[PATCH v2 2/9] sysctl: Move some boundary constants from sysctl.c to sysctl_vals
From: Luis Chamberlain
Date: Tue Nov 23 2021 - 15:24:44 EST
From: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
sysctl has helpers which let us specify boundary values for a min or
max int value. Since these are used for a boundary check only they don't
change, so move these variables to sysctl_vals to avoid adding duplicate
variables. This will help with our cleanup of kernel/sysctl.c.
Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
[mcgrof: major rebase]
Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
---
fs/proc/proc_sysctl.c | 2 +-
include/linux/sysctl.h | 12 +++++++++---
kernel/sysctl.c | 44 ++++++++++++++++++------------------------
3 files changed, 29 insertions(+), 29 deletions(-)
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index b4950843d90a..6d462644bb00 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -26,7 +26,7 @@ static const struct file_operations proc_sys_dir_file_operations;
static const struct inode_operations proc_sys_dir_operations;
/* shared constants to be used in various sysctls */
-const int sysctl_vals[] = { 0, 1, INT_MAX };
+const int sysctl_vals[] = { -1, 0, 1, 2, 4, 100, 200, 1000, INT_MAX };
EXPORT_SYMBOL(sysctl_vals);
/* Support for permanently empty directories */
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index d3ab7969b6b5..718492057c70 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -38,9 +38,15 @@ struct ctl_table_header;
struct ctl_dir;
/* Keep the same order as in fs/proc/proc_sysctl.c */
-#define SYSCTL_ZERO ((void *)&sysctl_vals[0])
-#define SYSCTL_ONE ((void *)&sysctl_vals[1])
-#define SYSCTL_INT_MAX ((void *)&sysctl_vals[2])
+#define SYSCTL_NEG_ONE ((void *)&sysctl_vals[0])
+#define SYSCTL_ZERO ((void *)&sysctl_vals[1])
+#define SYSCTL_ONE ((void *)&sysctl_vals[2])
+#define SYSCTL_TWO ((void *)&sysctl_vals[3])
+#define SYSCTL_FOUR ((void *)&sysctl_vals[4])
+#define SYSCTL_ONE_HUNDRED ((void *)&sysctl_vals[5])
+#define SYSCTL_TWO_HUNDRED ((void *)&sysctl_vals[6])
+#define SYSCTL_ONE_THOUSAND ((void *)&sysctl_vals[7])
+#define SYSCTL_INT_MAX ((void *)&sysctl_vals[8])
extern const int sysctl_vals[];
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 857c1ccad9e8..3097f0286504 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -113,15 +113,9 @@
static int sixty = 60;
#endif
-static int __maybe_unused neg_one = -1;
-static int __maybe_unused two = 2;
-static int __maybe_unused four = 4;
static unsigned long zero_ul;
static unsigned long one_ul = 1;
static unsigned long long_max = LONG_MAX;
-static int one_hundred = 100;
-static int two_hundred = 200;
-static int one_thousand = 1000;
#ifdef CONFIG_PRINTK
static int ten_thousand = 10000;
#endif
@@ -1962,7 +1956,7 @@ static struct ctl_table kern_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &neg_one,
+ .extra1 = SYSCTL_NEG_ONE,
.extra2 = SYSCTL_ONE,
},
#endif
@@ -2304,7 +2298,7 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax_sysadmin,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
#endif
{
@@ -2564,7 +2558,7 @@ static struct ctl_table kern_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &neg_one,
+ .extra1 = SYSCTL_NEG_ONE,
},
#endif
#ifdef CONFIG_RT_MUTEXES
@@ -2626,7 +2620,7 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = perf_cpu_time_max_percent_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = SYSCTL_ONE_HUNDRED,
},
{
.procname = "perf_event_max_stack",
@@ -2644,7 +2638,7 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = perf_event_max_stack_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_thousand,
+ .extra2 = SYSCTL_ONE_THOUSAND,
},
#endif
{
@@ -2675,7 +2669,7 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = bpf_unpriv_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
{
.procname = "bpf_stats_enabled",
@@ -2729,7 +2723,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = overcommit_policy_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
{
.procname = "panic_on_oom",
@@ -2738,7 +2732,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
{
.procname = "oom_kill_allocating_task",
@@ -2783,7 +2777,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = dirty_background_ratio_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = SYSCTL_ONE_HUNDRED,
},
{
.procname = "dirty_background_bytes",
@@ -2800,7 +2794,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = dirty_ratio_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = SYSCTL_ONE_HUNDRED,
},
{
.procname = "dirty_bytes",
@@ -2840,7 +2834,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two_hundred,
+ .extra2 = SYSCTL_TWO_HUNDRED,
},
#ifdef CONFIG_HUGETLB_PAGE
{
@@ -2897,7 +2891,7 @@ static struct ctl_table vm_table[] = {
.mode = 0200,
.proc_handler = drop_caches_sysctl_handler,
.extra1 = SYSCTL_ONE,
- .extra2 = &four,
+ .extra2 = SYSCTL_FOUR,
},
#ifdef CONFIG_COMPACTION
{
@@ -2914,7 +2908,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = compaction_proactiveness_sysctl_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = SYSCTL_ONE_HUNDRED,
},
{
.procname = "extfrag_threshold",
@@ -2959,7 +2953,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = watermark_scale_factor_sysctl_handler,
.extra1 = SYSCTL_ONE,
- .extra2 = &one_thousand,
+ .extra2 = SYSCTL_ONE_THOUSAND,
},
{
.procname = "percpu_pagelist_high_fraction",
@@ -3038,7 +3032,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = SYSCTL_ONE_HUNDRED,
},
{
.procname = "min_slab_ratio",
@@ -3047,7 +3041,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = sysctl_min_slab_ratio_sysctl_handler,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = SYSCTL_ONE_HUNDRED,
},
#endif
#ifdef CONFIG_SMP
@@ -3337,7 +3331,7 @@ static struct ctl_table fs_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
{
.procname = "protected_regular",
@@ -3346,7 +3340,7 @@ static struct ctl_table fs_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
{
.procname = "suid_dumpable",
@@ -3355,7 +3349,7 @@ static struct ctl_table fs_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax_coredump,
.extra1 = SYSCTL_ZERO,
- .extra2 = &two,
+ .extra2 = SYSCTL_TWO,
},
#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
{
--
2.33.0