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-rw-r--r--include/linux/selinux.h45
-rw-r--r--net/netfilter/xt_SECMARK.c13
-rw-r--r--security/selinux/exports.c20
-rw-r--r--security/selinux/hooks.c46
-rw-r--r--security/selinux/include/xfrm.h12
-rw-r--r--security/selinux/xfrm.c18
6 files changed, 132 insertions, 22 deletions
diff --git a/include/linux/selinux.h b/include/linux/selinux.h
index 6080f73fc85..8c2cc4c0252 100644
--- a/include/linux/selinux.h
+++ b/include/linux/selinux.h
@@ -120,16 +120,35 @@ void selinux_get_task_sid(struct task_struct *tsk, u32 *sid);
int selinux_string_to_sid(char *str, u32 *sid);
/**
- * selinux_relabel_packet_permission - check permission to relabel a packet
- * @sid: ID value to be applied to network packet (via SECMARK, most likely)
+ * selinux_secmark_relabel_packet_permission - secmark permission check
+ * @sid: SECMARK ID value to be applied to network packet
*
- * Returns 0 if the current task is allowed to label packets with the
- * supplied security ID. Note that it is implicit that the packet is always
- * being relabeled from the default unlabled value, and that the access
- * control decision is made in the AVC.
+ * Returns 0 if the current task is allowed to set the SECMARK label of
+ * packets with the supplied security ID. Note that it is implicit that
+ * the packet is always being relabeled from the default unlabeled value,
+ * and that the access control decision is made in the AVC.
*/
-int selinux_relabel_packet_permission(u32 sid);
+int selinux_secmark_relabel_packet_permission(u32 sid);
+/**
+ * selinux_secmark_refcount_inc - increments the secmark use counter
+ *
+ * SELinux keeps track of the current SECMARK targets in use so it knows
+ * when to apply SECMARK label access checks to network packets. This
+ * function incements this reference count to indicate that a new SECMARK
+ * target has been configured.
+ */
+void selinux_secmark_refcount_inc(void);
+
+/**
+ * selinux_secmark_refcount_dec - decrements the secmark use counter
+ *
+ * SELinux keeps track of the current SECMARK targets in use so it knows
+ * when to apply SECMARK label access checks to network packets. This
+ * function decements this reference count to indicate that one of the
+ * existing SECMARK targets has been removed/flushed.
+ */
+void selinux_secmark_refcount_dec(void);
#else
static inline int selinux_audit_rule_init(u32 field, u32 op,
@@ -184,11 +203,21 @@ static inline int selinux_string_to_sid(const char *str, u32 *sid)
return 0;
}
-static inline int selinux_relabel_packet_permission(u32 sid)
+static inline int selinux_secmark_relabel_packet_permission(u32 sid)
{
return 0;
}
+static inline void selinux_secmark_refcount_inc(void)
+{
+ return;
+}
+
+static inline void selinux_secmark_refcount_dec(void)
+{
+ return;
+}
+
#endif /* CONFIG_SECURITY_SELINUX */
#endif /* _LINUX_SELINUX_H */
diff --git a/net/netfilter/xt_SECMARK.c b/net/netfilter/xt_SECMARK.c
index b11b3ecbb39..7708e2084ce 100644
--- a/net/netfilter/xt_SECMARK.c
+++ b/net/netfilter/xt_SECMARK.c
@@ -72,12 +72,13 @@ static bool checkentry_selinux(struct xt_secmark_target_info *info)
return false;
}
- err = selinux_relabel_packet_permission(sel->selsid);
+ err = selinux_secmark_relabel_packet_permission(sel->selsid);
if (err) {
printk(KERN_INFO PFX "unable to obtain relabeling permission\n");
