<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers, branch v6.6.13</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>coresight: etm4x: Fix width of CCITMIN field</title>
<updated>2024-01-20T10:51:49+00:00</updated>
<author>
<name>James Clark</name>
<email>james.clark@arm.com</email>
</author>
<published>2023-11-01T11:52:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=09f222d40fae087a3bc5b0990790cb9622e9a0a0'/>
<id>09f222d40fae087a3bc5b0990790cb9622e9a0a0</id>
<content type='text'>
commit cc0271a339cc70cae914c3ec20edc2a8058407da upstream.

CCITMIN is a 12 bit field and doesn't fit in a u8, so extend it to u16.
This probably wasn't an issue previously because values higher than 255
never occurred.

But since commit 4aff040bcc8d ("coresight: etm: Override TRCIDR3.CCITMIN
on errata affected cpus"), a comparison with 256 was done to enable the
errata, generating the following W=1 build error:

  coresight-etm4x-core.c:1188:24: error: result of comparison of
  constant 256 with expression of type 'u8' (aka 'unsigned char') is
  always false [-Werror,-Wtautological-constant-out-of-range-compare]

   if (drvdata-&gt;ccitmin == 256)

Cc: stable@vger.kernel.org
Fixes: 2e1cdfe184b5 ("coresight-etm4x: Adding CoreSight ETM4x driver")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202310302043.as36UFED-lkp@intel.com/
Reviewed-by: Mike Leach &lt;mike.leach@linaro.org&gt;
Signed-off-by: James Clark &lt;james.clark@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Link: https://lore.kernel.org/r/20231101115206.70810-1-james.clark@arm.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit cc0271a339cc70cae914c3ec20edc2a8058407da upstream.

CCITMIN is a 12 bit field and doesn't fit in a u8, so extend it to u16.
This probably wasn't an issue previously because values higher than 255
never occurred.

But since commit 4aff040bcc8d ("coresight: etm: Override TRCIDR3.CCITMIN
on errata affected cpus"), a comparison with 256 was done to enable the
errata, generating the following W=1 build error:

  coresight-etm4x-core.c:1188:24: error: result of comparison of
  constant 256 with expression of type 'u8' (aka 'unsigned char') is
  always false [-Werror,-Wtautological-constant-out-of-range-compare]

   if (drvdata-&gt;ccitmin == 256)

Cc: stable@vger.kernel.org
Fixes: 2e1cdfe184b5 ("coresight-etm4x: Adding CoreSight ETM4x driver")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202310302043.as36UFED-lkp@intel.com/
Reviewed-by: Mike Leach &lt;mike.leach@linaro.org&gt;
Signed-off-by: James Clark &lt;james.clark@arm.com&gt;
Signed-off-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Link: https://lore.kernel.org/r/20231101115206.70810-1-james.clark@arm.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Add ACS quirk for more Zhaoxin Root Ports</title>
<updated>2024-01-20T10:51:49+00:00</updated>
<author>
<name>LeoLiuoc</name>
<email>LeoLiu-oc@zhaoxin.com</email>
</author>
<published>2023-12-11T09:15:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=d6d19c3d1792aaf7e04ebecb79e81bfdc6baab54'/>
<id>d6d19c3d1792aaf7e04ebecb79e81bfdc6baab54</id>
<content type='text'>
commit e367e3c765f5477b2e79da0f1399aed49e2d1e37 upstream.

Add more Root Port Device IDs to pci_quirk_zhaoxin_pcie_ports_acs() for
some new Zhaoxin platforms.

Fixes: 299bd044a6f3 ("PCI: Add ACS quirk for Zhaoxin Root/Downstream Ports")
Link: https://lore.kernel.org/r/20231211091543.735903-1-LeoLiu-oc@zhaoxin.com
Signed-off-by: LeoLiuoc &lt;LeoLiu-oc@zhaoxin.com&gt;
[bhelgaas: update subject, drop changelog, add Fixes, add stable tag, fix
whitespace, wrap code comment]
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;	# 5.7
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e367e3c765f5477b2e79da0f1399aed49e2d1e37 upstream.

Add more Root Port Device IDs to pci_quirk_zhaoxin_pcie_ports_acs() for
some new Zhaoxin platforms.

