[PATCH 12/17] net: convert unix_address.refcnt from atomic_t to refcount_t

[Elena Reshetova]

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 
Signed-off-by: Hans Liljestrand 
Signed-off-by: Kees Cook 
Signed-off-by: David Windsor 
---
 include/net/af_unix.h | 3 ++-
 net/unix/af_unix.c| 8 
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index fd60ecc..3a385e4 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -4,6 +4,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 
 void unix_inflight(struct user_struct *user, struct file *fp);
@@ -21,7 +22,7 @@ extern spinlock_t unix_table_lock;
 extern struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE];
 
 struct unix_address {
-   atomic_trefcnt;
+   refcount_t  refcnt;
int len;
unsigned inthash;
struct sockaddr_un name[0];
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index c885254..b9ee766 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -212,7 +212,7 @@ EXPORT_SYMBOL_GPL(unix_peer_get);
 
 static inline void unix_release_addr(struct unix_address *addr)
 {
-   if (atomic_dec_and_test(>refcnt))
+   if (refcount_dec_and_test(>refcnt))
kfree(addr);
 }
 
@@ -864,7 +864,7 @@ static int unix_autobind(struct socket *sock)
goto out;
 
addr->name->sun_family = AF_UNIX;
-   atomic_set(>refcnt, 1);
+   refcount_set(>refcnt, 1);
 
 retry:
addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + 
sizeof(short);
@@ -1040,7 +1040,7 @@ static int unix_bind(struct socket *sock, struct sockaddr 
*uaddr, int addr_len)
memcpy(addr->name, sunaddr, addr_len);
addr->len = addr_len;
addr->hash = hash ^ sk->sk_type;
-   atomic_set(>refcnt, 1);
+   refcount_set(>refcnt, 1);
 
if (sun_path[0]) {
addr->hash = UNIX_HASH_SIZE;
@@ -1335,7 +1335,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
 
/* copy address information from listening to new sock*/
if (otheru->addr) {
-   atomic_inc(>addr->refcnt);
+   refcount_inc(>addr->refcnt);
newu->addr = otheru->addr;
}
if (otheru->path.dentry) {
-- 
2.7.4

[PATCH 12/17] net: convert unix_address.refcnt from atomic_t to refcount_t

[Elena Reshetova]

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 
Signed-off-by: Hans Liljestrand 
Signed-off-by: Kees Cook 
Signed-off-by: David Windsor 
---
 include/net/af_unix.h | 3 ++-
 net/unix/af_unix.c| 8 
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index fd60ecc..3a385e4 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -4,6 +4,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 
 void unix_inflight(struct user_struct *user, struct file *fp);
@@ -21,7 +22,7 @@ extern spinlock_t unix_table_lock;
 extern struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE];
 
 struct unix_address {
-   atomic_trefcnt;
+   refcount_t  refcnt;
int len;
unsigned inthash;
struct sockaddr_un name[0];
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index c885254..b9ee766 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -212,7 +212,7 @@ EXPORT_SYMBOL_GPL(unix_peer_get);
 
 static inline void unix_release_addr(struct unix_address *addr)
 {
-   if (atomic_dec_and_test(>refcnt))
+   if (refcount_dec_and_test(>refcnt))
kfree(addr);
 }
 
@@ -864,7 +864,7 @@ static int unix_autobind(struct socket *sock)
goto out;
 
addr->name->sun_family = AF_UNIX;
-   atomic_set(>refcnt, 1);
+   refcount_set(>refcnt, 1);
 
 retry:
addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + 
sizeof(short);
@@ -1040,7 +1040,7 @@ static int unix_bind(struct socket *sock, struct sockaddr 
*uaddr, int addr_len)
memcpy(addr->name, sunaddr, addr_len);
addr->len = addr_len;
addr->hash = hash ^ sk->sk_type;
-   atomic_set(>refcnt, 1);
+   refcount_set(>refcnt, 1);
 
if (sun_path[0]) {
addr->hash = UNIX_HASH_SIZE;
@@ -1335,7 +1335,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
 
/* copy address information from listening to new sock*/
if (otheru->addr) {
-   atomic_inc(>addr->refcnt);
+   refcount_inc(>addr->refcnt);
newu->addr = otheru->addr;
}
if (otheru->path.dentry) {
-- 
2.7.4

[PATCH 12/17] net: convert unix_address.refcnt from atomic_t to refcount_t

[Elena Reshetova]

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 
Signed-off-by: Hans Liljestrand 
Signed-off-by: Kees Cook 
Signed-off-by: David Windsor 
---
 include/net/af_unix.h | 3 ++-
 net/unix/af_unix.c| 8 
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index fd60ecc..3a385e4 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -4,6 +4,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 
 void unix_inflight(struct user_struct *user, struct file *fp);
@@ -21,7 +22,7 @@ extern spinlock_t unix_table_lock;
 extern struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE];
 
 struct unix_address {
-   atomic_trefcnt;
+   refcount_t  refcnt;
int len;
unsigned inthash;
struct sockaddr_un name[0];
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index e9f8102..5e2a402 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -212,7 +212,7 @@ EXPORT_SYMBOL_GPL(unix_peer_get);
 
 static inline void unix_release_addr(struct unix_address *addr)
 {
-   if (atomic_dec_and_test(>refcnt))
+   if (refcount_dec_and_test(>refcnt))
kfree(addr);
 }
 
@@ -861,7 +861,7 @@ static int unix_autobind(struct socket *sock)
goto out;
 
addr->name->sun_family = AF_UNIX;
-   atomic_set(>refcnt, 1);
+   refcount_set(>refcnt, 1);
 
 retry:
addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + 
sizeof(short);
@@ -1036,7 +1036,7 @@ static int unix_bind(struct socket *sock, struct sockaddr 
*uaddr, int addr_len)
memcpy(addr->name, sunaddr, addr_len);
addr->len = addr_len;
addr->hash = hash ^ sk->sk_type;
-   atomic_set(>refcnt, 1);
+   refcount_set(>refcnt, 1);
 
if (sun_path[0]) {
addr->hash = UNIX_HASH_SIZE;
@@ -1327,7 +1327,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
 
/* copy address information from listening to new sock*/
if (otheru->addr) {
-   atomic_inc(>addr->refcnt);
+   refcount_inc(>addr->refcnt);
newu->addr = otheru->addr;
}
if (otheru->path.dentry) {
-- 
2.7.4