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| author | Sergey Organov <sorganov@gmail.com> | 2019-06-11 15:05:24 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-18 09:30:44 +0200 |
| commit | 4e828c3e09201512be5ee162393f334321f7cf01 (patch) | |
| tree | 9fb2200d817392b94e97300177b014004f23ef29 /drivers/tty/serial/imx.c | |
| parent | da0f843e6e6ff23790e9d97a05dc555ee2e3fa11 (diff) | |
| download | linux-stable-4e828c3e09201512be5ee162393f334321f7cf01.tar.gz linux-stable-4e828c3e09201512be5ee162393f334321f7cf01.tar.bz2 linux-stable-4e828c3e09201512be5ee162393f334321f7cf01.zip | |
serial: imx: fix locking in set_termios()
imx_uart_set_termios() called imx_uart_rts_active(), or
imx_uart_rts_inactive() before taking port->port.lock.
As a consequence, sport->port.mctrl that these functions modify
could have been changed without holding port->port.lock.
Moved locking of port->port.lock above the calls to fix the issue.
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index d8eadab02446..52374b37d272 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -383,6 +383,7 @@ static void imx_uart_ucrs_restore(struct imx_port *sport, } #endif +/* called with port.lock taken and irqs caller dependent */ static void imx_uart_rts_active(struct imx_port *sport, u32 *ucr2) { *ucr2 &= ~(UCR2_CTSC | UCR2_CTS); @@ -391,6 +392,7 @@ static void imx_uart_rts_active(struct imx_port *sport, u32 *ucr2) mctrl_gpio_set(sport->gpios, sport->port.mctrl); } +/* called with port.lock taken and irqs caller dependent */ static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2) { *ucr2 &= ~UCR2_CTSC; @@ -400,6 +402,7 @@ static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2) mctrl_gpio_set(sport->gpios, sport->port.mctrl); } +/* called with port.lock taken and irqs caller dependent */ static void imx_uart_rts_auto(struct imx_port *sport, u32 *ucr2) { *ucr2 |= UCR2_CTSC; @@ -1549,6 +1552,16 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, old_csize = CS8; } + del_timer_sync(&sport->timer); + + /* + * Ask the core to calculate the divisor for us. + */ + baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16); + quot = uart_get_divisor(port, baud); + + spin_lock_irqsave(&sport->port.lock, flags); + if ((termios->c_cflag & CSIZE) == CS8) ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS; else @@ -1592,16 +1605,6 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, ucr2 |= UCR2_PROE; } - del_timer_sync(&sport->timer); - - /* - * Ask the core to calculate the divisor for us. - */ - baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16); - quot = uart_get_divisor(port, baud); - - spin_lock_irqsave(&sport->port.lock, flags); - sport->port.read_status_mask = 0; if (termios->c_iflag & INPCK) sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR); |