From: Paul Moore paul@paul-moore.com
[ Upstream commit d8db60cb23e49a92cf8cada3297395c7fa50fdf8 ]
Fix avc_insert() to call avc_node_kill() if we've already allocated an AVC node and the code fails to insert the node in the cache.
Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls") Reported-by: rsiddoji@codeaurora.org Suggested-by: Stephen Smalley sds@tycho.nsa.gov Acked-by: Stephen Smalley sds@tycho.nsa.gov Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- security/selinux/avc.c | 51 ++++++++++++++++++++++++-------------------------- 1 file changed, 24 insertions(+), 27 deletions(-)
diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 0622cae..83eef39 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -689,40 +689,37 @@ static struct avc_node *avc_insert(struct selinux_avc *avc, struct avc_node *pos, *node = NULL; int hvalue; unsigned long flag; + spinlock_t *lock; + struct hlist_head *head;
if (avc_latest_notif_update(avc, avd->seqno, 1)) - goto out; + return NULL;
node = avc_alloc_node(avc); - if (node) { - struct hlist_head *head; - spinlock_t *lock; - int rc = 0; - - hvalue = avc_hash(ssid, tsid, tclass); - avc_node_populate(node, ssid, tsid, tclass, avd); - rc = avc_xperms_populate(node, xp_node); - if (rc) { - kmem_cache_free(avc_node_cachep, node); - return NULL; - } - head = &avc->avc_cache.slots[hvalue]; - lock = &avc->avc_cache.slots_lock[hvalue]; + if (!node) + return NULL;
- spin_lock_irqsave(lock, flag); - hlist_for_each_entry(pos, head, list) { - if (pos->ae.ssid == ssid && - pos->ae.tsid == tsid && - pos->ae.tclass == tclass) { - avc_node_replace(avc, node, pos); - goto found; - } + avc_node_populate(node, ssid, tsid, tclass, avd); + if (avc_xperms_populate(node, xp_node)) { + avc_node_kill(avc, node); + return NULL; + } + + hvalue = avc_hash(ssid, tsid, tclass); + head = &avc->avc_cache.slots[hvalue]; + lock = &avc->avc_cache.slots_lock[hvalue]; + spin_lock_irqsave(lock, flag); + hlist_for_each_entry(pos, head, list) { + if (pos->ae.ssid == ssid && + pos->ae.tsid == tsid && + pos->ae.tclass == tclass) { + avc_node_replace(avc, node, pos); + goto found; } - hlist_add_head_rcu(&node->list, head); -found: - spin_unlock_irqrestore(lock, flag); } -out: + hlist_add_head_rcu(&node->list, head); +found: + spin_unlock_irqrestore(lock, flag); return node; }