From: Tim Hockin <thockin@sun.com>
Attached is a simple patch to expose NGROUPS_MAX via sysctl. Nothing
fancy, just a read-only variable. glibc can use this to sysconf() the
value properly, so apps will stop relying on NGROUPS_MAX as a real
constant.
---
include/linux/sysctl.h | 1 +
kernel/sysctl.c | 11 +++++++++++
2 files changed, 12 insertions(+)
diff -puN include/linux/sysctl.h~NGROUPS_MAX-sysctl include/linux/sysctl.h
--- 25/include/linux/sysctl.h~NGROUPS_MAX-sysctl 2004-02-19 23:26:29.000000000 -0800
+++ 25-akpm/include/linux/sysctl.h 2004-02-19 23:27:18.000000000 -0800
@@ -130,6 +130,7 @@ enum
KERN_PRINTK_RATELIMIT=60, /* int: tune printk ratelimiting */
KERN_PRINTK_RATELIMIT_BURST=61, /* int: tune printk ratelimiting */
KERN_PTY=62, /* dir: pty driver */
+ KERN_NGROUPS_MAX=62, /* int: NGROUPS_MAX */
};
diff -puN kernel/sysctl.c~NGROUPS_MAX-sysctl kernel/sysctl.c
--- 25/kernel/sysctl.c~NGROUPS_MAX-sysctl 2004-02-19 23:26:29.000000000 -0800
+++ 25-akpm/kernel/sysctl.c 2004-02-19 23:26:29.000000000 -0800
@@ -38,6 +38,7 @@
#include <linux/security.h>
#include <linux/initrd.h>
#include <linux/times.h>
+#include <linux/limits.h>
#include <asm/uaccess.h>
#ifdef CONFIG_ROOT_NFS
@@ -68,6 +69,8 @@ extern int printk_ratelimit_burst;
static int maxolduid = 65535;
static int minolduid;
+static int ngroups_max = NGROUPS_MAX;
+
#ifdef CONFIG_KMOD
extern char modprobe_path[];
#endif
@@ -604,6 +607,14 @@ static ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
+ {
+ .ctl_name = KERN_NGROUPS_MAX,
+ .procname = "ngroups_max",
+ .data = &ngroups_max,
+ .maxlen = sizeof (int),
+ .mode = 0444,
+ .proc_handler = &proc_dointvec,
+ },
{ .ctl_name = 0 }
};
_