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 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * sysctl.c: General linux system control interface
  *
  * Begun 24 March 1995, Stephen Tweedie
  * Added /proc support, Dec 1995
  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
  * Dynamic registration fixes, Stephen Tweedie.
  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  *  Horn.
  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  *  Wendling.
  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  */
 
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/slab.h>
 #include <linux/sysctl.h>
 #include <linux/bitmap.h>
 #include <linux/signal.h>
 #include <linux/panic.h>
 #include <linux/printk.h>
 #include <linux/proc_fs.h>
 #include <linux/security.h>
 #include <linux/ctype.h>
 #include <linux/kmemleak.h>
 #include <linux/filter.h>
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/kobject.h>
 #include <linux/net.h>
 #include <linux/sysrq.h>
 #include <linux/highuid.h>
 #include <linux/writeback.h>
 #include <linux/ratelimit.h>
 #include <linux/compaction.h>
 #include <linux/hugetlb.h>
 #include <linux/initrd.h>
 #include <linux/key.h>
 #include <linux/times.h>
 #include <linux/limits.h>
 #include <linux/dcache.h>
 #include <linux/syscalls.h>
 #include <linux/vmstat.h>
 #include <linux/nfs_fs.h>
 #include <linux/acpi.h>
 #include <linux/reboot.h>
 #include <linux/ftrace.h>
 #include <linux/perf_event.h>
 #include <linux/oom.h>
 #include <linux/kmod.h>
 #include <linux/capability.h>
 #include <linux/binfmts.h>
 #include <linux/sched/sysctl.h>
 #include <linux/mount.h>
 #include <linux/userfaultfd_k.h>
 #include <linux/pid.h>
 
 #include "../lib/kstrtox.h"
 
 #include <linux/uaccess.h>
 #include <asm/processor.h>
 
 #ifdef CONFIG_X86
 #include <asm/nmi.h>
 #include <asm/stacktrace.h>
 #include <asm/io.h>
 #endif
 #ifdef CONFIG_SPARC
 #include <asm/setup.h>
 #endif
 #ifdef CONFIG_RT_MUTEXES
 #include <linux/rtmutex.h>
 #endif
 
 #if defined(CONFIG_SYSCTL)
 
 /* Constants used for minimum and  maximum */
 
 #ifdef CONFIG_PERF_EVENTS
 static const int six_hundred_forty_kb = 640 * 1024;
 #endif
 
 
 static const int ngroups_max = NGROUPS_MAX;
 static const int cap_last_cap = CAP_LAST_CAP;
 
 #ifdef CONFIG_PROC_SYSCTL
 
 /**
  * enum sysctl_writes_mode - supported sysctl write modes
  *
  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
  *  to be written, and multiple writes on the same sysctl file descriptor
  *  will rewrite the sysctl value, regardless of file position. No warning
  *  is issued when the initial position is not 0.
  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
  *  not 0.
  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
  *  file position 0 and the value must be fully contained in the buffer
  *  sent to the write syscall. If dealing with strings respect the file
  *  position, but restrict this to the max length of the buffer, anything
  *  passed the max length will be ignored. Multiple writes will append
  *  to the buffer.
  *
  * These write modes control how current file position affects the behavior of
  * updating sysctl values through the proc interface on each write.
  */
 enum sysctl_writes_mode {
     SYSCTL_WRITES_LEGACY        = -1,
     SYSCTL_WRITES_WARN      = 0,
     SYSCTL_WRITES_STRICT        = 1,
 };
 
 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
 #endif /* CONFIG_PROC_SYSCTL */
 
 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
     defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
 int sysctl_legacy_va_layout;
 #endif
 
 #ifdef CONFIG_COMPACTION
 /* min_extfrag_threshold is SYSCTL_ZERO */;
 static const int max_extfrag_threshold = 1000;
 #endif
 
 #endif /* CONFIG_SYSCTL */
 
 /*
  * /proc/sys support
  */
 
 #ifdef CONFIG_PROC_SYSCTL
 
 static int _proc_do_string(char *data, int maxlen, int write,
         char *buffer, size_t *lenp, loff_t *ppos)
 {
     size_t len;
     char c, *p;
 
     if (!data || !maxlen || !*lenp) {
         *lenp = 0;
         return 0;
     }
 
     if (write) {
         if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
             /* Only continue writes not past the end of buffer. */
             len = strlen(data);
             if (len > maxlen - 1)
                 len = maxlen - 1;
 
             if (*ppos > len)
                 return 0;
             len = *ppos;
         } else {
             /* Start writing from beginning of buffer. */
             len = 0;
         }
 
