<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net/qrtr, branch master</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>net: qrtr: Send HELLO message on endpoint register</title>
<updated>2026-09-02T11:14:32+00:00</updated>
<author>
<name>Chris Lew</name>
<email>christopher.lew@oss.qualcomm.com</email>
</author>
<published>2026-08-27T12:18:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=544d85de4dc22c01badfd8cefa59829ce35c4858'/>
<id>544d85de4dc22c01badfd8cefa59829ce35c4858</id>
<content type='text'>
HELLO is currently handled entirely by the name server (NS): it is
sent once as a broadcast when the NS initializes, and again as a
reply whenever the NS receives an inbound HELLO from a remote.

Some remote QRTR endpoints (e.g. an external WLAN chipset attached
over MHI) operate in a slave role: they only ever send a HELLO in
response to one they receive, and never initiate. Since the host cannot
tell in advance which remotes behave this way, if the host also only
replies, both sides wait on the other to speak first and no HELLO is
ever exchanged, stalling further communication.

To fix this:
- Transfer HELLO handshake ownership to the core layer. A HELLO is
  now sent once, per endpoint, at registration time.
- Schedule a delayed work item on endpoint registration to send a
  HELLO once the name server is bound. The work reschedules itself
  with a 100ms backoff if the name server socket is not yet bound or
  if allocating the control packet fails, so a transient startup
  condition does not abandon the handshake permanently.
- Enforce HELLO-first ordering by dropping non-HELLO packets and
  returning -EAGAIN until the HELLO is confirmed sent, using bool
  hello_sent guarded by ep_lock to make the gate check atomic with
  xmit().
- Skip nodes with nid == QRTR_EP_NID_AUTO in bcast_enqueue(), to avoid
  broadcasting control packets with QRTR_EP_NID_AUTO as the destination
  node ID.
- Remove say_hello() from the name server's ctrl_cmd_hello() handler
  and from qrtr_ns_init(); the core layer is now the sole sender of
  the outbound HELLO. This removes the NS's reply-on-receive
  behaviour without a replacement.

Signed-off-by: Chris Lew &lt;christopher.lew@oss.qualcomm.com&gt;
Co-developed-by: Deepak Kumar Singh &lt;deepak.singh@oss.qualcomm.com&gt;
Signed-off-by: Deepak Kumar Singh &lt;deepak.singh@oss.qualcomm.com&gt;
Co-developed-by: Pranav Mahesh Phansalkar &lt;pranav.phansalkar@oss.qualcomm.com&gt;
Signed-off-by: Pranav Mahesh Phansalkar &lt;pranav.phansalkar@oss.qualcomm.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>
HELLO is currently handled entirely by the name server (NS): it is
sent once as a broadcast when the NS initializes, and again as a
reply whenever the NS receives an inbound HELLO from a remote.

Some remote QRTR endpoints (e.g. an external WLAN chipset attached
over MHI) operate in a slave role: they only ever send a HELLO in
response to one they receive, and never initiate. Since the host cannot
tell in advance which remotes behave this way, if the host also only
replies, both sides wait on the other to speak first and no HELLO is
ever exchanged, stalling further communication.

To fix this:
- Transfer HELLO handshake ownership to the core layer. A HELLO is
  now sent once, per endpoint, at registration time.
- Schedule a delayed work item on endpoint registration to send a
  HELLO once the name server is bound. The work reschedules itself
  with a 100ms backoff if the name server socket is not yet bound or
  if allocating the control packet fails, so a transient startup
  condition does not abandon the handshake permanently.
- Enforce HELLO-first ordering by dropping non-HELLO packets and
  returning -EAGAIN until the HELLO is confirmed sent, using bool
  hello_sent guarded by ep_lock to make the gate check atomic with
  xmit().
- Skip nodes with nid == QRTR_EP_NID_AUTO in bcast_enqueue(), to avoid
  broadcasting control packets with QRTR_EP_NID_AUTO as the destination
  node ID.
- Remove say_hello() from the name server's ctrl_cmd_hello() handler
  and from qrtr_ns_init(); the core layer is now the sole sender of
  the outbound HELLO. This removes the NS's reply-on-receive
  behaviour without a replacement.

