed
it gets set to 6 most of the time.

Example where ksz9477_rcv thinks that the packet from port 1 comes from port 6
(which does not exist for the ksz9896 that's in use), dropping the packet.
Debug prints added by me (not included in this patch):

	[  256.645337] ksz9477_rcv:323 tag0=6
	[  256.645349] skb len=47 headroom=78 headlen=0 tailroom=0
	               mac=(64,14) mac_len=14 net=(78,0) trans=78
	               shinfo(txflags=0 nr_frags=1 gso(size=0 type=0 segs=0))
	               csum(0x0 start=0 offset=0 ip_summed=0 complete_sw=0 valid=0 level=0)
	               hash(0x0 sw=0 l4=0) proto=0x00f8 pkttype=1 iif=3
	               priority=0x0 mark=0x0 alloc_cpu=0 vlan_all=0x0
	               encapsulation=0 inner(proto=0x0000, mac=0, net=0, trans=0)
	[  256.645377] dev name=end1 feat=0x0002e10200114bb3
	[  256.645386] skb headroom: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
	[  256.645395] skb headroom: 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
	[  256.645403] skb headroom: 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
	[  256.645411] skb headroom: 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
	[  256.645420] skb headroom: 00000040: ff ff ff ff ff ff 00 1c 19 f2 e2 db 08 06
	[  256.645428] skb frag:     00000000: 00 01 08 00 06 04 00 01 00 1c 19 f2 e2 db 0a 02
	[  256.645436] skb frag:     00000010: 00 83 00 00 00 00 00 00 0a 02 a0 2f 00 00 00 00
	[  256.645444] skb frag:     00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01
	[  256.645452] ksz_common_rcv:92 dsa_conduit_find_user returned NULL

Call skb_linearize before trying to access the tag.

This patch fixes ksz9477_rcv which is used by the ksz9896 I have at
hand, and also applies the same fix to ksz8795_rcv which seems to have
the same problem.

Signed-off-by: Jakob Unterwurzacher &lt;jakob.unterwurzacher@cherry.de&gt;
CC: stable@vger.kernel.org
Fixes: 016e43a26bab ("net: dsa: ksz: Add KSZ8795 tag code")
Fixes: 8b8010fb7876 ("dsa: add support for Microchip KSZ tail tagging")
Reviewed-by: Vladimir Oltean &lt;olteanv@gmail.com&gt;
Link: https://patch.msgid.link/20250515072920.2313014-1-jakob.unterwurzacher@cherry.de
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: microchip: update tag_ksz masks for KSZ9477 family</title>
<updated>2025-09-09T16:44:00+00:00</updated>
<author>
<name>Pieter Van Trappen</name>
<email>pieter.van.trappen@cern.ch</email>
</author>
<published>2025-09-05T19:22:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=183037e841367334b21296a1d628aeef383dbde2'/>
<id>urn:sha1:183037e841367334b21296a1d628aeef383dbde2</id>
<content type='text'>
[ Upstream commit 3f464b193d40e49299dcd087b10cc3b77cbbea68 ]

Remove magic number 7 by introducing a GENMASK macro instead.
Remove magic number 0x80 by using the BIT macro instead.

Signed-off-by: Pieter Van Trappen &lt;pieter.van.trappen@cern.ch&gt;
Reviewed-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Link: https://patch.msgid.link/20240909134301.75448-1-vtpieter@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: ba54bce747fa ("net: dsa: microchip: linearize skb for tail-tagging switches")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: tag_sja1105: fix MAC DA patching from meta frames</title>
<updated>2023-07-27T06:37:24+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2023-07-03T22:05:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=58b1b3c54e16223c3c1e5a503cce21eab54ed7e3'/>
<id>urn:sha1:58b1b3c54e16223c3c1e5a503cce21eab54ed7e3</id>
<content type='text'>
[ Upstream commit 1dcf6efd5f0c1f4496b3ef7ec5a7db104a53b38c ]

The SJA1105 manual says that at offset 4 into the meta frame payload we
have "MAC destination byte 2" and at offset 5 we have "MAC destination
byte 1". These are counted from the LSB, so byte 1 is h_dest[ETH_HLEN-2]
aka h_dest[4] and byte 2 is h_dest[ETH_HLEN-3] aka h_dest[3].

The sja1105_meta_unpack() function decodes these the other way around,
so a frame with MAC DA 01:80:c2:11:22:33 is received by the network
stack as having 01:80:c2:22:11:33.

