<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net/mac80211, branch v6.10-rc6</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>wifi: mac80211: fix monitor channel with chanctx emulation</title>
<updated>2024-06-14T07:14:08+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2024-06-12T10:23:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=0d9c2beed116e623ac30810d382bd67163650f98'/>
<id>0d9c2beed116e623ac30810d382bd67163650f98</id>
<content type='text'>
After the channel context emulation, there were reports that
changing the monitor channel no longer works. This is because
those drivers don't have WANT_MONITOR_VIF, so the setting the
channel always exits out quickly.

Fix this by always allocating the virtual monitor sdata, and
simply not telling the driver about it unless it wanted to.
This way, we have an interface/sdata to bind the chanctx to,
and the emulation can work correctly.

Cc: stable@vger.kernel.org
Fixes: 0a44dfc07074 ("wifi: mac80211: simplify non-chanctx drivers")
Reported-and-tested-by: Savyasaachi Vanga &lt;savyasaachiv@gmail.com&gt;
Closes: https://lore.kernel.org/r/chwoymvpzwtbmzryrlitpwmta5j6mtndocxsyqvdyikqu63lon@gfds653hkknl
Link: https://msgid.link/20240612122351.b12d4a109dde.I1831a44417faaab92bea1071209abbe4efbe3fba@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After the channel context emulation, there were reports that
changing the monitor channel no longer works. This is because
those drivers don't have WANT_MONITOR_VIF, so the setting the
channel always exits out quickly.

Fix this by always allocating the virtual monitor sdata, and
simply not telling the driver about it unless it wanted to.
This way, we have an interface/sdata to bind the chanctx to,
and the emulation can work correctly.

Cc: stable@vger.kernel.org
Fixes: 0a44dfc07074 ("wifi: mac80211: simplify non-chanctx drivers")
Reported-and-tested-by: Savyasaachi Vanga &lt;savyasaachiv@gmail.com&gt;
Closes: https://lore.kernel.org/r/chwoymvpzwtbmzryrlitpwmta5j6mtndocxsyqvdyikqu63lon@gfds653hkknl
Link: https://msgid.link/20240612122351.b12d4a109dde.I1831a44417faaab92bea1071209abbe4efbe3fba@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: Avoid address calculations via out of bounds array indexing</title>
<updated>2024-06-14T07:08:41+00:00</updated>
<author>
<name>Kenton Groombridge</name>
<email>concord@gentoo.org</email>
</author>
<published>2024-06-05T15:22:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=2663d0462eb32ae7c9b035300ab6b1523886c718'/>
<id>2663d0462eb32ae7c9b035300ab6b1523886c718</id>
<content type='text'>
req-&gt;n_channels must be set before req-&gt;channels[] can be used.

This patch fixes one of the issues encountered in [1].

[   83.964255] UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:364:4
[   83.964258] index 0 is out of range for type 'struct ieee80211_channel *[]'
[...]
[   83.964264] Call Trace:
[   83.964267]  &lt;TASK&gt;
[   83.964269]  dump_stack_lvl+0x3f/0xc0
[   83.964274]  __ubsan_handle_out_of_bounds+0xec/0x110
[   83.964278]  ieee80211_prep_hw_scan+0x2db/0x4b0
[   83.964281]  __ieee80211_start_scan+0x601/0x990
[   83.964291]  nl80211_trigger_scan+0x874/0x980
[   83.964295]  genl_family_rcv_msg_doit+0xe8/0x160
[   83.964298]  genl_rcv_msg+0x240/0x270
[...]

[1] https://bugzilla.kernel.org/show_bug.cgi?id=218810

Co-authored-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
Signed-off-by: Kenton Groombridge &lt;concord@gentoo.org&gt;
Link: https://msgid.link/20240605152218.236061-1-concord@gentoo.org
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
req-&gt;n_channels must be set before req-&gt;channels[] can be used.

This patch fixes one of the issues encountered in [1].