Signed-off-by: Chris Lew &lt;christopher.lew@oss.qualcomm.com&gt;
Co-developed-by: Deepak Kumar Singh &lt;deepak.singh@oss.qualcomm.com&gt;
Signed-off-by: Deepak Kumar Singh &lt;deepak.singh@oss.qualcomm.com&gt;
Co-developed-by: Pranav Mahesh Phansalkar &lt;pranav.phansalkar@oss.qualcomm.com&gt;
Signed-off-by: Pranav Mahesh Phansalkar &lt;pranav.phansalkar@oss.qualcomm.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: qrtr: ns: Raise lookup limit to 128</title>
<updated>2026-08-06T15:10:44+00:00</updated>
<author>
<name>Łukasz Patron</name>
<email>priv.luk@gmail.com</email>
</author>
<published>2026-08-04T20:18:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7fc1c937b6b37c77df4ba374c37435ab06a2e945'/>
<id>7fc1c937b6b37c77df4ba374c37435ab06a2e945</id>
<content type='text'>
Current limit of 64 is not enough for Sony Xperia 10 VII (SM6475).

After merging v6.6.142 into a downstream AOSP device, it's stuck on
boot animation and following log spam can be observed in dmesg:

E qrtr    : ctrl_cmd_new_lookup(): QRTR client node exceeds max lookup limit!
E qrtr    : qrtr_ns_worker(): failed while handling packet from 1:16600

No idea why it needs more than 64 client lookups, but it appears to
work fine with 128 as it did when there were no limits.

I don't really have a good way to investigate what it needs all
these lookups for as most of the userspace is closed source.

Fixes: 5640227d9a21 ("net: qrtr: ns: Limit the maximum number of lookups")
Signed-off-by: Łukasz Patron &lt;priv.luk@gmail.com&gt;
Link: https://patch.msgid.link/20260804201919.1148015-1-priv.luk@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>
Current limit of 64 is not enough for Sony Xperia 10 VII (SM6475).

After merging v6.6.142 into a downstream AOSP device, it's stuck on
boot animation and following log spam can be observed in dmesg:

E qrtr    : ctrl_cmd_new_lookup(): QRTR client node exceeds max lookup limit!
E qrtr    : qrtr_ns_worker(): failed while handling packet from 1:16600

No idea why it needs more than 64 client lookups, but it appears to
work fine with 128 as it did when there were no limits.

I don't really have a good way to investigate what it needs all
these lookups for as most of the userspace is closed source.

Fixes: 5640227d9a21 ("net: qrtr: ns: Limit the maximum number of lookups")
Signed-off-by: Łukasz Patron &lt;priv.luk@gmail.com&gt;
Link: https://patch.msgid.link/20260804201919.1148015-1-priv.luk@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: qrtr: restrict socket creation to the initial network namespace</title>
<updated>2026-07-23T14:44:00+00:00</updated>
<author>
<name>Aldo Ariel Panzardo</name>
<email>qwe.aldo@gmail.com</email>
</author>
<published>2026-07-16T15:43:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3b536db8fb32da9e9c62f2bb45e2e319331f0426'/>
<id>3b536db8fb32da9e9c62f2bb45e2e319331f0426</id>
<content type='text'>
QRTR keeps its entire port and node state in module-global variables
that are not partitioned per network namespace: qrtr_local_nid is a
single global node id (always 1) and qrtr_ports is a single global
xarray. qrtr_port_lookup() and qrtr_local_enqueue() operate on that
global state with no network-namespace check, and qrtr_create() places
no restriction on the namespace a socket is created in.

As a result an unprivileged process that creates an AF_QIPCRTR socket
in a separate network namespace, e.g. via
unshare(CLONE_NEWUSER | CLONE_NEWNET), can send QRTR datagrams -
including control-plane messages such as QRTR_TYPE_NEW_SERVER - to QRTR
sockets owned by another namespace, and vice versa. The receiving
socket sees such a message as coming from node id 1, indistinguishable
from a legitimate local client, breaking the isolation that network
namespaces are expected to provide.

