[PATCH 01/11] sysctl: Separate the binary sysctl logic into it's own file.

Eric W. Biederman
2009-11-06T00:42:04Z

From: Eric W. Biederman <ebiederm@xmission.com>

In preparation for more invasive cleanups separate the core
binary sysctl logic into it's own file.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
kernel/Makefile | 2 +-
kernel/sysctl.c | 164 ------------------------------------------
kernel/sysctl_binary.c | 184 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 185 insertions(+), 165 deletions(-)
create mode 100644 kernel/sysctl_binary.c

diff --git a/kernel/Makefile b/kernel/Makefile
index b8d4cd8..986a5c1 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -4,7 +4,7 @@

obj-y = sched.o fork.o exec_domain.o panic.o printk.o \
cpu.o exit.o itimer.o time.o softirq.o resource.o \
- sysctl.o capability.o ptrace.o timer.o user.o \
+ sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \
signal.o sys.o kmod.o workqueue.o pid.o \
rcupdate.o extable.o params.o posix-timers.o \
kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 0d949c5..34c8dbc 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -60,7 +60,6 @@
#include <asm/io.h>
#endif

-static int deprecated_sysctl_warning(struct __sysctl_args *args);

#if defined(CONFIG_SYSCTL)

@@ -1766,122 +1765,6 @@ void register_sysctl_root(struct ctl_table_root *root)
spin_unlock(&sysctl_lock);
}

-#ifdef CONFIG_SYSCTL_SYSCALL
-/* Perform the actual read/write of a sysctl table entry. */
-static int do_sysctl_strategy(struct ctl_table_root *root,
- struct ctl_table *table,
- void __user *oldval, size_t __user *oldlenp,
- void __user *newval, size_t newlen)
-{
- int op = 0, rc;
-
- if (oldval)
- op |= MAY_READ;
- if (newval)
- op |= MAY_WRITE;
- if (sysctl_perm(root, table, op))
- return -EPERM;
-
- if (table->strategy) {
- rc = table->strategy(table, oldval, oldlenp, newval, newlen);
- if (rc < 0)
- return rc;
- if (rc > 0)
- return 0;
- }
-
- /* If there is no strategy routine, or if the strategy returns
- * zero, proceed with automatic r/w */
- if (table->data && table->maxlen) {
- rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
- if (rc < 0)
- return rc;
- }
- return 0;
-}
-
-static int parse_table(int __user *name, int nlen,
- void __user *oldval, size_t __user *oldlenp,
- void __user *newval, size_t newlen,
- struct ctl_table_root *root,
- struct ctl_table *table)
-{
- int n;
-repeat:
- if (!nlen)
- return -ENOTDIR;
- if (get_user(n, name))
- return -EFAULT;
- for ( ; table->ctl_name || table->procname; table++) {
- if (!table->ctl_name)
- continue;
- if (n == table->ctl_name) {
- int error;
- if (table->child) {
- if (sysctl_perm(root, table, MAY_EXEC))
- return -EPERM;
- name++;
- nlen--;
- table = table->child;
- goto repeat;
- }
- error = do_sysctl_strategy(root, table,
- oldval, oldlenp,
- newval, newlen);
- return error;
- }
- }
- return -ENOTDIR;
-}
-
-int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
- void __user *newval, size_t newlen)
-{
- struct ctl_table_header *head;
- int error = -ENOTDIR;
-
- if (nlen <= 0 || nlen >= CTL_MAXNAME)
- return -ENOTDIR;
- if (oldval) {
- int old_len;
- if (!oldlenp || get_user(old_len, oldlenp))
- return -EFAULT;
- }
-
- for (head = sysctl_head_next(NULL); head;
- head = sysctl_head_next(head)) {
- error = parse_table(name, nlen, oldval, oldlenp,
- newval, newlen,
- head->root, head->ctl_table);
- if (error != -ENOTDIR) {
- sysctl_head_finish(head);
- break;
- }
- }
- return error;
-}
-
-SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
-{
- struct __sysctl_args tmp;
- int error;
-
- if (copy_from_user(&tmp, args, sizeof(tmp)))
- return -EFAULT;
-
- error = deprecated_sysctl_warning(&tmp);
- if (error)
- goto out;
-
- lock_kernel();
- error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
- tmp.newval, tmp.newlen);
- unlock_kernel();
-out:
- return error;
-}
-#endif /* CONFIG_SYSCTL_SYSCALL */
-
/*
* sysctl_perm does NOT grant the superuser all rights automatically, because
* some sysctl variables are readonly even to root.
@@ -3148,23 +3031,6 @@ int sysctl_ms_jiffies(struct ctl_table *table,
#else /* CONFIG_SYSCTL_SYSCALL */

-SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
-{
- struct __sysctl_args tmp;
- int error;
-
- if (copy_from_user(&tmp, args, sizeof(tmp)))
- return -EFAULT;
-
- error = deprecated_sysctl_warning(&tmp);
-
- /* If no error reading the parameters then just -ENOSYS ... */
- if (!error)
- error = -ENOSYS;
-
- return error;
-}
-
int sysctl_data(struct ctl_table *table,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
@@ -3202,36 +3068,6 @@ int sysctl_ms_jiffies(struct ctl_table *table,

