mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
serial: serial_core: Perform NULL checks for release/request_port ops
Doing the following UART bind/unbind sequence on a i.mx platform causes a kernel crash due to NULL pointer dereference: echo 21f4000.serial > /sys/bus/platform/drivers/imx-uart/bind echo 21f4000.serial > /sys/bus/platform/drivers/imx-uart/unbind Fix this problem by adding NULL checks prior to calling release/request_port ops. Reported-by: Fugang Duan <fugang.duan@nxp.com> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Tested-by: Fugang Duan <fugang.duan@nxp.com> Acked-by: Fugang Duan <fugang.duan@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
3e5af8e04a
commit
a7cfaf165e
1 changed files with 4 additions and 4 deletions
|
@ -887,7 +887,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
|
|||
/*
|
||||
* Free and release old regions
|
||||
*/
|
||||
if (old_type != PORT_UNKNOWN)
|
||||
if (old_type != PORT_UNKNOWN && uport->ops->release_port)
|
||||
uport->ops->release_port(uport);
|
||||
|
||||
uport->iobase = new_port;
|
||||
|
@ -900,7 +900,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
|
|||
/*
|
||||
* Claim and map the new regions
|
||||
*/
|
||||
if (uport->type != PORT_UNKNOWN) {
|
||||
if (uport->type != PORT_UNKNOWN && uport->ops->request_port) {
|
||||
retval = uport->ops->request_port(uport);
|
||||
} else {
|
||||
/* Always success - Jean II */
|
||||
|
@ -1125,7 +1125,7 @@ static int uart_do_autoconfig(struct tty_struct *tty,struct uart_state *state)
|
|||
* If we already have a port type configured,
|
||||
* we must release its resources.
|
||||
*/
|
||||
if (uport->type != PORT_UNKNOWN)
|
||||
if (uport->type != PORT_UNKNOWN && uport->ops->release_port)
|
||||
uport->ops->release_port(uport);
|
||||
|
||||
flags = UART_CONFIG_TYPE;
|
||||
|
@ -2897,7 +2897,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
|
|||
/*
|
||||
* Free the port IO and memory resources, if any.
|
||||
*/
|
||||
if (uport->type != PORT_UNKNOWN)
|
||||
if (uport->type != PORT_UNKNOWN && uport->ops->release_port)
|
||||
uport->ops->release_port(uport);
|
||||
kfree(uport->tty_groups);
|
||||
|
||||
|
|
Loading…
Reference in a new issue