         *ppos += *lenp;
         p = buffer;
         while ((p - buffer) < *lenp && len < maxlen - 1) {
             c = *(p++);
             if (c == 0 || c == '\n')
                 break;
             data[len++] = c;
         }
         data[len] = 0;
     } else {
         len = strlen(data);
         if (len > maxlen)
             len = maxlen;
 
         if (*ppos > len) {
             *lenp = 0;
             return 0;
         }
 
         data += *ppos;
         len  -= *ppos;
 
         if (len > *lenp)
             len = *lenp;
         if (len)
             memcpy(buffer, data, len);
         if (len < *lenp) {
             buffer[len] = '\n';
             len++;
         }
         *lenp = len;
         *ppos += len;
     }
     return 0;
 }
 
 static void warn_sysctl_write(struct ctl_table *table)
 {
     pr_warn_once("%s wrote to %s when file position was not 0!\n"
         "This will not be supported in the future. To silence this\n"
         "warning, set kernel.sysctl_writes_strict = -1\n",
         current->comm, table->procname);
 }
 
 /**
  * proc_first_pos_non_zero_ignore - check if first position is allowed
  * @ppos: file position
  * @table: the sysctl table
  *
  * Returns true if the first position is non-zero and the sysctl_writes_strict
  * mode indicates this is not allowed for numeric input types. String proc
  * handlers can ignore the return value.
  */
 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
                        struct ctl_table *table)
 {
     if (!*ppos)
         return false;
 
     switch (sysctl_writes_strict) {
     case SYSCTL_WRITES_STRICT:
         return true;
     case SYSCTL_WRITES_WARN:
         warn_sysctl_write(table);
         return false;
     default:
         return false;
     }
 }
 
 /**
  * proc_dostring - read a string sysctl
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes a string from/to the user buffer. If the kernel
  * buffer provided is not large enough to hold the string, the
  * string is truncated. The copied string is %NULL-terminated.
  * If the string is being read by the user process, it is copied
  * and a newline '\n' is added. It is truncated if the buffer is
  * not large enough.
  *
  * Returns 0 on success.
  */
 int proc_dostring(struct ctl_table *table, int write,
           void *buffer, size_t *lenp, loff_t *ppos)
 {
     if (write)
         proc_first_pos_non_zero_ignore(ppos, table);
 
     return _proc_do_string(table->data, table->maxlen, write, buffer, lenp,
             ppos);
 }
 
 static size_t proc_skip_spaces(char **buf)
 {
     size_t ret;
     char *tmp = skip_spaces(*buf);
     ret = tmp - *buf;
     *buf = tmp;
     return ret;
 }
 
 static void proc_skip_char(char **buf, size_t *size, const char v)
 {
     while (*size) {
         if (**buf != v)
             break;
         (*size)--;
         (*buf)++;
     }
 }
 
 /**
  * strtoul_lenient - parse an ASCII formatted integer from a buffer and only
  *                   fail on overflow
  *
  * @cp: kernel buffer containing the string to parse
  * @endp: pointer to store the trailing characters
  * @base: the base to use
  * @res: where the parsed integer will be stored
  *
  * In case of success 0 is returned and @res will contain the parsed integer,
  * @endp will hold any trailing characters.
  * This function will fail the parse on overflow. If there wasn't an overflow
  * the function will defer the decision what characters count as invalid to the
  * caller.
  */
 static int strtoul_lenient(const char *cp, char **endp, unsigned int base,
                unsigned long *res)
 {
     unsigned long long result;
     unsigned int rv;
 
     cp = _parse_integer_fixup_radix(cp, &base);
     rv = _parse_integer(cp, base, &result);
     if ((rv & KSTRTOX_OVERFLOW) || (result != (unsigned long)result))
         return -ERANGE;
 
     cp += rv;
 
     if (endp)
         *endp = (char *)cp;
 
     *res = (unsigned long)result;
     return 0;
 }
 
 #define TMPBUFLEN 22
 /**
  * proc_get_long - reads an ASCII formatted integer from a user buffer
  *
  * @buf: a kernel buffer
  * @size: size of the kernel buffer
  * @val: this is where the number will be stored
  * @neg: set to %TRUE if number is negative
  * @perm_tr: a vector which contains the allowed trailers
  * @perm_tr_len: size of the perm_tr vector
  * @tr: pointer to store the trailer character
  *
  * In case of success %0 is returned and @buf and @size are updated with
  * the amount of bytes read. If @tr is non-NULL and a trailing
  * character exists (size is non-zero after returning from this
  * function), @tr is updated with the trailing character.
  */
 static int proc_get_long(char **buf, size_t *size,
               unsigned long *val, bool *neg,
               const char *perm_tr, unsigned perm_tr_len, char *tr)
 {
     int len;
     char *p, tmp[TMPBUFLEN];
 
     if (!*size)
         return -EINVAL;
 
     len = *size;
     if (len > TMPBUFLEN - 1)
         len = TMPBUFLEN - 1;
 
     memcpy(tmp, *buf, len);
 
     tmp[len] = 0;
     p = tmp;
     if (*p == '-' && *size > 1) {
         *neg = true;
         p++;
     } else
         *neg = false;
     if (!isdigit(*p))
         return -EINVAL;
 
     if (strtoul_lenient(p, &p, 0, val))
         return -EINVAL;
 
     len = p - tmp;
 