Fixes: e53e18a6fe4d ("net: dsa: sja1105: Receive and decode meta frames")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@corigine.com&gt;
Reviewed-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: ksz: Check return value</title>
<updated>2022-12-14T10:30:45+00:00</updated>
<author>
<name>Artem Chernyshev</name>
<email>artem.chernyshev@red-soft.ru</email>
</author>
<published>2022-12-01T14:00:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0834d4b121e73fb7db192b6e81fa54bcff4c7681'/>
<id>urn:sha1:0834d4b121e73fb7db192b6e81fa54bcff4c7681</id>
<content type='text'>
[ Upstream commit 3d8fdcbf1f42e2bb9ae8b8c0b6f202278c788a22 ]

Return NULL if we got unexpected value from skb_trim_rcsum()
in ksz_common_rcv()

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: bafe9ba7d908 ("net: dsa: ksz: Factor out common tag code")
Signed-off-by: Artem Chernyshev &lt;artem.chernyshev@red-soft.ru&gt;
Reviewed-by: Vladimir Oltean &lt;olteanv@gmail.com&gt;
Reviewed-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Link: https://lore.kernel.org/r/20221201140032.26746-1-artem.chernyshev@red-soft.ru
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: Add missing of_node_put() in dsa_port_parse_of</title>
<updated>2022-03-23T08:12:07+00:00</updated>
<author>
<name>Miaoqian Lin</name>
<email>linmq006@gmail.com</email>
</author>
<published>2022-03-16T08:26:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d7b92963752718baaf2ff43573204e0de09e3505'/>
<id>urn:sha1:d7b92963752718baaf2ff43573204e0de09e3505</id>
<content type='text'>
[ Upstream commit cb0b430b4e3acc88c85e0ad2e25f2a25a5765262 ]

The device_node pointer is returned by of_parse_phandle()  with refcount
incremented. We should use of_node_put() on it when done.

Fixes: 6d4e5c570c2d ("net: dsa: get port type at parse time")
Signed-off-by: Miaoqian Lin &lt;linmq006@gmail.com&gt;
Link: https://lore.kernel.org/r/20220316082602.10785-1-linmq006@gmail.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: destroy the phylink instance on any error in dsa_slave_phy_setup</title>
<updated>2021-09-22T10:26:42+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2021-09-14T13:43:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=baf450477143360570bf6581c226912da2862f54'/>
<id>urn:sha1:baf450477143360570bf6581c226912da2862f54</id>
<content type='text'>
commit 6a52e73368038f47f6618623d75061dc263b26ae upstream.

DSA supports connecting to a phy-handle, and has a fallback to a non-OF
based method of connecting to an internal PHY on the switch's own MDIO
bus, if no phy-handle and no fixed-link nodes were present.

The -ENODEV error code from the first attempt (phylink_of_phy_connect)
is what triggers the second attempt (phylink_connect_phy).

However, when the first attempt returns a different error code than
-ENODEV, this results in an unbalance of calls to phylink_create and
phylink_destroy by the time we exit the function. The phylink instance
has leaked.

There are many other error codes that can be returned by
phylink_of_phy_connect. For example, phylink_validate returns -EINVAL.
So this is a practical issue too.

Fixes: aab9c4067d23 ("net: dsa: Plug in PHYLINK support")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Reviewed-by: Russell King (Oracle) &lt;rmk+kernel@armlinux.org.uk&gt;
Link: https://lore.kernel.org/r/20210914134331.2303380-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: fix error code getting shifted with 4 in dsa_slave_get_sset_count</title>
<updated>2021-06-03T06:59:12+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2021-05-09T19:33:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=87803141fb3e5d74ab0f624690bde55c577cedfe'/>
<id>urn:sha1:87803141fb3e5d74ab0f624690bde55c577cedfe</id>
<content type='text'>
[ Upstream commit b94cbc909f1d80378a1f541968309e5c1178c98b ]

DSA implements a bunch of 'standardized' ethtool statistics counters,
namely tx_packets, tx_bytes, rx_packets, rx_bytes. So whatever the
hardware driver returns in .get_sset_count(), we need to add 4 to that.

That is ok, except that .get_sset_count() can return a negative error
code, for example:

b53_get_sset_count
-&gt; phy_ethtool_get_sset_count
   -&gt; return -EIO

-EIO is -5, and with 4 added to it, it becomes -1, aka -EPERM. One can
imagine that certain error codes may even become positive, although
based on code inspection I did not see instances of that.

Check the error code first, if it is negative return it as-is.

Based on a similar patch for dsa_master_get_strings from Dan Carpenter:
https://patchwork.kernel.org/project/netdevbpf/patch/YJaSe3RPgn7gKxZv@mwanda/

Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: dsa: fix a crash if -&gt;get_sset_count() fails</title>
<updated>2021-06-03T06:59:07+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2021-05-08T13:30:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ce5355f140a7987011388c7e30c4f8fbe180d3e8'/>
<id>urn:sha1:ce5355f140a7987011388c7e30c4f8fbe180d3e8</id>
<content type='text'>
commit a269333fa5c0c8e53c92b5a28a6076a28cde3e83 upstream.

