diff mbox series

Bluetooth: Prevent double register of suspend

Message ID 20220926163057.1.Ia168b651a69b253059f2bbaa60b98083e619545c@changeid
State New
Headers show
Series Bluetooth: Prevent double register of suspend | expand

Commit Message

Abhishek Pandit-Subedi Sept. 26, 2022, 11:31 p.m. UTC 
From: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>

Suspend notifier should only be registered and unregistered once per
hdev. Since hci_sock and hci_register_dev run in different work queues
(sock vs driver), add hci_dev_lock to avoid double registering.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---
This is fixing a syzbot reported warning. Tested in the following ways:
* Normal start-up of driver with bluez.
* Start/stop loop using HCI_USER_CHANNEL (sock path).
* USB reset triggering hci_dev_unregister (driver path).

------------[ cut here ]------------
double register detected
WARNING: CPU: 0 PID: 2657 at kernel/notifier.c:27
notifier_chain_register kernel/notifier.c:27 [inline]
WARNING: CPU: 0 PID: 2657 at kernel/notifier.c:27
notifier_chain_register+0x5c/0x124 kernel/notifier.c:22
Modules linked in:
CPU: 0 PID: 2657 Comm: syz-executor212 Not tainted
5.10.136-syzkaller-19376-g6f46a5fe0124 #0
  8f0771607702f5ef7184d2ee33bd0acd70219fc4
  Hardware name: Google Google Compute Engine/Google Compute Engine,
  BIOS Google 07/22/2022
  RIP: 0010:notifier_chain_register kernel/notifier.c:27 [inline]
  RIP: 0010:notifier_chain_register+0x5c/0x124 kernel/notifier.c:22
  Code: 6a 41 00 4c 8b 23 4d 85 e4 0f 84 88 00 00 00 e8 c2 1e 19 00 49
  39 ec 75 18 e8 b8 1e 19 00 48 c7 c7 80 6d ca 84 e8 2c 68 48 03 <0f> 0b
     e9 af 00 00 00 e8 a0 1e 19 00 48 8d 7d 10 48 89 f8 48 c1 e8
     RSP: 0018:ffffc900009d7da8 EFLAGS: 00010286
     RAX: 0000000000000000 RBX: ffff8881076fd1d8 RCX: 0000000000000000
     RDX: 0000001810895100 RSI: ffff888110895100 RDI: fffff5200013afa7
     RBP: ffff88811a4191d0 R08: ffffffff813b8ca1 R09: 0000000080000000
     R10: 0000000000000000 R11: 0000000000000005 R12: ffff88811a4191d0
     R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
     FS: 00005555571f5300(0000) GS:ffff8881f6c00000(0000)
     knlGS:0000000000000000
     CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
     CR2: 000078e3857f3075 CR3: 000000010d668000 CR4: 00000000003506f0
     DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
     DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
     Call Trace:
     blocking_notifier_chain_register+0x8c/0xa6 kernel/notifier.c:254
     hci_register_suspend_notifier net/bluetooth/hci_core.c:2733
     [inline]
     hci_register_suspend_notifier+0x6b/0x7c
     net/bluetooth/hci_core.c:2727
     hci_sock_release+0x270/0x3cf net/bluetooth/hci_sock.c:889
     __sock_release+0xcd/0x1de net/socket.c:597
     sock_close+0x18/0x1c net/socket.c:1267
     __fput+0x418/0x729 fs/file_table.c:281
     task_work_run+0x12b/0x15b kernel/task_work.c:151
     tracehook_notify_resume include/linux/tracehook.h:188 [inline]
     exit_to_user_mode_loop kernel/entry/common.c:165 [inline]
     exit_to_user_mode_prepare+0x8f/0x130 kernel/entry/common.c:192
     syscall_exit_to_user_mode+0x172/0x1b2 kernel/entry/common.c:268
     entry_SYSCALL_64_after_hwframe+0x61/0xc6
     RIP: 0033:0x78e38575e1db
     Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89
     7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05
     <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
     RSP: 002b:00007ffffc20a0b0 EFLAGS: 00000293 ORIG_RAX:
     0000000000000003
     RAX: 0000000000000000 RBX: 0000000000000006 RCX: 000078e38575e1db
     RDX: ffffffffffffffb8 RSI: 0000000020000000 RDI: 0000000000000005
     RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000150
     R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000e155
     R13: 00007ffffc20a140 R14: 00007ffffc20a130 R15: 00007ffffc20a0e8

 include/net/bluetooth/hci.h |  1 +
 net/bluetooth/hci_core.c    | 16 ++++++++++++++--
 2 files changed, 15 insertions(+), 2 deletions(-)

Comments

Abhishek Pandit-Subedi Sept. 26, 2022, 11:59 p.m. UTC | #1 
Actually, yeah that's a much simpler change... Got a little
tunnel-visioned trying to fix the error :)
I'll send up a v2 tomorrow after testing.