Fixes: 299bd044a6f3 ("PCI: Add ACS quirk for Zhaoxin Root/Downstream Ports")
Link: https://lore.kernel.org/r/20231211091543.735903-1-LeoLiu-oc@zhaoxin.com
Signed-off-by: LeoLiuoc &lt;LeoLiu-oc@zhaoxin.com&gt;
[bhelgaas: update subject, drop changelog, add Fixes, add stable tag, fix
whitespace, wrap code comment]
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;	# 5.7
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>leds: ledtrig-tty: Free allocated ttyname buffer on deactivate</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Florian Eckert</name>
<email>fe@dev.tdt.de</email>
</author>
<published>2023-11-27T08:16:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7db7504a3e4134b403dbc94fba807529b64ae55a'/>
<id>7db7504a3e4134b403dbc94fba807529b64ae55a</id>
<content type='text'>
commit 25054b232681c286fca9c678854f56494d1352cc upstream.

The ttyname buffer for the ledtrig_tty_data struct is allocated in the
sysfs ttyname_store() function. This buffer must be released on trigger
deactivation. This was missing and is thus a memory leak.

While we are at it, the TTY handler in the ledtrig_tty_data struct should
also be returned in case of the trigger deactivation call.

Cc: stable@vger.kernel.org
Fixes: fd4a641ac88f ("leds: trigger: implement a tty trigger")
Signed-off-by: Florian Eckert &lt;fe@dev.tdt.de&gt;
Reviewed-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20231127081621.774866-1-fe@dev.tdt.de
Signed-off-by: Lee Jones &lt;lee@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 25054b232681c286fca9c678854f56494d1352cc upstream.

The ttyname buffer for the ledtrig_tty_data struct is allocated in the
sysfs ttyname_store() function. This buffer must be released on trigger
deactivation. This was missing and is thus a memory leak.

While we are at it, the TTY handler in the ledtrig_tty_data struct should
also be returned in case of the trigger deactivation call.

Cc: stable@vger.kernel.org
Fixes: fd4a641ac88f ("leds: trigger: implement a tty trigger")
Signed-off-by: Florian Eckert &lt;fe@dev.tdt.de&gt;
Reviewed-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20231127081621.774866-1-fe@dev.tdt.de
Signed-off-by: Lee Jones &lt;lee@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>parport: parport_serial: Add Brainboxes device IDs and geometry</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Cameron Williams</name>
<email>cang1@live.co.uk</email>
</author>
<published>2023-11-02T21:07:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=12786872b26a81fadd3895368d9289a2c7bd9129'/>
<id>12786872b26a81fadd3895368d9289a2c7bd9129</id>
<content type='text'>
commit 6aa1fc5a8085bbc01687aa708dcf2dbe637a5ee3 upstream.

Add device IDs for the Brainboxes UC-203, UC-257, UC-414, UC-475,
IS-300/IS-500 and PX-263/PX-295 and define the relevant "geometry"
for the cards.
This patch requires part 1 of this series.

Cc:  &lt;stable@vger.kernel.org&gt;
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Acked-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Link: https://lore.kernel.org/r/AS4PR02MB7903A4094564BE28F1F926A6C4A6A@AS4PR02MB7903.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6aa1fc5a8085bbc01687aa708dcf2dbe637a5ee3 upstream.

Add device IDs for the Brainboxes UC-203, UC-257, UC-414, UC-475,
IS-300/IS-500 and PX-263/PX-295 and define the relevant "geometry"
for the cards.
This patch requires part 1 of this series.

Cc:  &lt;stable@vger.kernel.org&gt;
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Acked-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Link: https://lore.kernel.org/r/AS4PR02MB7903A4094564BE28F1F926A6C4A6A@AS4PR02MB7903.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>parport: parport_serial: Add Brainboxes BAR details</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Cameron Williams</name>
<email>cang1@live.co.uk</email>
</author>
<published>2023-11-02T21:07:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=03427e7f2a56df2049a4ea46aed5656cd7d88d21'/>
<id>03427e7f2a56df2049a4ea46aed5656cd7d88d21</id>
<content type='text'>
commit 65fde134b0a4ffe838729f9ee11b459a2f6f2815 upstream.

Add BAR/enum entries for Brainboxes serial/parallel cards.