#endif /* CONFIG_SYSCTL_SYSCALL */

-static int deprecated_sysctl_warning(struct __sysctl_args *args)
-{
- static int msg_count;
- int name[CTL_MAXNAME];
- int i;
-
- /* Check args->nlen. */
- if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
- return -ENOTDIR;
-
- /* Read in the sysctl name for better debug message logging */
- for (i = 0; i < args->nlen; i++)
- if (get_user(name[i], args->name + i))
- return -EFAULT;
-
- /* Ignore accesses to kernel.version */
- if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
- return 0;
-
- if (msg_count < 5) {
- msg_count++;
- printk(KERN_INFO
- "warning: process `%s' used the deprecated sysctl "
- "system call with ", current->comm);
- for (i = 0; i < args->nlen; i++)
- printk("%d.", name[i]);
- printk("\n");
- }
- return 0;
-}

/*
* No sense putting this after each symbol definition, twice,
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
new file mode 100644
index 0000000..2431653
--- /dev/null
+++ b/kernel/sysctl_binary.c
@@ -0,0 +1,184 @@
+#include <linux/stat.h>
+#include <linux/sysctl.h>
+#include "../fs/xfs/linux-2.6/xfs_sysctl.h"
+#include <linux/sunrpc/debug.h>
+#include <linux/string.h>
+#include <net/ip_vs.h>
+#include <linux/syscalls.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/fs.h>
+#include <linux/nsproxy.h>
+#include <linux/pid_namespace.h>
+#include <linux/file.h>
+#include <linux/ctype.h>
+
+static int deprecated_sysctl_warning(struct __sysctl_args *args);
+
+#ifdef CONFIG_SYSCTL_SYSCALL
+
+/* Perform the actual read/write of a sysctl table entry. */
+static int do_sysctl_strategy(struct ctl_table_root *root,
+ struct ctl_table *table,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ int op = 0, rc;
+
+ if (oldval)
+ op |= MAY_READ;
+ if (newval)
+ op |= MAY_WRITE;
+ if (sysctl_perm(root, table, op))
+ return -EPERM;
+
+ if (table->strategy) {
+ rc = table->strategy(table, oldval, oldlenp, newval, newlen);
+ if (rc < 0)
+ return rc;
+ if (rc > 0)
+ return 0;
+ }
+
+ /* If there is no strategy routine, or if the strategy returns
+ * zero, proceed with automatic r/w */
+ if (table->data && table->maxlen) {
+ rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
+ if (rc < 0)
+ return rc;
+ }
+ return 0;
+}
+
+static int parse_table(int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen,
+ struct ctl_table_root *root,
+ struct ctl_table *table)
+{
+ int n;
+repeat:
+ if (!nlen)
+ return -ENOTDIR;
+ if (get_user(n, name))
+ return -EFAULT;
+ for ( ; table->ctl_name || table->procname; table++) {
+ if (!table->ctl_name)
+ continue;
+ if (n == table->ctl_name) {
+ int error;
+ if (table->child) {
+ if (sysctl_perm(root, table, MAY_EXEC))
+ return -EPERM;
+ name++;
+ nlen--;
+ table = table->child;
+ goto repeat;
+ }
+ error = do_sysctl_strategy(root, table,
+ oldval, oldlenp,
+ newval, newlen);
+ return error;
+ }
+ }
+ return -ENOTDIR;
+}
+
+int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ struct ctl_table_header *head;
+ int error = -ENOTDIR;
+
+ if (nlen <= 0 || nlen >= CTL_MAXNAME)
+ return -ENOTDIR;
+ if (oldval) {
+ int old_len;
+ if (!oldlenp || get_user(old_len, oldlenp))
+ return -EFAULT;
+ }
+
+ for (head = sysctl_head_next(NULL); head;
+ head = sysctl_head_next(head)) {
+ error = parse_table(name, nlen, oldval, oldlenp,
+ newval, newlen,
+ head->root, head->ctl_table);
+ if (error != -ENOTDIR) {
+ sysctl_head_finish(head);
+ break;
+ }
+ }
+ return error;
+}
+
+SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
+{
+ struct __sysctl_args tmp;
+ int error;
+
+ if (copy_from_user(&tmp, args, sizeof(tmp)))
+ return -EFAULT;
+
+ error = deprecated_sysctl_warning(&tmp);
+ if (error)
+ goto out;
+
+ lock_kernel();
+ error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
+ tmp.newval, tmp.newlen);
+ unlock_kernel();
+out:
+ return error;
+}
+
+#else /* CONFIG_SYSCTL_SYSCALL */
+
+SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
+{
+ struct __sysctl_args tmp;
+ int error;
+
+ if (copy_from_user(&tmp, args, sizeof(tmp)))
+ return -EFAULT;
+
+ error = deprecated_sysctl_warning(&tmp);
+
+ /* If no error reading the parameters then just -ENOSYS ... */
+ if (!error)
+ error = -ENOSYS;
+
+ return error;
+}
+
+#endif /* CONFIG_SYSCTL_SYSCALL */
+
+static int deprecated_sysctl_warning(struct __sysctl_args *args)
+{
+ static int msg_count;
+ int name[CTL_MAXNAME];
+ int i;
+
+ /* Check args->nlen. */
+ if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
+ return -ENOTDIR;
+
+ /* Read in the sysctl name for better debug message logging */
+ for (i = 0; i < args->nlen; i++)
+ if (get_user(name[i], args->name + i))
+ return -EFAULT;
+
+ /* Ignore accesses to kernel.version */
+ if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
+ return 0;
+
+ if (msg_count < 5) {
+ msg_count++;
+ printk(KERN_INFO
+ "warning: process `%s' used the deprecated sysctl "
+ "system call with ", current->comm);
+ for (i = 0; i < args->nlen; i++)
+ printk("%d.", name[i]);
+ printk("\n");
+ }
+ return 0;
+}
--
1.6.5.2.143.g8cc62