security: Add hook to invalidate inode security labels
Add a hook to invalidate an inode's security label when the cached
information becomes invalid.
Add the new hook in selinux: set a flag when a security label becomes
invalid.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 4c48227..71969de 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1261,6 +1261,10 @@
* audit_rule_init.
* @rule contains the allocated rule
*
+ * @inode_invalidate_secctx:
+ * Notify the security module that it must revalidate the security context
+ * of an inode.
+ *
* @inode_notifysecctx:
* Notify the security module of what the security context of an inode
* should be. Initializes the incore security context managed by the
@@ -1516,6 +1520,7 @@
int (*secctx_to_secid)(const char *secdata, u32 seclen, u32 *secid);
void (*release_secctx)(char *secdata, u32 seclen);
+ void (*inode_invalidate_secctx)(struct inode *inode);
int (*inode_notifysecctx)(struct inode *inode, void *ctx, u32 ctxlen);
int (*inode_setsecctx)(struct dentry *dentry, void *ctx, u32 ctxlen);
int (*inode_getsecctx)(struct inode *inode, void **ctx, u32 *ctxlen);
@@ -1757,6 +1762,7 @@
struct list_head secid_to_secctx;
struct list_head secctx_to_secid;
struct list_head release_secctx;
+ struct list_head inode_invalidate_secctx;
struct list_head inode_notifysecctx;
struct list_head inode_setsecctx;
struct list_head inode_getsecctx;
diff --git a/include/linux/security.h b/include/linux/security.h
index e79149a..4824a4c 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -353,6 +353,7 @@
int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
void security_release_secctx(char *secdata, u32 seclen);
+void security_inode_invalidate_secctx(struct inode *inode);
int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
@@ -1093,6 +1094,10 @@
{
}
+static inline void security_inode_invalidate_secctx(struct inode *inode)
+{
+}
+
static inline int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
return -EOPNOTSUPP;
diff --git a/security/security.c b/security/security.c
index c5beb7e..e8ffd92 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1161,6 +1161,12 @@
}
EXPORT_SYMBOL(security_release_secctx);
+void security_inode_invalidate_secctx(struct inode *inode)
+{
+ call_void_hook(inode_invalidate_secctx, inode);
+}
+EXPORT_SYMBOL(security_inode_invalidate_secctx);
+
int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
return call_int_hook(inode_notifysecctx, 0, inode, ctx, ctxlen);
@@ -1763,6 +1769,8 @@
LIST_HEAD_INIT(security_hook_heads.secctx_to_secid),
.release_secctx =
LIST_HEAD_INIT(security_hook_heads.release_secctx),
+ .inode_invalidate_secctx =
+ LIST_HEAD_INIT(security_hook_heads.inode_invalidate_secctx),
.inode_notifysecctx =
LIST_HEAD_INIT(security_hook_heads.inode_notifysecctx),
.inode_setsecctx =
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 1dc0d79..ef3bd9d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -820,7 +820,7 @@
goto out;
root_isec->sid = rootcontext_sid;
- root_isec->initialized = 1;
+ root_isec->initialized = LABEL_INITIALIZED;
}
if (defcontext_sid) {
@@ -1308,11 +1308,11 @@
unsigned len = 0;
int rc = 0;
- if (isec->initialized)
+ if (isec->initialized == LABEL_INITIALIZED)
goto out;
mutex_lock(&isec->lock);
- if (isec->initialized)
+ if (isec->initialized == LABEL_INITIALIZED)
goto out_unlock;
sbsec = inode->i_sb->s_security;
@@ -1484,7 +1484,7 @@
break;
}
- isec->initialized = 1;
+ isec->initialized = LABEL_INITIALIZED;
out_unlock:
mutex_unlock(&isec->lock);
@@ -2790,7 +2790,7 @@
struct inode_security_struct *isec = inode->i_security;
isec->sclass = inode_mode_to_security_class(inode->i_mode);
isec->sid = newsid;
- isec->initialized = 1;
+ isec->initialized = LABEL_INITIALIZED;
}
if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
@@ -3089,7 +3089,7 @@
isec->sclass = inode_mode_to_security_class(inode->i_mode);
isec->sid = newsid;
- isec->initialized = 1;
+ isec->initialized = LABEL_INITIALIZED;
return;
}
@@ -3183,7 +3183,7 @@
isec->sclass = inode_mode_to_security_class(inode->i_mode);
isec->sid = newsid;
- isec->initialized = 1;
+ isec->initialized = LABEL_INITIALIZED;
return 0;
}
@@ -3761,7 +3761,7 @@
u32 sid = task_sid(p);
isec->sid = sid;
- isec->initialized = 1;
+ isec->initialized = LABEL_INITIALIZED;
}
/* Returns error only if unable to parse addresses */
@@ -4092,7 +4092,7 @@
return err;
}
- isec->initialized = 1;
+ isec->initialized = LABEL_INITIALIZED;
if (sock->sk) {
sksec = sock->sk->sk_security;
@@ -4283,7 +4283,7 @@
isec = inode_security(SOCK_INODE(sock));
newisec->sclass = isec->sclass;
newisec->sid = isec->sid;
- newisec->initialized = 1;
+ newisec->initialized = LABEL_INITIALIZED;
return 0;
}
@@ -5775,6 +5775,15 @@
kfree(secdata);
}
+static void selinux_inode_invalidate_secctx(struct inode *inode)
+{
+ struct inode_security_struct *isec = inode->i_security;
+
+ mutex_lock(&isec->lock);
+ isec->initialized = LABEL_INVALID;
+ mutex_unlock(&isec->lock);
+}
+
/*
* called with inode->i_mutex locked
*/
@@ -6006,6 +6015,7 @@
LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
+ LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 81fa718..a2ae054 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -37,6 +37,12 @@
u32 sockcreate_sid; /* fscreate SID */
};
+enum label_initialized {
+ LABEL_MISSING, /* not initialized */
+ LABEL_INITIALIZED, /* inizialized */
+ LABEL_INVALID /* invalid */
+};
+
struct inode_security_struct {
struct inode *inode; /* back pointer to inode object */
union {