Cc:  &lt;stable@vger.kernel.org&gt;
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Acked-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Link: https://lore.kernel.org/r/AS4PR02MB79035155C2D5C3333AE6FA52C4A6A@AS4PR02MB7903.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 65fde134b0a4ffe838729f9ee11b459a2f6f2815 upstream.

Add BAR/enum entries for Brainboxes serial/parallel cards.

Cc:  &lt;stable@vger.kernel.org&gt;
Signed-off-by: Cameron Williams &lt;cang1@live.co.uk&gt;
Acked-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Link: https://lore.kernel.org/r/AS4PR02MB79035155C2D5C3333AE6FA52C4A6A@AS4PR02MB7903.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>uio: Fix use-after-free in uio_open</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Guanghui Feng</name>
<email>guanghuifeng@linux.alibaba.com</email>
</author>
<published>2023-12-21T09:57:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=35f102607054faafe78d2a6994b18d5d9d6e92ad'/>
<id>35f102607054faafe78d2a6994b18d5d9d6e92ad</id>
<content type='text'>
commit 0c9ae0b8605078eafc3bea053cc78791e97ba2e2 upstream.

core-1				core-2
-------------------------------------------------------
uio_unregister_device		uio_open
				idev = idr_find()
device_unregister(&amp;idev-&gt;dev)
put_device(&amp;idev-&gt;dev)
uio_device_release
				get_device(&amp;idev-&gt;dev)
kfree(idev)
uio_free_minor(minor)
				uio_release
				put_device(&amp;idev-&gt;dev)
				kfree(idev)
-------------------------------------------------------

In the core-1 uio_unregister_device(), the device_unregister will kfree
idev when the idev-&gt;dev kobject ref is 1. But after core-1
device_unregister, put_device and before doing kfree, the core-2 may
get_device. Then:
1. After core-1 kfree idev, the core-2 will do use-after-free for idev.
2. When core-2 do uio_release and put_device, the idev will be double
   freed.

To address this issue, we can get idev atomic &amp; inc idev reference with
minor_lock.

Fixes: 57c5f4df0a5a ("uio: fix crash after the device is unregistered")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Guanghui Feng &lt;guanghuifeng@linux.alibaba.com&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/1703152663-59949-1-git-send-email-guanghuifeng@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0c9ae0b8605078eafc3bea053cc78791e97ba2e2 upstream.

core-1				core-2
-------------------------------------------------------
uio_unregister_device		uio_open
				idev = idr_find()
device_unregister(&amp;idev-&gt;dev)
put_device(&amp;idev-&gt;dev)
uio_device_release
				get_device(&amp;idev-&gt;dev)
kfree(idev)
uio_free_minor(minor)
				uio_release
				put_device(&amp;idev-&gt;dev)
				kfree(idev)
-------------------------------------------------------

In the core-1 uio_unregister_device(), the device_unregister will kfree
idev when the idev-&gt;dev kobject ref is 1. But after core-1
device_unregister, put_device and before doing kfree, the core-2 may
get_device. Then:
1. After core-1 kfree idev, the core-2 will do use-after-free for idev.
2. When core-2 do uio_release and put_device, the idev will be double
   freed.

To address this issue, we can get idev atomic &amp; inc idev reference with
minor_lock.

Fixes: 57c5f4df0a5a ("uio: fix crash after the device is unregistered")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Guanghui Feng &lt;guanghuifeng@linux.alibaba.com&gt;
Reviewed-by: Baolin Wang &lt;baolin.wang@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/1703152663-59949-1-git-send-email-guanghuifeng@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: fix comment on binder_alloc_new_buf() return value</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2023-12-01T17:21:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f4d6dbaa437617d41c2c5c3b746cd9a0c42f414b'/>
<id>f4d6dbaa437617d41c2c5c3b746cd9a0c42f414b</id>
<content type='text'>
commit e1090371e02b601cbfcea175c2a6cc7c955fa830 upstream.

Update the comments of binder_alloc_new_buf() to reflect that the return
value of the function is now ERR_PTR(-errno) on failure.

No functional changes in this patch.

Cc: stable@vger.kernel.org
Fixes: 57ada2fb2250 ("binder: add log information for binder transaction failures")
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-8-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e1090371e02b601cbfcea175c2a6cc7c955fa830 upstream.

Update the comments of binder_alloc_new_buf() to reflect that the return
value of the function is now ERR_PTR(-errno) on failure.

No functional changes in this patch.

