ARM: prevent VM_GROWSDOWN mmaps extending below FIRST_USER_ADDRESS

[linux-flexiantxendom0-3.2.10.git] / kernel / ksysfs.c

diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 528dd78..4e316e1 100644 (file)
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -11,11 +11,13 @@
 #include <linux/kobject.h>
 #include <linux/string.h>
 #include <linux/sysfs.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/init.h>
 #include <linux/kexec.h>
 #include <linux/profile.h>
+#include <linux/stat.h>
 #include <linux/sched.h>
+#include <linux/capability.h>
 
 #define KERNEL_ATTR_RO(_name) \
 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
@@ -33,7 +35,7 @@ static ssize_t uevent_seqnum_show(struct kobject *kobj,
 }
 KERNEL_ATTR_RO(uevent_seqnum);
 
-/* uevent helper program, used during early boo */
+/* uevent helper program, used during early boot */
 static ssize_t uevent_helper_show(struct kobject *kobj,
                                  struct kobj_attribute *attr, char *buf)
 {
@@ -100,6 +102,26 @@ static ssize_t kexec_crash_loaded_show(struct kobject *kobj,
 }
 KERNEL_ATTR_RO(kexec_crash_loaded);
 
+static ssize_t kexec_crash_size_show(struct kobject *kobj,
+                                      struct kobj_attribute *attr, char *buf)
+{
+       return sprintf(buf, "%zu\n", crash_get_memory_size());
+}
+static ssize_t kexec_crash_size_store(struct kobject *kobj,
+                                  struct kobj_attribute *attr,
+                                  const char *buf, size_t count)
+{
+       unsigned long cnt;
+       int ret;
+
+       if (strict_strtoul(buf, 0, &cnt))
+               return -EINVAL;
+
+       ret = crash_shrink_memory(cnt);
+       return ret < 0 ? ret : count;
+}
+KERNEL_ATTR_RW(kexec_crash_size);
+
 static ssize_t vmcoreinfo_show(struct kobject *kobj,
                               struct kobj_attribute *attr, char *buf)
 {
@@ -111,6 +133,14 @@ KERNEL_ATTR_RO(vmcoreinfo);
 
 #endif /* CONFIG_KEXEC */
 
+/* whether file capabilities are enabled */
+static ssize_t fscaps_show(struct kobject *kobj,
+                                 struct kobj_attribute *attr, char *buf)
+{
+       return sprintf(buf, "%d\n", file_caps_enabled);
+}
+KERNEL_ATTR_RO(fscaps);
+
 /*
  * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
  */
@@ -118,7 +148,8 @@ extern const void __start_notes __attribute__((weak));
 extern const void __stop_notes __attribute__((weak));
 #define        notes_size (&__stop_notes - &__start_notes)
 
-static ssize_t notes_read(struct kobject *kobj, struct bin_attribute *bin_attr,
+static ssize_t notes_read(struct file *filp, struct kobject *kobj,
+                         struct bin_attribute *bin_attr,
                          char *buf, loff_t off, size_t count)
 {
        memcpy(buf, &__start_notes + off, count);
@@ -137,6 +168,7 @@ struct kobject *kernel_kobj;
 EXPORT_SYMBOL_GPL(kernel_kobj);
 
 static struct attribute * kernel_attrs[] = {
+       &fscaps_attr.attr,
 #if defined(CONFIG_HOTPLUG)
        &uevent_seqnum_attr.attr,
        &uevent_helper_attr.attr,
@@ -147,6 +179,7 @@ static struct attribute * kernel_attrs[] = {
 #ifdef CONFIG_KEXEC
        &kexec_loaded_attr.attr,
        &kexec_crash_loaded_attr.attr,
+       &kexec_crash_size_attr.attr,
        &vmcoreinfo_attr.attr,
 #endif
        NULL
@@ -176,16 +209,8 @@ static int __init ksysfs_init(void)
                        goto group_exit;
        }
 
-       /* create the /sys/kernel/uids/ directory */
-       error = uids_sysfs_init();
-       if (error)
-               goto notes_exit;
-
        return 0;
 
-notes_exit:
-       if (notes_size > 0)
-               sysfs_remove_bin_file(kernel_kobj, &notes_attr);
 group_exit:
        sysfs_remove_group(kernel_kobj, &kernel_attr_group);
 kset_exit: