linux.git/net/bluetooth, branch v6.9 Linux kernel source tree Bluetooth: l2cap: fix null-ptr-deref in l2cap_chan_timeout 2024-05-03T17:05:54+00:00 Duoming Zhou duoming@zju.edu.cn 2024-05-02T12:57:36+00:00 adf0398cee86643b8eacde95f17d073d022f782c There is a race condition between l2cap_chan_timeout() and l2cap_chan_del(). When we use l2cap_chan_del() to delete the channel, the chan->conn will be set to null. But the conn could be dereferenced again in the mutex_lock() of l2cap_chan_timeout(). As a result the null pointer dereference bug will happen. The KASAN report triggered by POC is shown below: [ 472.074580] ================================================================== [ 472.075284] BUG: KASAN: null-ptr-deref in mutex_lock+0x68/0xc0 [ 472.075308] Write of size 8 at addr 0000000000000158 by task kworker/0:0/7 [ 472.075308] [ 472.075308] CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.9.0-rc5-00356-g78c0094a146b #36 [ 472.075308] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4 [ 472.075308] Workqueue: events l2cap_chan_timeout [ 472.075308] Call Trace: [ 472.075308] <TASK> [ 472.075308] dump_stack_lvl+0x137/0x1a0 [ 472.075308] print_report+0x101/0x250 [ 472.075308] ? __virt_addr_valid+0x77/0x160 [ 472.075308] ? mutex_lock+0x68/0xc0 [ 472.075308] kasan_report+0x139/0x170 [ 472.075308] ? mutex_lock+0x68/0xc0 [ 472.075308] kasan_check_range+0x2c3/0x2e0 [ 472.075308] mutex_lock+0x68/0xc0 [ 472.075308] l2cap_chan_timeout+0x181/0x300 [ 472.075308] process_one_work+0x5d2/0xe00 [ 472.075308] worker_thread+0xe1d/0x1660 [ 472.075308] ? pr_cont_work+0x5e0/0x5e0 [ 472.075308] kthread+0x2b7/0x350 [ 472.075308] ? pr_cont_work+0x5e0/0x5e0 [ 472.075308] ? kthread_blkcg+0xd0/0xd0 [ 472.075308] ret_from_fork+0x4d/0x80 [ 472.075308] ? kthread_blkcg+0xd0/0xd0 [ 472.075308] ret_from_fork_asm+0x11/0x20 [ 472.075308] </TASK> [ 472.075308] ================================================================== [ 472.094860] Disabling lock debugging due to kernel taint [ 472.096136] BUG: kernel NULL pointer dereference, address: 0000000000000158 [ 472.096136] #PF: supervisor write access in kernel mode [ 472.096136] #PF: error_code(0x0002) - not-present page [ 472.096136] PGD 0 P4D 0 [ 472.096136] Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI [ 472.096136] CPU: 0 PID: 7 Comm: kworker/0:0 Tainted: G B 6.9.0-rc5-00356-g78c0094a146b #36 [ 472.096136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4 [ 472.096136] Workqueue: events l2cap_chan_timeout [ 472.096136] RIP: 0010:mutex_lock+0x88/0xc0 [ 472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88 [ 472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246 [ 472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865 [ 472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78 [ 472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f [ 472.096136] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000 [ 472.096136] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00 [ 472.096136] FS: 0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000 [ 472.096136] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 472.096136] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0 [ 472.096136] Call Trace: [ 472.096136] <TASK> [ 472.096136] ? __die_body+0x8d/0xe0 [ 472.096136] ? page_fault_oops+0x6b8/0x9a0 [ 472.096136] ? kernelmode_fixup_or_oops+0x20c/0x2a0 [ 472.096136] ? do_user_addr_fault+0x1027/0x1340 [ 472.096136] ? _printk+0x7a/0xa0 [ 472.096136] ? mutex_lock+0x68/0xc0 [ 472.096136] ? add_taint+0x42/0xd0 [ 472.096136] ? exc_page_fault+0x6a/0x1b0 [ 472.096136] ? asm_exc_page_fault+0x26/0x30 [ 472.096136] ? mutex_lock+0x75/0xc0 [ 472.096136] ? mutex_lock+0x88/0xc0 [ 472.096136] ? mutex_lock+0x75/0xc0 [ 472.096136] l2cap_chan_timeout+0x181/0x300 [ 472.096136] process_one_work+0x5d2/0xe00 [ 472.096136] worker_thread+0xe1d/0x1660 [ 472.096136] ? pr_cont_work+0x5e0/0x5e0 [ 472.096136] kthread+0x2b7/0x350 [ 472.096136] ? pr_cont_work+0x5e0/0x5e0 [ 472.096136] ? kthread_blkcg+0xd0/0xd0 [ 472.096136] ret_from_fork+0x4d/0x80 [ 472.096136] ? kthread_blkcg+0xd0/0xd0 [ 472.096136] ret_from_fork_asm+0x11/0x20 [ 472.096136] </TASK> [ 472.096136] Modules linked in: [ 472.096136] CR2: 0000000000000158 [ 472.096136] ---[ end trace 0000000000000000 ]--- [ 472.096136] RIP: 0010:mutex_lock+0x88/0xc0 [ 472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88 [ 472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246 [ 472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865 [ 472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78 [ 472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f [ 472.132932] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000 [ 472.132932] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00 [ 472.132932] FS: 0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000 [ 472.132932] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 472.132932] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0 [ 472.132932] Kernel panic - not syncing: Fatal exception [ 472.132932] Kernel Offset: disabled [ 472.132932] ---[ end Kernel panic - not syncing: Fatal exception ]--- Add a check to judge whether the conn is null in l2cap_chan_timeout() in order to mitigate the bug. Fixes: 3df91ea20e74 ("Bluetooth: Revert to mutexes from RCU list") Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
There is a race condition between l2cap_chan_timeout() and
l2cap_chan_del(). When we use l2cap_chan_del() to delete the
channel, the chan->conn will be set to null. But the conn could
be dereferenced again in the mutex_lock() of l2cap_chan_timeout().
As a result the null pointer dereference bug will happen. The
KASAN report triggered by POC is shown below:

