5.10-stable review patch. If anyone has any objections, please let me know.
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From: Fedor Pchelkin pchelkin@ispras.ru
commit 5c61419e02033eaf01733d66e2fcd4044808f482 upstream.
One of the possible ways to enable the input MTU auto-selection for L2CAP connections is supposed to be through passing a special "0" value for it as a socket option. Commit [1] added one of those into avdtp. However, it simply wouldn't work because the kernel still treats the specified value as invalid and denies the setting attempt. Recorded BlueZ logs include the following:
bluetoothd[496]: profiles/audio/avdtp.c:l2cap_connect() setsockopt(L2CAP_OPTIONS): Invalid argument (22)
[1]: https://github.com/bluez/bluez/commit/ae5be371a9f53fed33d2b34748a95a5498fd4b...
Found by Linux Verification Center (linuxtesting.org).
Fixes: 4b6e228e297b ("Bluetooth: Auto tune if input MTU is set to 0") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin pchelkin@ispras.ru Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/bluetooth/l2cap_sock.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -727,12 +727,12 @@ static bool l2cap_valid_mtu(struct l2cap { switch (chan->scid) { case L2CAP_CID_ATT: - if (mtu < L2CAP_LE_MIN_MTU) + if (mtu && mtu < L2CAP_LE_MIN_MTU) return false; break;
default: - if (mtu < L2CAP_DEFAULT_MIN_MTU) + if (mtu && mtu < L2CAP_DEFAULT_MIN_MTU) return false; }