summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorChen Gang <gang.chen@asianux.com>2012-12-27 15:51:31 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-01-15 23:00:44 -0800
commitb342dd512f7af0e0e14e29c3e1f863150cfc46ff (patch)
tree46deb7479d463bb04f426c46b38f12b64060bb01
parent074d35cebe96da07ac07f78118bc6a09e60350b5 (diff)
drivers/tty/serial: extern function which for release resource, need check pointer, before free it
for extern function uart_remove_one_port: need check pointer whether be NULL, before the main work. just like what the other extern function uart_add_one_port has done. uart_add_one_port and uart_remove_one_port are pair information: for the callers (such as drivers/tty/serial/jsm: jsm_tty.c, jsm_driver.c) they realy assume that: they still can call uart_remove_one_port, after uart_add_one_port failed we (as an extern function), have to understand it (just like kfree). Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/tty/serial/serial_core.c9
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index b5c4e64f299..ca98a3f65fe 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2643,6 +2643,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
{
struct uart_state *state = drv->state + uport->line;
struct tty_port *port = &state->port;
+ int ret = 0;
BUG_ON(in_interrupt());
@@ -2657,6 +2658,11 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
* succeeding while we shut down the port.
*/
mutex_lock(&port->mutex);
+ if (!state->uart_port) {
+ mutex_unlock(&port->mutex);
+ ret = -EINVAL;
+ goto out;
+ }
uport->flags |= UPF_DEAD;
mutex_unlock(&port->mutex);
@@ -2680,9 +2686,10 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
uport->type = PORT_UNKNOWN;
state->uart_port = NULL;
+out:
mutex_unlock(&port_mutex);
- return 0;
+ return ret;
}
/*