[   83.964255] UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:364:4
[   83.964258] index 0 is out of range for type 'struct ieee80211_channel *[]'
[...]
[   83.964264] Call Trace:
[   83.964267]  &lt;TASK&gt;
[   83.964269]  dump_stack_lvl+0x3f/0xc0
[   83.964274]  __ubsan_handle_out_of_bounds+0xec/0x110
[   83.964278]  ieee80211_prep_hw_scan+0x2db/0x4b0
[   83.964281]  __ieee80211_start_scan+0x601/0x990
[   83.964291]  nl80211_trigger_scan+0x874/0x980
[   83.964295]  genl_family_rcv_msg_doit+0xe8/0x160
[   83.964298]  genl_rcv_msg+0x240/0x270
[...]

[1] https://bugzilla.kernel.org/show_bug.cgi?id=218810

Co-authored-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
Signed-off-by: Kenton Groombridge &lt;concord@gentoo.org&gt;
Link: https://msgid.link/20240605152218.236061-1-concord@gentoo.org
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: Recalc offload when monitor stop</title>
<updated>2024-06-12T10:29:25+00:00</updated>
<author>
<name>Remi Pommarel</name>
<email>repk@triplefau.lt</email>
</author>
<published>2024-05-18T16:07:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7d09e17c0415fe6d946044c7e70bce31cda952ec'/>
<id>7d09e17c0415fe6d946044c7e70bce31cda952ec</id>
<content type='text'>
When a monitor interface is started, ieee80211_recalc_offload() is
called and 802.11 encapsulation offloading support get disabled so
monitor interface could get native wifi frames directly. But when
this interface is stopped there is no need to keep the 802.11
encpasulation offloading off.

This call ieee80211_recalc_offload() when monitor interface is stopped
so 802.11 encapsulation offloading gets re-activated if possible.

Fixes: 6aea26ce5a4c ("mac80211: rework tx encapsulation offload API")
Signed-off-by: Remi Pommarel &lt;repk@triplefau.lt&gt;
Link: https://msgid.link/840baab454f83718e6e16fd836ac597d924e85b9.1716048326.git.repk@triplefau.lt
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When a monitor interface is started, ieee80211_recalc_offload() is
called and 802.11 encapsulation offloading support get disabled so
monitor interface could get native wifi frames directly. But when
this interface is stopped there is no need to keep the 802.11
encpasulation offloading off.

This call ieee80211_recalc_offload() when monitor interface is stopped
so 802.11 encapsulation offloading gets re-activated if possible.

Fixes: 6aea26ce5a4c ("mac80211: rework tx encapsulation offload API")
Signed-off-by: Remi Pommarel &lt;repk@triplefau.lt&gt;
Link: https://msgid.link/840baab454f83718e6e16fd836ac597d924e85b9.1716048326.git.repk@triplefau.lt
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: fix UBSAN noise in ieee80211_prep_hw_scan()</title>
<updated>2024-05-29T13:58:54+00:00</updated>
<author>
<name>Dmitry Antipov</name>
<email>dmantipov@yandex.ru</email>
</author>
<published>2024-05-17T15:33:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=92ecbb3ac6f3fe8ae9edf3226c76aa17b6800699'/>
<id>92ecbb3ac6f3fe8ae9edf3226c76aa17b6800699</id>
<content type='text'>
When testing the previous patch with CONFIG_UBSAN_BOUNDS, I've
noticed the following:

UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:372:4
index 0 is out of range for type 'struct ieee80211_channel *[]'
CPU: 0 PID: 1435 Comm: wpa_supplicant Not tainted 6.9.0+ #1
Hardware name: LENOVO 20UN005QRT/20UN005QRT &lt;...BIOS details...&gt;
Call Trace:
 &lt;TASK&gt;
 dump_stack_lvl+0x2d/0x90
 __ubsan_handle_out_of_bounds+0xe7/0x140
 ? timerqueue_add+0x98/0xb0
 ieee80211_prep_hw_scan+0x2db/0x480 [mac80211]
 ? __kmalloc+0xe1/0x470
 __ieee80211_start_scan+0x541/0x760 [mac80211]
 rdev_scan+0x1f/0xe0 [cfg80211]
 nl80211_trigger_scan+0x9b6/0xae0 [cfg80211]
 ...&lt;the rest is not too useful...&gt;

Since '__ieee80211_start_scan()' leaves 'hw_scan_req-&gt;req.n_channels'
uninitialized, actual boundaries of 'hw_scan_req-&gt;req.channels' can't
be checked in 'ieee80211_prep_hw_scan()'. Although an initialization
of 'hw_scan_req-&gt;req.n_channels' introduces some confusion around
allocated vs. used VLA members, this shouldn't be a problem since
everything is correctly adjusted soon in 'ieee80211_prep_hw_scan()'.

