<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/bluetooth, branch v5.4.192</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Bluetooth: Fix use after free in hci_send_acl</title>
<updated>2022-04-15T12:18:34+00:00</updated>
<author>
<name>Luiz Augusto von Dentz</name>
<email>luiz.von.dentz@intel.com</email>
</author>
<published>2022-03-11T21:19:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3803d896ddd97c7c16689a5381c0960040727647'/>
<id>3803d896ddd97c7c16689a5381c0960040727647</id>
<content type='text'>
[ Upstream commit f63d24baff787e13b723d86fe036f84bdbc35045 ]

This fixes the following trace caused by receiving
HCI_EV_DISCONN_PHY_LINK_COMPLETE which does call hci_conn_del without
first checking if conn-&gt;type is in fact AMP_LINK and in case it is
do properly cleanup upper layers with hci_disconn_cfm:

 ==================================================================
    BUG: KASAN: use-after-free in hci_send_acl+0xaba/0xc50
    Read of size 8 at addr ffff88800e404818 by task bluetoothd/142

    CPU: 0 PID: 142 Comm: bluetoothd Not tainted
    5.17.0-rc5-00006-gda4022eeac1a #7
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
    rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
    Call Trace:
     &lt;TASK&gt;
     dump_stack_lvl+0x45/0x59
     print_address_description.constprop.0+0x1f/0x150
     kasan_report.cold+0x7f/0x11b
     hci_send_acl+0xaba/0xc50
     l2cap_do_send+0x23f/0x3d0
     l2cap_chan_send+0xc06/0x2cc0
     l2cap_sock_sendmsg+0x201/0x2b0
     sock_sendmsg+0xdc/0x110
     sock_write_iter+0x20f/0x370
     do_iter_readv_writev+0x343/0x690
     do_iter_write+0x132/0x640
     vfs_writev+0x198/0x570
     do_writev+0x202/0x280
     do_syscall_64+0x38/0x90
     entry_SYSCALL_64_after_hwframe+0x44/0xae
    RSP: 002b:00007ffce8a099b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
    Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3
    0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 14 00 00 00 0f 05
    &lt;48&gt; 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
    RDX: 0000000000000001 RSI: 00007ffce8a099e0 RDI: 0000000000000015
    RAX: ffffffffffffffda RBX: 00007ffce8a099e0 RCX: 00007f788fc3cf77
    R10: 00007ffce8af7080 R11: 0000000000000246 R12: 000055e4ccf75580
    RBP: 0000000000000015 R08: 0000000000000002 R09: 0000000000000001
    &lt;/TASK&gt;
    R13: 000055e4ccf754a0 R14: 000055e4ccf75cd0 R15: 000055e4ccf4a6b0

    Allocated by task 45:
        kasan_save_stack+0x1e/0x40
        __kasan_kmalloc+0x81/0xa0
        hci_chan_create+0x9a/0x2f0
        l2cap_conn_add.part.0+0x1a/0xdc0
        l2cap_connect_cfm+0x236/0x1000
        le_conn_complete_evt+0x15a7/0x1db0
        hci_le_conn_complete_evt+0x226/0x2c0
        hci_le_meta_evt+0x247/0x450
        hci_event_packet+0x61b/0xe90
        hci_rx_work+0x4d5/0xc50
        process_one_work+0x8fb/0x15a0
        worker_thread+0x576/0x1240
        kthread+0x29d/0x340
        ret_from_fork+0x1f/0x30

    Freed by task 45:
        kasan_save_stack+0x1e/0x40
        kasan_set_track+0x21/0x30
        kasan_set_free_info+0x20/0x30
        __kasan_slab_free+0xfb/0x130
        kfree+0xac/0x350
        hci_conn_cleanup+0x101/0x6a0
        hci_conn_del+0x27e/0x6c0
        hci_disconn_phylink_complete_evt+0xe0/0x120
        hci_event_packet+0x812/0xe90
        hci_rx_work+0x4d5/0xc50
        process_one_work+0x8fb/0x15a0
        worker_thread+0x576/0x1240
        kthread+0x29d/0x340
        ret_from_fork+0x1f/0x30

    The buggy address belongs to the object at ffff88800c0f0500
    The buggy address is located 24 bytes inside of
    which belongs to the cache kmalloc-128 of size 128
    The buggy address belongs to the page:
    128-byte region [ffff88800c0f0500, ffff88800c0f0580)
    flags: 0x100000000000200(slab|node=0|zone=1)
    page:00000000fe45cd86 refcount:1 mapcount:0
    mapping:0000000000000000 index:0x0 pfn:0xc0f0
    raw: 0000000000000000 0000000080100010 00000001ffffffff
    0000000000000000
    raw: 0100000000000200 ffffea00003a2c80 dead000000000004
    ffff8880078418c0
    page dumped because: kasan: bad access detected
    ffff88800c0f0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
    Memory state around the buggy address:
    &gt;ffff88800c0f0500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
    ffff88800c0f0480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
    ffff88800c0f0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                ^
    ==================================================================
    ffff88800c0f0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Reported-by: Sönke Huster &lt;soenke.huster@eknoes.de&gt;
Tested-by: Sönke Huster &lt;soenke.huster@eknoes.de&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f63d24baff787e13b723d86fe036f84bdbc35045 ]

