OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

net, llc: convert llc_sap.refcnt 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: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Reshetova, Elena 2017-07-04 15:52:56 +03:00 committed by David S. Miller
parent bf72acefeb
commit 58951dde05
2 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/net/llc.h
View File

@ -55,7 +55,7 @@ struct llc_sap {
unsigned char state; unsigned char state;
unsigned char p_bit; unsigned char p_bit;
unsigned char f_bit; unsigned char f_bit;
atomic_t refcnt; refcount_t refcnt;
int (*rcv_func)(struct sk_buff *skb, int (*rcv_func)(struct sk_buff *skb,
struct net_device *dev, struct net_device *dev,
struct packet_type *pt, struct packet_type *pt,
@ -113,14 +113,14 @@ struct llc_sap *llc_sap_open(unsigned char lsap,
struct net_device *orig_dev)); struct net_device *orig_dev));
static inline void llc_sap_hold(struct llc_sap *sap) static inline void llc_sap_hold(struct llc_sap *sap)
{ {
atomic_inc(&sap->refcnt); refcount_inc(&sap->refcnt);
} }
void llc_sap_close(struct llc_sap *sap); void llc_sap_close(struct llc_sap *sap);
static inline void llc_sap_put(struct llc_sap *sap) static inline void llc_sap_put(struct llc_sap *sap)
{ {
if (atomic_dec_and_test(&sap->refcnt)) if (refcount_dec_and_test(&sap->refcnt))
llc_sap_close(sap); llc_sap_close(sap);
} }

2
net/llc/llc_core.c
View File

@ -41,7 +41,7 @@ static struct llc_sap *llc_sap_alloc(void)
spin_lock_init(&sap->sk_lock); spin_lock_init(&sap->sk_lock);
for (i = 0; i < LLC_SK_LADDR_HASH_ENTRIES; i++) for (i = 0; i < LLC_SK_LADDR_HASH_ENTRIES; i++)
INIT_HLIST_NULLS_HEAD(&sap->sk_laddr_hash[i], i); INIT_HLIST_NULLS_HEAD(&sap->sk_laddr_hash[i], i);
atomic_set(&sap->refcnt, 1); refcount_set(&sap->refcnt, 1);
} }
return sap; return sap;
} }