QRTR is a transport to global hardware endpoints (the modem and other
remote processors) and has no per-namespace semantics; its in-kernel
name service already creates its socket in init_net only. Confine the
socket family to the initial network namespace, as other
non-namespace-aware socket families do (see llc_ui_create() and the
ieee802154 socket code).

Fixes: bdabad3e363d ("net: Add Qualcomm IPC router")
Signed-off-by: Aldo Ariel Panzardo &lt;qwe.aldo@gmail.com&gt;
Link: https://patch.msgid.link/20260716154319.3297699-1-qwe.aldo@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>
QRTR keeps its entire port and node state in module-global variables
that are not partitioned per network namespace: qrtr_local_nid is a
single global node id (always 1) and qrtr_ports is a single global
xarray. qrtr_port_lookup() and qrtr_local_enqueue() operate on that
global state with no network-namespace check, and qrtr_create() places
no restriction on the namespace a socket is created in.

As a result an unprivileged process that creates an AF_QIPCRTR socket
in a separate network namespace, e.g. via
unshare(CLONE_NEWUSER | CLONE_NEWNET), can send QRTR datagrams -
including control-plane messages such as QRTR_TYPE_NEW_SERVER - to QRTR
sockets owned by another namespace, and vice versa. The receiving
socket sees such a message as coming from node id 1, indistinguishable
from a legitimate local client, breaking the isolation that network
namespaces are expected to provide.

QRTR is a transport to global hardware endpoints (the modem and other
remote processors) and has no per-namespace semantics; its in-kernel
name service already creates its socket in init_net only. Confine the
socket family to the initial network namespace, as other
non-namespace-aware socket families do (see llc_ui_create() and the
ieee802154 socket code).

Fixes: bdabad3e363d ("net: Add Qualcomm IPC router")
Signed-off-by: Aldo Ariel Panzardo &lt;qwe.aldo@gmail.com&gt;
Link: https://patch.msgid.link/20260716154319.3297699-1-qwe.aldo@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: qrtr: ns: Raise node count limit to 512</title>
<updated>2026-07-21T22:13:14+00:00</updated>
<author>
<name>Youssef Samir</name>
<email>youssef.abdulrahman@oss.qualcomm.com</email>
</author>
<published>2026-07-13T14:59:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ff194cffd586cbd4cc49eccb002c65f2a902a277'/>
<id>ff194cffd586cbd4cc49eccb002c65f2a902a277</id>
<content type='text'>
The current node limit of 64 breaks the functionality for a number of AI200
deployments that have up to 384 nodes. Raise the limit to 512.

Fixes: 27d5e84e810b ("net: qrtr: ns: Limit the total number of nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Youssef Samir &lt;youssef.abdulrahman@oss.qualcomm.com&gt;
Link: https://patch.msgid.link/20260713145901.212396-1-youssef.abdulrahman@oss.qualcomm.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The current node limit of 64 breaks the functionality for a number of AI200
deployments that have up to 384 nodes. Raise the limit to 512.

Fixes: 27d5e84e810b ("net: qrtr: ns: Limit the total number of nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Youssef Samir &lt;youssef.abdulrahman@oss.qualcomm.com&gt;
Link: https://patch.msgid.link/20260713145901.212396-1-youssef.abdulrahman@oss.qualcomm.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Replace &lt;linux/mod_devicetable.h&gt; by more specific &lt;linux/device-id/*.h&gt; (c files)</title>
<updated>2026-07-03T05:38:17+00:00</updated>
<author>
<name>Uwe Kleine-König (The Capable Hub)</name>
<email>u.kleine-koenig@baylibre.com</email>
</author>
<published>2026-06-30T09:24:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=995832b2cebe6969d1b42635db698803ee31294d'/>
<id>995832b2cebe6969d1b42635db698803ee31294d</id>
<content type='text'>
Replace the #include of &lt;linux/mod_devicetable.h&gt; by the more specific
&lt;linux/device-id/*.h&gt; where applicable. For most cases the include
can be dropped completely, only a few drivers need one or two headers
added.