This fixes the following trace caused by receiving
HCI_EV_DISCONN_PHY_LINK_COMPLETE which does call hci_conn_del without
first checking if conn-&gt;type is in fact AMP_LINK and in case it is
do properly cleanup upper layers with hci_disconn_cfm:

 ==================================================================
    BUG: KASAN: use-after-free in hci_send_acl+0xaba/0xc50
    Read of size 8 at addr ffff88800e404818 by task bluetoothd/142

    CPU: 0 PID: 142 Comm: bluetoothd Not tainted
    5.17.0-rc5-00006-gda4022eeac1a #7
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
    rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
    Call Trace:
     &lt;TASK&gt;
     dump_stack_lvl+0x45/0x59
     print_address_description.constprop.0+0x1f/0x150
     kasan_report.cold+0x7f/0x11b
     hci_send_acl+0xaba/0xc50
     l2cap_do_send+0x23f/0x3d0
     l2cap_chan_send+0xc06/0x2cc0
     l2cap_sock_sendmsg+0x201/0x2b0
     sock_sendmsg+0xdc/0x110
     sock_write_iter+0x20f/0x370
     do_iter_readv_writev+0x343/0x690
     do_iter_write+0x132/0x640
     vfs_writev+0x198/0x570
     do_writev+0x202/0x280
     do_syscall_64+0x38/0x90
     entry_SYSCALL_64_after_hwframe+0x44/0xae
    RSP: 002b:00007ffce8a099b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
    Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3
    0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 14 00 00 00 0f 05
    &lt;48&gt; 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
    RDX: 0000000000000001 RSI: 00007ffce8a099e0 RDI: 0000000000000015
    RAX: ffffffffffffffda RBX: 00007ffce8a099e0 RCX: 00007f788fc3cf77
    R10: 00007ffce8af7080 R11: 0000000000000246 R12: 000055e4ccf75580
    RBP: 0000000000000015 R08: 0000000000000002 R09: 0000000000000001
    &lt;/TASK&gt;
    R13: 000055e4ccf754a0 R14: 000055e4ccf75cd0 R15: 000055e4ccf4a6b0

    Allocated by task 45:
        kasan_save_stack+0x1e/0x40
        __kasan_kmalloc+0x81/0xa0
        hci_chan_create+0x9a/0x2f0
        l2cap_conn_add.part.0+0x1a/0xdc0
        l2cap_connect_cfm+0x236/0x1000
        le_conn_complete_evt+0x15a7/0x1db0
        hci_le_conn_complete_evt+0x226/0x2c0
        hci_le_meta_evt+0x247/0x450
        hci_event_packet+0x61b/0xe90
        hci_rx_work+0x4d5/0xc50
        process_one_work+0x8fb/0x15a0
        worker_thread+0x576/0x1240
        kthread+0x29d/0x340
        ret_from_fork+0x1f/0x30

    Freed by task 45:
        kasan_save_stack+0x1e/0x40
        kasan_set_track+0x21/0x30
        kasan_set_free_info+0x20/0x30
        __kasan_slab_free+0xfb/0x130
        kfree+0xac/0x350
        hci_conn_cleanup+0x101/0x6a0
        hci_conn_del+0x27e/0x6c0
        hci_disconn_phylink_complete_evt+0xe0/0x120
        hci_event_packet+0x812/0xe90
        hci_rx_work+0x4d5/0xc50
        process_one_work+0x8fb/0x15a0
        worker_thread+0x576/0x1240
        kthread+0x29d/0x340
        ret_from_fork+0x1f/0x30

    The buggy address belongs to the object at ffff88800c0f0500
    The buggy address is located 24 bytes inside of
    which belongs to the cache kmalloc-128 of size 128
    The buggy address belongs to the page:
    128-byte region [ffff88800c0f0500, ffff88800c0f0580)
    flags: 0x100000000000200(slab|node=0|zone=1)
    page:00000000fe45cd86 refcount:1 mapcount:0
    mapping:0000000000000000 index:0x0 pfn:0xc0f0
    raw: 0000000000000000 0000000080100010 00000001ffffffff
    0000000000000000
    raw: 0100000000000200 ffffea00003a2c80 dead000000000004
    ffff8880078418c0
    page dumped because: kasan: bad access detected
    ffff88800c0f0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
    Memory state around the buggy address:
    &gt;ffff88800c0f0500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
    ffff88800c0f0480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
    ffff88800c0f0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                ^
    ==================================================================
    ffff88800c0f0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Reported-by: Sönke Huster &lt;soenke.huster@eknoes.de&gt;
Tested-by: Sönke Huster &lt;soenke.huster@eknoes.de&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: refactor malicious adv data check</title>
<updated>2022-02-01T16:24:33+00:00</updated>
<author>
<name>Brian Gix</name>
<email>brian.gix@intel.com</email>
</author>
<published>2021-11-24T20:16:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=835d3706852537bf92eb23eb8635b8dee0c0aa67'/>
<id>835d3706852537bf92eb23eb8635b8dee0c0aa67</id>
<content type='text'>
commit 899663be5e75dc0174dc8bda0b5e6826edf0b29a upstream.

