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authorEric W. Biederman <ebiederm@xmission.com>2009-04-02 23:44:59 -0700
committerEric W. Biederman <ebiederm@xmission.com>2009-11-06 03:20:07 -0800
commitafa588b2651a03da4bc601a17a244b1cd97264f2 (patch)
treecb7a03753f282b4e459305fec307caf0837e756b /kernel/sysctl_binary.c
parentb419148e567728f6af0c3b01965c1cc141e3e13a (diff)
downloadlinux-2.6.34-ux500-afa588b2651a03da4bc601a17a244b1cd97264f2.tar.gz
sysctl: Separate the binary sysctl logic into it's own file.
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>
Diffstat (limited to 'kernel/sysctl_binary.c')
-rw-r--r--kernel/sysctl_binary.c185
1 files changed, 185 insertions, 0 deletions
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
new file mode 100644
index 00000000000..eceeed20ca8
--- /dev/null
+++ b/kernel/sysctl_binary.c
@@ -0,0 +1,185 @@
+#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>
+#include <linux/smp_lock.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;
+}