[PATCH 3.2 05/70] rfkill: copy the name into the rfkill struct

Ben Hutchings
2016-01-18T03:38:08Z

From: Johannes Berg <johannes.berg@intel.com>

commit b7bb110008607a915298bf0f47d25886ecb94477 upstream.

Some users of rfkill, like NFC and cfg80211, use a dynamic name when
allocating rfkill, in those cases dev_name(). Therefore, the pointer
passed to rfkill_alloc() might not be valid forever, I specifically
found the case that the rfkill name was quite obviously an invalid
pointer (or at least garbage) when the wiphy had been renamed.

Fix this by making a copy of the rfkill name in rfkill_alloc().

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/rfkill/core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/net/rfkill/core.c
+++ b/net/rfkill/core.c
@@ -50,7 +50,6 @@
struct rfkill {
spinlock_t lock;

- const char *name;
enum rfkill_type type;

unsigned long state;
@@ -74,6 +73,7 @@ struct rfkill {
struct delayed_work poll_work;
struct work_struct uevent_work;
struct work_struct sync_work;
+ char name[];
};
#define to_rfkill(d) container_of(d, struct rfkill, dev)

@@ -848,14 +848,14 @@ struct rfkill * __must_check rfkill_allo
if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
return NULL;

- rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
+ rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
if (!rfkill)
return NULL;

spin_lock_init(&rfkill->lock);
INIT_LIST_HEAD(&rfkill->node);
rfkill->type = type;
- rfkill->name = name;
+ strcpy(rfkill->name, name);
rfkill->ops = ops;
rfkill->data = ops_data;