Check for out-of-bound read was being performed at the end of while
num_reports loop, and would fill journal with false positives. Added
check to beginning of loop processing so that it doesn't get checked
after ptr has been advanced.

Signed-off-by: Brian Gix &lt;brian.gix@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Cc: syphyr &lt;syphyr@gmail.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 899663be5e75dc0174dc8bda0b5e6826edf0b29a upstream.

Check for out-of-bound read was being performed at the end of while
num_reports loop, and would fill journal with false positives. Added
check to beginning of loop processing so that it doesn't get checked
after ptr has been advanced.

Signed-off-by: Brian Gix &lt;brian.gix@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Cc: syphyr &lt;syphyr@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: Fix debugfs entry leak in hci_register_dev()</title>
<updated>2022-01-27T08:19:40+00:00</updated>
<author>
<name>Wei Yongjun</name>
<email>weiyongjun1@huawei.com</email>
</author>
<published>2021-10-13T08:55:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa4ca508c25c674d75fb7d954dbf023466a2ed08'/>
<id>fa4ca508c25c674d75fb7d954dbf023466a2ed08</id>
<content type='text'>
[ Upstream commit 5a4bb6a8e981d3d0d492aa38412ee80b21033177 ]

Fault injection test report debugfs entry leak as follows:

debugfs: Directory 'hci0' with parent 'bluetooth' already present!

When register_pm_notifier() failed in hci_register_dev(), the debugfs
create by debugfs_create_dir() do not removed in the error handing path.

Add the remove debugfs code to fix it.

Signed-off-by: Wei Yongjun &lt;weiyongjun1@huawei.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 5a4bb6a8e981d3d0d492aa38412ee80b21033177 ]

Fault injection test report debugfs entry leak as follows:

debugfs: Directory 'hci0' with parent 'bluetooth' already present!

When register_pm_notifier() failed in hci_register_dev(), the debugfs
create by debugfs_create_dir() do not removed in the error handing path.

Add the remove debugfs code to fix it.

Signed-off-by: Wei Yongjun &lt;weiyongjun1@huawei.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: stop proccessing malicious adv data</title>
<updated>2022-01-27T08:19:30+00:00</updated>
<author>
<name>Pavel Skripkin</name>
<email>paskripkin@gmail.com</email>
</author>
<published>2021-11-01T07:12:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=24161b9c43de966789d5956428f45002d10f878e'/>
<id>24161b9c43de966789d5956428f45002d10f878e</id>
<content type='text'>
[ Upstream commit 3a56ef719f0b9682afb8a86d64b2399e36faa4e6 ]

Syzbot reported slab-out-of-bounds read in hci_le_adv_report_evt(). The
problem was in missing validaion check.

We should check if data is not malicious and we can read next data block.
If we won't check ptr validness, code can read a way beyond skb-&gt;end and
it can cause problems, of course.

Fixes: e95beb414168 ("Bluetooth: hci_le_adv_report_evt code refactoring")
Reported-and-tested-by: syzbot+e3fcb9c4f3c2a931dc40@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin &lt;paskripkin@gmail.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 3a56ef719f0b9682afb8a86d64b2399e36faa4e6 ]

Syzbot reported slab-out-of-bounds read in hci_le_adv_report_evt(). The
problem was in missing validaion check.

We should check if data is not malicious and we can read next data block.
If we won't check ptr validness, code can read a way beyond skb-&gt;end and
it can cause problems, of course.

Fixes: e95beb414168 ("Bluetooth: hci_le_adv_report_evt code refactoring")
Reported-and-tested-by: syzbot+e3fcb9c4f3c2a931dc40@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin &lt;paskripkin@gmail.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: cmtp: fix possible panic when cmtp_init_sockets() fails</title>
<updated>2022-01-27T08:19:29+00:00</updated>
<author>
<name>Wang Hai</name>
<email>wanghai38@huawei.com</email>
</author>
<published>2021-10-25T13:10:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ba4cc4968917f72c5c76f8bc5d4a19687e573de6'/>
<id>ba4cc4968917f72c5c76f8bc5d4a19687e573de6</id>
<content type='text'>
[ Upstream commit 2a7ca7459d905febf519163bd9e3eed894de6bb7 ]

I got a kernel BUG report when doing fault injection test:

------------[ cut here ]------------
kernel BUG at lib/list_debug.c:45!
...
RIP: 0010:__list_del_entry_valid.cold+0x12/0x4d
...
Call Trace:
 proto_unregister+0x83/0x220
 cmtp_cleanup_sockets+0x37/0x40 [cmtp]
 cmtp_exit+0xe/0x1f [cmtp]
 do_syscall_64+0x35/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

If cmtp_init_sockets() in cmtp_init() fails, cmtp_init() still returns
success. This will cause a kernel bug when accessing uncreated ctmp
related data when the module exits.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Signed-off-by: Wang Hai &lt;wanghai38@huawei.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2a7ca7459d905febf519163bd9e3eed894de6bb7 ]

I got a kernel BUG report when doing fault injection test:

------------[ cut here ]------------
kernel BUG at lib/list_debug.c:45!
...
RIP: 0010:__list_del_entry_valid.cold+0x12/0x4d
...
Call Trace:
 proto_unregister+0x83/0x220
 cmtp_cleanup_sockets+0x37/0x40 [cmtp]
 cmtp_exit+0xe/0x1f [cmtp]
 do_syscall_64+0x35/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