[  472.074580] ==================================================================
[  472.075284] BUG: KASAN: null-ptr-deref in mutex_lock+0x68/0xc0
[  472.075308] Write of size 8 at addr 0000000000000158 by task kworker/0:0/7
[  472.075308]
[  472.075308] CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.9.0-rc5-00356-g78c0094a146b #36
[  472.075308] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4
[  472.075308] Workqueue: events l2cap_chan_timeout
[  472.075308] Call Trace:
[  472.075308]  <TASK>
[  472.075308]  dump_stack_lvl+0x137/0x1a0
[  472.075308]  print_report+0x101/0x250
[  472.075308]  ? __virt_addr_valid+0x77/0x160
[  472.075308]  ? mutex_lock+0x68/0xc0
[  472.075308]  kasan_report+0x139/0x170
[  472.075308]  ? mutex_lock+0x68/0xc0
[  472.075308]  kasan_check_range+0x2c3/0x2e0
[  472.075308]  mutex_lock+0x68/0xc0
[  472.075308]  l2cap_chan_timeout+0x181/0x300
[  472.075308]  process_one_work+0x5d2/0xe00
[  472.075308]  worker_thread+0xe1d/0x1660
[  472.075308]  ? pr_cont_work+0x5e0/0x5e0
[  472.075308]  kthread+0x2b7/0x350
[  472.075308]  ? pr_cont_work+0x5e0/0x5e0
[  472.075308]  ? kthread_blkcg+0xd0/0xd0
[  472.075308]  ret_from_fork+0x4d/0x80
[  472.075308]  ? kthread_blkcg+0xd0/0xd0
[  472.075308]  ret_from_fork_asm+0x11/0x20
[  472.075308]  </TASK>
[  472.075308] ==================================================================
[  472.094860] Disabling lock debugging due to kernel taint
[  472.096136] BUG: kernel NULL pointer dereference, address: 0000000000000158
[  472.096136] #PF: supervisor write access in kernel mode
[  472.096136] #PF: error_code(0x0002) - not-present page
[  472.096136] PGD 0 P4D 0
[  472.096136] Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI
[  472.096136] CPU: 0 PID: 7 Comm: kworker/0:0 Tainted: G    B              6.9.0-rc5-00356-g78c0094a146b #36
[  472.096136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu4
[  472.096136] Workqueue: events l2cap_chan_timeout
[  472.096136] RIP: 0010:mutex_lock+0x88/0xc0
[  472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88
[  472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246
[  472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865
[  472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78
[  472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f
[  472.096136] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000
[  472.096136] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00
[  472.096136] FS:  0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000
[  472.096136] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  472.096136] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0
[  472.096136] Call Trace:
[  472.096136]  <TASK>
[  472.096136]  ? __die_body+0x8d/0xe0
[  472.096136]  ? page_fault_oops+0x6b8/0x9a0
[  472.096136]  ? kernelmode_fixup_or_oops+0x20c/0x2a0
[  472.096136]  ? do_user_addr_fault+0x1027/0x1340
[  472.096136]  ? _printk+0x7a/0xa0
[  472.096136]  ? mutex_lock+0x68/0xc0
[  472.096136]  ? add_taint+0x42/0xd0
[  472.096136]  ? exc_page_fault+0x6a/0x1b0
[  472.096136]  ? asm_exc_page_fault+0x26/0x30
[  472.096136]  ? mutex_lock+0x75/0xc0
[  472.096136]  ? mutex_lock+0x88/0xc0
[  472.096136]  ? mutex_lock+0x75/0xc0
[  472.096136]  l2cap_chan_timeout+0x181/0x300
[  472.096136]  process_one_work+0x5d2/0xe00
[  472.096136]  worker_thread+0xe1d/0x1660
[  472.096136]  ? pr_cont_work+0x5e0/0x5e0
[  472.096136]  kthread+0x2b7/0x350
[  472.096136]  ? pr_cont_work+0x5e0/0x5e0
[  472.096136]  ? kthread_blkcg+0xd0/0xd0
[  472.096136]  ret_from_fork+0x4d/0x80
[  472.096136]  ? kthread_blkcg+0xd0/0xd0
[  472.096136]  ret_from_fork_asm+0x11/0x20
[  472.096136]  </TASK>
[  472.096136] Modules linked in:
[  472.096136] CR2: 0000000000000158
[  472.096136] ---[ end trace 0000000000000000 ]---
[  472.096136] RIP: 0010:mutex_lock+0x88/0xc0
[  472.096136] Code: be 08 00 00 00 e8 f8 23 1f fd 4c 89 f7 be 08 00 00 00 e8 eb 23 1f fd 42 80 3c 23 00 74 08 48 88
[  472.096136] RSP: 0018:ffff88800744fc78 EFLAGS: 00000246
[  472.096136] RAX: 0000000000000000 RBX: 1ffff11000e89f8f RCX: ffffffff8457c865
[  472.096136] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88800744fc78
[  472.096136] RBP: 0000000000000158 R08: ffff88800744fc7f R09: 1ffff11000e89f8f
[  472.132932] R10: dffffc0000000000 R11: ffffed1000e89f90 R12: dffffc0000000000
[  472.132932] R13: 0000000000000158 R14: ffff88800744fc78 R15: ffff888007405a00
[  472.132932] FS:  0000000000000000(0000) GS:ffff88806d200000(0000) knlGS:0000000000000000
[  472.132932] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  472.132932] CR2: 0000000000000158 CR3: 000000000da32000 CR4: 00000000000006f0
[  472.132932] Kernel panic - not syncing: Fatal exception
[  472.132932] Kernel Offset: disabled
[  472.132932] ---[ end Kernel panic - not syncing: Fatal exception ]---

Add a check to judge whether the conn is null in l2cap_chan_timeout()
in order to mitigate the bug.

Fixes: 3df91ea20e74 ("Bluetooth: Revert to mutexes from RCU list")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: HCI: Fix potential null-ptr-deref 2024-05-03T17:05:53+00:00 Sungwoo Kim iam@sung-woo.kim 2024-05-02T16:09:31+00:00 d2706004a1b8b526592e823d7e52551b518a7941 Fix potential null-ptr-deref in hci_le_big_sync_established_evt(). Fixes: f777d8827817 (Bluetooth: ISO: Notify user space about failed bis connections) Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Fix potential null-ptr-deref in hci_le_big_sync_established_evt().

Fixes: f777d8827817 (Bluetooth: ISO: Notify user space about failed bis connections)
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: msft: fix slab-use-after-free in msft_do_close() 2024-05-03T17:05:28+00:00 Sungwoo Kim iam@sung-woo.kim 2024-04-30T16:20:51+00:00 10f9f426ac6e752c8d87bf4346930ba347aaabac Tying the msft->data lifetime to hdev by freeing it in hci_release_dev() to fix the following case: [use] msft_do_close() msft = hdev->msft_data; if (!msft) ...(1) <- passed. return; mutex_lock(&msft->filter_lock); ...(4) <- used after freed. [free] msft_unregister() msft = hdev->msft_data; hdev->msft_data = NULL; ...(2) kfree(msft); ...(3) <- msft is freed. ================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:587 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f/0xc30 kernel/locking/mutex.c:752 Read of size 8 at addr ffff888106cbbca8 by task kworker/u5:2/309 Fixes: bf6a4e30ffbd ("Bluetooth: disable advertisement filters during suspend") Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Tying the msft->data lifetime to hdev by freeing it in
hci_release_dev() to fix the following case:

[use]
msft_do_close()
  msft = hdev->msft_data;
  if (!msft)                      ...(1) <- passed.
    return;
  mutex_lock(&msft->filter_lock); ...(4) <- used after freed.

[free]
msft_unregister()
  msft = hdev->msft_data;
  hdev->msft_data = NULL;         ...(2)
  kfree(msft);                    ...(3) <- msft is freed.

==================================================================
BUG: KASAN: slab-use-after-free in __mutex_lock_common
kernel/locking/mutex.c:587 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f/0xc30
kernel/locking/mutex.c:752
Read of size 8 at addr ffff888106cbbca8 by task kworker/u5:2/309

Fixes: bf6a4e30ffbd ("Bluetooth: disable advertisement filters during suspend")
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: L2CAP: Fix slab-use-after-free in l2cap_connect() 2024-05-03T17:05:26+00:00 Sungwoo Kim iam@sung-woo.kim 2024-04-30T06:32:10+00:00 4d7b41c0e43995b0e992b9f8903109275744b658 Extend a critical section to prevent chan from early freeing. Also make the l2cap_connect() return type void. Nothing is using the returned value but it is ugly to return a potentially freed pointer. Making it void will help with backports because earlier kernels did use the return value. Now the compile will break for kernels where this patch is not a complete fix. Call stack summary: [use] l2cap_bredr_sig_cmd l2cap_connect ┌ mutex_lock(&conn->chan_lock); │ chan = pchan->ops->new_connection(pchan); <- alloc chan │ __l2cap_chan_add(conn, chan); │ l2cap_chan_hold(chan); │ list_add(&chan->list, &conn->chan_l); ... (1) └ mutex_unlock(&conn->chan_lock); chan->conf_state ... (4) <- use after free [free] l2cap_conn_del ┌ mutex_lock(&conn->chan_lock); │ foreach chan in conn->chan_l: ... (2) │ l2cap_chan_put(chan); │ l2cap_chan_destroy │ kfree(chan) ... (3) <- chan freed └ mutex_unlock(&conn->chan_lock); ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect+0xa67/0x11a0 net/bluetooth/l2cap_core.c:4260 Read of size 8 at addr ffff88810bf040a0 by task kworker/u3:1/311 Fixes: 73ffa904b782 ("Bluetooth: Move conf_{req,rsp} stuff to struct l2cap_chan") Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Extend a critical section to prevent chan from early freeing.
Also make the l2cap_connect() return type void. Nothing is using the
returned value but it is ugly to return a potentially freed pointer.
Making it void will help with backports because earlier kernels did use
the return value. Now the compile will break for kernels where this
patch is not a complete fix.

Call stack summary:

[use]
l2cap_bredr_sig_cmd
  l2cap_connect
  ┌ mutex_lock(&conn->chan_lock);
  │ chan = pchan->ops->new_connection(pchan); <- alloc chan
  │ __l2cap_chan_add(conn, chan);
  │   l2cap_chan_hold(chan);
  │   list_add(&chan->list, &conn->chan_l);   ... (1)
  └ mutex_unlock(&conn->chan_lock);
    chan->conf_state              ... (4) <- use after free

[free]
l2cap_conn_del
┌ mutex_lock(&conn->chan_lock);
│ foreach chan in conn->chan_l:            ... (2)
│   l2cap_chan_put(chan);
│     l2cap_chan_destroy
│       kfree(chan)               ... (3) <- chan freed
└ mutex_unlock(&conn->chan_lock);

==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read
include/linux/instrumented.h:68 [inline]
BUG: KASAN: slab-use-after-free in _test_bit
include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect+0xa67/0x11a0
net/bluetooth/l2cap_core.c:4260
Read of size 8 at addr ffff88810bf040a0 by task kworker/u3:1/311

Fixes: 73ffa904b782 ("Bluetooth: Move conf_{req,rsp} stuff to struct l2cap_chan")
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: Fix use-after-free bugs caused by sco_sock_timeout 2024-05-03T17:03:53+00:00 Duoming Zhou duoming@zju.edu.cn 2024-04-25T14:23:45+00:00 483bc08181827fc475643272ffb69c533007e546 When the sco connection is established and then, the sco socket is releasing, timeout_work will be scheduled to judge whether the sco disconnection is timeout. The sock will be deallocated later, but it is dereferenced again in sco_sock_timeout. As a result, the use-after-free bugs will happen. The root cause is shown below: Cleanup Thread | Worker Thread sco_sock_release | sco_sock_close | __sco_sock_close | sco_sock_set_timer | schedule_delayed_work | sco_sock_kill | (wait a time) sock_put(sk) //FREE | sco_sock_timeout | sock_hold(sk) //USE The KASAN report triggered by POC is shown below: [ 95.890016] ================================================================== [ 95.890496] BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x5e/0x1c0 [ 95.890755] Write of size 4 at addr ffff88800c388080 by task kworker/0:0/7 ... [ 95.890755] Workqueue: events sco_sock_timeout [ 95.890755] Call Trace: [ 95.890755] <TASK> [ 95.890755] dump_stack_lvl+0x45/0x110 [ 95.890755] print_address_description+0x78/0x390 [ 95.890755] print_report+0x11b/0x250 [ 95.890755] ? __virt_addr_valid+0xbe/0xf0 [ 95.890755] ? sco_sock_timeout+0x5e/0x1c0 [ 95.890755] kasan_report+0x139/0x170 [ 95.890755] ? update_load_avg+0xe5/0x9f0 [ 95.890755] ? sco_sock_timeout+0x5e/0x1c0 [ 95.890755] kasan_check_range+0x2c3/0x2e0 [ 95.890755] sco_sock_timeout+0x5e/0x1c0 [ 95.890755] process_one_work+0x561/0xc50 [ 95.890755] worker_thread+0xab2/0x13c0 [ 95.890755] ? pr_cont_work+0x490/0x490 [ 95.890755] kthread+0x279/0x300 [ 95.890755] ? pr_cont_work+0x490/0x490 [ 95.890755] ? kthread_blkcg+0xa0/0xa0 [ 95.890755] ret_from_fork+0x34/0x60 [ 95.890755] ? kthread_blkcg+0xa0/0xa0 [ 95.890755] ret_from_fork_asm+0x11/0x20 [ 95.890755] </TASK> [ 95.890755] [ 95.890755] Allocated by task 506: [ 95.890755] kasan_save_track+0x3f/0x70 [ 95.890755] __kasan_kmalloc+0x86/0x90 [ 95.890755] __kmalloc+0x17f/0x360 [ 95.890755] sk_prot_alloc+0xe1/0x1a0 [ 95.890755] sk_alloc+0x31/0x4e0 [ 95.890755] bt_sock_alloc+0x2b/0x2a0 [ 95.890755] sco_sock_create+0xad/0x320 [ 95.890755] bt_sock_create+0x145/0x320 [ 95.890755] __sock_create+0x2e1/0x650 [ 95.890755] __sys_socket+0xd0/0x280 [ 95.890755] __x64_sys_socket+0x75/0x80 [ 95.890755] do_syscall_64+0xc4/0x1b0 [ 95.890755] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 95.890755] [ 95.890755] Freed by task 506: [ 95.890755] kasan_save_track+0x3f/0x70 [ 95.890755] kasan_save_free_info+0x40/0x50 [ 95.890755] poison_slab_object+0x118/0x180 [ 95.890755] __kasan_slab_free+0x12/0x30 [ 95.890755] kfree+0xb2/0x240 [ 95.890755] __sk_destruct+0x317/0x410 [ 95.890755] sco_sock_release+0x232/0x280 [ 95.890755] sock_close+0xb2/0x210 [ 95.890755] __fput+0x37f/0x770 [ 95.890755] task_work_run+0x1ae/0x210 [ 95.890755] get_signal+0xe17/0xf70 [ 95.890755] arch_do_signal_or_restart+0x3f/0x520 [ 95.890755] syscall_exit_to_user_mode+0x55/0x120 [ 95.890755] do_syscall_64+0xd1/0x1b0 [ 95.890755] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 95.890755] [ 95.890755] The buggy address belongs to the object at ffff88800c388000 [ 95.890755] which belongs to the cache kmalloc-1k of size 1024 [ 95.890755] The buggy address is located 128 bytes inside of [ 95.890755] freed 1024-byte region [ffff88800c388000, ffff88800c388400) [ 95.890755] [ 95.890755] The buggy address belongs to the physical page: [ 95.890755] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88800c38a800 pfn:0xc388 [ 95.890755] head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 95.890755] anon flags: 0x100000000000840(slab|head|node=0|zone=1) [ 95.890755] page_type: 0xffffffff() [ 95.890755] raw: 0100000000000840 ffff888006842dc0 0000000000000000 0000000000000001 [ 95.890755] raw: ffff88800c38a800 000000000010000a 00000001ffffffff 0000000000000000 [ 95.890755] head: 0100000000000840 ffff888006842dc0 0000000000000000 0000000000000001 [ 95.890755] head: ffff88800c38a800 000000000010000a 00000001ffffffff 0000000000000000 [ 95.890755] head: 0100000000000003 ffffea000030e201 ffffea000030e248 00000000ffffffff [ 95.890755] head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000 [ 95.890755] page dumped because: kasan: bad access detected [ 95.890755] [ 95.890755] Memory state around the buggy address: [ 95.890755] ffff88800c387f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 95.890755] ffff88800c388000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.890755] >ffff88800c388080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.890755] ^ [ 95.890755] ffff88800c388100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.890755] ffff88800c388180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.890755] ================================================================== Fix this problem by adding a check protected by sco_conn_lock to judget whether the conn->hcon is null. Because the conn->hcon will be set to null, when the sock is releasing. Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work") Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
When the sco connection is established and then, the sco socket
is releasing, timeout_work will be scheduled to judge whether
the sco disconnection is timeout. The sock will be deallocated
later, but it is dereferenced again in sco_sock_timeout. As a
result, the use-after-free bugs will happen. The root cause is
shown below:

    Cleanup Thread               |      Worker Thread
sco_sock_release                 |
  sco_sock_close                 |
    __sco_sock_close             |
      sco_sock_set_timer         |
        schedule_delayed_work    |
  sco_sock_kill                  |    (wait a time)
    sock_put(sk) //FREE          |  sco_sock_timeout
                                 |    sock_hold(sk) //USE

The KASAN report triggered by POC is shown below:

[   95.890016] ==================================================================
[   95.890496] BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x5e/0x1c0
[   95.890755] Write of size 4 at addr ffff88800c388080 by task kworker/0:0/7
...
[   95.890755] Workqueue: events sco_sock_timeout
[   95.890755] Call Trace:
[   95.890755]  <TASK>
[   95.890755]  dump_stack_lvl+0x45/0x110
[   95.890755]  print_address_description+0x78/0x390
[   95.890755]  print_report+0x11b/0x250
[   95.890755]  ? __virt_addr_valid+0xbe/0xf0
[   95.890755]  ? sco_sock_timeout+0x5e/0x1c0
[   95.890755]  kasan_report+0x139/0x170
[   95.890755]  ? update_load_avg+0xe5/0x9f0
[   95.890755]  ? sco_sock_timeout+0x5e/0x1c0
[   95.890755]  kasan_check_range+0x2c3/0x2e0
[   95.890755]  sco_sock_timeout+0x5e/0x1c0
[   95.890755]  process_one_work+0x561/0xc50
[   95.890755]  worker_thread+0xab2/0x13c0
[   95.890755]  ? pr_cont_work+0x490/0x490
[   95.890755]  kthread+0x279/0x300
[   95.890755]  ? pr_cont_work+0x490/0x490
[   95.890755]  ? kthread_blkcg+0xa0/0xa0
[   95.890755]  ret_from_fork+0x34/0x60
[   95.890755]  ? kthread_blkcg+0xa0/0xa0
[   95.890755]  ret_from_fork_asm+0x11/0x20
[   95.890755]  </TASK>
[   95.890755]
[   95.890755] Allocated by task 506:
[   95.890755]  kasan_save_track+0x3f/0x70
[   95.890755]  __kasan_kmalloc+0x86/0x90
[   95.890755]  __kmalloc+0x17f/0x360
[   95.890755]  sk_prot_alloc+0xe1/0x1a0
[   95.890755]  sk_alloc+0x31/0x4e0
[   95.890755]  bt_sock_alloc+0x2b/0x2a0
[   95.890755]  sco_sock_create+0xad/0x320
[   95.890755]  bt_sock_create+0x145/0x320
[   95.890755]  __sock_create+0x2e1/0x650
[   95.890755]  __sys_socket+0xd0/0x280
[   95.890755]  __x64_sys_socket+0x75/0x80
[   95.890755]  do_syscall_64+0xc4/0x1b0
[   95.890755]  entry_SYSCALL_64_after_hwframe+0x67/0x6f
[   95.890755]
[   95.890755] Freed by task 506:
[   95.890755]  kasan_save_track+0x3f/0x70
[   95.890755]  kasan_save_free_info+0x40/0x50
[   95.890755]  poison_slab_object+0x118/0x180
[   95.890755]  __kasan_slab_free+0x12/0x30
[   95.890755]  kfree+0xb2/0x240
[   95.890755]  __sk_destruct+0x317/0x410
[   95.890755]  sco_sock_release+0x232/0x280
[   95.890755]  sock_close+0xb2/0x210
[   95.890755]  __fput+0x37f/0x770
[   95.890755]  task_work_run+0x1ae/0x210
[   95.890755]  get_signal+0xe17/0xf70
[   95.890755]  arch_do_signal_or_restart+0x3f/0x520
[   95.890755]  syscall_exit_to_user_mode+0x55/0x120
[   95.890755]  do_syscall_64+0xd1/0x1b0
[   95.890755]  entry_SYSCALL_64_after_hwframe+0x67/0x6f
[   95.890755]
[   95.890755] The buggy address belongs to the object at ffff88800c388000
[   95.890755]  which belongs to the cache kmalloc-1k of size 1024
[   95.890755] The buggy address is located 128 bytes inside of
[   95.890755]  freed 1024-byte region [ffff88800c388000, ffff88800c388400)
[   95.890755]
[   95.890755] The buggy address belongs to the physical page:
[   95.890755] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88800c38a800 pfn:0xc388
[   95.890755] head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
[   95.890755] anon flags: 0x100000000000840(slab|head|node=0|zone=1)
[   95.890755] page_type: 0xffffffff()
[   95.890755] raw: 0100000000000840 ffff888006842dc0 0000000000000000 0000000000000001
[   95.890755] raw: ffff88800c38a800 000000000010000a 00000001ffffffff 0000000000000000
[   95.890755] head: 0100000000000840 ffff888006842dc0 0000000000000000 0000000000000001
[   95.890755] head: ffff88800c38a800 000000000010000a 00000001ffffffff 0000000000000000
[   95.890755] head: 0100000000000003 ffffea000030e201 ffffea000030e248 00000000ffffffff
[   95.890755] head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000
[   95.890755] page dumped because: kasan: bad access detected
[   95.890755]
[   95.890755] Memory state around the buggy address:
[   95.890755]  ffff88800c387f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   95.890755]  ffff88800c388000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   95.890755] >ffff88800c388080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   95.890755]                    ^
[   95.890755]  ffff88800c388100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   95.890755]  ffff88800c388180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   95.890755] ==================================================================

Fix this problem by adding a check protected by sco_conn_lock to judget
whether the conn->hcon is null. Because the conn->hcon will be set to null,
when the sock is releasing.

Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: hci_sync: Using hci_cmd_sync_submit when removing Adv Monitor 2024-04-24T20:26:20+00:00 Chun-Yi Lee jlee@suse.com 2024-04-24T13:59:03+00:00 88cd6e6b2d327faa13e4505b07f1e380e51b21ff Since the d883a4669a1de be introduced in v6.4, bluetooth daemon got the following failed message of MGMT_OP_REMOVE_ADV_MONITOR command when controller is power-off: bluetoothd[20976]: src/adapter.c:reset_adv_monitors_complete() Failed to reset Adv Monitors: Failed> Normally this situation is happened when the bluetoothd deamon be started manually after system booting. Which means that bluetoothd received MGMT_EV_INDEX_ADDED event after kernel runs hci_power_off(). Base on doc/mgmt-api.txt, the MGMT_OP_REMOVE_ADV_MONITOR command can be used when the controller is not powered. This patch changes the code in remove_adv_monitor() to use hci_cmd_sync_submit() instead of hci_cmd_sync_queue(). Fixes: d883a4669a1de ("Bluetooth: hci_sync: Only allow hci_cmd_sync_queue if running") Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Cc: Manish Mandlik <mmandlik@google.com> Cc: Archie Pusaka <apusaka@chromium.org> Cc: Miao-chen Chou <mcchou@chromium.org> Signed-off-by: Chun-Yi Lee <jlee@suse.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Since the d883a4669a1de be introduced in v6.4, bluetooth daemon
got the following failed message of MGMT_OP_REMOVE_ADV_MONITOR
command when controller is power-off:

bluetoothd[20976]:
src/adapter.c:reset_adv_monitors_complete() Failed to reset Adv
Monitors: Failed>

Normally this situation is happened when the bluetoothd deamon
be started manually after system booting. Which means that
bluetoothd received MGMT_EV_INDEX_ADDED event after kernel
runs hci_power_off().

Base on doc/mgmt-api.txt, the MGMT_OP_REMOVE_ADV_MONITOR command
can be used when the controller is not powered. This patch changes
the code in remove_adv_monitor() to use hci_cmd_sync_submit()
instead of hci_cmd_sync_queue().

Fixes: d883a4669a1de ("Bluetooth: hci_sync: Only allow hci_cmd_sync_queue if running")
Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Manish Mandlik <mmandlik@google.com>
Cc: Archie Pusaka <apusaka@chromium.org>
Cc: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Chun-Yi Lee <jlee@suse.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: MGMT: Fix failing to MGMT_OP_ADD_UUID/MGMT_OP_REMOVE_UUID 2024-04-24T20:26:14+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2024-04-16T19:34:45+00:00 6eb5fcc416f127f220b9177a5c9ae751cac1cda8 These commands don't require the adapter to be up and running so don't use hci_cmd_sync_queue which would check that flag, instead use hci_cmd_sync_submit which would ensure mgmt_class_complete is set properly regardless if any command was actually run or not. Link: https://github.com/bluez/bluez/issues/809 Fixes: d883a4669a1d ("Bluetooth: hci_sync: Only allow hci_cmd_sync_queue if running") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
These commands don't require the adapter to be up and running so don't
use hci_cmd_sync_queue which would check that flag, instead use
hci_cmd_sync_submit which would ensure mgmt_class_complete is set
properly regardless if any command was actually run or not.

Link: https://github.com/bluez/bluez/issues/809
Fixes: d883a4669a1d ("Bluetooth: hci_sync: Only allow hci_cmd_sync_queue if running")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: hci_event: Fix sending HCI_OP_READ_ENC_KEY_SIZE 2024-04-24T20:26:11+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2024-04-15T17:41:01+00:00 a9a830a676a9a93c5020f5c61236166931fa4266 The code shall always check if HCI_QUIRK_BROKEN_READ_ENC_KEY_SIZE has been set before attempting to use HCI_OP_READ_ENC_KEY_SIZE. Fixes: c569242cd492 ("Bluetooth: hci_event: set the conn encrypted before conn establishes") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
The code shall always check if HCI_QUIRK_BROKEN_READ_ENC_KEY_SIZE has
been set before attempting to use HCI_OP_READ_ENC_KEY_SIZE.

Fixes: c569242cd492 ("Bluetooth: hci_event: set the conn encrypted before conn establishes")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: hci_sync: Use advertised PHYs on hci_le_ext_create_conn_sync 2024-04-24T20:26:08+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2024-04-05T20:40:33+00:00 2e7ed5f5e69b6fe93dd3c6b651d041e0a7a456d1 The extended advertising reports do report the PHYs so this store then in hci_conn so it can be later used in hci_le_ext_create_conn_sync to narrow the PHYs to be scanned since the controller will also perform a scan having a smaller set of PHYs shall reduce the time it takes to find and connect peers. Fixes: 288c90224eec ("Bluetooth: Enable all supported LE PHY by default") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
The extended advertising reports do report the PHYs so this store then
in hci_conn so it can be later used in hci_le_ext_create_conn_sync to
narrow the PHYs to be scanned since the controller will also perform a
scan having a smaller set of PHYs shall reduce the time it takes to
find and connect peers.