If ds-&gt;ops-&gt;get_sset_count() fails then it "count" is a negative error
code such as -EOPNOTSUPP.  Because "i" is an unsigned int, the negative
error code is type promoted to a very high value and the loop will
corrupt memory until the system crashes.

Fix this by checking for error codes and changing the type of "i" to
just int.

Fixes: badf3ada60ab ("net: dsa: Provide CPU port statistics to master netdev")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Reviewed-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Reviewed-by: Vladimir Oltean &lt;olteanv@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>
</entry>
<entry>
<title>net: dsa: tag_mtk: fix 802.1ad VLAN egress</title>
<updated>2021-03-20T09:39:47+00:00</updated>
<author>
<name>DENG Qingfang</name>
<email>dqfext@gmail.com</email>
</author>
<published>2021-03-01T16:01:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ebeefdc3d8eeded86e88eb2a2f0da2239f1d2f36'/>
<id>urn:sha1:ebeefdc3d8eeded86e88eb2a2f0da2239f1d2f36</id>
<content type='text'>
commit 9200f515c41f4cbaeffd8fdd1d8b6373a18b1b67 upstream.

A different TPID bit is used for 802.1ad VLAN frames.

Reported-by: Ilario Gelmetti &lt;iochesonome@gmail.com&gt;
Fixes: f0af34317f4b ("net: dsa: mediatek: combine MediaTek tag with VLAN tag")
Signed-off-by: DENG Qingfang &lt;dqfext@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>
</entry>
<entry>
<title>net: dsa: add GRO support via gro_cells</title>
<updated>2021-03-11T13:06:48+00:00</updated>
<author>
<name>Alexander Lobakin</name>
<email>bloodyreaper@yandex.ru</email>
</author>
<published>2020-04-21T13:41:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.rulkc.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c1f5fc082beb8653f814711b838b51186cc696e2'/>
<id>urn:sha1:c1f5fc082beb8653f814711b838b51186cc696e2</id>
<content type='text'>
commit e131a5634830047923c694b4ce0c3b31745ff01b upstream.

gro_cells lib is used by different encapsulating netdevices, such as
geneve, macsec, vxlan etc. to speed up decapsulated traffic processing.
CPU tag is a sort of "encapsulation", and we can use the same mechs to
greatly improve overall DSA performance.
skbs are passed to the GRO layer after removing CPU tags, so we don't
need any new packet offload types as it was firstly proposed by me in
the first GRO-over-DSA variant [1].

The size of struct gro_cells is sizeof(void *), so hot struct
dsa_slave_priv becomes only 4/8 bytes bigger, and all critical fields
remain in one 32-byte cacheline.
The other positive side effect is that drivers for network devices
that can be shipped as CPU ports of DSA-driven switches can now use
napi_gro_frags() to pass skbs to kernel. Packets built that way are
completely non-linear and are likely being dropped without GRO.

This was tested on to-be-mainlined-soon Ethernet driver that uses
napi_gro_frags(), and the overall performance was on par with the
variant from [1], sometimes even better due to minimal overhead.
net.core.gro_normal_batch tuning may help to push it to the limit
on particular setups and platforms.

iperf3 IPoE VLAN NAT TCP forwarding (port1.218 -&gt; port0) setup
on 1.2 GHz MIPS board:

5.7-rc2 baseline:

[ID]  Interval         Transfer     Bitrate        Retr
[ 5]  0.00-120.01 sec  9.00 GBytes  644 Mbits/sec  413  sender
[ 5]  0.00-120.00 sec  8.99 GBytes  644 Mbits/sec       receiver

Iface      RX packets  TX packets
eth0       7097731     7097702
port0      426050      6671829
port1      6671681     425862
port1.218  6671677     425851

With this patch:

[ID]  Interval         Transfer     Bitrate        Retr
[ 5]  0.00-120.01 sec  12.2 GBytes  870 Mbits/sec  122  sender
[ 5]  0.00-120.00 sec  12.2 GBytes  870 Mbits/sec       receiver

Iface      RX packets  TX packets
eth0       9474792     9474777
port0      455200      353288
port1      9019592     455035
port1.218  353144      455024

v2:
 - Add some performance examples in the commit message;
 - No functional changes.

[1] https://lore.kernel.org/netdev/20191230143028.27313-1-alobakin@dlink.ru/

Signed-off-by: Alexander Lobakin &lt;bloodyreaper@yandex.ru&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