If cmtp_init_sockets() in cmtp_init() fails, cmtp_init() still returns
success. This will cause a kernel bug when accessing uncreated ctmp
related data when the module exits.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Signed-off-by: Wang Hai &lt;wanghai38@huawei.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: fix init and cleanup of sco_conn.timeout_work</title>
<updated>2021-11-17T08:48:33+00:00</updated>
<author>
<name>Desmond Cheong Zhi Xi</name>
<email>desmondcheongzx@gmail.com</email>
</author>
<published>2021-09-03T03:13:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6237a1685c28c93b6477db46fbf67b7f0a0139e6'/>
<id>6237a1685c28c93b6477db46fbf67b7f0a0139e6</id>
<content type='text'>
[ Upstream commit 49d8a5606428ca0962d09050a5af81461ff90fbb ]

Before freeing struct sco_conn, all delayed timeout work should be
cancelled. Otherwise, sco_sock_timeout could potentially use the
sco_conn after it has been freed.

Additionally, sco_conn.timeout_work should be initialized when the
connection is allocated, not when the channel is added. This is
because an sco_conn can create channels with multiple sockets over its
lifetime, which happens if sockets are released but the connection
isn't deleted.

Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work")
Signed-off-by: Desmond Cheong Zhi Xi &lt;desmondcheongzx@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 49d8a5606428ca0962d09050a5af81461ff90fbb ]

Before freeing struct sco_conn, all delayed timeout work should be
cancelled. Otherwise, sco_sock_timeout could potentially use the
sco_conn after it has been freed.

Additionally, sco_conn.timeout_work should be initialized when the
connection is allocated, not when the channel is added. This is
because an sco_conn can create channels with multiple sockets over its
lifetime, which happens if sockets are released but the connection
isn't deleted.

Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work")
Signed-off-by: Desmond Cheong Zhi Xi &lt;desmondcheongzx@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: fix use-after-free error in lock_sock_nested()</title>
<updated>2021-11-17T08:48:27+00:00</updated>
<author>
<name>Wang ShaoBo</name>
<email>bobo.shaobowang@huawei.com</email>
</author>
<published>2021-09-01T00:35:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=67bd269a84ce29dfc543c1683a2553b4169f9a55'/>
<id>67bd269a84ce29dfc543c1683a2553b4169f9a55</id>
<content type='text'>
[ Upstream commit 1bff51ea59a9afb67d2dd78518ab0582a54a472c ]

use-after-free error in lock_sock_nested is reported:

[  179.140137][ T3731] =====================================================
[  179.142675][ T3731] BUG: KMSAN: use-after-free in lock_sock_nested+0x280/0x2c0
[  179.145494][ T3731] CPU: 4 PID: 3731 Comm: kworker/4:2 Not tainted 5.12.0-rc6+ #54
[  179.148432][ T3731] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[  179.151806][ T3731] Workqueue: events l2cap_chan_timeout
[  179.152730][ T3731] Call Trace:
[  179.153301][ T3731]  dump_stack+0x24c/0x2e0
[  179.154063][ T3731]  kmsan_report+0xfb/0x1e0
[  179.154855][ T3731]  __msan_warning+0x5c/0xa0
[  179.155579][ T3731]  lock_sock_nested+0x280/0x2c0
[  179.156436][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.157257][ T3731]  l2cap_sock_teardown_cb+0xb8/0x890
[  179.158154][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.159141][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.159994][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.160959][ T3731]  ? l2cap_sock_recv_cb+0x420/0x420
[  179.161834][ T3731]  l2cap_chan_del+0x3e1/0x1d50
[  179.162608][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.163435][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.164406][ T3731]  l2cap_chan_close+0xeea/0x1050
[  179.165189][ T3731]  ? kmsan_internal_unpoison_shadow+0x42/0x70
[  179.166180][ T3731]  l2cap_chan_timeout+0x1da/0x590
[  179.167066][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.168023][ T3731]  ? l2cap_chan_create+0x560/0x560
[  179.168818][ T3731]  process_one_work+0x121d/0x1ff0
[  179.169598][ T3731]  worker_thread+0x121b/0x2370
[  179.170346][ T3731]  kthread+0x4ef/0x610
[  179.171010][ T3731]  ? process_one_work+0x1ff0/0x1ff0
[  179.171828][ T3731]  ? kthread_blkcg+0x110/0x110
[  179.172587][ T3731]  ret_from_fork+0x1f/0x30
[  179.173348][ T3731]
[  179.173752][ T3731] Uninit was created at:
[  179.174409][ T3731]  kmsan_internal_poison_shadow+0x5c/0xf0
[  179.175373][ T3731]  kmsan_slab_free+0x76/0xc0
[  179.176060][ T3731]  kfree+0x3a5/0x1180
[  179.176664][ T3731]  __sk_destruct+0x8af/0xb80
[  179.177375][ T3731]  __sk_free+0x812/0x8c0
[  179.178032][ T3731]  sk_free+0x97/0x130
[  179.178686][ T3731]  l2cap_sock_release+0x3d5/0x4d0
[  179.179457][ T3731]  sock_close+0x150/0x450
[  179.180117][ T3731]  __fput+0x6bd/0xf00
[  179.180787][ T3731]  ____fput+0x37/0x40
[  179.181481][ T3731]  task_work_run+0x140/0x280
[  179.182219][ T3731]  do_exit+0xe51/0x3e60
[  179.182930][ T3731]  do_group_exit+0x20e/0x450
[  179.183656][ T3731]  get_signal+0x2dfb/0x38f0
[  179.184344][ T3731]  arch_do_signal_or_restart+0xaa/0xe10
[  179.185266][ T3731]  exit_to_user_mode_prepare+0x2d2/0x560
[  179.186136][ T3731]  syscall_exit_to_user_mode+0x35/0x60
[  179.186984][ T3731]  do_syscall_64+0xc5/0x140
[  179.187681][ T3731]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  179.188604][ T3731] =====================================================

