futex: Do not leak robust list to unprivileged process

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

diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c
index 3b34b35..63da38c 100644 (file)
--- a/kernel/utsname_sysctl.c
+++ b/kernel/utsname_sysctl.c
@@ -9,10 +9,11 @@
  *  License.
  */
 
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/uts.h>
 #include <linux/utsname.h>
 #include <linux/sysctl.h>
+#include <linux/wait.h>
 
 static void *get_uts(ctl_table *table, int write)
 {
@@ -37,98 +38,76 @@ static void put_uts(ctl_table *table, int write, void *which)
                up_write(&uts_sem);
 }
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_SYSCTL
 /*
  *     Special case of dostring for the UTS structure. This has locks
  *     to observe. Should this be in kernel/sys.c ????
  */
-static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
+static int proc_do_uts_string(ctl_table *table, int write,
                  void __user *buffer, size_t *lenp, loff_t *ppos)
 {
        struct ctl_table uts_table;
        int r;
        memcpy(&uts_table, table, sizeof(uts_table));
        uts_table.data = get_uts(table, write);
-       r = proc_dostring(&uts_table,write,filp,buffer,lenp, ppos);
+       r = proc_dostring(&uts_table,write,buffer,lenp, ppos);
        put_uts(table, write, uts_table.data);
-       return r;
-}
-#else
-#define proc_do_uts_string NULL
-#endif
 
+       if (write)
+               proc_sys_poll_notify(table->poll);
 
-#ifdef CONFIG_SYSCTL_SYSCALL
-/* The generic string strategy routine: */
-static int sysctl_uts_string(ctl_table *table,
-                 void __user *oldval, size_t __user *oldlenp,
-                 void __user *newval, size_t newlen)
-{
-       struct ctl_table uts_table;
-       int r, write;
-       write = newval && newlen;
-       memcpy(&uts_table, table, sizeof(uts_table));
-       uts_table.data = get_uts(table, write);
-       r = sysctl_string(&uts_table, oldval, oldlenp, newval, newlen);
-       put_uts(table, write, uts_table.data);
        return r;
 }
 #else
-#define sysctl_uts_string NULL
+#define proc_do_uts_string NULL
 #endif
 
+static DEFINE_CTL_TABLE_POLL(hostname_poll);
+static DEFINE_CTL_TABLE_POLL(domainname_poll);
+
 static struct ctl_table uts_kern_table[] = {
        {
-               .ctl_name       = KERN_OSTYPE,
                .procname       = "ostype",
                .data           = init_uts_ns.name.sysname,
                .maxlen         = sizeof(init_uts_ns.name.sysname),
                .mode           = 0444,
                .proc_handler   = proc_do_uts_string,
-               .strategy       = sysctl_uts_string,
        },
        {
-               .ctl_name       = KERN_OSRELEASE,
                .procname       = "osrelease",
                .data           = init_uts_ns.name.release,
                .maxlen         = sizeof(init_uts_ns.name.release),
                .mode           = 0444,
                .proc_handler   = proc_do_uts_string,
-               .strategy       = sysctl_uts_string,
        },
        {
-               .ctl_name       = KERN_VERSION,
                .procname       = "version",
                .data           = init_uts_ns.name.version,
                .maxlen         = sizeof(init_uts_ns.name.version),
                .mode           = 0444,
                .proc_handler   = proc_do_uts_string,
-               .strategy       = sysctl_uts_string,
        },
        {
-               .ctl_name       = KERN_NODENAME,
                .procname       = "hostname",
                .data           = init_uts_ns.name.nodename,
                .maxlen         = sizeof(init_uts_ns.name.nodename),
                .mode           = 0644,
                .proc_handler   = proc_do_uts_string,
-               .strategy       = sysctl_uts_string,
+               .poll           = &hostname_poll,
        },
        {
-               .ctl_name       = KERN_DOMAINNAME,
                .procname       = "domainname",
                .data           = init_uts_ns.name.domainname,
                .maxlen         = sizeof(init_uts_ns.name.domainname),
                .mode           = 0644,
                .proc_handler   = proc_do_uts_string,
-               .strategy       = sysctl_uts_string,
+               .poll           = &domainname_poll,
        },
        {}
 };
 
 static struct ctl_table uts_root_table[] = {
        {
-               .ctl_name       = CTL_KERN,
                .procname       = "kernel",
                .mode           = 0555,
                .child          = uts_kern_table,
@@ -136,6 +115,19 @@ static struct ctl_table uts_root_table[] = {
        {}
 };
 
+#ifdef CONFIG_PROC_SYSCTL
+/*
+ * Notify userspace about a change in a certain entry of uts_kern_table,
+ * identified by the parameter proc.
+ */
+void uts_proc_notify(enum uts_proc proc)
+{
+       struct ctl_table *table = &uts_kern_table[proc];
+
+       proc_sys_poll_notify(table->poll);
+}
+#endif
+
 static int __init utsname_sysctl_init(void)
 {
        register_sysctl_table(uts_root_table);