Cleanup 'kmalloc()' math in '__ieee80211_start_scan()' by using the
convenient 'struct_size()' as well.

Signed-off-by: Dmitry Antipov &lt;dmantipov@yandex.ru&gt;
Link: https://msgid.link/20240517153332.18271-2-dmantipov@yandex.ru
[improve (imho) indentation a bit]
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When testing the previous patch with CONFIG_UBSAN_BOUNDS, I've
noticed the following:

UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:372:4
index 0 is out of range for type 'struct ieee80211_channel *[]'
CPU: 0 PID: 1435 Comm: wpa_supplicant Not tainted 6.9.0+ #1
Hardware name: LENOVO 20UN005QRT/20UN005QRT &lt;...BIOS details...&gt;
Call Trace:
 &lt;TASK&gt;
 dump_stack_lvl+0x2d/0x90
 __ubsan_handle_out_of_bounds+0xe7/0x140
 ? timerqueue_add+0x98/0xb0
 ieee80211_prep_hw_scan+0x2db/0x480 [mac80211]
 ? __kmalloc+0xe1/0x470
 __ieee80211_start_scan+0x541/0x760 [mac80211]
 rdev_scan+0x1f/0xe0 [cfg80211]
 nl80211_trigger_scan+0x9b6/0xae0 [cfg80211]
 ...&lt;the rest is not too useful...&gt;

Since '__ieee80211_start_scan()' leaves 'hw_scan_req-&gt;req.n_channels'
uninitialized, actual boundaries of 'hw_scan_req-&gt;req.channels' can't
be checked in 'ieee80211_prep_hw_scan()'. Although an initialization
of 'hw_scan_req-&gt;req.n_channels' introduces some confusion around
allocated vs. used VLA members, this shouldn't be a problem since
everything is correctly adjusted soon in 'ieee80211_prep_hw_scan()'.

Cleanup 'kmalloc()' math in '__ieee80211_start_scan()' by using the
convenient 'struct_size()' as well.

Signed-off-by: Dmitry Antipov &lt;dmantipov@yandex.ru&gt;
Link: https://msgid.link/20240517153332.18271-2-dmantipov@yandex.ru
[improve (imho) indentation a bit]
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: correctly parse Spatial Reuse Parameter Set element</title>
<updated>2024-05-29T13:35:12+00:00</updated>
<author>
<name>Lingbo Kong</name>
<email>quic_lingbok@quicinc.com</email>
</author>
<published>2024-05-16T02:18:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=a26d8dc5227f449a54518a8b40733a54c6600a8b'/>
<id>a26d8dc5227f449a54518a8b40733a54c6600a8b</id>
<content type='text'>
Currently, the way of parsing Spatial Reuse Parameter Set element is
incorrect and some members of struct ieee80211_he_obss_pd are not assigned.

To address this issue, it must be parsed in the order of the elements of
Spatial Reuse Parameter Set defined in the IEEE Std 802.11ax specification.

The diagram of the Spatial Reuse Parameter Set element (IEEE Std 802.11ax
-2021-9.4.2.252).

-------------------------------------------------------------------------
|       |      |         |       |Non-SRG|  SRG  | SRG   | SRG  | SRG   |
|Element|Length| Element |  SR   |OBSS PD|OBSS PD|OBSS PD| BSS  |Partial|
|   ID  |      |   ID    |Control|  Max  |  Min  | Max   |Color | BSSID |
|       |      |Extension|       | Offset| Offset|Offset |Bitmap|Bitmap |
-------------------------------------------------------------------------

Fixes: 1ced169cc1c2 ("mac80211: allow setting spatial reuse parameters from bss_conf")
Signed-off-by: Lingbo Kong &lt;quic_lingbok@quicinc.com&gt;
Link: https://msgid.link/20240516021854.5682-3-quic_lingbok@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, the way of parsing Spatial Reuse Parameter Set element is
incorrect and some members of struct ieee80211_he_obss_pd are not assigned.