On Mon, Sep 26, 2022 at 4:55 PM Luiz Augusto von Dentz
<luiz.dentz@gmail.com> wrote:
>
> Hi Abhishek,
>
> On Mon, Sep 26, 2022 at 4:31 PM Abhishek Pandit-Subedi
> <abhishekpandit@google.com> wrote:
> >
> > From: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> >
> > Suspend notifier should only be registered and unregistered once per
> > hdev. Since hci_sock and hci_register_dev run in different work queues
> > (sock vs driver), add hci_dev_lock to avoid double registering.
> >
> > Reported-by: syzbot <syzkaller@googlegroups.com>
> > Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> > ---
> > This is fixing a syzbot reported warning. Tested in the following ways:
> > * Normal start-up of driver with bluez.
> > * Start/stop loop using HCI_USER_CHANNEL (sock path).
> > * USB reset triggering hci_dev_unregister (driver path).
> >
> > ------------[ cut here ]------------
> > double register detected
> > WARNING: CPU: 0 PID: 2657 at kernel/notifier.c:27
> > notifier_chain_register kernel/notifier.c:27 [inline]
> > WARNING: CPU: 0 PID: 2657 at kernel/notifier.c:27
> > notifier_chain_register+0x5c/0x124 kernel/notifier.c:22
> > Modules linked in:
> > CPU: 0 PID: 2657 Comm: syz-executor212 Not tainted
> > 5.10.136-syzkaller-19376-g6f46a5fe0124 #0
> >   8f0771607702f5ef7184d2ee33bd0acd70219fc4
> >   Hardware name: Google Google Compute Engine/Google Compute Engine,
> >   BIOS Google 07/22/2022
> >   RIP: 0010:notifier_chain_register kernel/notifier.c:27 [inline]
> >   RIP: 0010:notifier_chain_register+0x5c/0x124 kernel/notifier.c:22
> >   Code: 6a 41 00 4c 8b 23 4d 85 e4 0f 84 88 00 00 00 e8 c2 1e 19 00 49
> >   39 ec 75 18 e8 b8 1e 19 00 48 c7 c7 80 6d ca 84 e8 2c 68 48 03 <0f> 0b
> >      e9 af 00 00 00 e8 a0 1e 19 00 48 8d 7d 10 48 89 f8 48 c1 e8
> >      RSP: 0018:ffffc900009d7da8 EFLAGS: 00010286
> >      RAX: 0000000000000000 RBX: ffff8881076fd1d8 RCX: 0000000000000000
> >      RDX: 0000001810895100 RSI: ffff888110895100 RDI: fffff5200013afa7
> >      RBP: ffff88811a4191d0 R08: ffffffff813b8ca1 R09: 0000000080000000
> >      R10: 0000000000000000 R11: 0000000000000005 R12: ffff88811a4191d0
> >      R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
> >      FS: 00005555571f5300(0000) GS:ffff8881f6c00000(0000)
> >      knlGS:0000000000000000
> >      CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> >      CR2: 000078e3857f3075 CR3: 000000010d668000 CR4: 00000000003506f0
> >      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> >      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> >      Call Trace:
> >      blocking_notifier_chain_register+0x8c/0xa6 kernel/notifier.c:254
> >      hci_register_suspend_notifier net/bluetooth/hci_core.c:2733
> >      [inline]
> >      hci_register_suspend_notifier+0x6b/0x7c
> >      net/bluetooth/hci_core.c:2727
> >      hci_sock_release+0x270/0x3cf net/bluetooth/hci_sock.c:889
> >      __sock_release+0xcd/0x1de net/socket.c:597
> >      sock_close+0x18/0x1c net/socket.c:1267
> >      __fput+0x418/0x729 fs/file_table.c:281
> >      task_work_run+0x12b/0x15b kernel/task_work.c:151
> >      tracehook_notify_resume include/linux/tracehook.h:188 [inline]
> >      exit_to_user_mode_loop kernel/entry/common.c:165 [inline]
> >      exit_to_user_mode_prepare+0x8f/0x130 kernel/entry/common.c:192
> >      syscall_exit_to_user_mode+0x172/0x1b2 kernel/entry/common.c:268
> >      entry_SYSCALL_64_after_hwframe+0x61/0xc6
> >      RIP: 0033:0x78e38575e1db
> >      Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89
> >      7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05
> >      <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
> >      RSP: 002b:00007ffffc20a0b0 EFLAGS: 00000293 ORIG_RAX:
> >      0000000000000003
> >      RAX: 0000000000000000 RBX: 0000000000000006 RCX: 000078e38575e1db
> >      RDX: ffffffffffffffb8 RSI: 0000000020000000 RDI: 0000000000000005
> >      RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000150
> >      R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000e155
> >      R13: 00007ffffc20a140 R14: 00007ffffc20a130 R15: 00007ffffc20a0e8
> >
> >  include/net/bluetooth/hci.h |  1 +
> >  net/bluetooth/hci_core.c    | 16 ++++++++++++++--
> >  2 files changed, 15 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> > index e004ba04a9ae..36304c217151 100644
> > --- a/include/net/bluetooth/hci.h
> > +++ b/include/net/bluetooth/hci.h
> > @@ -353,6 +353,7 @@ enum {
> >         HCI_OFFLOAD_CODECS_ENABLED,
> >         HCI_LE_SIMULTANEOUS_ROLES,
> >         HCI_CMD_DRAIN_WORKQUEUE,
> > +       HCI_SUSPEND_REGISTERED,
> >
> >         HCI_MESH_EXPERIMENTAL,
> >         HCI_MESH,
> > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> > index 66c7cdba0d32..5a32d17c69b8 100644
> > --- a/net/bluetooth/hci_core.c
> > +++ b/net/bluetooth/hci_core.c
> > @@ -2760,10 +2760,18 @@ int hci_register_suspend_notifier(struct hci_dev *hdev)
> >  {
> >         int ret = 0;
> >
> > -       if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks)) {
> > +       hci_dev_lock(hdev);
> > +       if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks) &&
> > +           !hci_dev_test_and_set_flag(hdev, HCI_SUSPEND_REGISTERED)) {
> > +               memset(&hdev->suspend_notifier, 0,
> > +                      sizeof(hdev->suspend_notifier));
> >                 hdev->suspend_notifier.notifier_call = hci_suspend_notifier;
> >                 ret = register_pm_notifier(&hdev->suspend_notifier);
> > +
> > +               if (ret)
> > +                       hci_dev_clear_flag(hdev, HCI_SUSPEND_REGISTERED);
> >         }
> > +       hci_dev_unlock(hdev);
> >
> >         return ret;
> >  }
> > @@ -2772,8 +2780,12 @@ int hci_unregister_suspend_notifier(struct hci_dev *hdev)
> >  {
> >         int ret = 0;
> >
> > -       if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks))
> > +       hci_dev_lock(hdev);
> > +       if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks) &&
> > +           hci_dev_test_and_clear_flag(hdev, HCI_SUSPEND_REGISTERED)) {
> >                 ret = unregister_pm_notifier(&hdev->suspend_notifier);
> > +       }
> > +       hci_dev_unlock(hdev);
> >
> >         return ret;
> >  }
>
> Perhaps it would have been better to stop calling these on hci_sock.c
> and just make the notifier callback check
> hci_dev_test_and_set_flag(hdev, HCI_USER_CHANNEL) return NOTIFY_DONE.
>
> > --
> > 2.37.3.998.g577e59143f-goog
> >
>
>
> --
> Luiz Augusto von Dentz
bluez.test.bot@gmail.com Sept. 27, 2022, 12:20 a.m. UTC | #2 
This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=680770

