diff mbox series

[v1] Bluetooth: af_bluetooth: Fix deadlock

Message ID 20240301185034.2756103-1-luiz.dentz@gmail.com (mailing list archive)
State Accepted
Commit 40245851528a82951de835a8b2a43d487f11b6d5
Headers show
Series [v1] Bluetooth: af_bluetooth: Fix deadlock | expand

Checks

Context Check Description
tedd_an/pre-ci_am success Success
tedd_an/CheckPatch success CheckPatch PASS
tedd_an/GitLint success Gitlint PASS
tedd_an/SubjectPrefix success Gitlint PASS
tedd_an/BuildKernel success BuildKernel PASS
tedd_an/CheckAllWarning success CheckAllWarning PASS
tedd_an/CheckSparse warning CheckSparse WARNING net/bluetooth/af_bluetooth.c:223:25: warning: context imbalance in 'bt_accept_enqueue' - different lock contexts for basic block
tedd_an/CheckSmatch success CheckSparse PASS
tedd_an/BuildKernel32 success BuildKernel32 PASS
tedd_an/TestRunnerSetup success TestRunnerSetup PASS
tedd_an/TestRunner_l2cap-tester success TestRunner PASS
tedd_an/TestRunner_iso-tester success TestRunner PASS
tedd_an/TestRunner_bnep-tester success TestRunner PASS
tedd_an/TestRunner_mgmt-tester fail TestRunner_mgmt-tester: Total: 492, Passed: 489 (99.4%), Failed: 1, Not Run: 2
tedd_an/TestRunner_rfcomm-tester success TestRunner PASS
tedd_an/TestRunner_sco-tester success TestRunner PASS
tedd_an/TestRunner_ioctl-tester success TestRunner PASS
tedd_an/TestRunner_mesh-tester success TestRunner PASS
tedd_an/TestRunner_smp-tester success TestRunner PASS
tedd_an/TestRunner_userchan-tester success TestRunner PASS
tedd_an/IncrementalBuild success Incremental Build PASS

Commit Message

Luiz Augusto von Dentz March 1, 2024, 6:50 p.m. UTC 
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

Attemting to do sock_lock on .recvmsg may cause a deadlock as shown
bellow, so instead of using sock_sock this uses sk_receive_queue.lock
on bt_sock_ioctl to avoid the UAF:

INFO: task kworker/u9:1:121 blocked for more than 30 seconds.
      Not tainted 6.7.6-lemon #183
Workqueue: hci0 hci_rx_work
Call Trace:
 <TASK>
 __schedule+0x37d/0xa00
 schedule+0x32/0xe0
 __lock_sock+0x68/0xa0
 ? __pfx_autoremove_wake_function+0x10/0x10
 lock_sock_nested+0x43/0x50
 l2cap_sock_recv_cb+0x21/0xa0
 l2cap_recv_frame+0x55b/0x30a0
 ? psi_task_switch+0xeb/0x270
 ? finish_task_switch.isra.0+0x93/0x2a0
 hci_rx_work+0x33a/0x3f0
 process_one_work+0x13a/0x2f0
 worker_thread+0x2f0/0x410
 ? __pfx_worker_thread+0x10/0x10
 kthread+0xe0/0x110
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x2c/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1b/0x30
 </TASK>

Fixes: 2e07e8348ea4 ("Bluetooth: af_bluetooth: Fix Use-After-Free in bt_sock_recvmsg")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 net/bluetooth/af_bluetooth.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

Comments

Luiz Augusto von Dentz March 1, 2024, 7 p.m. UTC | #1 
On Fri, Mar 1, 2024 at 1:50 PM Luiz Augusto von Dentz
<luiz.dentz@gmail.com> wrote:
>
> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
>
> Attemting to do sock_lock on .recvmsg may cause a deadlock as shown
> bellow, so instead of using sock_sock this uses sk_receive_queue.lock
> on bt_sock_ioctl to avoid the UAF:
>
> INFO: task kworker/u9:1:121 blocked for more than 30 seconds.
>       Not tainted 6.7.6-lemon #183
> Workqueue: hci0 hci_rx_work
> Call Trace:
>  <TASK>
>  __schedule+0x37d/0xa00
>  schedule+0x32/0xe0
>  __lock_sock+0x68/0xa0
>  ? __pfx_autoremove_wake_function+0x10/0x10
>  lock_sock_nested+0x43/0x50
>  l2cap_sock_recv_cb+0x21/0xa0
>  l2cap_recv_frame+0x55b/0x30a0
>  ? psi_task_switch+0xeb/0x270
>  ? finish_task_switch.isra.0+0x93/0x2a0
>  hci_rx_work+0x33a/0x3f0
>  process_one_work+0x13a/0x2f0
>  worker_thread+0x2f0/0x410
>  ? __pfx_worker_thread+0x10/0x10
>  kthread+0xe0/0x110
>  ? __pfx_kthread+0x10/0x10
>  ret_from_fork+0x2c/0x50
>  ? __pfx_kthread+0x10/0x10
>  ret_from_fork_asm+0x1b/0x30
>  </TASK>
>
> Fixes: 2e07e8348ea4 ("Bluetooth: af_bluetooth: Fix Use-After-Free in bt_sock_recvmsg")
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> ---
>  net/bluetooth/af_bluetooth.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
> index b93464ac3517..67604ccec2f4 100644
> --- a/net/bluetooth/af_bluetooth.c
> +++ b/net/bluetooth/af_bluetooth.c
> @@ -309,14 +309,11 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
>         if (flags & MSG_OOB)
>                 return -EOPNOTSUPP;
>
> -       lock_sock(sk);
> -
>         skb = skb_recv_datagram(sk, flags, &err);
>         if (!skb) {
>                 if (sk->sk_shutdown & RCV_SHUTDOWN)
>                         err = 0;
>
> -               release_sock(sk);
>                 return err;
>         }
>
> @@ -346,8 +343,6 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
>
>         skb_free_datagram(sk, skb);
>
> -       release_sock(sk);
> -
>         if (flags & MSG_TRUNC)
>                 copied = skblen;
>
> @@ -570,10 +565,11 @@ int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
>                 if (sk->sk_state == BT_LISTEN)
>                         return -EINVAL;
>
> -               lock_sock(sk);
> +               spin_lock(&sk->sk_receive_queue.lock);
>                 skb = skb_peek(&sk->sk_receive_queue);
>                 amount = skb ? skb->len : 0;
> -               release_sock(sk);
> +               spin_unlock(&sk->sk_receive_queue.lock);
> +
>                 err = put_user(amount, (int __user *)arg);
>                 break;
>
> --
> 2.43.0
>
bluez.test.bot@gmail.com March 1, 2024, 7:42 p.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=831666