Acked-by: Danilo Krummrich &lt;dakr@kernel.org&gt;
Acked-by: Takashi Sakamoto &lt;o-takashi@sakamocchi.jp&gt;
Acked-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Link: https://patch.msgid.link/1a3f2007c5c5dcf555c09a4035ce3ae8ef1b6c49.1782808461.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König (The Capable Hub) &lt;u.kleine-koenig@baylibre.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Replace the #include of &lt;linux/mod_devicetable.h&gt; by the more specific
&lt;linux/device-id/*.h&gt; where applicable. For most cases the include
can be dropped completely, only a few drivers need one or two headers
added.

Acked-by: Danilo Krummrich &lt;dakr@kernel.org&gt;
Acked-by: Takashi Sakamoto &lt;o-takashi@sakamocchi.jp&gt;
Acked-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Link: https://patch.msgid.link/1a3f2007c5c5dcf555c09a4035ce3ae8ef1b6c49.1782808461.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König (The Capable Hub) &lt;u.kleine-koenig@baylibre.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2026-06-16T21:59:58+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2026-06-16T21:57:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d755d45bc08a57a3b845b850f8760de922a499bf'/>
<id>d755d45bc08a57a3b845b850f8760de922a499bf</id>
<content type='text'>
Merge in late fixes in preparation for the net-next PR.

Conflicts:

net/tls/tls_sw.c
  406e8a651a7b ("net: skmsg: preserve sg.copy across SG transforms")
  79511603a65b ("tls: remove dead sockmap (psock) handling from the SW path")

drivers/net/ethernet/microsoft/mana/mana_en.c
  f8fd56977eeea ("net: mana: guard TX wq object destroy with INVALID_MANA_HANDLE check")
  d07efe5a6e641 ("net: mana: Use per-queue allocation for tx_qp to reduce allocation size")
https://lore.kernel.org/ajAPXu-C_PuTgV-a@sirena.org.uk

No adjacent changes.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge in late fixes in preparation for the net-next PR.

Conflicts:

net/tls/tls_sw.c
  406e8a651a7b ("net: skmsg: preserve sg.copy across SG transforms")
  79511603a65b ("tls: remove dead sockmap (psock) handling from the SW path")

drivers/net/ethernet/microsoft/mana/mana_en.c
  f8fd56977eeea ("net: mana: guard TX wq object destroy with INVALID_MANA_HANDLE check")
  d07efe5a6e641 ("net: mana: Use per-queue allocation for tx_qp to reduce allocation size")
https://lore.kernel.org/ajAPXu-C_PuTgV-a@sirena.org.uk

No adjacent changes.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: qrtr: fix 32-bit integer overflow in qrtr_endpoint_post()</title>
<updated>2026-06-13T01:42:53+00:00</updated>
<author>
<name>Michael Bommarito</name>
<email>michael.bommarito@gmail.com</email>
</author>
<published>2026-06-11T12:54:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=20054869770c7df060c5ecee3e8bbf9029c47191'/>
<id>20054869770c7df060c5ecee3e8bbf9029c47191</id>
<content type='text'>
qrtr_endpoint_post() validates an incoming packet with

	if (!size || len != ALIGN(size, 4) + hdrlen)
		goto err;

where size comes from the wire. On 32-bit, size_t is 32 bits and
ALIGN(size, 4) wraps to 0 for size &gt;= 0xfffffffd, so the check
passes and skb_put_data(skb, data + hdrlen, size) writes past the
hdrlen-sized skb and oopses the kernel. 64-bit is unaffected.

This is the 32-bit residual of ad9d24c9429e2 ("net: qrtr: fix OOB
Read in qrtr_endpoint_post"), which fixed only the 64-bit case.

Reject any size that cannot fit the buffer before the ALIGN.

