openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

SELinux: Fix a RCU free problem with the netport cache 

The netport cache doesn't free resources in a manner which is safe or orderly.
This patch fixes this by adding in a missing call to rcu_dereference() in
sel_netport_insert() as well as some general cleanup throughout the file.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Paul Moore 2008-04-25 15:03:39 -04:00 committed by James Morris
parent a639e7ca8e
commit c9b7b97937
1 changed files with 18 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
security/selinux/netport.c
View File

@ -114,8 +114,7 @@ static struct sel_netport *sel_netport_find(u8 protocol, u16 pnum)
idx = sel_netport_hashfn(pnum);
list_for_each_entry_rcu(port, &sel_netport_hash[idx].list, list)
if (port->psec.port == pnum &&
port->psec.protocol == protocol)
if (port->psec.port == pnum && port->psec.protocol == protocol)
return port;
return NULL;
@ -126,11 +125,10 @@ static struct sel_netport *sel_netport_find(u8 protocol, u16 pnum)
* @port: the new port record
*
* Description:
* Add a new port record to the network address hash table. Returns zero on
* success, negative values on failure.
* Add a new port record to the network address hash table.
*
*/
static int sel_netport_insert(struct sel_netport *port)
static void sel_netport_insert(struct sel_netport *port)
{
unsigned int idx;
@ -140,13 +138,13 @@ static int sel_netport_insert(struct sel_netport *port)
list_add_rcu(&port->list, &sel_netport_hash[idx].list);
if (sel_netport_hash[idx].size == SEL_NETPORT_HASH_BKT_LIMIT) {
struct sel_netport *tail;
tail = list_entry(port->list.prev, struct sel_netport, list);
list_del_rcu(port->list.prev);
tail = list_entry(
rcu_dereference(sel_netport_hash[idx].list.prev),
struct sel_netport, list);
list_del_rcu(&tail->list);
call_rcu(&tail->rcu, sel_netport_free);
} else
sel_netport_hash[idx].size++;
return 0;
}
/**
@ -163,7 +161,7 @@ static int sel_netport_insert(struct sel_netport *port)
*/
static int sel_netport_sid_slow(u8 protocol, u16 pnum, u32 *sid)
{
int ret;
int ret = -ENOMEM;
struct sel_netport *port;
struct sel_netport *new = NULL;
@ -171,23 +169,20 @@ static int sel_netport_sid_slow(u8 protocol, u16 pnum, u32 *sid)
port = sel_netport_find(protocol, pnum);
if (port != NULL) {
*sid = port->psec.sid;
ret = 0;
goto out;
spin_unlock_bh(&sel_netport_lock);
return 0;
}
new = kzalloc(sizeof(*new), GFP_ATOMIC);
if (new == NULL) {
ret = -ENOMEM;
if (new == NULL)
goto out;
}
ret = security_port_sid(protocol, pnum, &new->psec.sid);
ret = security_port_sid(protocol, pnum, sid);
if (ret != 0)
goto out;
new->psec.port = pnum;
new->psec.protocol = protocol;
ret = sel_netport_insert(new);
if (ret != 0)
goto out;
*sid = new->psec.sid;
new->psec.sid = *sid;
sel_netport_insert(new);
out:
spin_unlock_bh(&sel_netport_lock);
@ -239,11 +234,12 @@ int sel_netport_sid(u8 protocol, u16 pnum, u32 *sid)
static void sel_netport_flush(void)
{
unsigned int idx;
struct sel_netport *port;
struct sel_netport *port, *port_tmp;
spin_lock_bh(&sel_netport_lock);
for (idx = 0; idx < SEL_NETPORT_HASH_SIZE; idx++) {
list_for_each_entry(port, &sel_netport_hash[idx].list, list) {
list_for_each_entry_safe(port, port_tmp,
&sel_netport_hash[idx].list, list) {
list_del_rcu(&port->list);
call_rcu(&port->rcu, sel_netport_free);
}