From 5b902d6f97f573fde911338e5d943e6b07fac7f9 Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Thu, 3 Sep 2015 23:59:50 +0100 Subject: [PATCH] device property: Don't overwrite addr when failing in device_get_mac_address The function device_get_mac_address is trying different property names in order to get the mac address. To check the return value, the variable addr (which contain the buffer pass by the caller) will be re-used. This means that if the previous property is not found, the next property will be read using a NULL buffer. Therefore it's only possible to retrieve the mac if node contains a property "mac-address". Fix it by using a temporary buffer for the return value. This has been introduced by commit 4c96b7dc0d393f12c17e0d81db15aa4a820a6ab3 "Add a matching set of device_ functions for determining mac/phy" Signed-off-by: Julien Grall Cc: Jeremy Linton Cc: David S. Miller Reviewed-by: Jeremy Linton Signed-off-by: David S. Miller --- drivers/base/property.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/base/property.c b/drivers/base/property.c index ff03f2348f77..2d75366c61e0 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -611,13 +611,15 @@ static void *device_get_mac_addr(struct device *dev, */ void *device_get_mac_address(struct device *dev, char *addr, int alen) { - addr = device_get_mac_addr(dev, "mac-address", addr, alen); - if (addr) - return addr; + char *res; - addr = device_get_mac_addr(dev, "local-mac-address", addr, alen); - if (addr) - return addr; + res = device_get_mac_addr(dev, "mac-address", addr, alen); + if (res) + return res; + + res = device_get_mac_addr(dev, "local-mac-address", addr, alen); + if (res) + return res; return device_get_mac_addr(dev, "address", addr, alen); }