summaryrefslogtreecommitdiff
path: root/drivers/isdn
diff options
context:
space:
mode:
authorPeter Hurley <peter@hurleysoftware.com>2014-09-02 21:39:13 (GMT)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-09-08 23:22:42 (GMT)
commitc235ccc1c4d6fd8b7d48b976b87416230ffd5149 (patch)
tree57121108b002bd0f74c4f8efce18dbf823564d2a /drivers/isdn
parent5e42e9a30cdaae51411a9fd4d7de1dc6a7507038 (diff)
downloadlinux-c235ccc1c4d6fd8b7d48b976b87416230ffd5149.tar.xz
serial: core: Fix x_char race
The UART driver is expected to clear port->x_char after transmission while holding the port->lock. However, the serial core fails to take the port->lock before assigning port->xchar. This allows for the following race CPU 0 | CPU 1 | | serial8250_handle_irq | ... | serial8250_tx_chars | if (port->x_char) | serial_out(up, UART_TX, port->x_char) uart_send_xchar | port->x_char = ch | | port->x_char = 0 port->ops->start_tx() | | The x_char on CPU 0 will never be sent. Take the port->lock in uart_send_xchar() before assigning port->x_char. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/isdn')
0 files changed, 0 insertions, 0 deletions