hibernate: Disable in a signed modules environment

Orabug: 21539498

There is currently no way to verify the resume image when returning
from hibernate.  This might compromise the signed modules trust model,
so until we can work with signed hibernate images we disable it in
a secure modules environment.

Signed-off-by: Josh Boyer <jwboyer@fedoraproject.com>
Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 2329daae5255374ca8db8619d577ed8e8274fccb..b2579f6e6d98b8f8d3bd4a45915eee8f15b7a718 100644 (file)
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -30,6 +30,8 @@
 #include <linux/genhd.h>
 #include <linux/ktime.h>
 #include <trace/events/power.h>
+#include <linux/security.h>
+#include <linux/efi.h>
 
 #include "power.h"
 
@@ -651,6 +653,10 @@ int hibernate(void)
                return -EPERM;
        }
 
+       if (get_securelevel() > 0) {
+               return -EPERM;
+       }
+
        lock_system_sleep();
        /* The snapshot device should not be opened while we're running */
        if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
@@ -743,7 +749,7 @@ static int software_resume(void)
        /*
         * If the user said "noresume".. bail out early.
         */
-       if (noresume || !hibernation_available())
+       if (noresume || !hibernation_available() || get_securelevel() > 0)
                return 0;
 
        /*
@@ -912,6 +918,11 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
        if (!hibernation_available())
                return sprintf(buf, "[disabled]\n");
 
+       if (efi_enabled(EFI_SECURE_BOOT)) {
+               buf += sprintf(buf, "[%s]\n", "disabled");
+               return buf-start;
+       }
+
        for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
                if (!hibernation_modes[i])
                        continue;
@@ -949,6 +960,9 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
        if (!hibernation_available())
                return -EPERM;
 
+       if (get_securelevel() > 0)
+               return -EPERM;
+
        p = memchr(buf, '\n', n);
        len = p ? p - buf : n;
 

diff --git a/kernel/power/main.c b/kernel/power/main.c
index 86e8157a450f51c1ac592d9c8d2fa4a09e47c21f..a432487e6af8df5570d17d91106ee7c3bb4a0c92 100644 (file)
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -15,6 +15,7 @@
 #include <linux/workqueue.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
+#include <linux/efi.h>
 
 #include "power.h"
 
@@ -300,8 +301,13 @@ static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
                        s += sprintf(s,"%s ", pm_states[i]);
 
 #endif
-       if (hibernation_available())
-               s += sprintf(s, "disk ");
+       if (hibernation_available()) {
+               if (!efi_enabled(EFI_SECURE_BOOT)) {
+                       s += sprintf(s, "disk ");
+               } else {
+                       s += sprintf(s, "\n");
+               }
+       }
        if (s != buf)
                /* convert the last space to a newline */
                *(s-1) = '\n';