ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 94 insertions, 0 deletions

diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h
new file mode 100644
index 000000000..de485556a
--- /dev/null
+++ b/security/selinux/include/xfrm.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * SELinux support for the XFRM LSM hooks
+ *
+ * Author : Trent Jaeger, <jaegert@us.ibm.com>
+ * Updated : Venkat Yekkirala, <vyekkirala@TrustedCS.com>
+ */
+
+#ifndef _SELINUX_XFRM_H_
+#define _SELINUX_XFRM_H_
+
+#include <linux/lsm_audit.h>
+#include <net/flow.h>
+#include <net/xfrm.h>
+
+int selinux_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
+			      struct xfrm_user_sec_ctx *uctx, gfp_t gfp);
+int selinux_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
+			      struct xfrm_sec_ctx **new_ctxp);
+void selinux_xfrm_policy_free(struct xfrm_sec_ctx *ctx);
+int selinux_xfrm_policy_delete(struct xfrm_sec_ctx *ctx);
+int selinux_xfrm_state_alloc(struct xfrm_state *x,
+			     struct xfrm_user_sec_ctx *uctx);
+int selinux_xfrm_state_alloc_acquire(struct xfrm_state *x,
+				     struct xfrm_sec_ctx *polsec, u32 secid);
+void selinux_xfrm_state_free(struct xfrm_state *x);
+int selinux_xfrm_state_delete(struct xfrm_state *x);
+int selinux_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid);
+int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x,
+				      struct xfrm_policy *xp,
+				      const struct flowi_common *flic);
+
+#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 sk_sid, struct sk_buff *skb,
+			      struct common_audit_data *ad);
+int selinux_xfrm_postroute_last(u32 sk_sid, struct sk_buff *skb,
+				struct common_audit_data *ad, u8 proto);
+int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid, int ckall);
+int selinux_xfrm_skb_sid(struct sk_buff *skb, u32 *sid);
+
+static inline void selinux_xfrm_notify_policyload(void)
+{
+	struct net *net;
+
+	down_read(&net_rwsem);
+	for_each_net(net)
+		rt_genid_bump_all(net);
+	up_read(&net_rwsem);
+}
+#else
+static inline int selinux_xfrm_enabled(void)
+{
+	return 0;
+}
+
+static inline int selinux_xfrm_sock_rcv_skb(u32 sk_sid, struct sk_buff *skb,
+					    struct common_audit_data *ad)
+{
+	return 0;
+}
+
+static inline int selinux_xfrm_postroute_last(u32 sk_sid, struct sk_buff *skb,
+					      struct common_audit_data *ad,
+					      u8 proto)
+{
+	return 0;
+}
+
+static inline int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid,
+					      int ckall)
+{
+	*sid = SECSID_NULL;
+	return 0;
+}
+
+static inline void selinux_xfrm_notify_policyload(void)
+{
+}
+
+static inline int selinux_xfrm_skb_sid(struct sk_buff *skb, u32 *sid)
+{
+	*sid = SECSID_NULL;
+	return 0;
+}
+#endif
+
+#endif /* _SELINUX_XFRM_H_ */