Fixes: ad9d24c9429e2 ("net: qrtr: fix OOB Read in qrtr_endpoint_post")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Bommarito &lt;michael.bommarito@gmail.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20260611125455.2352279-1-michael.bommarito@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>
qrtr_endpoint_post() validates an incoming packet with

	if (!size || len != ALIGN(size, 4) + hdrlen)
		goto err;

where size comes from the wire. On 32-bit, size_t is 32 bits and
ALIGN(size, 4) wraps to 0 for size &gt;= 0xfffffffd, so the check
passes and skb_put_data(skb, data + hdrlen, size) writes past the
hdrlen-sized skb and oopses the kernel. 64-bit is unaffected.

This is the 32-bit residual of ad9d24c9429e2 ("net: qrtr: fix OOB
Read in qrtr_endpoint_post"), which fixed only the 64-bit case.

Reject any size that cannot fit the buffer before the ALIGN.

Fixes: ad9d24c9429e2 ("net: qrtr: fix OOB Read in qrtr_endpoint_post")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Bommarito &lt;michael.bommarito@gmail.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20260611125455.2352279-1-michael.bommarito@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>2026-06-11T21:33:35+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2026-06-11T21:29:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dad4d4b92a9b9f0edb8c66deda049da1b62f6089'/>
<id>dad4d4b92a9b9f0edb8c66deda049da1b62f6089</id>
<content type='text'>
Cross-merge networking fixes after downstream PR (net-7.1-rc8).

Conflicts:

drivers/net/ethernet/wangxun/txgbe/txgbe_aml.c
  f67aead16e85 ("net: txgbe: rework service event handling")
  57d39faed4c9 ("net: txgbe: improve functions of AML 40G devices")

net/rds/info.c
  512db8267b73 ("rds: mark snapshot pages dirty in rds_info_getsockopt()")
  6e94eeb2a2a6 ("rds: convert to getsockopt_iter")

Adjacent changes:

include/net/sock.h
  1ee90b77b727 ("net: guard timestamp cmsgs to real error queue skbs")
  f0de88303d5e ("net: make is_skb_wmem() available to modules")

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 (net-7.1-rc8).

Conflicts:

drivers/net/ethernet/wangxun/txgbe/txgbe_aml.c
  f67aead16e85 ("net: txgbe: rework service event handling")
  57d39faed4c9 ("net: txgbe: improve functions of AML 40G devices")

net/rds/info.c
  512db8267b73 ("rds: mark snapshot pages dirty in rds_info_getsockopt()")
  6e94eeb2a2a6 ("rds: convert to getsockopt_iter")

Adjacent changes:

include/net/sock.h
  1ee90b77b727 ("net: guard timestamp cmsgs to real error queue skbs")
  f0de88303d5e ("net: make is_skb_wmem() available to modules")

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove</title>
<updated>2026-06-09T01:45:38+00:00</updated>
<author>
<name>Mingyu Wang</name>
<email>25181214217@stu.xidian.edu.cn</email>
</author>
<published>2026-06-04T06:48:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a2171131ecda1ed61a594a1eb715e75fdad0fef5'/>
<id>a2171131ecda1ed61a594a1eb715e75fdad0fef5</id>
<content type='text'>
In qrtr_port_remove(), the socket reference count is decremented via
__sock_put() before the port is removed from the qrtr_ports XArray and
before the RCU grace period elapses.

This breaks the fundamental RCU update paradigm. It exposes a race
window where a concurrent RCU reader (such as qrtr_reset_ports() or
qrtr_port_lookup()) can obtain a pointer to the socket from the XArray,
and attempt to call sock_hold() on a socket whose reference count has
already dropped to zero.

This exact race condition was hit during syzkaller fuzzing, leading to
the following refcount saturation warning and a potential Use-After-Free:

  refcount_t: saturated; leaking memory.
  WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0
  Modules linked in: qrtr(+) bochs drm_shmem_helper ...
  Call Trace:
   &lt;TASK&gt;
   qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr]
   __qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr]
   qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr]
   kernel_bind+0xe4/0x120 net/socket.c:3592
   qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr]
   qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr]
   do_one_initcall+0xf5/0x5e0 init/main.c:1283
   ...
   &lt;/TASK&gt;

Fix this by deferring the reference count decrement until after the
xa_erase() and the synchronize_rcu() complete.