Cc: stable@vger.kernel.org
Fixes: 57ada2fb2250 ("binder: add log information for binder transaction failures")
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-8-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: fix trivial typo of binder_free_buf_locked()</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2023-12-01T17:21:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=8040d704adce53d8ad5b37937caa4dc5b9edeb45'/>
<id>8040d704adce53d8ad5b37937caa4dc5b9edeb45</id>
<content type='text'>
commit 122a3c1cb0ff304c2b8934584fcfea4edb2fe5e3 upstream.

Fix minor misspelling of the function in the comment section.

No functional changes in this patch.

Cc: stable@vger.kernel.org
Fixes: 0f966cba95c7 ("binder: add flag to clear buffer on txn complete")
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-7-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 122a3c1cb0ff304c2b8934584fcfea4edb2fe5e3 upstream.

Fix minor misspelling of the function in the comment section.

No functional changes in this patch.

Cc: stable@vger.kernel.org
Fixes: 0f966cba95c7 ("binder: add flag to clear buffer on txn complete")
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-7-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: fix use-after-free in shinker's callback</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2023-12-01T17:21:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=a49087ab93508b60d9b8add91707a22dda832869'/>
<id>a49087ab93508b60d9b8add91707a22dda832869</id>
<content type='text'>
commit 3f489c2067c5824528212b0fc18b28d51332d906 upstream.

The mmap read lock is used during the shrinker's callback, which means
that using alloc-&gt;vma pointer isn't safe as it can race with munmap().
As of commit dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in
munmap") the mmap lock is downgraded after the vma has been isolated.

I was able to reproduce this issue by manually adding some delays and
triggering page reclaiming through the shrinker's debug sysfs. The
following KASAN report confirms the UAF:

  ==================================================================
  BUG: KASAN: slab-use-after-free in zap_page_range_single+0x470/0x4b8
  Read of size 8 at addr ffff356ed50e50f0 by task bash/478

  CPU: 1 PID: 478 Comm: bash Not tainted 6.6.0-rc5-00055-g1c8b86a3799f-dirty #70
  Hardware name: linux,dummy-virt (DT)
  Call trace:
   zap_page_range_single+0x470/0x4b8
   binder_alloc_free_page+0x608/0xadc
   __list_lru_walk_one+0x130/0x3b0
   list_lru_walk_node+0xc4/0x22c
   binder_shrink_scan+0x108/0x1dc
   shrinker_debugfs_scan_write+0x2b4/0x500
   full_proxy_write+0xd4/0x140
   vfs_write+0x1ac/0x758
   ksys_write+0xf0/0x1dc
   __arm64_sys_write+0x6c/0x9c

  Allocated by task 492:
   kmem_cache_alloc+0x130/0x368
   vm_area_alloc+0x2c/0x190
   mmap_region+0x258/0x18bc
   do_mmap+0x694/0xa60
   vm_mmap_pgoff+0x170/0x29c
   ksys_mmap_pgoff+0x290/0x3a0
   __arm64_sys_mmap+0xcc/0x144

  Freed by task 491:
   kmem_cache_free+0x17c/0x3c8
   vm_area_free_rcu_cb+0x74/0x98
   rcu_core+0xa38/0x26d4
   rcu_core_si+0x10/0x1c
   __do_softirq+0x2fc/0xd24

  Last potentially related work creation:
   __call_rcu_common.constprop.0+0x6c/0xba0
   call_rcu+0x10/0x1c
   vm_area_free+0x18/0x24
   remove_vma+0xe4/0x118
   do_vmi_align_munmap.isra.0+0x718/0xb5c
   do_vmi_munmap+0xdc/0x1fc
   __vm_munmap+0x10c/0x278
   __arm64_sys_munmap+0x58/0x7c

Fix this issue by performing instead a vma_lookup() which will fail to
find the vma that was isolated before the mmap lock downgrade. Note that
this option has better performance than upgrading to a mmap write lock
which would increase contention. Plus, mmap_write_trylock() has been
recently removed anyway.

Fixes: dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap")
Cc: stable@vger.kernel.org
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3f489c2067c5824528212b0fc18b28d51332d906 upstream.

The mmap read lock is used during the shrinker's callback, which means
that using alloc-&gt;vma pointer isn't safe as it can race with munmap().
As of commit dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in
munmap") the mmap lock is downgraded after the vma has been isolated.

