extcon: return error code on failure

Function get_zeroed_page() returns a NULL pointer if there is no enough
memory. In function extcon_sync(), it returns 0 if the call to
get_zeroed_page() fails. The return value 0 indicates success in the
context, which is incosistent with the execution status. This patch
fixes the bug by returning -ENOMEM.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=188611

Signed-off-by: Pan Bian <bianpan2016@163.com>
Fixes: a580982f0836e
Cc: stable <stable@vger.kernel.org>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

path: root/include/net/esp.h

#ifndef _NET_ESP_H
#define _NET_ESP_H

#include <linux/skbuff.h>

struct ip_esp_hdr;

static inline struct ip_esp_hdr *ip_esp_hdr(const struct sk_buff *skb)
{
	return (struct ip_esp_hdr *)skb_transport_header(skb);
}

#endif