<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/bluetooth, branch v7.2.1</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Bluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255</title>
<updated>2026-08-27T12:35:27+00:00</updated>
<author>
<name>Ali Ahmet Memis</name>
<email>ali@iusegentoo.com</email>
</author>
<published>2026-08-06T17:39:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6e1c44878aa3ee7336efeaf01414b030b0a5c273'/>
<id>6e1c44878aa3ee7336efeaf01414b030b0a5c273</id>
<content type='text'>
commit 5d95286b6d6e8f1d304da7522bfa6860fc017e48 upstream.

mgmt_hci_cmd_sync() checks that the message length agrees with params_len
but puts no upper bound on it. params_len is __le16 while the parameter
length in the HCI command header is a u8:

	struct hci_command_hdr {
		__le16	opcode;
		__u8	plen;
	} __packed;

hci_cmd_sync_alloc() assigns one to the other:

	hdr-&gt;plen = plen;

	if (plen)
		skb_put_data(skb, param, plen);

so a params_len of 256 leaves plen at 0 while all 256 bytes are still
appended. The frame handed to the driver then declares no parameters and
carries 256 of them. On a length framed transport such as H:4 the
controller takes the trailing bytes as the start of the next packet.

The mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about
1KB this way. Commit 03f1700b9b4d ("Bluetooth: MGMT: reject malformed
HCI_CMD_SYNC commands") only made params_len agree with the message
length, a value that fits the message but not the header field is still
accepted.

Reject params_len that does not fit the header field.

Fixes: 827af4787e74 ("Bluetooth: MGMT: Add initial implementation of MGMT_OP_HCI_CMD_SYNC")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 5d95286b6d6e8f1d304da7522bfa6860fc017e48 upstream.

mgmt_hci_cmd_sync() checks that the message length agrees with params_len
but puts no upper bound on it. params_len is __le16 while the parameter
length in the HCI command header is a u8:

	struct hci_command_hdr {
		__le16	opcode;
		__u8	plen;
	} __packed;

hci_cmd_sync_alloc() assigns one to the other:

	hdr-&gt;plen = plen;

	if (plen)
		skb_put_data(skb, param, plen);

so a params_len of 256 leaves plen at 0 while all 256 bytes are still
appended. The frame handed to the driver then declares no parameters and
carries 256 of them. On a length framed transport such as H:4 the
controller takes the trailing bytes as the start of the next packet.

The mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about
1KB this way. Commit 03f1700b9b4d ("Bluetooth: MGMT: reject malformed
HCI_CMD_SYNC commands") only made params_len agree with the message
length, a value that fits the message but not the header field is still
accepted.

Reject params_len that does not fit the header field.

Fixes: 827af4787e74 ("Bluetooth: MGMT: Add initial implementation of MGMT_OP_HCI_CMD_SYNC")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: ISO: zero the sockaddr before returning it in getname</title>
<updated>2026-08-27T12:35:27+00:00</updated>
<author>
<name>Ali Ahmet Memis</name>
<email>ali@iusegentoo.com</email>
</author>
<published>2026-08-06T23:06:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=190b719b787eb4ca6c25b12fab224806f9108b06'/>
<id>190b719b787eb4ca6c25b12fab224806f9108b06</id>
<content type='text'>
commit 884cf2cc957da7ac178a0e6c6c69ddfec0481cc8 upstream.

iso_sock_getname() fills a struct sockaddr_iso in place and returns its
size without clearing it first, so bytes it does not write are copied to
user space from the kernel stack. The getsockname(2) and getpeername(2)
paths both run through do_getsockname(), which hands getname() an
uninitialized sockaddr_storage on the stack and copies back up to the
number of bytes getname() returns, so the driver has to initialize every
byte it accounts for.

Two ranges are left uninitialized:

  - struct sockaddr_iso is 10 bytes but only 9 are written (family,
    iso_bdaddr, iso_bdaddr_type), leaking the trailing pad byte on every
    call.

  - for a broadcast peer (BIS_LINK or PA_LINK) the returned length grows
    by sizeof(struct sockaddr_iso_bc), but only bc_sid, bc_num_bis and
    bc_bis are filled; bc_bdaddr and bc_bdaddr_type, the first 7 bytes of
    that structure, are never written.

An unprivileged process can open a BTPROTO_ISO socket and reach the pad
leak with getsockname(); the broadcast leak needs an established BIS/PA
connection. l2cap and rfcomm already memset their sockaddr in getname
for the same reason; do the same here.

Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type")
Fixes: 0a766a0affb5 ("Bluetooth: ISO: Fix getpeername not returning sockaddr_iso_bc fields")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 884cf2cc957da7ac178a0e6c6c69ddfec0481cc8 upstream.

iso_sock_getname() fills a struct sockaddr_iso in place and returns its
size without clearing it first, so bytes it does not write are copied to
user space from the kernel stack. The getsockname(2) and getpeername(2)
paths both run through do_getsockname(), which hands getname() an
uninitialized sockaddr_storage on the stack and copies back up to the
number of bytes getname() returns, so the driver has to initialize every
byte it accounts for.