I was able to reproduce this issue by manually adding some delays and
triggering page reclaiming through the shrinker's debug sysfs. The
following KASAN report confirms the UAF:

  ==================================================================
  BUG: KASAN: slab-use-after-free in zap_page_range_single+0x470/0x4b8
  Read of size 8 at addr ffff356ed50e50f0 by task bash/478

  CPU: 1 PID: 478 Comm: bash Not tainted 6.6.0-rc5-00055-g1c8b86a3799f-dirty #70
  Hardware name: linux,dummy-virt (DT)
  Call trace:
   zap_page_range_single+0x470/0x4b8
   binder_alloc_free_page+0x608/0xadc
   __list_lru_walk_one+0x130/0x3b0
   list_lru_walk_node+0xc4/0x22c
   binder_shrink_scan+0x108/0x1dc
   shrinker_debugfs_scan_write+0x2b4/0x500
   full_proxy_write+0xd4/0x140
   vfs_write+0x1ac/0x758
   ksys_write+0xf0/0x1dc
   __arm64_sys_write+0x6c/0x9c

  Allocated by task 492:
   kmem_cache_alloc+0x130/0x368
   vm_area_alloc+0x2c/0x190
   mmap_region+0x258/0x18bc
   do_mmap+0x694/0xa60
   vm_mmap_pgoff+0x170/0x29c
   ksys_mmap_pgoff+0x290/0x3a0
   __arm64_sys_mmap+0xcc/0x144

  Freed by task 491:
   kmem_cache_free+0x17c/0x3c8
   vm_area_free_rcu_cb+0x74/0x98
   rcu_core+0xa38/0x26d4
   rcu_core_si+0x10/0x1c
   __do_softirq+0x2fc/0xd24

  Last potentially related work creation:
   __call_rcu_common.constprop.0+0x6c/0xba0
   call_rcu+0x10/0x1c
   vm_area_free+0x18/0x24
   remove_vma+0xe4/0x118
   do_vmi_align_munmap.isra.0+0x718/0xb5c
   do_vmi_munmap+0xdc/0x1fc
   __vm_munmap+0x10c/0x278
   __arm64_sys_munmap+0x58/0x7c

Fix this issue by performing instead a vma_lookup() which will fail to
find the vma that was isolated before the mmap lock downgrade. Note that
this option has better performance than upgrading to a mmap write lock
which would increase contention. Plus, mmap_write_trylock() has been
recently removed anyway.

Fixes: dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap")
Cc: stable@vger.kernel.org
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Minchan Kim &lt;minchan@kernel.org&gt;
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>binder: use EPOLLERR from eventpoll.h</title>
<updated>2024-01-20T10:51:48+00:00</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2023-12-01T17:21:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=802c61319ec246b537d7ca36f04af9f8a1a5ee25'/>
<id>802c61319ec246b537d7ca36f04af9f8a1a5ee25</id>
<content type='text'>
commit 6ac061db9c58ca5b9270b1b3940d2464fb3ff183 upstream.

Use EPOLLERR instead of POLLERR to make sure it is cast to the correct
__poll_t type. This fixes the following sparse issue:

  drivers/android/binder.c:5030:24: warning: incorrect type in return expression (different base types)
  drivers/android/binder.c:5030:24:    expected restricted __poll_t
  drivers/android/binder.c:5030:24:    got int

Fixes: f88982679f54 ("binder: check for binder_thread allocation failure in binder_poll()")
Cc: stable@vger.kernel.org
Cc: Eric Biggers &lt;ebiggers@google.com&gt;
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-2-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6ac061db9c58ca5b9270b1b3940d2464fb3ff183 upstream.

Use EPOLLERR instead of POLLERR to make sure it is cast to the correct
__poll_t type. This fixes the following sparse issue:

  drivers/android/binder.c:5030:24: warning: incorrect type in return expression (different base types)
  drivers/android/binder.c:5030:24:    expected restricted __poll_t
  drivers/android/binder.c:5030:24:    got int

Fixes: f88982679f54 ("binder: check for binder_thread allocation failure in binder_poll()")
Cc: stable@vger.kernel.org
Cc: Eric Biggers &lt;ebiggers@google.com&gt;
Reviewed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Link: https://lore.kernel.org/r/20231201172212.1813387-2-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