---Test result---

Test Summary:
CheckPatch                    PASS      0.66 seconds
GitLint                       PASS      0.32 seconds
SubjectPrefix                 PASS      0.12 seconds
BuildKernel                   PASS      28.28 seconds
CheckAllWarning               PASS      30.85 seconds
CheckSparse                   WARNING   36.83 seconds
CheckSmatch                   PASS      98.99 seconds
BuildKernel32                 PASS      27.51 seconds
TestRunnerSetup               PASS      505.14 seconds
TestRunner_l2cap-tester       PASS      20.25 seconds
TestRunner_iso-tester         PASS      32.70 seconds
TestRunner_bnep-tester        PASS      4.81 seconds
TestRunner_mgmt-tester        FAIL      114.53 seconds
TestRunner_rfcomm-tester      PASS      7.45 seconds
TestRunner_sco-tester         PASS      15.01 seconds
TestRunner_ioctl-tester       PASS      8.04 seconds
TestRunner_mesh-tester        PASS      6.02 seconds
TestRunner_smp-tester         PASS      6.93 seconds
TestRunner_userchan-tester    PASS      5.01 seconds
IncrementalBuild              PASS      26.39 seconds

Details
##############################
Test: CheckSparse - WARNING
Desc: Run sparse tool with linux kernel
Output:
net/bluetooth/af_bluetooth.c:223:25: warning: context imbalance in 'bt_accept_enqueue' - different lock contexts for basic block
##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 492, Passed: 489 (99.4%), Failed: 1, Not Run: 2

Failed Test Cases
LL Privacy - Add Device 6 (RL is full)               Failed       0.194 seconds


---
Regards,
Linux Bluetooth
patchwork-bot+bluetooth@kernel.org March 4, 2024, 4:30 p.m. UTC | #3 
Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>:

On Fri,  1 Mar 2024 13:50:34 -0500 you wrote:
> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> 
> Attemting to do sock_lock on .recvmsg may cause a deadlock as shown
> bellow, so instead of using sock_sock this uses sk_receive_queue.lock
> on bt_sock_ioctl to avoid the UAF:
> 
> INFO: task kworker/u9:1:121 blocked for more than 30 seconds.
>       Not tainted 6.7.6-lemon #183
> Workqueue: hci0 hci_rx_work
> Call Trace:
>  <TASK>
>  __schedule+0x37d/0xa00
>  schedule+0x32/0xe0
>  __lock_sock+0x68/0xa0
>  ? __pfx_autoremove_wake_function+0x10/0x10
>  lock_sock_nested+0x43/0x50
>  l2cap_sock_recv_cb+0x21/0xa0
>  l2cap_recv_frame+0x55b/0x30a0
>  ? psi_task_switch+0xeb/0x270
>  ? finish_task_switch.isra.0+0x93/0x2a0
>  hci_rx_work+0x33a/0x3f0
>  process_one_work+0x13a/0x2f0
>  worker_thread+0x2f0/0x410
>  ? __pfx_worker_thread+0x10/0x10
>  kthread+0xe0/0x110
>  ? __pfx_kthread+0x10/0x10
>  ret_from_fork+0x2c/0x50
>  ? __pfx_kthread+0x10/0x10
>  ret_from_fork_asm+0x1b/0x30
>  </TASK>
> 
> [...]

Here is the summary with links:
  - [v1] Bluetooth: af_bluetooth: Fix deadlock
    https://git.kernel.org/bluetooth/bluetooth-next/c/40245851528a

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index b93464ac3517..67604ccec2f4 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -309,14 +309,11 @@  int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	if (flags & MSG_OOB)
 		return -EOPNOTSUPP;
 
-	lock_sock(sk);
-
 	skb = skb_recv_datagram(sk, flags, &err);
 	if (!skb) {
 		if (sk->sk_shutdown & RCV_SHUTDOWN)
 			err = 0;
 
-		release_sock(sk);
 		return err;
 	}
 
@@ -346,8 +343,6 @@  int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 
 	skb_free_datagram(sk, skb);
 
-	release_sock(sk);
-
 	if (flags & MSG_TRUNC)
 		copied = skblen;
 
@@ -570,10 +565,11 @@  int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 		if (sk->sk_state == BT_LISTEN)
 			return -EINVAL;
 
-		lock_sock(sk);
+		spin_lock(&sk->sk_receive_queue.lock);
 		skb = skb_peek(&sk->sk_receive_queue);
 		amount = skb ? skb->len : 0;
-		release_sock(sk);
+		spin_unlock(&sk->sk_receive_queue.lock);
+
 		err = put_user(amount, (int __user *)arg);
 		break;