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, 154 insertions, 0 deletions

diff --git a/security/selinux/genheaders.c b/security/selinux/genheaders.c
new file mode 100644
index 000000000..3834d7eb0
--- /dev/null
+++ b/security/selinux/genheaders.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <ctype.h>
+
+struct security_class_mapping {
+	const char *name;
+	const char *perms[sizeof(unsigned) * 8 + 1];
+};
+
+#include "classmap.h"
+#include "initial_sid_to_string.h"
+
+const char *progname;
+
+static void usage(void)
+{
+	printf("usage: %s flask.h av_permissions.h\n", progname);
+	exit(1);
+}
+
+static char *stoupperx(const char *s)
+{
+	char *s2 = strdup(s);
+	char *p;
+
+	if (!s2) {
+		fprintf(stderr, "%s:  out of memory\n", progname);
+		exit(3);
+	}
+
+	for (p = s2; *p; p++)
+		*p = toupper(*p);
+	return s2;
+}
+
+int main(int argc, char *argv[])
+{
+	int i, j;
+	int isids_len;
+	FILE *fout;
+
+	progname = argv[0];
+
+	if (argc < 3)
+		usage();
+
+	fout = fopen(argv[1], "w");
+	if (!fout) {
+		fprintf(stderr, "Could not open %s for writing:  %s\n",
+			argv[1], strerror(errno));
+		exit(2);
+	}
+
+	fprintf(fout, "/* This file is automatically generated.  Do not edit. */\n");
+	fprintf(fout, "#ifndef _SELINUX_FLASK_H_\n#define _SELINUX_FLASK_H_\n\n");
+
+	for (i = 0; secclass_map[i].name; i++) {
+		char *name = stoupperx(secclass_map[i].name);
+
+		fprintf(fout, "#define SECCLASS_%-39s %2d\n", name, i+1);
+		free(name);
+	}
+
+	fprintf(fout, "\n");
+
+	isids_len = sizeof(initial_sid_to_string) / sizeof(char *);
+	for (i = 1; i < isids_len; i++) {
+		const char *s = initial_sid_to_string[i];
+		if (s) {
+			char *sidname = stoupperx(s);
+
+			fprintf(fout, "#define SECINITSID_%-39s %2d\n", sidname, i);
+			free(sidname);
+		}
+	}
+	fprintf(fout, "\n#define SECINITSID_NUM %d\n", i-1);
+	fprintf(fout, "\nstatic inline bool security_is_socket_class(u16 kern_tclass)\n");
+	fprintf(fout, "{\n");
+	fprintf(fout, "\tbool sock = false;\n\n");
+	fprintf(fout, "\tswitch (kern_tclass) {\n");
+	for (i = 0; secclass_map[i].name; i++) {
+		static char s[] = "SOCKET";
+		int len, l;
+		char *name = stoupperx(secclass_map[i].name);
+
+		len = strlen(name);
+		l = sizeof(s) - 1;
+		if (len >= l && memcmp(name + len - l, s, l) == 0)
+			fprintf(fout, "\tcase SECCLASS_%s:\n", name);
+		free(name);
+	}
+	fprintf(fout, "\t\tsock = true;\n");
+	fprintf(fout, "\t\tbreak;\n");
+	fprintf(fout, "\tdefault:\n");
+	fprintf(fout, "\t\tbreak;\n");
+	fprintf(fout, "\t}\n\n");
+	fprintf(fout, "\treturn sock;\n");
+	fprintf(fout, "}\n");
+
+	fprintf(fout, "\n#endif\n");
+
+	if (fclose(fout) != 0) {
+		fprintf(stderr, "Could not successfully close %s:  %s\n",
+			argv[1], strerror(errno));
+		exit(4);
+	}
+
+	fout = fopen(argv[2], "w");
+	if (!fout) {
+		fprintf(stderr, "Could not open %s for writing:  %s\n",
+			argv[2], strerror(errno));
+		exit(5);
+	}
+
+	fprintf(fout, "/* This file is automatically generated.  Do not edit. */\n");
+	fprintf(fout, "#ifndef _SELINUX_AV_PERMISSIONS_H_\n#define _SELINUX_AV_PERMISSIONS_H_\n\n");
+
+	for (i = 0; secclass_map[i].name; i++) {
+		const struct security_class_mapping *map = &secclass_map[i];
+		int len;
+		char *name = stoupperx(map->name);
+
+		len = strlen(name);
+		for (j = 0; map->perms[j]; j++) {
+			char *permname;
+
+			if (j >= 32) {
+				fprintf(stderr, "Too many permissions to fit into an access vector at (%s, %s).\n",
+					map->name, map->perms[j]);
+				exit(5);
+			}
+			permname = stoupperx(map->perms[j]);
+			fprintf(fout, "#define %s__%-*s 0x%08xU\n", name,
+				39-len, permname, 1U<<j);
+			free(permname);
+		}
+		free(name);
+	}
+
+	fprintf(fout, "\n#endif\n");
+
+	if (fclose(fout) != 0) {
+		fprintf(stderr, "Could not successfully close %s:  %s\n",
+			argv[2], strerror(errno));
+		exit(6);
+	}
+
+	exit(0);
+}