     /* We don't know if the next char is whitespace thus we may accept
      * invalid integers (e.g. 1234...a) or two integers instead of one
      * (e.g. 123...1). So lets not allow such large numbers. */
     if (len == TMPBUFLEN - 1)
         return -EINVAL;
 
     if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
         return -EINVAL;
 
     if (tr && (len < *size))
         *tr = *p;
 
     *buf += len;
     *size -= len;
 
     return 0;
 }
 
 /**
  * proc_put_long - converts an integer to a decimal ASCII formatted string
  *
  * @buf: the user buffer
  * @size: the size of the user buffer
  * @val: the integer to be converted
  * @neg: sign of the number, %TRUE for negative
  *
  * In case of success @buf and @size are updated with the amount of bytes
  * written.
  */
 static void proc_put_long(void **buf, size_t *size, unsigned long val, bool neg)
 {
     int len;
     char tmp[TMPBUFLEN], *p = tmp;
 
     sprintf(p, "%s%lu", neg ? "-" : "", val);
     len = strlen(tmp);
     if (len > *size)
         len = *size;
     memcpy(*buf, tmp, len);
     *size -= len;
     *buf += len;
 }
 #undef TMPBUFLEN
 
 static void proc_put_char(void **buf, size_t *size, char c)
 {
     if (*size) {
         char **buffer = (char **)buf;
         **buffer = c;
 
         (*size)--;
         (*buffer)++;
         *buf = *buffer;
     }
 }
 
 static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp,
                 int *valp,
                 int write, void *data)
 {
     if (write) {
         *(bool *)valp = *lvalp;
     } else {
         int val = *(bool *)valp;
 
         *lvalp = (unsigned long)val;
         *negp = false;
     }
     return 0;
 }
 
 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
                  int *valp,
                  int write, void *data)
 {
     if (write) {
         if (*negp) {
             if (*lvalp > (unsigned long) INT_MAX + 1)
                 return -EINVAL;
             WRITE_ONCE(*valp, -*lvalp);
         } else {
             if (*lvalp > (unsigned long) INT_MAX)
                 return -EINVAL;
             WRITE_ONCE(*valp, *lvalp);
         }
     } else {
         int val = READ_ONCE(*valp);
         if (val < 0) {
             *negp = true;
             *lvalp = -(unsigned long)val;
         } else {
             *negp = false;
             *lvalp = (unsigned long)val;
         }
     }
     return 0;
 }
 
 static int do_proc_douintvec_conv(unsigned long *lvalp,
                   unsigned int *valp,
                   int write, void *data)
 {
     if (write) {
         if (*lvalp > UINT_MAX)
             return -EINVAL;
         WRITE_ONCE(*valp, *lvalp);
     } else {
         unsigned int val = READ_ONCE(*valp);
         *lvalp = (unsigned long)val;
     }
     return 0;
 }
 
 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
 
 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
           int write, void *buffer,
           size_t *lenp, loff_t *ppos,
           int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
                   int write, void *data),
           void *data)
 {
     int *i, vleft, first = 1, err = 0;
     size_t left;
     char *p;
 
     if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
         *lenp = 0;
         return 0;
     }
 
     i = (int *) tbl_data;
     vleft = table->maxlen / sizeof(*i);
     left = *lenp;
 
     if (!conv)
         conv = do_proc_dointvec_conv;
 
     if (write) {
         if (proc_first_pos_non_zero_ignore(ppos, table))
             goto out;
 
         if (left > PAGE_SIZE - 1)
             left = PAGE_SIZE - 1;
         p = buffer;
     }
 
     for (; left && vleft--; i++, first=0) {
         unsigned long lval;
         bool neg;
 
         if (write) {
             left -= proc_skip_spaces(&p);
 
             if (!left)
                 break;
             err = proc_get_long(&p, &left, &lval, &neg,
                          proc_wspace_sep,
                          sizeof(proc_wspace_sep), NULL);
             if (err)
                 break;
             if (conv(&neg, &lval, i, 1, data)) {
                 err = -EINVAL;
                 break;
             }
         } else {
             if (conv(&neg, &lval, i, 0, data)) {
                 err = -EINVAL;
                 break;
             }
             if (!first)
                 proc_put_char(&buffer, &left, '\t');
             proc_put_long(&buffer, &left, lval, neg);
         }
     }
 
