diff options
| author | Luiz Augusto von Dentz | 2022-09-13 16:08:13 -0700 |
|---|---|---|
| committer | Luiz Augusto von Dentz | 2022-09-15 14:07:59 -0700 |
| commit | 812e92b824c1db16c9519f8624d48a9901a0d38f (patch) | |
| tree | a5348faefef4e12ff8cc766fc3a903463be0b36e | |
| parent | 9afc675edeeb34d281675f1d5a217d27c5a1a3db (diff) | |
Bluetooth: RFCOMM: Fix possible deadlock on socket shutdown/release
Due to change to switch to use lock_sock inside rfcomm_sk_state_change
the socket shutdown/release procedure can cause a deadlock:
rfcomm_sock_shutdown():
lock_sock();
__rfcomm_sock_close():
rfcomm_dlc_close():
__rfcomm_dlc_close():
rfcomm_dlc_lock();
rfcomm_sk_state_change():
lock_sock();
To fix this when the call __rfcomm_sock_close is now done without
holding the lock_sock since rfcomm_dlc_lock exists to protect
the dlc data there is no need to use lock_sock in that code path.
Link: https://lore.kernel.org/all/CAD+dNTsbuU4w+Y_P7o+VEN7BYCAbZuwZx2+tH+OTzCdcZF82YA@mail.gmail.com/
Fixes: b7ce436a5d79 ("Bluetooth: switch to lock_sock in RFCOMM")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
| -rw-r--r-- | net/bluetooth/rfcomm/sock.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c index 4bf4ea6cbb5e..21e24da4847f 100644 --- a/net/bluetooth/rfcomm/sock.c +++ b/net/bluetooth/rfcomm/sock.c @@ -902,7 +902,10 @@ static int rfcomm_sock_shutdown(struct socket *sock, int how) lock_sock(sk); if (!sk->sk_shutdown) { sk->sk_shutdown = SHUTDOWN_MASK; + + release_sock(sk); __rfcomm_sock_close(sk); + lock_sock(sk); if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime && !(current->flags & PF_EXITING)) |