return false;
}
+ selinux_secmark_refcount_inc();
return true;
}
@@ -110,11 +111,20 @@ secmark_tg_check(const char *tablename, const void *entry,
return true;
}
+void secmark_tg_destroy(const struct xt_target *target, void *targinfo)
+{
+ switch (mode) {
+ case SECMARK_MODE_SEL:
+ selinux_secmark_refcount_dec();
+ }
+}
+
static struct xt_target secmark_tg_reg[] __read_mostly = {
{
.name = "SECMARK",
.family = AF_INET,
.checkentry = secmark_tg_check,
+ .destroy = secmark_tg_destroy,
.target = secmark_tg,
.targetsize = sizeof(struct xt_secmark_target_info),
.table = "mangle",
@@ -124,6 +134,7 @@ static struct xt_target secmark_tg_reg[] __read_mostly = {
.name = "SECMARK",
.family = AF_INET6,
.checkentry = secmark_tg_check,
+ .destroy = secmark_tg_destroy,
.target = secmark_tg,
.targetsize = sizeof(struct xt_secmark_target_info),
.table = "mangle",
diff --git a/security/selinux/exports.c b/security/selinux/exports.c
index b6f96943be1..87d2bb3ea35 100644
--- a/security/selinux/exports.c
+++ b/security/selinux/exports.c
@@ -17,10 +17,14 @@
#include <linux/selinux.h>
#include <linux/fs.h>
#include <linux/ipc.h>
+#include <asm/atomic.h>
#include "security.h"
#include "objsec.h"
+/* SECMARK reference count */
+extern atomic_t selinux_secmark_refcount;
+
int selinux_sid_to_string(u32 sid, char **ctx, u32 *ctxlen)
{
if (selinux_enabled)
@@ -74,7 +78,7 @@ int selinux_string_to_sid(char *str, u32 *sid)
}
EXPORT_SYMBOL_GPL(selinux_string_to_sid);
-int selinux_relabel_packet_permission(u32 sid)
+int selinux_secmark_relabel_packet_permission(u32 sid)
{
if (selinux_enabled) {
struct task_security_struct *tsec = current->security;
@@ -84,4 +88,16 @@ int selinux_relabel_packet_permission(u32 sid)
}
return 0;
}
-EXPORT_SYMBOL_GPL(selinux_relabel_packet_permission);
+EXPORT_SYMBOL_GPL(selinux_secmark_relabel_packet_permission);
+
+void selinux_secmark_refcount_inc(void)
+{
+ atomic_inc(&selinux_secmark_refcount);
+}
+EXPORT_SYMBOL_GPL(selinux_secmark_refcount_inc);
+
+void selinux_secmark_refcount_dec(void)
+{
+ atomic_dec(&selinux_secmark_refcount);
+}
+EXPORT_SYMBOL_GPL(selinux_secmark_refcount_dec);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index bfe9a05db3a..6156241c877 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -51,8 +51,10 @@
#include <net/ip.h> /* for local_port_range[] */
#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
#include <net/net_namespace.h>
+#include <net/netlabel.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
+#include <asm/atomic.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h> /* for network interface checks */
@@ -91,6 +93,9 @@ extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
extern int selinux_compat_net;
extern struct security_operations *security_ops;
+/* SECMARK reference count */
+atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
+
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
int selinux_enforcing = 0;
@@ -157,6 +162,21 @@ getsecurity_exit:
return len;
}
+/**
+ * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
+ *
+ * Description:
+ * This function checks the SECMARK reference counter to see if any SECMARK
+ * targets are currently configured, if the reference counter is greater than
+ * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
+ * enabled, false (0) if SECMARK is disabled.