     if (!write && !first && left && !err)
         proc_put_char(&buffer, &left, '\n');
     if (write && !err && left)
         left -= proc_skip_spaces(&p);
     if (write && first)
         return err ? : -EINVAL;
     *lenp -= left;
 out:
     *ppos += *lenp;
     return err;
 }
 
 static int do_proc_dointvec(struct ctl_table *table, int write,
           void *buffer, size_t *lenp, loff_t *ppos,
           int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
                   int write, void *data),
           void *data)
 {
     return __do_proc_dointvec(table->data, table, write,
             buffer, lenp, ppos, conv, data);
 }
 
 static int do_proc_douintvec_w(unsigned int *tbl_data,
                    struct ctl_table *table,
                    void *buffer,
                    size_t *lenp, loff_t *ppos,
                    int (*conv)(unsigned long *lvalp,
                        unsigned int *valp,
                        int write, void *data),
                    void *data)
 {
     unsigned long lval;
     int err = 0;
     size_t left;
     bool neg;
     char *p = buffer;
 
     left = *lenp;
 
     if (proc_first_pos_non_zero_ignore(ppos, table))
         goto bail_early;
 
     if (left > PAGE_SIZE - 1)
         left = PAGE_SIZE - 1;
 
     left -= proc_skip_spaces(&p);
     if (!left) {
         err = -EINVAL;
         goto out_free;
     }
 
     err = proc_get_long(&p, &left, &lval, &neg,
                  proc_wspace_sep,
                  sizeof(proc_wspace_sep), NULL);
     if (err || neg) {
         err = -EINVAL;
         goto out_free;
     }
 
     if (conv(&lval, tbl_data, 1, data)) {
         err = -EINVAL;
         goto out_free;
     }
 
     if (!err && left)
         left -= proc_skip_spaces(&p);
 
 out_free:
     if (err)
         return -EINVAL;
 
     return 0;
 
     /* This is in keeping with old __do_proc_dointvec() */
 bail_early:
     *ppos += *lenp;
     return err;
 }
 
 static int do_proc_douintvec_r(unsigned int *tbl_data, void *buffer,
                    size_t *lenp, loff_t *ppos,
                    int (*conv)(unsigned long *lvalp,
                        unsigned int *valp,
                        int write, void *data),
                    void *data)
 {
     unsigned long lval;
     int err = 0;
     size_t left;
 
     left = *lenp;
 
     if (conv(&lval, tbl_data, 0, data)) {
         err = -EINVAL;
         goto out;
     }
 
     proc_put_long(&buffer, &left, lval, false);
     if (!left)
         goto out;
 
     proc_put_char(&buffer, &left, '\n');
 
 out:
     *lenp -= left;
     *ppos += *lenp;
 
     return err;
 }
 
 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
                    int write, void *buffer,
                    size_t *lenp, loff_t *ppos,
                    int (*conv)(unsigned long *lvalp,
                        unsigned int *valp,
                        int write, void *data),
                    void *data)
 {
     unsigned int *i, vleft;
 
     if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
         *lenp = 0;
         return 0;
     }
 
     i = (unsigned int *) tbl_data;
     vleft = table->maxlen / sizeof(*i);
 
     /*
      * Arrays are not supported, keep this simple. *Do not* add
      * support for them.
      */
     if (vleft != 1) {
         *lenp = 0;
         return -EINVAL;
     }
 
     if (!conv)
         conv = do_proc_douintvec_conv;
 
     if (write)
         return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
                        conv, data);
     return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
 }
 
 int do_proc_douintvec(struct ctl_table *table, int write,
               void *buffer, size_t *lenp, loff_t *ppos,
               int (*conv)(unsigned long *lvalp,
                   unsigned int *valp,
                   int write, void *data),
               void *data)
 {
     return __do_proc_douintvec(table->data, table, write,
                    buffer, lenp, ppos, conv, data);
 }
 
 /**
  * proc_dobool - read/write a bool
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
  * values from/to the user buffer, treated as an ASCII string.
  *
  * Returns 0 on success.
  */
 int proc_dobool(struct ctl_table *table, int write, void *buffer,
         size_t *lenp, loff_t *ppos)
 {
     return do_proc_dointvec(table, write, buffer, lenp, ppos,
                 do_proc_dobool_conv, NULL);
 }
 
 /**
  * proc_dointvec - read a vector of integers
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
  * values from/to the user buffer, treated as an ASCII string.
  *
  * Returns 0 on success.
  */
 int proc_dointvec(struct ctl_table *table, int write, void *buffer,
           size_t *lenp, loff_t *ppos)
 {
     return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
 }
 
