Commit 39f25d42 authored by Reshetova, Elena's avatar Reshetova, Elena Committed by David S. Miller
Browse files

net, ax25: convert ax25_route.refcount from atomic_t to refcount_t 



refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: default avatarElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: default avatarHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarDavid Windsor <dwindsor@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 07f2282f

include/net/ax25.h

+3 −3
Original line number Original line Diff line number Diff line
@@ -185,7 +185,7 @@ typedef struct { 




typedef struct ax25_route {

typedef struct ax25_route {

	struct ax25_route	*next;

	struct ax25_route	*next;

	atomic_t		refcount;

	refcount_t		refcount;

	ax25_address		callsign;

	ax25_address		callsign;

	struct net_device	*dev;

	struct net_device	*dev;

	ax25_digi		*digipeat;

	ax25_digi		*digipeat;
@@ -194,14 +194,14 @@ typedef struct ax25_route { 




static inline void ax25_hold_route(ax25_route *ax25_rt)

static inline void ax25_hold_route(ax25_route *ax25_rt)

{

{

	atomic_inc(&ax25_rt->refcount);

	refcount_inc(&ax25_rt->refcount);

}

}





void __ax25_put_route(ax25_route *ax25_rt);

void __ax25_put_route(ax25_route *ax25_rt);





static inline void ax25_put_route(ax25_route *ax25_rt)

static inline void ax25_put_route(ax25_route *ax25_rt)

{

{

	if (atomic_dec_and_test(&ax25_rt->refcount))

	if (refcount_dec_and_test(&ax25_rt->refcount))

		__ax25_put_route(ax25_rt);

		__ax25_put_route(ax25_rt);

}

}

net/ax25/ax25_route.c

+1 −1
Original line number Original line Diff line number Diff line
@@ -114,7 +114,7 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) 
		return -ENOMEM;

		return -ENOMEM;

	}

	}





	atomic_set(&ax25_rt->refcount, 1);

	refcount_set(&ax25_rt->refcount, 1);

	ax25_rt->callsign     = route->dest_addr;

	ax25_rt->callsign     = route->dest_addr;

	ax25_rt->dev          = ax25_dev->dev;

	ax25_rt->dev          = ax25_dev->dev;

	ax25_rt->digipeat     = NULL;

	ax25_rt->digipeat     = NULL;

CRA Git | Maintained and supported by SUSTech CRA and CCSE