Two ranges are left uninitialized:

  - struct sockaddr_iso is 10 bytes but only 9 are written (family,
    iso_bdaddr, iso_bdaddr_type), leaking the trailing pad byte on every
    call.

  - for a broadcast peer (BIS_LINK or PA_LINK) the returned length grows
    by sizeof(struct sockaddr_iso_bc), but only bc_sid, bc_num_bis and
    bc_bis are filled; bc_bdaddr and bc_bdaddr_type, the first 7 bytes of
    that structure, are never written.

An unprivileged process can open a BTPROTO_ISO socket and reach the pad
leak with getsockname(); the broadcast leak needs an established BIS/PA
connection. l2cap and rfcomm already memset their sockaddr in getname
for the same reason; do the same here.

Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type")
Fixes: 0a766a0affb5 ("Bluetooth: ISO: Fix getpeername not returning sockaddr_iso_bc fields")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: ISO: do not force BT_LISTEN after a failed BIG sync</title>
<updated>2026-08-27T12:35:26+00:00</updated>
<author>
<name>Ali Ahmet Memis</name>
<email>ali@iusegentoo.com</email>
</author>
<published>2026-08-07T00:59:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9f59f461dcae326663d4387b4aa1186925936f33'/>
<id>9f59f461dcae326663d4387b4aa1186925936f33</id>
<content type='text'>
commit 9838a80096ba472d5e03057136a112631aabae6e upstream.

iso_sock_recvmsg() handles the deferred setup of a broadcast sink by
dropping the socket lock, calling iso_conn_big_sync() and taking the
lock again:

	release_sock(sk);
	iso_conn_big_sync(sk);
	lock_sock(sk);

	sk-&gt;sk_state = BT_LISTEN;

The state is written unconditionally, but iso_conn_big_sync() returns
void and has paths that do nothing at all: hci_get_route() may fail, and
after re-acquiring the socket lock the connection may already be gone,
in which case it bails out without ever issuing an LE BIG Create Sync.

While the lock is dropped the connection can be torn down, for example
when the controller reports HCI_EV_LE_PA_SYNC_LOST:

	hci_le_pa_sync_lost_evt()
	  hci_disconn_cfm() -&gt; iso_disconn_cfm() -&gt; iso_conn_del()
	    iso_chan_del()
	      iso_pi(sk)-&gt;conn = NULL
	      sk-&gt;sk_state = BT_CLOSED
	      sock_set_flag(sk, SOCK_ZAPPED)

iso_conn_big_sync() then finds conn == NULL and returns, but the caller
still overwrites the BT_CLOSED that iso_chan_del() has just set. The
socket ends up marked BT_LISTEN with no connection, so recvmsg() reports
success for a setup that never happened and a later accept() waits for
BIS connections that can never arrive instead of failing.

A concurrent shutdown() reaches the same write by another route:
__iso_sock_close() takes the BT_CONNECT2 PA sync path to
iso_sock_disconn(), which sets BT_DISCONN but leaves conn and
conn-&gt;hcon in place, so iso_conn_big_sync() succeeds and BT_LISTEN is
written over BT_DISCONN. Both the BT_CONNECT2 and the BT_CONNECTED case
write the state the same way.

Let iso_conn_big_sync() report whether the BIG sync was started, and
only move the socket to BT_LISTEN when it was and when the state has not
changed while the lock was dropped, mirroring what the BT_CONNECT case
of the same switch already does with iso_connect_cis(). Both conditions
are needed, the error alone does not cover the shutdown() race.

This corrupts the socket state machine only, it is not a memory safety
issue. KASAN and lockdep stayed quiet in all of the runs below.

Reproduced with an emulated controller over /dev/vhci on a KASAN +
PROVE_LOCKING kernel. A PA sync broadcast sink socket is driven to
BT_CONNECT2 and recvmsg() on it is raced against teardown, with a debug
delay inside the lock-dropped section to widen the window:

 - HCI_EV_LE_PA_SYNC_LOST injected: 64 of 64 rounds left the socket in
   BT_LISTEN with the connection gone, recvmsg() returned 0 and accept()
   on that fd returned EAGAIN, which iso_sock_accept() can only do while
   the socket is BT_LISTEN. With this patch, 0 of 64, recvmsg() returns
   an error and accept() returns EBADFD.

 - shutdown() instead of a controller event: 24 of 32 rounds wedged in
   BT_LISTEN, 0 of 32 with this patch. With only the error check in
   place and a short window, one round still wedged while recvmsg()
   returned 0, which is the case the state re-check covers.

An unraced control round behaves the same before and after: recvmsg()
returns 0, the socket reaches BT_LISTEN and an LE BIG Create Sync is
issued.