 #ifdef CONFIG_COMPACTION
 static int proc_dointvec_minmax_warn_RT_change(struct ctl_table *table,
         int write, void *buffer, size_t *lenp, loff_t *ppos)
 {
     int ret, old;
 
     if (!IS_ENABLED(CONFIG_PREEMPT_RT) || !write)
         return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 
     old = *(int *)table->data;
     ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
     if (ret)
         return ret;
     if (old != *(int *)table->data)
         pr_warn_once("sysctl attribute %s changed by %s[%d]\n",
                  table->procname, current->comm,
                  task_pid_nr(current));
     return ret;
 }
 #endif
 
 /**
  * proc_douintvec - read a vector of unsigned integers
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
  * values from/to the user buffer, treated as an ASCII string.
  *
  * Returns 0 on success.
  */
 int proc_douintvec(struct ctl_table *table, int write, void *buffer,
         size_t *lenp, loff_t *ppos)
 {
     return do_proc_douintvec(table, write, buffer, lenp, ppos,
                  do_proc_douintvec_conv, NULL);
 }
 
 /*
  * Taint values can only be increased
  * This means we can safely use a temporary.
  */
 static int proc_taint(struct ctl_table *table, int write,
                    void *buffer, size_t *lenp, loff_t *ppos)
 {
     struct ctl_table t;
     unsigned long tmptaint = get_taint();
     int err;
 
     if (write && !capable(CAP_SYS_ADMIN))
         return -EPERM;
 
     t = *table;
     t.data = &tmptaint;
     err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
     if (err < 0)
         return err;
 
     if (write) {
         int i;
 
         /*
          * If we are relying on panic_on_taint not producing
          * false positives due to userspace input, bail out
          * before setting the requested taint flags.
          */
         if (panic_on_taint_nousertaint && (tmptaint & panic_on_taint))
             return -EINVAL;
 
         /*
          * Poor man's atomic or. Not worth adding a primitive
          * to everyone's atomic.h for this
          */
         for (i = 0; i < TAINT_FLAGS_COUNT; i++)
             if ((1UL << i) & tmptaint)
                 add_taint(i, LOCKDEP_STILL_OK);
     }
 
     return err;
 }
 
 /**
  * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
  * @min: pointer to minimum allowable value
  * @max: pointer to maximum allowable value
  *
  * The do_proc_dointvec_minmax_conv_param structure provides the
  * minimum and maximum values for doing range checking for those sysctl
  * parameters that use the proc_dointvec_minmax() handler.
  */
 struct do_proc_dointvec_minmax_conv_param {
     int *min;
     int *max;
 };
 
 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
                     int *valp,
                     int write, void *data)
 {
     int tmp, ret;
     struct do_proc_dointvec_minmax_conv_param *param = data;
     /*
      * If writing, first do so via a temporary local int so we can
      * bounds-check it before touching *valp.
      */
     int *ip = write ? &tmp : valp;
 
     ret = do_proc_dointvec_conv(negp, lvalp, ip, write, data);
     if (ret)
         return ret;
 
     if (write) {
         if ((param->min && *param->min > tmp) ||
             (param->max && *param->max < tmp))
             return -EINVAL;
         WRITE_ONCE(*valp, tmp);
     }
 
     return 0;
 }
 
 /**
  * proc_dointvec_minmax - read a vector of integers with min/max values
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
  * values from/to the user buffer, treated as an ASCII string.
  *
  * This routine will ensure the values are within the range specified by
  * table->extra1 (min) and table->extra2 (max).
  *
  * Returns 0 on success or -EINVAL on write when the range check fails.
  */
 int proc_dointvec_minmax(struct ctl_table *table, int write,
           void *buffer, size_t *lenp, loff_t *ppos)
 {
     struct do_proc_dointvec_minmax_conv_param param = {
         .min = (int *) table->extra1,
         .max = (int *) table->extra2,
     };
     return do_proc_dointvec(table, write, buffer, lenp, ppos,
                 do_proc_dointvec_minmax_conv, &param);
 }
 
 /**
  * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
  * @min: pointer to minimum allowable value
  * @max: pointer to maximum allowable value
  *
  * The do_proc_douintvec_minmax_conv_param structure provides the
  * minimum and maximum values for doing range checking for those sysctl
  * parameters that use the proc_douintvec_minmax() handler.
  */
 struct do_proc_douintvec_minmax_conv_param {
     unsigned int *min;
     unsigned int *max;
 };
 
 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
                      unsigned int *valp,
                      int write, void *data)
 {
     int ret;
     unsigned int tmp;
     struct do_proc_douintvec_minmax_conv_param *param = data;
     /* write via temporary local uint for bounds-checking */
     unsigned int *up = write ? &tmp : valp;
 
     ret = do_proc_douintvec_conv(lvalp, up, write, data);
     if (ret)
         return ret;
 
     if (write) {
         if ((param->min && *param->min > tmp) ||
             (param->max && *param->max < tmp))
             return -ERANGE;
 
