From: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> - unquoted This is just a simple cleanup to keep kernel/sysctl.c from getting to crowded with special cases, and by keeping all of the utsname logic to together it makes the code a little more readable. Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> --- kernel/Makefile | 1 + kernel/sysctl.c | 115 ------------------------------------- kernel/utsname_sysctl.c | 146 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 147 insertions(+), 115 deletions(-) diff --git a/kernel/Makefile b/kernel/Makefile index 14f4d45..d286c44 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_SECCOMP) += seccomp.o obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o obj-$(CONFIG_RELAY) += relay.o obj-$(CONFIG_UTS_NS) += utsname.o +obj-$(CONFIG_SYSCTL) += utsname_sysctl.o obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 7420761..a8c0a03 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -135,13 +135,6 @@ static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t, ctl_table *); #endif -static int proc_do_uts_string(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos); - -static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen, - void __user *oldval, size_t __user *oldlenp, - void __user *newval, size_t newlen); - #ifdef CONFIG_SYSVIPC static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, @@ -174,27 +167,6 @@ extern ctl_table inotify_table[]; int sysctl_legacy_va_layout; #endif -static void *get_uts(ctl_table *table, int write) -{ - char *which = table->data; -#ifdef CONFIG_UTS_NS - struct uts_namespace *uts_ns = current->nsproxy->uts_ns; - which = (which - (char *)&init_uts_ns) + (char *)uts_ns; -#endif - if (!write) - down_read(&uts_sem); - else - down_write(&uts_sem); - return which; -} - -static void put_uts(ctl_table *table, int write, void *which) -{ - if (!write) - up_read(&uts_sem); - else - up_write(&uts_sem); -} #ifdef CONFIG_SYSVIPC static void *get_ipc(ctl_table *table, int write) @@ -275,51 +247,6 @@ static ctl_table root_table[] = { static ctl_table 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, - }, - { - .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, - }, - { .ctl_name = KERN_PANIC, .procname = "panic", .data = &panic_timeout, @@ -1746,21 +1673,6 @@ int proc_dostring(ctl_table *table, int write, struct file *filp, buffer, lenp, ppos); } -/* - * 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, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - int r; - void *which; - which = get_uts(table, write); - r = _proc_do_string(which, table->maxlen,write,filp,buffer,lenp, ppos); - put_uts(table, write, which); - return r; -} static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp, int *valp, @@ -2379,12 +2291,6 @@ int proc_dostring(ctl_table *table, int write, struct file *filp, return -ENOSYS; } -static int proc_do_uts_string(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - #ifdef CONFIG_SYSVIPC static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) @@ -2602,21 +2508,6 @@ int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, } -/* The generic string strategy routine: */ -static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen, - 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, name, nlen, - oldval, oldlenp, newval, newlen); - put_uts(table, write, uts_table.data); - return r; -} #ifdef CONFIG_SYSVIPC /* The generic sysctl ipc data routine. */ @@ -2723,12 +2614,6 @@ int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, return -ENOSYS; } -static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen, - void __user *oldval, size_t __user *oldlenp, - void __user *newval, size_t newlen) -{ - return -ENOSYS; -} static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen) diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c new file mode 100644 index 0000000..324aa13 --- /dev/null +++ b/kernel/utsname_sysctl.c @@ -0,0 +1,146 @@ +/* + * Copyright (C) 2007 + * + * Author: Eric Biederman <ebiederm@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include <linux/module.h> +#include <linux/uts.h> +#include <linux/utsname.h> +#include <linux/version.h> +#include <linux/sysctl.h> + +static void *get_uts(ctl_table *table, int write) +{ + char *which = table->data; +#ifdef CONFIG_UTS_NS + struct uts_namespace *uts_ns = current->nsproxy->uts_ns; + which = (which - (char *)&init_uts_ns) + (char *)uts_ns; +#endif + if (!write) + down_read(&uts_sem); + else + down_write(&uts_sem); + return which; +} + +static void put_uts(ctl_table *table, int write, void *which) +{ + if (!write) + up_read(&uts_sem); + else + up_write(&uts_sem); +} + +#ifdef CONFIG_PROC_FS +/* + * 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, + 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); + put_uts(table, write, uts_table.data); + return r; +} +#else +#define proc_do_uts_string NULL +#endif + + +#ifdef CONFIG_SYSCTL_SYSCALL +/* The generic string strategy routine: */ +static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen, + 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, name, nlen, + oldval, oldlenp, newval, newlen); + put_uts(table, write, uts_table.data); + return r; +} +#else +#define sysctl_uts_string NULL +#endif + +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, + }, + { + .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, + }, + {} +}; + +static struct ctl_table uts_root_table[] = { + { + .ctl_name = CTL_KERN, + .procname = "kernel", + .mode = 0555, + .child = uts_kern_table, + }, + {} +}; + +static int __init utsname_sysctl_init(void) +{ + register_sysctl_table(uts_root_table, 0); + return 0; +} + +__initcall(utsname_sysctl_init); -- 1.4.4.1.g278f