---Test result---

Test Summary:
CheckPatch                    PASS      1.16 seconds
GitLint                       PASS      0.47 seconds
SubjectPrefix                 PASS      0.31 seconds
BuildKernel                   PASS      48.10 seconds
BuildKernel32                 PASS      41.63 seconds
Incremental Build with patchesPASS      59.24 seconds
TestRunner: Setup             PASS      700.91 seconds
TestRunner: l2cap-tester      PASS      21.04 seconds
TestRunner: iso-tester        PASS      21.89 seconds
TestRunner: bnep-tester       PASS      8.31 seconds
TestRunner: mgmt-tester       PASS      136.48 seconds
TestRunner: rfcomm-tester     PASS      13.33 seconds
TestRunner: sco-tester        PASS      12.64 seconds
TestRunner: ioctl-tester      PASS      13.88 seconds
TestRunner: smp-tester        PASS      12.32 seconds
TestRunner: userchan-tester   PASS      9.08 seconds



---
Regards,
Linux Bluetooth
diff mbox series

Patch

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index e004ba04a9ae..36304c217151 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -353,6 +353,7 @@  enum {
 	HCI_OFFLOAD_CODECS_ENABLED,
 	HCI_LE_SIMULTANEOUS_ROLES,
 	HCI_CMD_DRAIN_WORKQUEUE,
+	HCI_SUSPEND_REGISTERED,
 
 	HCI_MESH_EXPERIMENTAL,
 	HCI_MESH,
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 66c7cdba0d32..5a32d17c69b8 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2760,10 +2760,18 @@  int hci_register_suspend_notifier(struct hci_dev *hdev)
 {
 	int ret = 0;
 
-	if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks)) {
+	hci_dev_lock(hdev);
+	if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks) &&
+	    !hci_dev_test_and_set_flag(hdev, HCI_SUSPEND_REGISTERED)) {
+		memset(&hdev->suspend_notifier, 0,
+		       sizeof(hdev->suspend_notifier));
 		hdev->suspend_notifier.notifier_call = hci_suspend_notifier;
 		ret = register_pm_notifier(&hdev->suspend_notifier);
+
+		if (ret)
+			hci_dev_clear_flag(hdev, HCI_SUSPEND_REGISTERED);
 	}
+	hci_dev_unlock(hdev);
 
 	return ret;
 }
@@ -2772,8 +2780,12 @@  int hci_unregister_suspend_notifier(struct hci_dev *hdev)
 {
 	int ret = 0;
 
-	if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks))
+	hci_dev_lock(hdev);
+	if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks) &&
+	    hci_dev_test_and_clear_flag(hdev, HCI_SUSPEND_REGISTERED)) {
 		ret = unregister_pm_notifier(&hdev->suspend_notifier);
+	}
+	hci_dev_unlock(hdev);
 
 	return ret;
 }