diff options
Diffstat (limited to 'security/selinux/hooks.c')
-rw-r--r-- | security/selinux/hooks.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9f6380ec1305..5b3db436814d 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -218,6 +218,14 @@ static int inode_alloc_security(struct inode *inode) return 0; } +static void inode_free_rcu(struct rcu_head *head) +{ + struct inode_security_struct *isec; + + isec = container_of(head, struct inode_security_struct, rcu); + kmem_cache_free(sel_inode_cache, isec); +} + static void inode_free_security(struct inode *inode) { struct inode_security_struct *isec = inode->i_security; @@ -228,8 +236,16 @@ static void inode_free_security(struct inode *inode) list_del_init(&isec->list); spin_unlock(&sbsec->isec_lock); - inode->i_security = NULL; - kmem_cache_free(sel_inode_cache, isec); + /* + * The inode may still be referenced in a path walk and + * a call to selinux_inode_permission() can be made + * after inode_free_security() is called. Ideally, the VFS + * wouldn't do this, but fixing that is a much harder + * job. For now, simply free the i_security via RCU, and + * leave the current inode->i_security pointer intact. + * The inode will be freed after the RCU grace period too. + */ + call_rcu(&isec->rcu, inode_free_rcu); } static int file_alloc_security(struct file *file) |