summaryrefslogtreecommitdiffstats
path: root/Add-sysrq-option-to-disable-secure-boot-mode.patch
blob: d40605af611b2e557c7705384d7f30ac8a22429b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
From 97066041b4f7b3ce41191110f5f47b4cd69d81fa Mon Sep 17 00:00:00 2001
From: Kyle McMartin <kyle@redhat.com>
Date: Fri, 30 Aug 2013 09:28:51 -0400
Subject: [PATCH] Add sysrq option to disable secure boot mode

Bugzilla: N/A
Upstream-status: Fedora mustard
---
 arch/x86/kernel/setup.c     | 36 ++++++++++++++++++++++++++++++++++++
 drivers/input/misc/uinput.c |  1 +
 drivers/tty/sysrq.c         | 19 +++++++++++++------
 include/linux/input.h       |  5 +++++
 include/linux/sysrq.h       |  8 +++++++-
 kernel/debug/kdb/kdb_main.c |  2 +-
 kernel/module.c             |  4 ++--
 7 files changed, 65 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index fb282ff6a802..d291d16ba257 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -70,6 +70,11 @@
 #include <linux/tboot.h>
 #include <linux/jiffies.h>
 
+#include <linux/fips.h>
+#include <linux/cred.h>
+#include <linux/sysrq.h>
+#include <linux/init_task.h>
+
 #include <video/edid.h>
 
 #include <asm/mtrr.h>
@@ -1268,6 +1273,37 @@ void __init i386_reserve_resources(void)
 
 #endif /* CONFIG_X86_32 */
 
+#ifdef CONFIG_MAGIC_SYSRQ
+#ifdef CONFIG_MODULE_SIG
+extern bool sig_enforce;
+#endif
+
+static void sysrq_handle_secure_boot(int key)
+{
+	if (!efi_enabled(EFI_SECURE_BOOT))
+		return;
+
+	pr_info("Secure boot disabled\n");
+#ifdef CONFIG_MODULE_SIG
+	sig_enforce = fips_enabled;
+#endif
+}
+static struct sysrq_key_op secure_boot_sysrq_op = {
+	.handler	=	sysrq_handle_secure_boot,
+	.help_msg	=	"unSB(x)",
+	.action_msg	=	"Disabling Secure Boot restrictions",
+	.enable_mask	=	SYSRQ_DISABLE_USERSPACE,
+};
+static int __init secure_boot_sysrq(void)
+{
+	if (efi_enabled(EFI_SECURE_BOOT))
+		register_sysrq_key('x', &secure_boot_sysrq_op);
+	return 0;
+}
+late_initcall(secure_boot_sysrq);
+#endif /*CONFIG_MAGIC_SYSRQ*/
+
+
 static struct notifier_block kernel_offset_notifier = {
 	.notifier_call = dump_kernel_offset
 };
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index 421e29e4cd81..61c1eb97806c 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -366,6 +366,7 @@ static int uinput_allocate_device(struct uinput_device *udev)
 	if (!udev->dev)
 		return -ENOMEM;
 
+	udev->dev->flags |= INPUTDEV_FLAGS_SYNTHETIC;
 	udev->dev->event = uinput_dev_event;
 	input_set_drvdata(udev->dev, udev);
 
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 42bad18c66c9..496e073b09d7 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -463,6 +463,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = {
 	&sysrq_showstate_blocked_op,	/* w */
 	/* x: May be registered on ppc/powerpc for xmon */
 	/* x: May be registered on sparc64 for global PMU dump */
+	/* x: May be registered on x86_64 for disabling secure boot */
 	NULL,				/* x */
 	/* y: May be registered on sparc64 for global register dump */
 	NULL,				/* y */
@@ -506,7 +507,7 @@ static void __sysrq_put_key_op(int key, struct sysrq_key_op *op_p)
                 sysrq_key_table[i] = op_p;
 }
 
-void __handle_sysrq(int key, bool check_mask)
+void __handle_sysrq(int key, int from)
 {
 	struct sysrq_key_op *op_p;
 	int orig_log_level;
@@ -526,11 +527,15 @@ void __handle_sysrq(int key, bool check_mask)
 
         op_p = __sysrq_get_key_op(key);
         if (op_p) {
+		/* Ban synthetic events from some sysrq functionality */
+		if ((from == SYSRQ_FROM_PROC || from == SYSRQ_FROM_SYNTHETIC) &&
+		    op_p->enable_mask & SYSRQ_DISABLE_USERSPACE)
+			printk("This sysrq operation is disabled from userspace.\n");
 		/*
 		 * Should we check for enabled operations (/proc/sysrq-trigger
 		 * should not) and is the invoked operation enabled?
 		 */
-		if (!check_mask || sysrq_on_mask(op_p->enable_mask)) {
+		if (from == SYSRQ_FROM_KERNEL || sysrq_on_mask(op_p->enable_mask)) {
 			printk("%s\n", op_p->action_msg);
 			console_loglevel = orig_log_level;
 			op_p->handler(key);
@@ -562,7 +567,7 @@ void __handle_sysrq(int key, bool check_mask)
 void handle_sysrq(int key)
 {
 	if (sysrq_on())
-		__handle_sysrq(key, true);
+		__handle_sysrq(key, SYSRQ_FROM_KERNEL);
 }
 EXPORT_SYMBOL(handle_sysrq);
 