In our case, there are two Thread A and B:

Context: Thread A:              Context: Thread B:

l2cap_chan_timeout()            __se_sys_shutdown()
  l2cap_chan_close()              l2cap_sock_shutdown()
    l2cap_chan_del()                l2cap_chan_close()
      l2cap_sock_teardown_cb()        l2cap_sock_teardown_cb()

Once l2cap_sock_teardown_cb() excuted, this sock will be marked as SOCK_ZAPPED,
and can be treated as killable in l2cap_sock_kill() if sock_orphan() has
excuted, at this time we close sock through sock_close() which end to call
l2cap_sock_kill() like Thread C:

Context: Thread C:

sock_close()
  l2cap_sock_release()
    sock_orphan()
    l2cap_sock_kill()  #free sock if refcnt is 1

If C completed, Once A or B reaches l2cap_sock_teardown_cb() again,
use-after-free happened.

We should set chan-&gt;data to NULL if sock is destructed, for telling teardown
operation is not allowed in l2cap_sock_teardown_cb(), and also we should
avoid killing an already killed socket in l2cap_sock_close_cb().

Signed-off-by: Wang ShaoBo &lt;bobo.shaobowang@huawei.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1bff51ea59a9afb67d2dd78518ab0582a54a472c ]

use-after-free error in lock_sock_nested is reported:

[  179.140137][ T3731] =====================================================
[  179.142675][ T3731] BUG: KMSAN: use-after-free in lock_sock_nested+0x280/0x2c0
[  179.145494][ T3731] CPU: 4 PID: 3731 Comm: kworker/4:2 Not tainted 5.12.0-rc6+ #54
[  179.148432][ T3731] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[  179.151806][ T3731] Workqueue: events l2cap_chan_timeout
[  179.152730][ T3731] Call Trace:
[  179.153301][ T3731]  dump_stack+0x24c/0x2e0
[  179.154063][ T3731]  kmsan_report+0xfb/0x1e0
[  179.154855][ T3731]  __msan_warning+0x5c/0xa0
[  179.155579][ T3731]  lock_sock_nested+0x280/0x2c0
[  179.156436][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.157257][ T3731]  l2cap_sock_teardown_cb+0xb8/0x890
[  179.158154][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.159141][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.159994][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.160959][ T3731]  ? l2cap_sock_recv_cb+0x420/0x420
[  179.161834][ T3731]  l2cap_chan_del+0x3e1/0x1d50
[  179.162608][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.163435][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.164406][ T3731]  l2cap_chan_close+0xeea/0x1050
[  179.165189][ T3731]  ? kmsan_internal_unpoison_shadow+0x42/0x70
[  179.166180][ T3731]  l2cap_chan_timeout+0x1da/0x590
[  179.167066][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.168023][ T3731]  ? l2cap_chan_create+0x560/0x560
[  179.168818][ T3731]  process_one_work+0x121d/0x1ff0
[  179.169598][ T3731]  worker_thread+0x121b/0x2370
[  179.170346][ T3731]  kthread+0x4ef/0x610
[  179.171010][ T3731]  ? process_one_work+0x1ff0/0x1ff0
[  179.171828][ T3731]  ? kthread_blkcg+0x110/0x110
[  179.172587][ T3731]  ret_from_fork+0x1f/0x30
[  179.173348][ T3731]
[  179.173752][ T3731] Uninit was created at:
[  179.174409][ T3731]  kmsan_internal_poison_shadow+0x5c/0xf0
[  179.175373][ T3731]  kmsan_slab_free+0x76/0xc0
[  179.176060][ T3731]  kfree+0x3a5/0x1180
[  179.176664][ T3731]  __sk_destruct+0x8af/0xb80
[  179.177375][ T3731]  __sk_free+0x812/0x8c0
[  179.178032][ T3731]  sk_free+0x97/0x130
[  179.178686][ T3731]  l2cap_sock_release+0x3d5/0x4d0
[  179.179457][ T3731]  sock_close+0x150/0x450
[  179.180117][ T3731]  __fput+0x6bd/0xf00
[  179.180787][ T3731]  ____fput+0x37/0x40
[  179.181481][ T3731]  task_work_run+0x140/0x280
[  179.182219][ T3731]  do_exit+0xe51/0x3e60
[  179.182930][ T3731]  do_group_exit+0x20e/0x450
[  179.183656][ T3731]  get_signal+0x2dfb/0x38f0
[  179.184344][ T3731]  arch_do_signal_or_restart+0xaa/0xe10
[  179.185266][ T3731]  exit_to_user_mode_prepare+0x2d2/0x560
[  179.186136][ T3731]  syscall_exit_to_user_mode+0x35/0x60
[  179.186984][ T3731]  do_syscall_64+0xc5/0x140
[  179.187681][ T3731]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  179.188604][ T3731] =====================================================