+ *
+ */
+static int selinux_secmark_enabled(void)
+{
+ return (atomic_read(&selinux_secmark_refcount) > 0);
+}
+
/* Allocate and free functions for each kind of security blob. */
static int task_alloc_security(struct task_struct *task)
@@ -3931,7 +3951,6 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
struct sk_security_struct *sksec = sk->sk_security;
u16 family = sk->sk_family;
u32 sk_sid = sksec->sid;
- u32 peer_sid;
struct avc_audit_data ad;
char *addrp;
@@ -3957,15 +3976,24 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
return selinux_sock_rcv_skb_compat(sk, skb, &ad,
family, addrp);
- err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
- PACKET__RECV, &ad);
- if (err)
- return err;
+ if (selinux_secmark_enabled()) {
+ err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
+ PACKET__RECV, &ad);
+ if (err)
+ return err;
+ }
- err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
- if (err)
- return err;
- return avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, PEER__RECV, &ad);
+ if (netlbl_enabled() || selinux_xfrm_enabled()) {
+ u32 peer_sid;
+
+ err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
+ if (err)
+ return err;
+ err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
+ PEER__RECV, &ad);
+ }
+
+ return err;
}
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h
index 31929e39f5c..36b0510efa7 100644
--- a/security/selinux/include/xfrm.h
+++ b/security/selinux/include/xfrm.h
@@ -32,6 +32,13 @@ static inline struct inode_security_struct *get_sock_isec(struct sock *sk)
}
#ifdef CONFIG_SECURITY_NETWORK_XFRM
+extern atomic_t selinux_xfrm_refcount;
+
+static inline int selinux_xfrm_enabled(void)
+{
+ return (atomic_read(&selinux_xfrm_refcount) > 0);
+}
+
int selinux_xfrm_sock_rcv_skb(u32 sid, struct sk_buff *skb,
struct avc_audit_data *ad);
int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb,
@@ -43,6 +50,11 @@ static inline void selinux_xfrm_notify_policyload(void)
atomic_inc(&flow_cache_genid);
}
#else
+static inline int selinux_xfrm_enabled(void)
+{
+ return 0;
+}
+
static inline int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb,
struct avc_audit_data *ad)
{
diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c
index e0760396903..7e158205d08 100644
--- a/security/selinux/xfrm.c
+++ b/security/selinux/xfrm.c
@@ -46,11 +46,14 @@
#include <net/checksum.h>
#include <net/udp.h>
#include <asm/semaphore.h>
+#include <asm/atomic.h>
#include "avc.h"
#include "objsec.h"
#include "xfrm.h"
+/* Labeled XFRM instance counter */
+atomic_t selinux_xfrm_refcount = ATOMIC_INIT(0);
/*
* Returns true if an LSM/SELinux context
@@ -293,6 +296,9 @@ int selinux_xfrm_policy_alloc(struct xfrm_policy *xp,
BUG_ON(!uctx);
err = selinux_xfrm_sec_ctx_alloc(&xp->security, uctx, 0);
+ if (err == 0)
+ atomic_inc(&selinux_xfrm_refcount);
+
return err;
}
@@ -340,10 +346,13 @@ int selinux_xfrm_policy_delete(struct xfrm_policy *xp)
struct xfrm_sec_ctx *ctx = xp->security;
int rc = 0;
- if (ctx)
+ if (ctx) {
rc = avc_has_perm(tsec->sid, ctx->ctx_sid,
SECCLASS_ASSOCIATION,
ASSOCIATION__SETCONTEXT, NULL);
+ if (rc == 0)
+ atomic_dec(&selinux_xfrm_refcount);
+ }
return rc;
}
@@ -360,6 +369,8 @@ int selinux_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *uct
BUG_ON(!x);
err = selinux_xfrm_sec_ctx_alloc(&x->security, uctx, secid);
+ if (err == 0)
+ atomic_inc(&selinux_xfrm_refcount);
return err;
}
@@ -382,10 +393,13 @@ int selinux_xfrm_state_delete(struct xfrm_state *x)
struct xfrm_sec_ctx *ctx = x->security;
int rc = 0;
- if (ctx)
+ if (ctx) {
rc = avc_has_perm(tsec->sid, ctx->ctx_sid,
SECCLASS_ASSOCIATION,
ASSOCIATION__SETCONTEXT, NULL);
+ if (rc == 0)
+ atomic_dec(&selinux_xfrm_refcount);
+ }
return rc;
}