To address this issue, it must be parsed in the order of the elements of
Spatial Reuse Parameter Set defined in the IEEE Std 802.11ax specification.

The diagram of the Spatial Reuse Parameter Set element (IEEE Std 802.11ax
-2021-9.4.2.252).

-------------------------------------------------------------------------
|       |      |         |       |Non-SRG|  SRG  | SRG   | SRG  | SRG   |
|Element|Length| Element |  SR   |OBSS PD|OBSS PD|OBSS PD| BSS  |Partial|
|   ID  |      |   ID    |Control|  Max  |  Min  | Max   |Color | BSSID |
|       |      |Extension|       | Offset| Offset|Offset |Bitmap|Bitmap |
-------------------------------------------------------------------------

Fixes: 1ced169cc1c2 ("mac80211: allow setting spatial reuse parameters from bss_conf")
Signed-off-by: Lingbo Kong &lt;quic_lingbok@quicinc.com&gt;
Link: https://msgid.link/20240516021854.5682-3-quic_lingbok@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: fix Spatial Reuse element size check</title>
<updated>2024-05-29T13:34:46+00:00</updated>
<author>
<name>Lingbo Kong</name>
<email>quic_lingbok@quicinc.com</email>
</author>
<published>2024-05-16T02:18:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=0c2fd18f7ec552796179c14f13a0e06942f09d16'/>
<id>0c2fd18f7ec552796179c14f13a0e06942f09d16</id>
<content type='text'>
Currently, the way to check the size of Spatial Reuse IE data in the
ieee80211_parse_extension_element() is incorrect.

This is because the len variable in the ieee80211_parse_extension_element()
function is equal to the size of Spatial Reuse IE data minus one and the
value of returned by the ieee80211_he_spr_size() function is equal to
the length of Spatial Reuse IE data. So the result of the
len &gt;= ieee80211_he_spr_size(data) statement always false.

To address this issue and make it consistent with the logic used elsewhere
with ieee80211_he_oper_size(), change the
"len &gt;= ieee80211_he_spr_size(data)" to
“len &gt;= ieee80211_he_spr_size(data) - 1”.

Fixes: 9d0480a7c05b ("wifi: mac80211: move element parsing to a new file")
Signed-off-by: Lingbo Kong &lt;quic_lingbok@quicinc.com&gt;
Link: https://msgid.link/20240516021854.5682-2-quic_lingbok@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, the way to check the size of Spatial Reuse IE data in the
ieee80211_parse_extension_element() is incorrect.

This is because the len variable in the ieee80211_parse_extension_element()
function is equal to the size of Spatial Reuse IE data minus one and the
value of returned by the ieee80211_he_spr_size() function is equal to
the length of Spatial Reuse IE data. So the result of the
len &gt;= ieee80211_he_spr_size(data) statement always false.

To address this issue and make it consistent with the logic used elsewhere
with ieee80211_he_oper_size(), change the
"len &gt;= ieee80211_he_spr_size(data)" to
“len &gt;= ieee80211_he_spr_size(data) - 1”.

Fixes: 9d0480a7c05b ("wifi: mac80211: move element parsing to a new file")
Signed-off-by: Lingbo Kong &lt;quic_lingbok@quicinc.com&gt;
Link: https://msgid.link/20240516021854.5682-2-quic_lingbok@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: pass proper link id for channel switch started notification</title>
<updated>2024-05-29T13:25:36+00:00</updated>
<author>
<name>Aditya Kumar Singh</name>
<email>quic_adisi@quicinc.com</email>
</author>
<published>2024-05-09T03:25:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=8ecc4d7a7cd3e9704b63b8e4f6cd8b6b7314210f'/>
<id>8ecc4d7a7cd3e9704b63b8e4f6cd8b6b7314210f</id>
<content type='text'>
Original changes[1] posted is having proper changes. However, at the same
time, there was chandef puncturing changes which had a conflict with this.
While applying, two errors crept in -
   a) Whitespace error.
   b) Link ID being passed to channel switch started notifier function is
      0. However proper link ID is present in the function.