Fixes: 7a17308c1788 ("Bluetooth: iso: Fix circular lock in iso_conn_big_sync")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 9838a80096ba472d5e03057136a112631aabae6e upstream.

iso_sock_recvmsg() handles the deferred setup of a broadcast sink by
dropping the socket lock, calling iso_conn_big_sync() and taking the
lock again:

	release_sock(sk);
	iso_conn_big_sync(sk);
	lock_sock(sk);

	sk-&gt;sk_state = BT_LISTEN;

The state is written unconditionally, but iso_conn_big_sync() returns
void and has paths that do nothing at all: hci_get_route() may fail, and
after re-acquiring the socket lock the connection may already be gone,
in which case it bails out without ever issuing an LE BIG Create Sync.

While the lock is dropped the connection can be torn down, for example
when the controller reports HCI_EV_LE_PA_SYNC_LOST:

	hci_le_pa_sync_lost_evt()
	  hci_disconn_cfm() -&gt; iso_disconn_cfm() -&gt; iso_conn_del()
	    iso_chan_del()
	      iso_pi(sk)-&gt;conn = NULL
	      sk-&gt;sk_state = BT_CLOSED
	      sock_set_flag(sk, SOCK_ZAPPED)

iso_conn_big_sync() then finds conn == NULL and returns, but the caller
still overwrites the BT_CLOSED that iso_chan_del() has just set. The
socket ends up marked BT_LISTEN with no connection, so recvmsg() reports
success for a setup that never happened and a later accept() waits for
BIS connections that can never arrive instead of failing.

A concurrent shutdown() reaches the same write by another route:
__iso_sock_close() takes the BT_CONNECT2 PA sync path to
iso_sock_disconn(), which sets BT_DISCONN but leaves conn and
conn-&gt;hcon in place, so iso_conn_big_sync() succeeds and BT_LISTEN is
written over BT_DISCONN. Both the BT_CONNECT2 and the BT_CONNECTED case
write the state the same way.

Let iso_conn_big_sync() report whether the BIG sync was started, and
only move the socket to BT_LISTEN when it was and when the state has not
changed while the lock was dropped, mirroring what the BT_CONNECT case
of the same switch already does with iso_connect_cis(). Both conditions
are needed, the error alone does not cover the shutdown() race.

This corrupts the socket state machine only, it is not a memory safety
issue. KASAN and lockdep stayed quiet in all of the runs below.

Reproduced with an emulated controller over /dev/vhci on a KASAN +
PROVE_LOCKING kernel. A PA sync broadcast sink socket is driven to
BT_CONNECT2 and recvmsg() on it is raced against teardown, with a debug
delay inside the lock-dropped section to widen the window:

 - HCI_EV_LE_PA_SYNC_LOST injected: 64 of 64 rounds left the socket in
   BT_LISTEN with the connection gone, recvmsg() returned 0 and accept()
   on that fd returned EAGAIN, which iso_sock_accept() can only do while
   the socket is BT_LISTEN. With this patch, 0 of 64, recvmsg() returns
   an error and accept() returns EBADFD.

 - shutdown() instead of a controller event: 24 of 32 rounds wedged in
   BT_LISTEN, 0 of 32 with this patch. With only the error check in
   place and a short window, one round still wedged while recvmsg()
   returned 0, which is the case the state re-check covers.

An unraced control round behaves the same before and after: recvmsg()
returns 0, the socket reaches BT_LISTEN and an LE BIG Create Sync is
issued.

Fixes: 7a17308c1788 ("Bluetooth: iso: Fix circular lock in iso_conn_big_sync")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: hci_sync: Fix accept list UAF during suspend</title>
<updated>2026-08-27T12:35:26+00:00</updated>
<author>
<name>Chengfeng Ye</name>
<email>nicoyip.dev@gmail.com</email>
</author>
<published>2026-08-01T07:05:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=29c59212a507804d7616b8abf491d30b4ab8e75f'/>
<id>29c59212a507804d7616b8abf491d30b4ab8e75f</id>
<content type='text'>
commit f57b399c4fa1501b2d5451f52d861ece86bcf3db upstream.

hci_update_event_filter_sync() walks hdev-&gt;accept_list while sending a
synchronous HCI command for each remote-wakeup device.  The suspend path
holds hdev-&gt;req_lock, but accept-list updates are serialized by hdev-&gt;lock.
Consequently, remove_device() can free the current list entry during the
controller wait.

The following interleaving causes the use-after-free:

  hci_update_event_filter_sync()    remove_device()
  fetch accept-list entry
  hci_set_event_filter_sync()
    wait for controller response    hci_dev_lock()
                                    list_del()
                                    kfree()
                                    hci_dev_unlock()
  read the freed list.next

KASAN reported:

  BUG: KASAN: slab-use-after-free in hci_suspend_sync+0x835/0x910
  Read of size 8 at addr ffff88810bec8440 by task kworker/0:1/10
  Workqueue: events vhci_suspend_work
  Call Trace:
   hci_suspend_sync+0x835/0x910
   hci_suspend_dev+0x182/0x450
   process_one_work+0x661/0x1090
   worker_thread+0x45b/0xd10

  Allocated by task 86:
   hci_bdaddr_list_add_with_flags+0x1a8/0x400
   add_device+0x381/0x820
   hci_sock_sendmsg+0x1033/0x1ea0

  Freed by task 91:
   kfree+0x131/0x3c0
   remove_device+0x429/0xb70
   hci_sock_sendmsg+0x1033/0x1ea0

Snapshot the remote-wakeup addresses under hdev-&gt;lock.  Release the lock
before sending HCI commands.  Clear the controller event filter before
building the snapshot, and skip allocation and the second list traversal
when there are no matching entries.  This preserves the original filter
and scan-state updates without retaining an accept-list node across a
controller wait.

