sysctl: add some missing input constraint checks
Add boundaries of allowed input ranges for: dirty_expire_centisecs,
drop_caches, overcommit_memory, page-cluster and panic_on_oom.
Signed-off-by: Petr Holasek <pholasek@redhat.com>
Acked-by: Dave Young <hidave.darkstar@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 40245d69..97ab169 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -117,6 +117,7 @@
static int zero;
static int __maybe_unused one = 1;
static int __maybe_unused two = 2;
+static int __maybe_unused three = 3;
static unsigned long one_ul = 1;
static int one_hundred = 100;
#ifdef CONFIG_PRINTK
@@ -971,14 +972,18 @@
.data = &sysctl_overcommit_memory,
.maxlen = sizeof(sysctl_overcommit_memory),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &two,
},
{
.procname = "panic_on_oom",
.data = &sysctl_panic_on_oom,
.maxlen = sizeof(sysctl_panic_on_oom),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &two,
},
{
.procname = "oom_kill_allocating_task",
@@ -1006,7 +1011,8 @@
.data = &page_cluster,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
},
{
.procname = "dirty_background_ratio",
@@ -1054,7 +1060,8 @@
.data = &dirty_expire_interval,
.maxlen = sizeof(dirty_expire_interval),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
},
{
.procname = "nr_pdflush_threads",
@@ -1130,6 +1137,8 @@
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = drop_caches_sysctl_handler,
+ .extra1 = &one,
+ .extra2 = &three,
},
#ifdef CONFIG_COMPACTION
{