In our case, there are two Thread A and B:

Context: Thread A:              Context: Thread B:

l2cap_chan_timeout()            __se_sys_shutdown()
  l2cap_chan_close()              l2cap_sock_shutdown()
    l2cap_chan_del()                l2cap_chan_close()
      l2cap_sock_teardown_cb()        l2cap_sock_teardown_cb()

Once l2cap_sock_teardown_cb() excuted, this sock will be marked as SOCK_ZAPPED,
and can be treated as killable in l2cap_sock_kill() if sock_orphan() has
excuted, at this time we close sock through sock_close() which end to call
l2cap_sock_kill() like Thread C:

Context: Thread C:

sock_close()
  l2cap_sock_release()
    sock_orphan()
    l2cap_sock_kill()  #free sock if refcnt is 1

If C completed, Once A or B reaches l2cap_sock_teardown_cb() again,
use-after-free happened.

We should set chan-&gt;data to NULL if sock is destructed, for telling teardown
operation is not allowed in l2cap_sock_teardown_cb(), and also we should
avoid killing an already killed socket in l2cap_sock_close_cb().

Signed-off-by: Wang ShaoBo &lt;bobo.shaobowang@huawei.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: sco: Fix lock_sock() blockage by memcpy_from_msg()</title>
<updated>2021-11-17T08:48:27+00:00</updated>
<author>
<name>Takashi Iwai</name>
<email>tiwai@suse.de</email>
</author>
<published>2021-08-28T16:18:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d416020f1a9cc5f903ae66649b2c56d9ad5256ab'/>
<id>d416020f1a9cc5f903ae66649b2c56d9ad5256ab</id>
<content type='text'>
[ Upstream commit 99c23da0eed4fd20cae8243f2b51e10e66aa0951 ]

The sco_send_frame() also takes lock_sock() during memcpy_from_msg()
call that may be endlessly blocked by a task with userfaultd
technique, and this will result in a hung task watchdog trigger.

Just like the similar fix for hci_sock_sendmsg() in commit
92c685dc5de0 ("Bluetooth: reorganize functions..."), this patch moves
the  memcpy_from_msg() out of lock_sock() for addressing the hang.

This should be the last piece for fixing CVE-2021-3640 after a few
already queued fixes.

Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 99c23da0eed4fd20cae8243f2b51e10e66aa0951 ]

The sco_send_frame() also takes lock_sock() during memcpy_from_msg()
call that may be endlessly blocked by a task with userfaultd
technique, and this will result in a hung task watchdog trigger.

Just like the similar fix for hci_sock_sendmsg() in commit
92c685dc5de0 ("Bluetooth: reorganize functions..."), this patch moves
the  memcpy_from_msg() out of lock_sock() for addressing the hang.

This should be the last piece for fixing CVE-2021-3640 after a few
already queued fixes.

Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: Fix handling of LE Enhanced Connection Complete</title>
<updated>2021-09-22T10:26:33+00:00</updated>
<author>
<name>Luiz Augusto von Dentz</name>
<email>luiz.von.dentz@intel.com</email>
</author>
<published>2021-08-11T23:20:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d772d993b0724efae40090a97885401fc45502aa'/>
<id>d772d993b0724efae40090a97885401fc45502aa</id>
<content type='text'>
[ Upstream commit cafae4cd625502f65d1798659c1aa9b62d38cc56 ]

LE Enhanced Connection Complete contains the Local RPA used in the
connection which must be used when set otherwise there could problems
when pairing since the address used by the remote stack could be the
Local RPA:

BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 4, Part E
page 2396

  'Resolvable Private Address being used by the local device for this
  connection. This is only valid when the Own_Address_Type (from the
  HCI_LE_Create_Connection, HCI_LE_Set_Advertising_Parameters,
  HCI_LE_Set_Extended_Advertising_Parameters, or
  HCI_LE_Extended_Create_Connection commands) is set to 0x02 or
  0x03, and the Controller generated a resolvable private address for the
  local device using a non-zero local IRK. For other Own_Address_Type
  values, the Controller shall return all zeros.'

Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit cafae4cd625502f65d1798659c1aa9b62d38cc56 ]

LE Enhanced Connection Complete contains the Local RPA used in the
connection which must be used when set otherwise there could problems
when pairing since the address used by the remote stack could be the
Local RPA:

BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 4, Part E
page 2396

  'Resolvable Private Address being used by the local device for this
  connection. This is only valid when the Own_Address_Type (from the
  HCI_LE_Create_Connection, HCI_LE_Set_Advertising_Parameters,
  HCI_LE_Set_Extended_Advertising_Parameters, or
  HCI_LE_Extended_Create_Connection commands) is set to 0x02 or
  0x03, and the Controller generated a resolvable private address for the
  local device using a non-zero local IRK. For other Own_Address_Type
  values, the Controller shall return all zeros.'

Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Bluetooth: avoid circular locks in sco_sock_connect</title>
<updated>2021-09-22T10:26:32+00:00</updated>
<author>
<name>Desmond Cheong Zhi Xi</name>
<email>desmondcheongzx@gmail.com</email>
</author>
<published>2021-08-10T04:14:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0d563020b8a3b835afa5c902610de700808546ec'/>
<id>0d563020b8a3b835afa5c902610de700808546ec</id>
<content type='text'>
[ Upstream commit 734bc5ff783115aa3164f4e9dd5967ae78e0a8ab ]

In a future patch, calls to bh_lock_sock in sco.c should be replaced
by lock_sock now that none of the functions are run in IRQ context.

However, doing so results in a circular locking dependency:

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc4-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/14867 is trying to acquire lock:
ffff88803e3c1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at:
lock_sock include/net/sock.h:1613 [inline]
ffff88803e3c1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at:
sco_conn_del+0x12a/0x2a0 net/bluetooth/sco.c:191

but task is already holding lock:
ffffffff8d2dc7c8 (hci_cb_list_lock){+.+.}-{3:3}, at:
hci_disconn_cfm include/net/bluetooth/hci_core.h:1497 [inline]
ffffffff8d2dc7c8 (hci_cb_list_lock){+.+.}-{3:3}, at:
hci_conn_hash_flush+0xda/0x260 net/bluetooth/hci_conn.c:1608

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-&gt; #2 (hci_cb_list_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:959 [inline]
       __mutex_lock+0x12a/0x10a0 kernel/locking/mutex.c:1104
       hci_connect_cfm include/net/bluetooth/hci_core.h:1482 [inline]
       hci_remote_features_evt net/bluetooth/hci_event.c:3263 [inline]
       hci_event_packet+0x2f4d/0x7c50 net/bluetooth/hci_event.c:6240
       hci_rx_work+0x4f8/0xd30 net/bluetooth/hci_core.c:5122
       process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
       worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
       kthread+0x3e5/0x4d0 kernel/kthread.c:319
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-&gt; #1 (&amp;hdev-&gt;lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:959 [inline]
       __mutex_lock+0x12a/0x10a0 kernel/locking/mutex.c:1104
       sco_connect net/bluetooth/sco.c:245 [inline]
       sco_sock_connect+0x227/0xa10 net/bluetooth/sco.c:601
       __sys_connect_file+0x155/0x1a0 net/socket.c:1879
       __sys_connect+0x161/0x190 net/socket.c:1896
       __do_sys_connect net/socket.c:1906 [inline]
       __se_sys_connect net/socket.c:1903 [inline]
       __x64_sys_connect+0x6f/0xb0 net/socket.c:1903
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-&gt; #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain kernel/locking/lockdep.c:3789 [inline]
       __lock_acquire+0x2a07/0x54a0 kernel/locking/lockdep.c:5015
       lock_acquire kernel/locking/lockdep.c:5625 [inline]
       lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
       lock_sock_nested+0xca/0x120 net/core/sock.c:3170
       lock_sock include/net/sock.h:1613 [inline]
       sco_conn_del+0x12a/0x2a0 net/bluetooth/sco.c:191
       sco_disconn_cfm+0x71/0xb0 net/bluetooth/sco.c:1202
       hci_disconn_cfm include/net/bluetooth/hci_core.h:1500 [inline]
       hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1608
       hci_dev_do_close+0x528/0x1130 net/bluetooth/hci_core.c:1778
       hci_unregister_dev+0x1c0/0x5a0 net/bluetooth/hci_core.c:4015
       vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:340
       __fput+0x288/0x920 fs/file_table.c:280
       task_work_run+0xdd/0x1a0 kernel/task_work.c:164
       exit_task_work include/linux/task_work.h:32 [inline]
       do_exit+0xbd4/0x2a60 kernel/exit.c:825
       do_group_exit+0x125/0x310 kernel/exit.c:922
       get_signal+0x47f/0x2160 kernel/signal.c:2808
       arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865
       handle_signal_work kernel/entry/common.c:148 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
       exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209
       __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
       syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302
       ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:288

other info that might help us debug this:

Chain exists of:
  sk_lock-AF_BLUETOOTH-BTPROTO_SCO --&gt; &amp;hdev-&gt;lock --&gt; hci_cb_list_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hci_cb_list_lock);
                               lock(&amp;hdev-&gt;lock);
                               lock(hci_cb_list_lock);
  lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO);

 *** DEADLOCK ***

The issue is that the lock hierarchy should go from &amp;hdev-&gt;lock --&gt;
hci_cb_list_lock --&gt; sk_lock-AF_BLUETOOTH-BTPROTO_SCO. For example,
one such call trace is:

  hci_dev_do_close():
    hci_dev_lock();
    hci_conn_hash_flush():
      hci_disconn_cfm():
        mutex_lock(&amp;hci_cb_list_lock);
        sco_disconn_cfm():
        sco_conn_del():
          lock_sock(sk);

However, in sco_sock_connect, we call lock_sock before calling
hci_dev_lock inside sco_connect, thus inverting the lock hierarchy.

