sysctl: fix write access to dmesg_restrict/kptr_restrict

[linux-flexiantxendom0.git] / kernel / sysctl.c

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 4fc9244..ea7ec7f 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -57,6 +57,7 @@
 #include <linux/pipe_fs_i.h>
 #include <linux/oom.h>
 #include <linux/kmod.h>
+#include <linux/capability.h>
 
 #include <asm/uaccess.h>
 #include <asm/processor.h>
@@ -134,6 +135,7 @@ static int minolduid;
 static int min_percpu_pagelist_fract = 8;
 
 static int ngroups_max = NGROUPS_MAX;
+static const int cap_last_cap = CAP_LAST_CAP;
 
 #ifdef CONFIG_INOTIFY_USER
 #include <linux/inotify.h>
@@ -151,14 +153,6 @@ extern int pwrsw_enabled;
 extern int unaligned_enabled;
 #endif
 
-#ifdef CONFIG_S390
-#ifdef CONFIG_MATHEMU
-extern int sysctl_ieee_emulation_warnings;
-#endif
-extern int sysctl_userprocess_debug;
-extern int spin_retry;
-#endif
-
 #ifdef CONFIG_IA64
 extern int no_unaligned_warning;
 extern int unaligned_dump_stack;
@@ -172,7 +166,7 @@ static int proc_taint(struct ctl_table *table, int write,
 #endif
 
 #ifdef CONFIG_PRINTK
-static int proc_dmesg_restrict(struct ctl_table *table, int write,
+static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
                                void __user *buffer, size_t *lenp, loff_t *ppos);
 #endif
 
@@ -379,6 +373,16 @@ static struct ctl_table kern_table[] = {
                .extra2         = &one,
        },
 #endif
+#ifdef CONFIG_CFS_BANDWIDTH
+       {
+               .procname       = "sched_cfs_bandwidth_slice_us",
+               .data           = &sysctl_sched_cfs_bandwidth_slice,
+               .maxlen         = sizeof(unsigned int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec_minmax,
+               .extra1         = &one,
+       },
+#endif
 #ifdef CONFIG_PROVE_LOCKING
        {
                .procname       = "prove_locking",
@@ -709,7 +713,7 @@ static struct ctl_table kern_table[] = {
                .data           = &dmesg_restrict,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = proc_dointvec_minmax,
+               .proc_handler   = proc_dointvec_minmax_sysadmin,
                .extra1         = &zero,
                .extra2         = &one,
        },
@@ -718,7 +722,7 @@ static struct ctl_table kern_table[] = {
                .data           = &kptr_restrict,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = proc_dmesg_restrict,
+               .proc_handler   = proc_dointvec_minmax_sysadmin,
                .extra1         = &zero,
                .extra2         = &two,
        },
@@ -730,6 +734,13 @@ static struct ctl_table kern_table[] = {
                .mode           = 0444,
                .proc_handler   = proc_dointvec,
        },
+       {
+               .procname       = "cap_last_cap",
+               .data           = (void *)&cap_last_cap,
+               .maxlen         = sizeof(int),
+               .mode           = 0444,
+               .proc_handler   = proc_dointvec,
+       },
 #if defined(CONFIG_LOCKUP_DETECTOR)
        {
                .procname       = "watchdog",
@@ -938,6 +949,12 @@ static struct ctl_table kern_table[] = {
        },
 #endif
 #ifdef CONFIG_PERF_EVENTS
+       /*
+        * User-space scripts rely on the existence of this file
+        * as a feature check for perf_events being enabled.
+        *
+        * So it's an ABI, do not remove!
+        */
        {
                .procname       = "perf_event_paranoid",
                .data           = &sysctl_perf_event_paranoid,
@@ -1584,16 +1601,11 @@ void sysctl_head_get(struct ctl_table_header *head)
        spin_unlock(&sysctl_lock);
 }
 
-static void free_head(struct rcu_head *rcu)
-{
-       kfree(container_of(rcu, struct ctl_table_header, rcu));
-}
-
 void sysctl_head_put(struct ctl_table_header *head)
 {
        spin_lock(&sysctl_lock);
        if (!--head->count)
-               call_rcu(&head->rcu, free_head);
+               kfree_rcu(head, rcu);
        spin_unlock(&sysctl_lock);
 }
 
@@ -1965,10 +1977,10 @@ void unregister_sysctl_table(struct ctl_table_header * header)
        start_unregistering(header);
        if (!--header->parent->count) {
                WARN_ON(1);
-               call_rcu(&header->parent->rcu, free_head);
+               kfree_rcu(header->parent, rcu);
        }
        if (!--header->count)
-               call_rcu(&header->rcu, free_head);
+               kfree_rcu(header, rcu);
        spin_unlock(&sysctl_lock);
 }
 
@@ -2410,7 +2422,7 @@ static int proc_taint(struct ctl_table *table, int write,
 }
 
 #ifdef CONFIG_PRINTK
-static int proc_dmesg_restrict(struct ctl_table *table, int write,
+static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
                                void __user *buffer, size_t *lenp, loff_t *ppos)
 {
        if (write && !capable(CAP_SYS_ADMIN))