Fixes: 182ee45da083 ("Bluetooth: hci_sync: Rework hci_suspend_notifier")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-bluetooth/20260730092331.2069741-1-nicoyip.dev@gmail.com/
Signed-off-by: Chengfeng Ye &lt;nicoyip.dev@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 f57b399c4fa1501b2d5451f52d861ece86bcf3db upstream.

hci_update_event_filter_sync() walks hdev-&gt;accept_list while sending a
synchronous HCI command for each remote-wakeup device.  The suspend path
holds hdev-&gt;req_lock, but accept-list updates are serialized by hdev-&gt;lock.
Consequently, remove_device() can free the current list entry during the
controller wait.

The following interleaving causes the use-after-free:

  hci_update_event_filter_sync()    remove_device()
  fetch accept-list entry
  hci_set_event_filter_sync()
    wait for controller response    hci_dev_lock()
                                    list_del()
                                    kfree()
                                    hci_dev_unlock()
  read the freed list.next

KASAN reported:

  BUG: KASAN: slab-use-after-free in hci_suspend_sync+0x835/0x910
  Read of size 8 at addr ffff88810bec8440 by task kworker/0:1/10
  Workqueue: events vhci_suspend_work
  Call Trace:
   hci_suspend_sync+0x835/0x910
   hci_suspend_dev+0x182/0x450
   process_one_work+0x661/0x1090
   worker_thread+0x45b/0xd10

  Allocated by task 86:
   hci_bdaddr_list_add_with_flags+0x1a8/0x400
   add_device+0x381/0x820
   hci_sock_sendmsg+0x1033/0x1ea0

  Freed by task 91:
   kfree+0x131/0x3c0
   remove_device+0x429/0xb70
   hci_sock_sendmsg+0x1033/0x1ea0

Snapshot the remote-wakeup addresses under hdev-&gt;lock.  Release the lock
before sending HCI commands.  Clear the controller event filter before
building the snapshot, and skip allocation and the second list traversal
when there are no matching entries.  This preserves the original filter
and scan-state updates without retaining an accept-list node across a
controller wait.

Fixes: 182ee45da083 ("Bluetooth: hci_sync: Rework hci_suspend_notifier")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-bluetooth/20260730092331.2069741-1-nicoyip.dev@gmail.com/
Signed-off-by: Chengfeng Ye &lt;nicoyip.dev@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: hci_event: validate LE Set CIG Parameters response</title>
<updated>2026-08-27T12:35:26+00:00</updated>
<author>
<name>Laxman Acharya Padhya</name>
<email>acharyalaxman8848@gmail.com</email>
</author>
<published>2026-08-01T18:09:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6fc540e835dddb518cef3ff522b780f701cd03df'/>
<id>6fc540e835dddb518cef3ff522b780f701cd03df</id>
<content type='text'>
commit 0acd4eeb4b225b9bebbf9ef96cc10cdd79b94899 upstream.

The Command Complete dispatch validates only the fixed part of the LE Set
CIG Parameters response. After that part is pulled from the skb,
hci_cc_le_set_cig_params() trusts num_handles and reads each entry in the
trailing handle array.

Matching num_handles against the command's num_cis does not guarantee
that the response contains the advertised handles. A truncated response
from a malfunctioning controller can therefore make the handler read
beyond the skb data.

Validate that the remaining skb data contains all advertised handles.
Include this in the existing response validation so malformed responses
also follow the established CIG failure handling.

Fixes: 26afbd826ee3 ("Bluetooth: Add initial implementation of CIS connections")
Cc: stable@vger.kernel.org
Signed-off-by: Laxman Acharya Padhya &lt;acharyalaxman8848@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 0acd4eeb4b225b9bebbf9ef96cc10cdd79b94899 upstream.

The Command Complete dispatch validates only the fixed part of the LE Set
CIG Parameters response. After that part is pulled from the skb,
hci_cc_le_set_cig_params() trusts num_handles and reads each entry in the
trailing handle array.

Matching num_handles against the command's num_cis does not guarantee
that the response contains the advertised handles. A truncated response
from a malfunctioning controller can therefore make the handler read
beyond the skb data.

Validate that the remaining skb data contains all advertised handles.
Include this in the existing response validation so malformed responses
also follow the established CIG failure handling.