We fix this by pulling the call to hci_dev_lock out from sco_connect.

Signed-off-by: Desmond Cheong Zhi Xi &lt;desmondcheongzx@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 734bc5ff783115aa3164f4e9dd5967ae78e0a8ab ]

In a future patch, calls to bh_lock_sock in sco.c should be replaced
by lock_sock now that none of the functions are run in IRQ context.

However, doing so results in a circular locking dependency:

======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc4-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/14867 is trying to acquire lock:
ffff88803e3c1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at:
lock_sock include/net/sock.h:1613 [inline]
ffff88803e3c1120 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}, at:
sco_conn_del+0x12a/0x2a0 net/bluetooth/sco.c:191

but task is already holding lock:
ffffffff8d2dc7c8 (hci_cb_list_lock){+.+.}-{3:3}, at:
hci_disconn_cfm include/net/bluetooth/hci_core.h:1497 [inline]
ffffffff8d2dc7c8 (hci_cb_list_lock){+.+.}-{3:3}, at:
hci_conn_hash_flush+0xda/0x260 net/bluetooth/hci_conn.c:1608

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-&gt; #2 (hci_cb_list_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:959 [inline]
       __mutex_lock+0x12a/0x10a0 kernel/locking/mutex.c:1104
       hci_connect_cfm include/net/bluetooth/hci_core.h:1482 [inline]
       hci_remote_features_evt net/bluetooth/hci_event.c:3263 [inline]
       hci_event_packet+0x2f4d/0x7c50 net/bluetooth/hci_event.c:6240
       hci_rx_work+0x4f8/0xd30 net/bluetooth/hci_core.c:5122
       process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
       worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
       kthread+0x3e5/0x4d0 kernel/kthread.c:319
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-&gt; #1 (&amp;hdev-&gt;lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:959 [inline]
       __mutex_lock+0x12a/0x10a0 kernel/locking/mutex.c:1104
       sco_connect net/bluetooth/sco.c:245 [inline]
       sco_sock_connect+0x227/0xa10 net/bluetooth/sco.c:601
       __sys_connect_file+0x155/0x1a0 net/socket.c:1879
       __sys_connect+0x161/0x190 net/socket.c:1896
       __do_sys_connect net/socket.c:1906 [inline]
       __se_sys_connect net/socket.c:1903 [inline]
       __x64_sys_connect+0x6f/0xb0 net/socket.c:1903
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-&gt; #0 (sk_lock-AF_BLUETOOTH-BTPROTO_SCO){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain kernel/locking/lockdep.c:3789 [inline]
       __lock_acquire+0x2a07/0x54a0 kernel/locking/lockdep.c:5015
       lock_acquire kernel/locking/lockdep.c:5625 [inline]
       lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
       lock_sock_nested+0xca/0x120 net/core/sock.c:3170
       lock_sock include/net/sock.h:1613 [inline]
       sco_conn_del+0x12a/0x2a0 net/bluetooth/sco.c:191
       sco_disconn_cfm+0x71/0xb0 net/bluetooth/sco.c:1202
       hci_disconn_cfm include/net/bluetooth/hci_core.h:1500 [inline]
       hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1608
       hci_dev_do_close+0x528/0x1130 net/bluetooth/hci_core.c:1778
       hci_unregister_dev+0x1c0/0x5a0 net/bluetooth/hci_core.c:4015
       vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:340
       __fput+0x288/0x920 fs/file_table.c:280
       task_work_run+0xdd/0x1a0 kernel/task_work.c:164
       exit_task_work include/linux/task_work.h:32 [inline]
       do_exit+0xbd4/0x2a60 kernel/exit.c:825
       do_group_exit+0x125/0x310 kernel/exit.c:922
       get_signal+0x47f/0x2160 kernel/signal.c:2808
       arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865
       handle_signal_work kernel/entry/common.c:148 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
       exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209
       __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
       syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302
       ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:288

other info that might help us debug this:

Chain exists of:
  sk_lock-AF_BLUETOOTH-BTPROTO_SCO --&gt; &amp;hdev-&gt;lock --&gt; hci_cb_list_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hci_cb_list_lock);
                               lock(&amp;hdev-&gt;lock);
                               lock(hci_cb_list_lock);
  lock(sk_lock-AF_BLUETOOTH-BTPROTO_SCO);

 *** DEADLOCK ***

The issue is that the lock hierarchy should go from &amp;hdev-&gt;lock --&gt;
hci_cb_list_lock --&gt; sk_lock-AF_BLUETOOTH-BTPROTO_SCO. For example,
one such call trace is:

  hci_dev_do_close():
    hci_dev_lock();
    hci_conn_hash_flush():
      hci_disconn_cfm():
        mutex_lock(&amp;hci_cb_list_lock);
        sco_disconn_cfm():
        sco_conn_del():
          lock_sock(sk);

However, in sco_sock_connect, we call lock_sock before calling
hci_dev_lock inside sco_connect, thus inverting the lock hierarchy.

We fix this by pulling the call to hci_dev_lock out from sco_connect.

Signed-off-by: Desmond Cheong Zhi Xi &lt;desmondcheongzx@gmail.com&gt;
Signed-off-by: Luiz Augusto von Dentz &lt;luiz.von.dentz@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