         WRITE_ONCE(*valp, tmp);
     }
 
     return 0;
 }
 
 /**
  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
  * values from/to the user buffer, treated as an ASCII string. Negative
  * strings are not allowed.
  *
  * This routine will ensure the values are within the range specified by
  * table->extra1 (min) and table->extra2 (max). There is a final sanity
  * check for UINT_MAX to avoid having to support wrap around uses from
  * userspace.
  *
  * Returns 0 on success or -ERANGE on write when the range check fails.
  */
 int proc_douintvec_minmax(struct ctl_table *table, int write,
               void *buffer, size_t *lenp, loff_t *ppos)
 {
     struct do_proc_douintvec_minmax_conv_param param = {
         .min = (unsigned int *) table->extra1,
         .max = (unsigned int *) table->extra2,
     };
     return do_proc_douintvec(table, write, buffer, lenp, ppos,
                  do_proc_douintvec_minmax_conv, &param);
 }
 
 /**
  * proc_dou8vec_minmax - read a vector of unsigned chars with min/max values
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(u8) unsigned chars
  * values from/to the user buffer, treated as an ASCII string. Negative
  * strings are not allowed.
  *
  * This routine will ensure the values are within the range specified by
  * table->extra1 (min) and table->extra2 (max).
  *
  * Returns 0 on success or an error on write when the range check fails.
  */
 int proc_dou8vec_minmax(struct ctl_table *table, int write,
             void *buffer, size_t *lenp, loff_t *ppos)
 {
     struct ctl_table tmp;
     unsigned int min = 0, max = 255U, val;
     u8 *data = table->data;
     struct do_proc_douintvec_minmax_conv_param param = {
         .min = &min,
         .max = &max,
     };
     int res;
 
     /* Do not support arrays yet. */
     if (table->maxlen != sizeof(u8))
         return -EINVAL;
 
     if (table->extra1) {
         min = *(unsigned int *) table->extra1;
         if (min > 255U)
             return -EINVAL;
     }
     if (table->extra2) {
         max = *(unsigned int *) table->extra2;
         if (max > 255U)
             return -EINVAL;
     }
 
     tmp = *table;
 
     tmp.maxlen = sizeof(val);
     tmp.data = &val;
     val = READ_ONCE(*data);
     res = do_proc_douintvec(&tmp, write, buffer, lenp, ppos,
                 do_proc_douintvec_minmax_conv, &param);
     if (res)
         return res;
     if (write)
         WRITE_ONCE(*data, val);
     return 0;
 }
 EXPORT_SYMBOL_GPL(proc_dou8vec_minmax);
 
 #ifdef CONFIG_MAGIC_SYSRQ
 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
                 void *buffer, size_t *lenp, loff_t *ppos)
 {
     int tmp, ret;
 
     tmp = sysrq_mask();
 
     ret = __do_proc_dointvec(&tmp, table, write, buffer,
                    lenp, ppos, NULL, NULL);
     if (ret || !write)
         return ret;
 
     if (write)
         sysrq_toggle_support(tmp);
 
     return 0;
 }
 #endif
 
 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table,
         int write, void *buffer, size_t *lenp, loff_t *ppos,
         unsigned long convmul, unsigned long convdiv)
 {
     unsigned long *i, *min, *max;
     int vleft, first = 1, err = 0;
     size_t left;
     char *p;
 
     if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
         *lenp = 0;
         return 0;
     }
 
     i = (unsigned long *) data;
     min = (unsigned long *) table->extra1;
     max = (unsigned long *) table->extra2;
     vleft = table->maxlen / sizeof(unsigned long);
     left = *lenp;
 
     if (write) {
         if (proc_first_pos_non_zero_ignore(ppos, table))
             goto out;
 
         if (left > PAGE_SIZE - 1)
             left = PAGE_SIZE - 1;
         p = buffer;
     }
 
     for (; left && vleft--; i++, first = 0) {
         unsigned long val;
 
         if (write) {
             bool neg;
 
             left -= proc_skip_spaces(&p);
             if (!left)
                 break;
 
             err = proc_get_long(&p, &left, &val, &neg,
                          proc_wspace_sep,
                          sizeof(proc_wspace_sep), NULL);
             if (err || neg) {
                 err = -EINVAL;
                 break;
             }
 
             val = convmul * val / convdiv;
             if ((min && val < *min) || (max && val > *max)) {
                 err = -EINVAL;
                 break;
             }
             WRITE_ONCE(*i, val);
         } else {
             val = convdiv * READ_ONCE(*i) / convmul;
             if (!first)
                 proc_put_char(&buffer, &left, '\t');
             proc_put_long(&buffer, &left, val, false);
         }
     }
 
     if (!write && !first && left && !err)
         proc_put_char(&buffer, &left, '\n');
     if (write && !err)
         left -= proc_skip_spaces(&p);
     if (write && first)
         return err ? : -EINVAL;
     *lenp -= left;
 out:
     *ppos += *lenp;
     return err;
 }
 