Fixes: 288c90224eec ("Bluetooth: Enable all supported LE PHY by default")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: Fix type of len in {l2cap,sco}_sock_getsockopt_old() 2024-04-24T20:26:06+00:00 Nathan Chancellor nathan@kernel.org 2024-04-01T18:24:17+00:00 9bf4e919ccad613b3596eebf1ff37b05b6405307 After an innocuous optimization change in LLVM main (19.0.0), x86_64 allmodconfig (which enables CONFIG_KCSAN / -fsanitize=thread) fails to build due to the checks in check_copy_size(): In file included from net/bluetooth/sco.c:27: In file included from include/linux/module.h:13: In file included from include/linux/stat.h:19: In file included from include/linux/time.h:60: In file included from include/linux/time32.h:13: In file included from include/linux/timex.h:67: In file included from arch/x86/include/asm/timex.h:6: In file included from arch/x86/include/asm/tsc.h:10: In file included from arch/x86/include/asm/msr.h:15: In file included from include/linux/percpu.h:7: In file included from include/linux/smp.h:118: include/linux/thread_info.h:244:4: error: call to '__bad_copy_from' declared with 'error' attribute: copy source size is too small 244 | __bad_copy_from(); | ^ The same exact error occurs in l2cap_sock.c. The copy_to_user() statements that are failing come from l2cap_sock_getsockopt_old() and sco_sock_getsockopt_old(). This does not occur with GCC with or without KCSAN or Clang without KCSAN enabled. len is defined as an 'int' because it is assigned from '__user int *optlen'. However, it is clamped against the result of sizeof(), which has a type of 'size_t' ('unsigned long' for 64-bit platforms). This is done with min_t() because min() requires compatible types, which results in both len and the result of sizeof() being casted to 'unsigned int', meaning len changes signs and the result of sizeof() is truncated. From there, len is passed to copy_to_user(), which has a third parameter type of 'unsigned long', so it is widened and changes signs again. This excessive casting in combination with the KCSAN instrumentation causes LLVM to fail to eliminate the __bad_copy_from() call, failing the build. The official recommendation from LLVM developers is to consistently use long types for all size variables to avoid the unnecessary casting in the first place. Change the type of len to size_t in both l2cap_sock_getsockopt_old() and sco_sock_getsockopt_old(). This clears up the error while allowing min_t() to be replaced with min(), resulting in simpler code with no casts and fewer implicit conversions. While len is a different type than optlen now, it should result in no functional change because the result of sizeof() will clamp all values of optlen in the same manner as before. Cc: stable@vger.kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/2007 Link: https://github.com/llvm/llvm-project/issues/85647 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
After an innocuous optimization change in LLVM main (19.0.0), x86_64
allmodconfig (which enables CONFIG_KCSAN / -fsanitize=thread) fails to
build due to the checks in check_copy_size():

  In file included from net/bluetooth/sco.c:27:
  In file included from include/linux/module.h:13:
  In file included from include/linux/stat.h:19:
  In file included from include/linux/time.h:60:
  In file included from include/linux/time32.h:13:
  In file included from include/linux/timex.h:67:
  In file included from arch/x86/include/asm/timex.h:6:
  In file included from arch/x86/include/asm/tsc.h:10:
  In file included from arch/x86/include/asm/msr.h:15:
  In file included from include/linux/percpu.h:7:
  In file included from include/linux/smp.h:118:
  include/linux/thread_info.h:244:4: error: call to '__bad_copy_from'
  declared with 'error' attribute: copy source size is too small
    244 |                         __bad_copy_from();
        |                         ^

The same exact error occurs in l2cap_sock.c. The copy_to_user()
statements that are failing come from l2cap_sock_getsockopt_old() and
sco_sock_getsockopt_old(). This does not occur with GCC with or without
KCSAN or Clang without KCSAN enabled.

len is defined as an 'int' because it is assigned from
'__user int *optlen'. However, it is clamped against the result of
sizeof(), which has a type of 'size_t' ('unsigned long' for 64-bit
platforms). This is done with min_t() because min() requires compatible
types, which results in both len and the result of sizeof() being casted
to 'unsigned int', meaning len changes signs and the result of sizeof()
is truncated. From there, len is passed to copy_to_user(), which has a
third parameter type of 'unsigned long', so it is widened and changes
signs again. This excessive casting in combination with the KCSAN
instrumentation causes LLVM to fail to eliminate the __bad_copy_from()
call, failing the build.

The official recommendation from LLVM developers is to consistently use
long types for all size variables to avoid the unnecessary casting in
the first place. Change the type of len to size_t in both
l2cap_sock_getsockopt_old() and sco_sock_getsockopt_old(). This clears
up the error while allowing min_t() to be replaced with min(), resulting
in simpler code with no casts and fewer implicit conversions. While len
is a different type than optlen now, it should result in no functional
change because the result of sizeof() will clamp all values of optlen in
the same manner as before.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2007
Link: https://github.com/llvm/llvm-project/issues/85647
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>