(Note: The v1 of this patch incorrectly replaced __sock_put() with
sock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove()
still hold a reference to the socket, so freeing the socket memory here
would lead to a subsequent UAF in the caller. Thus, the __sock_put() is
kept, but only repositioned to close the RCU race.)

Fixes: bdabad3e363d ("net: Add Qualcomm IPC router")
Signed-off-by: Mingyu Wang &lt;25181214217@stu.xidian.edu.cn&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20260604064801.1180388-1-w15303746062@163.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In qrtr_port_remove(), the socket reference count is decremented via
__sock_put() before the port is removed from the qrtr_ports XArray and
before the RCU grace period elapses.

This breaks the fundamental RCU update paradigm. It exposes a race
window where a concurrent RCU reader (such as qrtr_reset_ports() or
qrtr_port_lookup()) can obtain a pointer to the socket from the XArray,
and attempt to call sock_hold() on a socket whose reference count has
already dropped to zero.

This exact race condition was hit during syzkaller fuzzing, leading to
the following refcount saturation warning and a potential Use-After-Free:

  refcount_t: saturated; leaking memory.
  WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0
  Modules linked in: qrtr(+) bochs drm_shmem_helper ...
  Call Trace:
   &lt;TASK&gt;
   qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr]
   __qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr]
   qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr]
   kernel_bind+0xe4/0x120 net/socket.c:3592
   qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr]
   qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr]
   do_one_initcall+0xf5/0x5e0 init/main.c:1283
   ...
   &lt;/TASK&gt;

Fix this by deferring the reference count decrement until after the
xa_erase() and the synchronize_rcu() complete.

(Note: The v1 of this patch incorrectly replaced __sock_put() with
sock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove()
still hold a reference to the socket, so freeing the socket memory here
would lead to a subsequent UAF in the caller. Thus, the __sock_put() is
kept, but only repositioned to close the RCU race.)

Fixes: bdabad3e363d ("net: Add Qualcomm IPC router")
Signed-off-by: Mingyu Wang &lt;25181214217@stu.xidian.edu.cn&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20260604064801.1180388-1-w15303746062@163.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: qrtr: fix node refcount leak on ctrl packet alloc failure</title>
<updated>2026-06-02T02:53:45+00:00</updated>
<author>
<name>Wentao Liang</name>
<email>vulab@iscas.ac.cn</email>
</author>
<published>2026-05-28T08:00:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3b09ff54114566864eea59020f6b69c5bb325b9d'/>
<id>3b09ff54114566864eea59020f6b69c5bb325b9d</id>
<content type='text'>
qrtr_send_resume_tx() calls qrtr_node_lookup() which takes a
reference on the returned node. If the subsequent call to
qrtr_alloc_ctrl_packet() fails due to memory allocation failure, the
function returns -ENOMEM without calling qrtr_node_release() to
release the node reference.

Add qrtr_node_release(node) before returning on the allocation failure
path to properly release the reference.

Signed-off-by: Wentao Liang &lt;vulab@iscas.ac.cn&gt;
Reviewed-by: Alexander Lobakin &lt;aleksander.lobakin@intel.com&gt;
Reviewed-by: Manivannan Sadhasivam &lt;mani@kernel.org&gt;
Link: https://patch.msgid.link/20260528080019.1176700-1-vulab@iscas.ac.cn
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
qrtr_send_resume_tx() calls qrtr_node_lookup() which takes a
reference on the returned node. If the subsequent call to
qrtr_alloc_ctrl_packet() fails due to memory allocation failure, the
function returns -ENOMEM without calling qrtr_node_release() to
release the node reference.

Add qrtr_node_release(node) before returning on the allocation failure
path to properly release the reference.

Signed-off-by: Wentao Liang &lt;vulab@iscas.ac.cn&gt;
Reviewed-by: Alexander Lobakin &lt;aleksander.lobakin@intel.com&gt;
Reviewed-by: Manivannan Sadhasivam &lt;mani@kernel.org&gt;
Link: https://patch.msgid.link/20260528080019.1176700-1-vulab@iscas.ac.cn
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