 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
         void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul,
         unsigned long convdiv)
 {
     return __do_proc_doulongvec_minmax(table->data, table, write,
             buffer, lenp, ppos, convmul, convdiv);
 }
 
 /**
  * proc_doulongvec_minmax - read a vector of long integers with min/max values
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
  * values from/to the user buffer, treated as an ASCII string.
  *
  * This routine will ensure the values are within the range specified by
  * table->extra1 (min) and table->extra2 (max).
  *
  * Returns 0 on success.
  */
 int proc_doulongvec_minmax(struct ctl_table *table, int write,
                void *buffer, size_t *lenp, loff_t *ppos)
 {
     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
 }
 
 /**
  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
  * values from/to the user buffer, treated as an ASCII string. The values
  * are treated as milliseconds, and converted to jiffies when they are stored.
  *
  * This routine will ensure the values are within the range specified by
  * table->extra1 (min) and table->extra2 (max).
  *
  * Returns 0 on success.
  */
 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
                       void *buffer, size_t *lenp, loff_t *ppos)
 {
     return do_proc_doulongvec_minmax(table, write, buffer,
                      lenp, ppos, HZ, 1000l);
 }
 
 
 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
                      int *valp,
                      int write, void *data)
 {
     if (write) {
         if (*lvalp > INT_MAX / HZ)
             return 1;
         if (*negp)
             WRITE_ONCE(*valp, -*lvalp * HZ);
         else
             WRITE_ONCE(*valp, *lvalp * HZ);
     } else {
         int val = READ_ONCE(*valp);
         unsigned long lval;
         if (val < 0) {
             *negp = true;
             lval = -(unsigned long)val;
         } else {
             *negp = false;
             lval = (unsigned long)val;
         }
         *lvalp = lval / HZ;
     }
     return 0;
 }
 
 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
                         int *valp,
                         int write, void *data)
 {
     if (write) {
         if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
             return 1;
         *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
     } else {
         int val = *valp;
         unsigned long lval;
         if (val < 0) {
             *negp = true;
             lval = -(unsigned long)val;
         } else {
             *negp = false;
             lval = (unsigned long)val;
         }
         *lvalp = jiffies_to_clock_t(lval);
     }
     return 0;
 }
 
 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
                         int *valp,
                         int write, void *data)
 {
     if (write) {
         unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
 
         if (jif > INT_MAX)
             return 1;
         WRITE_ONCE(*valp, (int)jif);
     } else {
         int val = READ_ONCE(*valp);
         unsigned long lval;
         if (val < 0) {
             *negp = true;
             lval = -(unsigned long)val;
         } else {
             *negp = false;
             lval = (unsigned long)val;
         }
         *lvalp = jiffies_to_msecs(lval);
     }
     return 0;
 }
 
 static int do_proc_dointvec_ms_jiffies_minmax_conv(bool *negp, unsigned long *lvalp,
                         int *valp, int write, void *data)
 {
     int tmp, ret;
     struct do_proc_dointvec_minmax_conv_param *param = data;
     /*
      * If writing, first do so via a temporary local int so we can
      * bounds-check it before touching *valp.
      */
     int *ip = write ? &tmp : valp;
 
     ret = do_proc_dointvec_ms_jiffies_conv(negp, lvalp, ip, write, data);
     if (ret)
         return ret;
 
     if (write) {
         if ((param->min && *param->min > tmp) ||
                 (param->max && *param->max < tmp))
             return -EINVAL;
         *valp = tmp;
     }
     return 0;
 }
 
 /**
  * proc_dointvec_jiffies - read a vector of integers as seconds
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
  * values from/to the user buffer, treated as an ASCII string.
  * The values read are assumed to be in seconds, and are converted into
  * jiffies.
  *
  * Returns 0 on success.
  */
 int proc_dointvec_jiffies(struct ctl_table *table, int write,
               void *buffer, size_t *lenp, loff_t *ppos)
 {
     return do_proc_dointvec(table,write,buffer,lenp,ppos,
                     do_proc_dointvec_jiffies_conv,NULL);
 }
 
 int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
               void *buffer, size_t *lenp, loff_t *ppos)
 {
     struct do_proc_dointvec_minmax_conv_param param = {
         .min = (int *) table->extra1,
         .max = (int *) table->extra2,
     };
     return do_proc_dointvec(table, write, buffer, lenp, ppos,
             do_proc_dointvec_ms_jiffies_minmax_conv, &param);
 }
 
 /**
  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: pointer to the file position
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
  * values from/to the user buffer, treated as an ASCII string.
  * The values read are assumed to be in 1/USER_HZ seconds, and
  * are converted into jiffies.
  *
  * Returns 0 on success.
  */
 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
                  void *buffer, size_t *lenp, loff_t *ppos)
 {
     return do_proc_dointvec(table, write, buffer, lenp, ppos,
                 do_proc_dointvec_userhz_jiffies_conv, NULL);
 }
 
