commit 9c33663af9 upstream.
This patch adds code to check HCI_UART_PROTO_READY flag before
accessing hci_uart->proto. It fixes the race condition in
hci_uart_tty_ioctl() between HCIUARTSETPROTO and HCIUARTGETPROTO.
This issue bug found by Yu Hao and Weiteng Chen:
BUG: general protection fault in hci_uart_tty_ioctl [1]
The information of C reproducer can also reference the link [2]
Reported-by: Yu Hao <yhao016@ucr.edu>
Closes: https://lore.kernel.org/all/CA+UBctC3p49aTgzbVgkSZ2+TQcqq4fPDO7yZitFT5uBPDeCO2g@mail.gmail.com/ [1]
Reported-by: Weiteng Chen <wchen130@ucr.edu>
Closes: https://lore.kernel.org/lkml/CA+UBctDPEvHdkHMwD340=n02rh+jNRJNNQ5LBZNA+Wm4Keh2ow@mail.gmail.com/T/ [2]
Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
c6a73b7469