Fix these now.

[1] https://lore.kernel.org/all/20240130140918.1172387-5-quic_adisi@quicinc.com/

Fixes: 1a96bb4e8a79 ("wifi: mac80211: start and finalize channel switch on link basis")
Signed-off-by: Aditya Kumar Singh &lt;quic_adisi@quicinc.com&gt;
Link: https://msgid.link/20240509032555.263933-1-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Original changes[1] posted is having proper changes. However, at the same
time, there was chandef puncturing changes which had a conflict with this.
While applying, two errors crept in -
   a) Whitespace error.
   b) Link ID being passed to channel switch started notifier function is
      0. However proper link ID is present in the function.

Fix these now.

[1] https://lore.kernel.org/all/20240130140918.1172387-5-quic_adisi@quicinc.com/

Fixes: 1a96bb4e8a79 ("wifi: mac80211: start and finalize channel switch on link basis")
Signed-off-by: Aditya Kumar Singh &lt;quic_adisi@quicinc.com&gt;
Link: https://msgid.link/20240509032555.263933-1-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: handle tasklet frames before stopping</title>
<updated>2024-05-29T13:25:10+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2024-05-15T11:53:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=177c6ae9725d783f9e96f02593ce8fb2639be22f'/>
<id>177c6ae9725d783f9e96f02593ce8fb2639be22f</id>
<content type='text'>
The code itself doesn't want to handle frames from the driver
if it's already stopped, but if the tasklet was queued before
and runs after the stop, then all bets are off. Flush queues
before actually stopping, RX should be off at this point since
all the interfaces are removed already, etc.

Reported-by: syzbot+8830db5d3593b5546d2e@syzkaller.appspotmail.com
Link: https://msgid.link/20240515135318.b05f11385c9a.I41c1b33a2e1814c3a7ef352cd7f2951b91785617@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The code itself doesn't want to handle frames from the driver
if it's already stopped, but if the tasklet was queued before
and runs after the stop, then all bets are off. Flush queues
before actually stopping, RX should be off at this point since
all the interfaces are removed already, etc.

Reported-by: syzbot+8830db5d3593b5546d2e@syzkaller.appspotmail.com
Link: https://msgid.link/20240515135318.b05f11385c9a.I41c1b33a2e1814c3a7ef352cd7f2951b91785617@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: apply mcast rate only if interface is up</title>
<updated>2024-05-29T13:24:52+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2024-05-15T11:34:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=02c665f048a439c0d58cc45334c94634bd7c18e6'/>
<id>02c665f048a439c0d58cc45334c94634bd7c18e6</id>
<content type='text'>
If the interface isn't enabled, don't apply multicast
rate changes immediately.

Reported-by: syzbot+de87c09cc7b964ea2e23@syzkaller.appspotmail.com
Link: https://msgid.link/20240515133410.d6cffe5756cc.I47b624a317e62bdb4609ff7fa79403c0c444d32d@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If the interface isn't enabled, don't apply multicast
rate changes immediately.

Reported-by: syzbot+de87c09cc7b964ea2e23@syzkaller.appspotmail.com
Link: https://msgid.link/20240515133410.d6cffe5756cc.I47b624a317e62bdb4609ff7fa79403c0c444d32d@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: Fix deadlock in ieee80211_sta_ps_deliver_wakeup()</title>
<updated>2024-05-29T13:19:55+00:00</updated>
<author>
<name>Remi Pommarel</name>
<email>repk@triplefau.lt</email>
</author>
<published>2024-05-29T06:57:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=44c06bbde6443de206b30f513100b5670b23fc5e'/>
<id>44c06bbde6443de206b30f513100b5670b23fc5e</id>
<content type='text'>
The ieee80211_sta_ps_deliver_wakeup() function takes sta-&gt;ps_lock to
synchronizes with ieee80211_tx_h_unicast_ps_buf() which is called from
softirq context. However using only spin_lock() to get sta-&gt;ps_lock in
ieee80211_sta_ps_deliver_wakeup() does not prevent softirq to execute
on this same CPU, to run ieee80211_tx_h_unicast_ps_buf() and try to
take this same lock ending in deadlock. Below is an example of rcu stall
that arises in such situation.

