tty: ipwireless: Replace GFP_ATOMIC with GFP_KERNEL in ipwireless_network_create
authorJia-Ju Bai <baijiaju1990@gmail.com>
Tue, 10 Apr 2018 08:31:46 +0000 (16:31 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 23 Apr 2018 08:57:06 +0000 (10:57 +0200)
ipwireless_network_create() is never called in atomic context.

The call chain ending up at ipwireless_network_create() is:
[1] ipwireless_network_create() <- config_ipwireless() <-
ipwireless_attach()
ipwireless_attach() is only set as ".probe" in struct pcmcia_driver.

Despite never getting called from atomic context,
ipwireless_network_create() calls kzalloc() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/ipwireless/network.c

index 695439c..cf20616 100644 (file)
@@ -416,7 +416,7 @@ void ipwireless_network_packet_received(struct ipw_network *network,
 struct ipw_network *ipwireless_network_create(struct ipw_hardware *hw)
 {
        struct ipw_network *network =
-               kzalloc(sizeof(struct ipw_network), GFP_ATOMIC);
+               kzalloc(sizeof(struct ipw_network), GFP_KERNEL);
 
        if (!network)
                return NULL;