Fixes: 26afbd826ee3 ("Bluetooth: Add initial implementation of CIS connections")
Cc: stable@vger.kernel.org
Signed-off-by: Laxman Acharya Padhya &lt;acharyalaxman8848@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: hci_event: fix LE list UAF on reset</title>
<updated>2026-08-27T12:35:26+00:00</updated>
<author>
<name>Chengfeng Ye</name>
<email>nicoyip.dev@gmail.com</email>
</author>
<published>2026-07-30T08:32:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=25b05e3ce31d954540e99954bcc66cbceb27ab35'/>
<id>25b05e3ce31d954540e99954bcc66cbceb27ab35</id>
<content type='text'>
commit 33af47e847fe4a28b109673affb5874015d54f5a upstream.

hci_cc_reset() clears the LE accept and resolving lists without taking
hdev-&gt;lock. Other command-complete handlers serialize updates to these
lists with that lock, and the debugfs readers hold it while walking them.

This permits the reset completion and a debugfs read to interleave as
follows:

  hci_rx_work                 debugfs reader
  -----------                 --------------
                              lock hdev-&gt;lock
                              fetch current entry
  list_del(entry)
  kfree(entry)
                              read entry fields

The reader then dereferences a freed list entry and may follow its stale
next pointer.

KASAN reported:

  BUG: KASAN: slab-use-after-free in white_list_show+0x15f/0x180
  Read of size 1 at addr ffff8881015dab16 by task poc/95

  Call Trace:
   white_list_show+0x15f/0x180
   seq_read_iter+0x3ff/0x1190
   seq_read+0x267/0x3d0
   vfs_read+0x177/0xa20
   ksys_read+0xf7/0x1c0

  Allocated by task 91:
   hci_bdaddr_list_add+0x1a6/0x3a0
   hci_cc_le_add_to_accept_list+0xab/0x140
   hci_cmd_complete_evt+0x26c/0x9a0
   hci_event_packet+0x454/0xb20
   hci_rx_work+0x293/0x730

  Freed by task 90:
   kfree+0x131/0x3c0
   hci_bdaddr_list_clear+0xd8/0x160
   hci_cc_reset+0x28a/0x370
   hci_cmd_complete_evt+0x26c/0x9a0
   hci_event_packet+0x454/0xb20
   hci_rx_work+0x293/0x730

Take hdev-&gt;lock around both list clears. This matches the existing
mutation and traversal locking convention.

Fixes: a4d5504d5c39 ("Bluetooth: Clear LE white list when resetting controller")
Fixes: cfdb0c2d095a ("Bluetooth: Store Resolv list size")
Cc: stable@vger.kernel.org
Signed-off-by: Chengfeng Ye &lt;nicoyip.dev@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 33af47e847fe4a28b109673affb5874015d54f5a upstream.

hci_cc_reset() clears the LE accept and resolving lists without taking
hdev-&gt;lock. Other command-complete handlers serialize updates to these
lists with that lock, and the debugfs readers hold it while walking them.

This permits the reset completion and a debugfs read to interleave as
follows:

  hci_rx_work                 debugfs reader
  -----------                 --------------
                              lock hdev-&gt;lock
                              fetch current entry
  list_del(entry)
  kfree(entry)
                              read entry fields

The reader then dereferences a freed list entry and may follow its stale
next pointer.

KASAN reported:

  BUG: KASAN: slab-use-after-free in white_list_show+0x15f/0x180
  Read of size 1 at addr ffff8881015dab16 by task poc/95

  Call Trace:
   white_list_show+0x15f/0x180
   seq_read_iter+0x3ff/0x1190
   seq_read+0x267/0x3d0
   vfs_read+0x177/0xa20
   ksys_read+0xf7/0x1c0

  Allocated by task 91:
   hci_bdaddr_list_add+0x1a6/0x3a0
   hci_cc_le_add_to_accept_list+0xab/0x140
   hci_cmd_complete_evt+0x26c/0x9a0
   hci_event_packet+0x454/0xb20
   hci_rx_work+0x293/0x730

  Freed by task 90:
   kfree+0x131/0x3c0
   hci_bdaddr_list_clear+0xd8/0x160
   hci_cc_reset+0x28a/0x370
   hci_cmd_complete_evt+0x26c/0x9a0
   hci_event_packet+0x454/0xb20
   hci_rx_work+0x293/0x730

Take hdev-&gt;lock around both list clears. This matches the existing
mutation and traversal locking convention.

Fixes: a4d5504d5c39 ("Bluetooth: Clear LE white list when resetting controller")
Fixes: cfdb0c2d095a ("Bluetooth: Store Resolv list size")
Cc: stable@vger.kernel.org
Signed-off-by: Chengfeng Ye &lt;nicoyip.dev@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: RFCOMM: take rfcomm_mutex for the deferred setup accept</title>
<updated>2026-08-27T12:35:21+00:00</updated>
<author>
<name>Ali Ahmet Memis</name>
<email>ali@iusegentoo.com</email>
</author>
<published>2026-08-07T02:03:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b405c2f96ae2e37375105881890f7738833b1d62'/>
<id>b405c2f96ae2e37375105881890f7738833b1d62</id>
<content type='text'>
commit 43a556b2fd43f2df6dded59c2e26560a27874c24 upstream.

rfcomm_sock_recvmsg() completes a deferred setup by calling
rfcomm_dlc_accept() without holding any RFCOMM lock:

	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &amp;d-&gt;flags)) {
		rfcomm_dlc_accept(d);
		return 0;
	}

and rfcomm_dlc_accept() dereferences the session on its first line:

	struct sock *sk = d-&gt;session-&gt;sock-&gt;sk;

Every other path that touches d-&gt;session runs under rfcomm_mutex:
rfcomm_dlc_open(), rfcomm_dlc_close(), rfcomm_dlc_exists(),
rfcomm_dlc_send_rpn(), and the RFCOMM thread through
rfcomm_process_sessions(). rfcomm_connect_ind() is even documented as
"called under rfcomm_lock()". This call site is the only one that skips
it.