 rcu: INFO: rcu_sched self-detected stall on CPU
 rcu:    2-....: (42413413 ticks this GP) idle=b154/1/0x4000000000000000 softirq=1763/1765 fqs=21206996
 rcu:    (t=42586894 jiffies g=2057 q=362405 ncpus=4)
 CPU: 2 PID: 719 Comm: wpa_supplicant Tainted: G        W          6.4.0-02158-g1b062f552873 #742
 Hardware name: RPT (r1) (DT)
 pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : queued_spin_lock_slowpath+0x58/0x2d0
 lr : invoke_tx_handlers_early+0x5b4/0x5c0
 sp : ffff00001ef64660
 x29: ffff00001ef64660 x28: ffff000009bc1070 x27: ffff000009bc0ad8
 x26: ffff000009bc0900 x25: ffff00001ef647a8 x24: 0000000000000000
 x23: ffff000009bc0900 x22: ffff000009bc0900 x21: ffff00000ac0e000
 x20: ffff00000a279e00 x19: ffff00001ef646e8 x18: 0000000000000000
 x17: ffff800016468000 x16: ffff00001ef608c0 x15: 0010533c93f64f80
 x14: 0010395c9faa3946 x13: 0000000000000000 x12: 00000000fa83b2da
 x11: 000000012edeceea x10: ffff0000010fbe00 x9 : 0000000000895440
 x8 : 000000000010533c x7 : ffff00000ad8b740 x6 : ffff00000c350880
 x5 : 0000000000000007 x4 : 0000000000000001 x3 : 0000000000000000
 x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffff00000ac0e0e8
 Call trace:
  queued_spin_lock_slowpath+0x58/0x2d0
  ieee80211_tx+0x80/0x12c
  ieee80211_tx_pending+0x110/0x278
  tasklet_action_common.constprop.0+0x10c/0x144
  tasklet_action+0x20/0x28
  _stext+0x11c/0x284
  ____do_softirq+0xc/0x14
  call_on_irq_stack+0x24/0x34
  do_softirq_own_stack+0x18/0x20
  do_softirq+0x74/0x7c
  __local_bh_enable_ip+0xa0/0xa4
  _ieee80211_wake_txqs+0x3b0/0x4b8
  __ieee80211_wake_queue+0x12c/0x168
  ieee80211_add_pending_skbs+0xec/0x138
  ieee80211_sta_ps_deliver_wakeup+0x2a4/0x480
  ieee80211_mps_sta_status_update.part.0+0xd8/0x11c
  ieee80211_mps_sta_status_update+0x18/0x24
  sta_apply_parameters+0x3bc/0x4c0
  ieee80211_change_station+0x1b8/0x2dc
  nl80211_set_station+0x444/0x49c
  genl_family_rcv_msg_doit.isra.0+0xa4/0xfc
  genl_rcv_msg+0x1b0/0x244
  netlink_rcv_skb+0x38/0x10c
  genl_rcv+0x34/0x48
  netlink_unicast+0x254/0x2bc
  netlink_sendmsg+0x190/0x3b4
  ____sys_sendmsg+0x1e8/0x218
  ___sys_sendmsg+0x68/0x8c
  __sys_sendmsg+0x44/0x84
  __arm64_sys_sendmsg+0x20/0x28
  do_el0_svc+0x6c/0xe8
  el0_svc+0x14/0x48
  el0t_64_sync_handler+0xb0/0xb4
  el0t_64_sync+0x14c/0x150

Using spin_lock_bh()/spin_unlock_bh() instead prevents softirq to raise
on the same CPU that is holding the lock.