@@ -642,7 +647,7 @@ static void sysrq_do_reset(unsigned long _state)
 static void sysrq_handle_reset_request(struct sysrq_state *state)
 {
 	if (state->reset_requested)
-		__handle_sysrq(sysrq_xlate[KEY_B], false);
+		__handle_sysrq(sysrq_xlate[KEY_B], SYSRQ_FROM_KERNEL);
 
 	if (sysrq_reset_downtime_ms)
 		mod_timer(&state->keyreset_timer,
@@ -793,8 +798,10 @@ static bool sysrq_handle_keypress(struct sysrq_state *sysrq,
 
 	default:
 		if (sysrq->active && value && value != 2) {
+			int from = sysrq->handle.dev->flags & INPUTDEV_FLAGS_SYNTHETIC ?
+					SYSRQ_FROM_SYNTHETIC : 0;
 			sysrq->need_reinject = false;
-			__handle_sysrq(sysrq_xlate[code], true);
+			__handle_sysrq(sysrq_xlate[code], from);
 		}
 		break;
 	}
@@ -1089,7 +1096,7 @@ static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf,
 
 		if (get_user(c, buf))
 			return -EFAULT;
-		__handle_sysrq(c, false);
+		__handle_sysrq(c, SYSRQ_FROM_PROC);
 	}
 
 	return count;
diff --git a/include/linux/input.h b/include/linux/input.h
index 82ce323b9986..9e534f228945 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -42,6 +42,7 @@ struct input_value {
  * @phys: physical path to the device in the system hierarchy
  * @uniq: unique identification code for the device (if device has it)
  * @id: id of the device (struct input_id)
+ * @flags: input device flags (SYNTHETIC, etc.)
  * @propbit: bitmap of device properties and quirks
  * @evbit: bitmap of types of events supported by the device (EV_KEY,
  *	EV_REL, etc.)
@@ -124,6 +125,8 @@ struct input_dev {
 	const char *uniq;
 	struct input_id id;
 
+	unsigned int flags;
+
 	unsigned long propbit[BITS_TO_LONGS(INPUT_PROP_CNT)];
 
 	unsigned long evbit[BITS_TO_LONGS(EV_CNT)];
@@ -190,6 +193,8 @@ struct input_dev {
 };
 #define to_input_dev(d) container_of(d, struct input_dev, dev)
 
+#define	INPUTDEV_FLAGS_SYNTHETIC	0x000000001
+
 /*
  * Verify that we are in sync with input_device_id mod_devicetable.h #defines
  */
diff --git a/include/linux/sysrq.h b/include/linux/sysrq.h
index 387fa7d05c98..4b07e30b3279 100644
--- a/include/linux/sysrq.h
+++ b/include/linux/sysrq.h
@@ -28,6 +28,8 @@
 #define SYSRQ_ENABLE_BOOT	0x0080
 #define SYSRQ_ENABLE_RTNICE	0x0100
 
+#define SYSRQ_DISABLE_USERSPACE	0x00010000
+
 struct sysrq_key_op {
 	void (*handler)(int);
 	char *help_msg;
@@ -42,8 +44,12 @@ struct sysrq_key_op {
  * are available -- else NULL's).
  */
 
+#define SYSRQ_FROM_KERNEL	0x0001
+#define SYSRQ_FROM_PROC		0x0002
+#define SYSRQ_FROM_SYNTHETIC	0x0004
+
 void handle_sysrq(int key);
-void __handle_sysrq(int key, bool check_mask);
+void __handle_sysrq(int key, int from);
 int register_sysrq_key(int key, struct sysrq_key_op *op);
 int unregister_sysrq_key(int key, struct sysrq_key_op *op);
 struct sysrq_key_op *__sysrq_get_key_op(int key);
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 379650b984f8..070f29fefdc2 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -1924,7 +1924,7 @@ static int kdb_sr(int argc, const char **argv)
 	if (argc != 1)
 		return KDB_ARGCOUNT;
 	kdb_trap_printk++;
-	__handle_sysrq(*argv[1], false);
+	__handle_sysrq(*argv[1], SYSRQ_FROM_KERNEL);
 	kdb_trap_printk--;
 
 	return 0;
diff --git a/kernel/module.c b/kernel/module.c
index 866417ecc76a..d7ca95c5a349 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -108,9 +108,9 @@ struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
 
 #ifdef CONFIG_MODULE_SIG
 #ifdef CONFIG_MODULE_SIG_FORCE
-static bool sig_enforce = true;
+bool sig_enforce = true;
 #else
-static bool sig_enforce = false;
+bool sig_enforce = false;
 
 static int param_set_bool_enable_only(const char *val,
 				      const struct kernel_param *kp)
-- 
1.9.3