The RFCOMM_DEFER_SETUP bit looks like it serialises the accept against
teardown, since __rfcomm_dlc_close() returns early when it wins the
test_and_clear. But rfcomm_recv_disc() forces the state first:

	d-&gt;state = BT_CLOSED;
	__rfcomm_dlc_close(d, err);

and the early return only covers BT_CONNECT, BT_CONFIG, BT_OPEN and
BT_CONNECT2. With the state already BT_CLOSED that switch does not
match, the bit is never consulted, and __rfcomm_dlc_close() falls
through to rfcomm_dlc_unlink(), which sets d-&gt;session = NULL.

So a remote DISC on a deferred dlc clears the session while leaving
RFCOMM_DEFER_SETUP set. The next recvmsg() then passes the
test_and_clear and dereferences a NULL session. No timing window is
needed: once the DISC has been processed, the dereference is
unconditional.

Give rfcomm_dlc_accept() the same shape as rfcomm_dlc_open() and
rfcomm_dlc_close(): an exported wrapper that takes rfcomm_mutex and
re-checks the session, around a __rfcomm_dlc_accept() that the two
in-core callers, which already hold the mutex, keep using.

Reproduced on a KASAN + PROVE_LOCKING kernel with a BR/EDR peer emulated
over /dev/vhci: the peer brings up an ACL link, opens L2CAP on the
RFCOMM PSM, starts a session, opens a dlc on a channel bound with
BT_DEFER_SETUP, and sends DISC after the socket is accepted. recv() on
the accepted socket then hits:

  Oops: general protection fault
  KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
  RIP: 0010:rfcomm_dlc_accept+0x54/0x350
  Call Trace:
    rfcomm_sock_recvmsg+0x1cd/0x230
    sock_recvmsg+0x166/0x1c0
    __sys_recvfrom+0x20d/0x300

0x10 is the offset of sock in struct rfcomm_session. With this patch the
same run completes with recv() returning 0 and no report, and lockdep
stays quiet, confirming rfcomm_mutex is still taken before lock_sock on
this path as it is on the thread side.

Fixes: bb23c0ab8246 ("Bluetooth: Add support for deferring RFCOMM connection setup")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&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 43a556b2fd43f2df6dded59c2e26560a27874c24 upstream.

rfcomm_sock_recvmsg() completes a deferred setup by calling
rfcomm_dlc_accept() without holding any RFCOMM lock:

	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &amp;d-&gt;flags)) {
		rfcomm_dlc_accept(d);
		return 0;
	}

and rfcomm_dlc_accept() dereferences the session on its first line:

	struct sock *sk = d-&gt;session-&gt;sock-&gt;sk;

Every other path that touches d-&gt;session runs under rfcomm_mutex:
rfcomm_dlc_open(), rfcomm_dlc_close(), rfcomm_dlc_exists(),
rfcomm_dlc_send_rpn(), and the RFCOMM thread through
rfcomm_process_sessions(). rfcomm_connect_ind() is even documented as
"called under rfcomm_lock()". This call site is the only one that skips
it.

The RFCOMM_DEFER_SETUP bit looks like it serialises the accept against
teardown, since __rfcomm_dlc_close() returns early when it wins the
test_and_clear. But rfcomm_recv_disc() forces the state first:

	d-&gt;state = BT_CLOSED;
	__rfcomm_dlc_close(d, err);

and the early return only covers BT_CONNECT, BT_CONFIG, BT_OPEN and
BT_CONNECT2. With the state already BT_CLOSED that switch does not
match, the bit is never consulted, and __rfcomm_dlc_close() falls
through to rfcomm_dlc_unlink(), which sets d-&gt;session = NULL.

So a remote DISC on a deferred dlc clears the session while leaving
RFCOMM_DEFER_SETUP set. The next recvmsg() then passes the
test_and_clear and dereferences a NULL session. No timing window is
needed: once the DISC has been processed, the dereference is
unconditional.

Give rfcomm_dlc_accept() the same shape as rfcomm_dlc_open() and
rfcomm_dlc_close(): an exported wrapper that takes rfcomm_mutex and
re-checks the session, around a __rfcomm_dlc_accept() that the two
in-core callers, which already hold the mutex, keep using.