Fixes: 1d147bfa6429 ("mac80211: fix AP powersave TX vs. wakeup race")
Signed-off-by: Remi Pommarel &lt;repk@triplefau.lt&gt;
Link: https://msgid.link/8e36fe07d0fbc146f89196cd47a53c8a0afe84aa.1716910344.git.repk@triplefau.lt
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The ieee80211_sta_ps_deliver_wakeup() function takes sta-&gt;ps_lock to
synchronizes with ieee80211_tx_h_unicast_ps_buf() which is called from
softirq context. However using only spin_lock() to get sta-&gt;ps_lock in
ieee80211_sta_ps_deliver_wakeup() does not prevent softirq to execute
on this same CPU, to run ieee80211_tx_h_unicast_ps_buf() and try to
take this same lock ending in deadlock. Below is an example of rcu stall
that arises in such situation.

 rcu: INFO: rcu_sched self-detected stall on CPU
 rcu:    2-....: (42413413 ticks this GP) idle=b154/1/0x4000000000000000 softirq=1763/1765 fqs=21206996
 rcu:    (t=42586894 jiffies g=2057 q=362405 ncpus=4)
 CPU: 2 PID: 719 Comm: wpa_supplicant Tainted: G        W          6.4.0-02158-g1b062f552873 #742
 Hardware name: RPT (r1) (DT)
 pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : queued_spin_lock_slowpath+0x58/0x2d0
 lr : invoke_tx_handlers_early+0x5b4/0x5c0
 sp : ffff00001ef64660
 x29: ffff00001ef64660 x28: ffff000009bc1070 x27: ffff000009bc0ad8
 x26: ffff000009bc0900 x25: ffff00001ef647a8 x24: 0000000000000000
 x23: ffff000009bc0900 x22: ffff000009bc0900 x21: ffff00000ac0e000
 x20: ffff00000a279e00 x19: ffff00001ef646e8 x18: 0000000000000000
 x17: ffff800016468000 x16: ffff00001ef608c0 x15: 0010533c93f64f80
 x14: 0010395c9faa3946 x13: 0000000000000000 x12: 00000000fa83b2da
 x11: 000000012edeceea x10: ffff0000010fbe00 x9 : 0000000000895440
 x8 : 000000000010533c x7 : ffff00000ad8b740 x6 : ffff00000c350880
 x5 : 0000000000000007 x4 : 0000000000000001 x3 : 0000000000000000
 x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffff00000ac0e0e8
 Call trace:
  queued_spin_lock_slowpath+0x58/0x2d0
  ieee80211_tx+0x80/0x12c
  ieee80211_tx_pending+0x110/0x278
  tasklet_action_common.constprop.0+0x10c/0x144
  tasklet_action+0x20/0x28
  _stext+0x11c/0x284
  ____do_softirq+0xc/0x14
  call_on_irq_stack+0x24/0x34
  do_softirq_own_stack+0x18/0x20
  do_softirq+0x74/0x7c
  __local_bh_enable_ip+0xa0/0xa4
  _ieee80211_wake_txqs+0x3b0/0x4b8
  __ieee80211_wake_queue+0x12c/0x168
  ieee80211_add_pending_skbs+0xec/0x138
  ieee80211_sta_ps_deliver_wakeup+0x2a4/0x480
  ieee80211_mps_sta_status_update.part.0+0xd8/0x11c
  ieee80211_mps_sta_status_update+0x18/0x24
  sta_apply_parameters+0x3bc/0x4c0
  ieee80211_change_station+0x1b8/0x2dc
  nl80211_set_station+0x444/0x49c
  genl_family_rcv_msg_doit.isra.0+0xa4/0xfc
  genl_rcv_msg+0x1b0/0x244
  netlink_rcv_skb+0x38/0x10c
  genl_rcv+0x34/0x48
  netlink_unicast+0x254/0x2bc
  netlink_sendmsg+0x190/0x3b4
  ____sys_sendmsg+0x1e8/0x218
  ___sys_sendmsg+0x68/0x8c
  __sys_sendmsg+0x44/0x84
  __arm64_sys_sendmsg+0x20/0x28
  do_el0_svc+0x6c/0xe8
  el0_svc+0x14/0x48
  el0t_64_sync_handler+0xb0/0xb4
  el0t_64_sync+0x14c/0x150

Using spin_lock_bh()/spin_unlock_bh() instead prevents softirq to raise
on the same CPU that is holding the lock.

Fixes: 1d147bfa6429 ("mac80211: fix AP powersave TX vs. wakeup race")
Signed-off-by: Remi Pommarel &lt;repk@triplefau.lt&gt;
Link: https://msgid.link/8e36fe07d0fbc146f89196cd47a53c8a0afe84aa.1716910344.git.repk@triplefau.lt
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
