This bug was found by syzkaller.
This bug is also very similar to another RFCOMM possible deadlock
in rfcomm_dlc_exists. Both of these bugs are present in syzbot.
Patch fixes two of these possible dedlock errors.
Also this particular patch was already written in march of 2023
by Hillf Danton, but seems like it just got lost or forgotten.
Links to these bugs and original patch on syzbot:
Link: https://syzkaller.appspot.com/bug?extid=b69a625d06e8ece26415
Link: https://syzkaller.appspot.com/bug?extid=d7ce59b06b3eb14fd218
Link: https://syzkaller.appspot.com/text?tag=Patch&x=133a6835c80000
Signed-off-by: Alexander Ofitserov <[email protected]>
---
net/bluetooth/rfcomm/core.c | 2 +-
net/bluetooth/rfcomm/sock.c | 2 --
net/bluetooth/rfcomm/tty.c | 11 +++++++----
3 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index 1d34d849703329..d8502914e3602c 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -490,8 +490,8 @@ static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
rfcomm_dlc_lock(d);
d->state = BT_CLOSED;
- d->state_change(d, err);
rfcomm_dlc_unlock(d);
+ d->state_change(d, err);
skb_queue_purge(&d->tx_queue);
rfcomm_dlc_unlink(d);
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 29aa07e9db9d71..cbff37b3273407 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -865,9 +865,7 @@ static int rfcomm_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned lon
if (err == -ENOIOCTLCMD) {
#ifdef CONFIG_BT_RFCOMM_TTY
- lock_sock(sk);
err = rfcomm_dev_ioctl(sk, cmd, (void __user *) arg);
- release_sock(sk);
#else
err = -EOPNOTSUPP;
#endif
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index 69c75c041fe10a..5be21b987141fc 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -403,9 +403,12 @@ static int __rfcomm_create_dev(struct sock *sk, void __user *arg)
return -EPERM;
if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
+ lock_sock(sk);
/* Socket must be connected */
- if (sk->sk_state != BT_CONNECTED)
+ if (sk->sk_state != BT_CONNECTED) {
+ release_sock(sk);
return -EBADFD;
+ }
dlc = rfcomm_pi(sk)->dlc;
rfcomm_dlc_hold(dlc);
@@ -422,13 +425,13 @@ static int __rfcomm_create_dev(struct sock *sk, void __user *arg)
}
id = rfcomm_dev_add(&req, dlc);
- if (id < 0)
- return id;
if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
/* DLC is now used by device.
* Socket must be disconnected */
- sk->sk_state = BT_CLOSED;
+ if (!(id < 0))
+ sk->sk_state = BT_CLOSED;
+ release_sock(sk);
}
return id;
--
2.42.1
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=851144
---Test result---
Test Summary:
CheckPatch PASS 0.94 seconds
GitLint PASS 0.27 seconds
SubjectPrefix PASS 0.09 seconds
BuildKernel PASS 30.21 seconds
CheckAllWarning PASS 33.33 seconds
CheckSparse PASS 38.87 seconds
CheckSmatch FAIL 36.55 seconds
BuildKernel32 PASS 29.16 seconds
TestRunnerSetup PASS 526.28 seconds
TestRunner_l2cap-tester PASS 18.55 seconds
TestRunner_iso-tester FAIL 33.83 seconds
TestRunner_bnep-tester PASS 4.72 seconds
TestRunner_mgmt-tester PASS 107.38 seconds
TestRunner_rfcomm-tester PASS 7.35 seconds
TestRunner_sco-tester PASS 15.08 seconds
TestRunner_ioctl-tester PASS 7.69 seconds
TestRunner_mesh-tester PASS 5.76 seconds
TestRunner_smp-tester PASS 6.77 seconds
TestRunner_userchan-tester PASS 4.91 seconds
IncrementalBuild PASS 28.57 seconds
Details
##############################
Test: CheckSmatch - FAIL
Desc: Run smatch tool with source
Output:
Segmentation fault (core dumped)
make[4]: *** [scripts/Makefile.build:244: net/bluetooth/hci_core.o] Error 139
make[4]: *** Deleting file 'net/bluetooth/hci_core.o'
make[3]: *** [scripts/Makefile.build:485: net/bluetooth] Error 2
make[2]: *** [scripts/Makefile.build:485: net] Error 2
make[2]: *** Waiting for unfinished jobs....
Segmentation fault (core dumped)
make[4]: *** [scripts/Makefile.build:244: drivers/bluetooth/bcm203x.o] Error 139
make[4]: *** Deleting file 'drivers/bluetooth/bcm203x.o'
make[4]: *** Waiting for unfinished jobs....
Segmentation fault (core dumped)
make[4]: *** [scripts/Makefile.build:244: drivers/bluetooth/bpa10x.o] Error 139
make[4]: *** Deleting file 'drivers/bluetooth/bpa10x.o'
make[3]: *** [scripts/Makefile.build:485: drivers/bluetooth] Error 2
make[2]: *** [scripts/Makefile.build:485: drivers] Error 2
make[1]: *** [/github/workspace/src/src/Makefile:1919: .] Error 2
make: *** [Makefile:240: __sub-make] Error 2
##############################
Test: TestRunner_iso-tester - FAIL
Desc: Run iso-tester with test-runner
Output:
Total: 122, Passed: 121 (99.2%), Failed: 1, Not Run: 0
Failed Test Cases
ISO Connect2 Suspend - Success Failed 6.251 seconds
---
Regards,
Linux Bluetooth