Reproduced on a KASAN + PROVE_LOCKING kernel with a BR/EDR peer emulated
over /dev/vhci: the peer brings up an ACL link, opens L2CAP on the
RFCOMM PSM, starts a session, opens a dlc on a channel bound with
BT_DEFER_SETUP, and sends DISC after the socket is accepted. recv() on
the accepted socket then hits:

  Oops: general protection fault
  KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
  RIP: 0010:rfcomm_dlc_accept+0x54/0x350
  Call Trace:
    rfcomm_sock_recvmsg+0x1cd/0x230
    sock_recvmsg+0x166/0x1c0
    __sys_recvfrom+0x20d/0x300

0x10 is the offset of sock in struct rfcomm_session. With this patch the
same run completes with recv() returning 0 and no report, and lockdep
stays quiet, confirming rfcomm_mutex is still taken before lock_sock on
this path as it is on the thread side.

Fixes: bb23c0ab8246 ("Bluetooth: Add support for deferring RFCOMM connection setup")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis &lt;ali@iusegentoo.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: SCO: give the socket its own sco_conn reference</title>
<updated>2026-07-28T20:13:48+00:00</updated>
<author>
<name>Aldo Ariel Panzardo</name>
<email>qwe.aldo@gmail.com</email>
</author>
<published>2026-07-25T19:52:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=abd93c85c8667add738ee82aeab95dd9fc8265a2'/>
<id>abd93c85c8667add738ee82aeab95dd9fc8265a2</id>
<content type='text'>
sco_conn_del() drops a reference it does not own. It takes one transient
reference via sco_conn_hold_unless_zero() and releases it with the
sco_conn_put() that follows sco_sock_hold(); the additional put in the
!sk branch releases a second one:

    conn = sco_conn_hold_unless_zero(conn);
    ...
    sk = sco_sock_hold(conn);
    sco_conn_unlock(conn);
    sco_conn_put(conn);

    if (!sk) {
            sco_conn_put(conn);
            return;
    }

When close() races the controller's Disconnection Complete, sco_chan_del()
clears conn-&gt;sk and drops the socket's reference while sco_conn_del() is
running. sco_conn_del() then sees sk == NULL, its own put drops the count
to zero and frees the conn, and the second put writes to the freed kref:

    BUG: KASAN: slab-use-after-free in sco_conn_put.part.0+0x1a/0x190
    Write of size 4 at addr ffff8881099dec74 by task kworker/u17:3/413
    Workqueue: hci1 hci_rx_work
    Call Trace:
     sco_conn_put.part.0+0x1a/0x190
     hci_disconn_complete_evt+0x1ee/0x3e0
     hci_event_packet+0x54a/0x650
     hci_rx_work+0x321/0x3d0
    Allocated by task 413:
     sco_conn_add+0x72/0x1a0
     sco_connect_cfm+0x88/0x670
    Freed by task 413:
     sco_conn_del.isra.0+0x3f/0xf0
     hci_disconn_complete_evt+0x1ee/0x3e0
    refcount_t: underflow; use-after-free.

The root cause is that the socket stores the connection without holding a
reference of its own. __sco_chan_add() does:

    sco_pi(sk)-&gt;conn = conn;

so the socket borrows whatever reference its caller happened to hold, and
the callers paper over that with ad-hoc holds and puts. Give the socket a
counted reference instead: __sco_chan_add() takes one and it is released
together with the channel (sco_chan_del()) and in sco_sock_destruct().
With the socket holding its own reference, sco_conn_del() no longer needs
the extra put and the redundant hold in sco_conn_ready() goes away.

Making the socket own its reference means the connection is now actually
freed on the error paths of sco_connect() where it used to leak, which in
turn runs sco_conn_free() and its hci_conn_drop(conn-&gt;hcon). To keep the
hci_conn accounting balanced, make that ownership explicit as well:
sco_conn_add() consumes one hci_conn reference and the sco_conn owns it for
its lifetime. sco_connect() hands over the reference returned by
hci_connect_sco() and no longer drops it on the error paths;
sco_connect_cfm(), which is not given a reference, takes one with
hci_conn_hold() before handing it to sco_conn_add() (and drops it again if
the allocation fails); and the explicit hci_conn_hold() in sco_conn_ready()
is removed. Every reference then has a single, clear owner.

Fixes: e6720779ae61 ("Bluetooth: SCO: Use kref to track lifetime of sco_conn")
Cc: stable@vger.kernel.org
Suggested-by: Pauli Virtanen &lt;pav@iki.fi&gt;
Signed-off-by: Aldo Ariel Panzardo &lt;qwe.aldo@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
sco_conn_del() drops a reference it does not own. It takes one transient
reference via sco_conn_hold_unless_zero() and releases it with the
sco_conn_put() that follows sco_sock_hold(); the additional put in the
!sk branch releases a second one:

    conn = sco_conn_hold_unless_zero(conn);
    ...
    sk = sco_sock_hold(conn);
    sco_conn_unlock(conn);
    sco_conn_put(conn);

    if (!sk) {
            sco_conn_put(conn);
            return;
    }

When close() races the controller's Disconnection Complete, sco_chan_del()
clears conn-&gt;sk and drops the socket's reference while sco_conn_del() is
running. sco_conn_del() then sees sk == NULL, its own put drops the count
to zero and frees the conn, and the second put writes to the freed kref:

    BUG: KASAN: slab-use-after-free in sco_conn_put.part.0+0x1a/0x190
    Write of size 4 at addr ffff8881099dec74 by task kworker/u17:3/413
    Workqueue: hci1 hci_rx_work
    Call Trace:
     sco_conn_put.part.0+0x1a/0x190
     hci_disconn_complete_evt+0x1ee/0x3e0
     hci_event_packet+0x54a/0x650
     hci_rx_work+0x321/0x3d0
    Allocated by task 413:
     sco_conn_add+0x72/0x1a0
     sco_connect_cfm+0x88/0x670
    Freed by task 413:
     sco_conn_del.isra.0+0x3f/0xf0
     hci_disconn_complete_evt+0x1ee/0x3e0
    refcount_t: underflow; use-after-free.

The root cause is that the socket stores the connection without holding a
reference of its own. __sco_chan_add() does:

    sco_pi(sk)-&gt;conn = conn;

so the socket borrows whatever reference its caller happened to hold, and
the callers paper over that with ad-hoc holds and puts. Give the socket a
counted reference instead: __sco_chan_add() takes one and it is released
together with the channel (sco_chan_del()) and in sco_sock_destruct().
With the socket holding its own reference, sco_conn_del() no longer needs
the extra put and the redundant hold in sco_conn_ready() goes away.

Making the socket own its reference means the connection is now actually
freed on the error paths of sco_connect() where it used to leak, which in
turn runs sco_conn_free() and its hci_conn_drop(conn-&gt;hcon). To keep the
hci_conn accounting balanced, make that ownership explicit as well:
sco_conn_add() consumes one hci_conn reference and the sco_conn owns it for
its lifetime. sco_connect() hands over the reference returned by
hci_connect_sco() and no longer drops it on the error paths;
sco_connect_cfm(), which is not given a reference, takes one with
hci_conn_hold() before handing it to sco_conn_add() (and drops it again if
the allocation fails); and the explicit hci_conn_hold() in sco_conn_ready()
is removed. Every reference then has a single, clear owner.

Fixes: e6720779ae61 ("Bluetooth: SCO: Use kref to track lifetime of sco_conn")
Cc: stable@vger.kernel.org
Suggested-by: Pauli Virtanen &lt;pav@iki.fi&gt;
Signed-off-by: Aldo Ariel Panzardo &lt;qwe.aldo@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: hci_sync: remove unnecessary hci_conn_get in create_conn_sync</title>
<updated>2026-07-28T20:13:13+00:00</updated>
<author>
<name>Pauli Virtanen</name>
<email>pav@iki.fi</email>
</author>
<published>2026-07-25T09:59:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c0a9dcd2be398eee505d4b254ec3a845aa8ab189'/>
<id>c0a9dcd2be398eee505d4b254ec3a845aa8ab189</id>
<content type='text'>
hci_conn_get() without already held reference is data race against
concurrent deletion.

In previous patches, the refcount has been changed to be taken before
starting the hci_sync task, so remove these extra get() + put() as they
are not needed.

Fixes: 12917f591cea ("Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()")
Signed-off-by: Pauli Virtanen &lt;pav@iki.fi&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
hci_conn_get() without already held reference is data race against
concurrent deletion.

In previous patches, the refcount has been changed to be taken before
starting the hci_sync task, so remove these extra get() + put() as they
are not needed.

Fixes: 12917f591cea ("Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()")
Signed-off-by: Pauli Virtanen &lt;pav@iki.fi&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: hci_sync: fix hci_conn_del() use in hci_le_create_conn_sync</title>
<updated>2026-07-28T20:13:13+00:00</updated>
<author>
<name>Pauli Virtanen</name>
<email>pav@iki.fi</email>
</author>
<published>2026-07-25T09:59:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2c1e4e00613dfd105f978be2276e5e265801ec9f'/>
<id>2c1e4e00613dfd105f978be2276e5e265801ec9f</id>
<content type='text'>
hci_conn_del() caller must hold hdev-&gt;lock, check the conn was not
concurrently deleted, and usually inform socket the conn is going to be
deleted.

Use hci_abort_conn_sync() instead of calling hci_conn_del() without
locks etc.

Fixes: 8e8b92ee60de5 ("Bluetooth: hci_sync: Add hci_le_create_conn_sync")
Signed-off-by: Pauli Virtanen &lt;pav@iki.fi&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
hci_conn_del() caller must hold hdev-&gt;lock, check the conn was not
concurrently deleted, and usually inform socket the conn is going to be
deleted.

Use hci_abort_conn_sync() instead of calling hci_conn_del() without
locks etc.

Fixes: 8e8b92ee60de5 ("Bluetooth: hci_sync: Add hci_le_create_conn_sync")
Signed-off-by: Pauli Virtanen &lt;pav@iki.fi&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