 /**
  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  * @ppos: the current position in the file
  *
  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
  * values from/to the user buffer, treated as an ASCII string.
  * The values read are assumed to be in 1/1000 seconds, and
  * are converted into jiffies.
  *
  * Returns 0 on success.
  */
 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, void *buffer,
         size_t *lenp, loff_t *ppos)
 {
     return do_proc_dointvec(table, write, buffer, lenp, ppos,
                 do_proc_dointvec_ms_jiffies_conv, NULL);
 }
 
 static int proc_do_cad_pid(struct ctl_table *table, int write, void *buffer,
         size_t *lenp, loff_t *ppos)
 {
     struct pid *new_pid;
     pid_t tmp;
     int r;
 
     tmp = pid_vnr(cad_pid);
 
     r = __do_proc_dointvec(&tmp, table, write, buffer,
                    lenp, ppos, NULL, NULL);
     if (r || !write)
         return r;
 
     new_pid = find_get_pid(tmp);
     if (!new_pid)
         return -ESRCH;
 
     put_pid(xchg(&cad_pid, new_pid));
     return 0;
 }
 
 /**
  * proc_do_large_bitmap - read/write from/to a large bitmap
  * @table: the sysctl table
  * @write: %TRUE if this is a write to the sysctl file
  * @buffer: the user buffer
  * @lenp: the size of the user buffer
  * @ppos: file position
  *
  * The bitmap is stored at table->data and the bitmap length (in bits)
  * in table->maxlen.
  *
  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
  * large bitmaps may be represented in a compact manner. Writing into
  * the file will clear the bitmap then update it with the given input.
  *
  * Returns 0 on success.
  */
 int proc_do_large_bitmap(struct ctl_table *table, int write,
              void *buffer, size_t *lenp, loff_t *ppos)
 {
     int err = 0;
     size_t left = *lenp;
     unsigned long bitmap_len = table->maxlen;
     unsigned long *bitmap = *(unsigned long **) table->data;
     unsigned long *tmp_bitmap = NULL;
     char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
 
     if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
         *lenp = 0;
         return 0;
     }
 
     if (write) {
         char *p = buffer;
         size_t skipped = 0;
 
         if (left > PAGE_SIZE - 1) {
             left = PAGE_SIZE - 1;
             /* How much of the buffer we'll skip this pass */
             skipped = *lenp - left;
         }
 
         tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL);
         if (!tmp_bitmap)
             return -ENOMEM;
         proc_skip_char(&p, &left, '\n');
         while (!err && left) {
             unsigned long val_a, val_b;
             bool neg;
             size_t saved_left;
 
             /* In case we stop parsing mid-number, we can reset */
             saved_left = left;
             err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
                          sizeof(tr_a), &c);
             /*
              * If we consumed the entirety of a truncated buffer or
              * only one char is left (may be a "-"), then stop here,
              * reset, & come back for more.
              */
             if ((left <= 1) && skipped) {
                 left = saved_left;
                 break;
             }
 
             if (err)
                 break;
             if (val_a >= bitmap_len || neg) {
                 err = -EINVAL;
                 break;
             }
 
             val_b = val_a;
             if (left) {
                 p++;
                 left--;
             }
 
             if (c == '-') {
                 err = proc_get_long(&p, &left, &val_b,
                              &neg, tr_b, sizeof(tr_b),
                              &c);
                 /*
                  * If we consumed all of a truncated buffer or
                  * then stop here, reset, & come back for more.
                  */
                 if (!left && skipped) {
                     left = saved_left;
                     break;
                 }
 
                 if (err)
                     break;
                 if (val_b >= bitmap_len || neg ||
                     val_a > val_b) {
                     err = -EINVAL;
                     break;
                 }
                 if (left) {
                     p++;
                     left--;
                 }
             }
 
             bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
             proc_skip_char(&p, &left, '\n');
         }
         left += skipped;
     } else {
         unsigned long bit_a, bit_b = 0;
         bool first = 1;
 
         while (left) {
             bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
             if (bit_a >= bitmap_len)
                 break;
             bit_b = find_next_zero_bit(bitmap, bitmap_len,
                            bit_a + 1) - 1;
 
             if (!first)
                 proc_put_char(&buffer, &left, ',');
             proc_put_long(&buffer, &left, bit_a, false);
             if (bit_a != bit_b) {
                 proc_put_char(&buffer, &left, '-');
                 proc_put_long(&buffer, &left, bit_b, false);
             }
 
             first = 0; bit_b++;
         }
         proc_put_char(&buffer, &left, '\n');
     }
 
     if (!err) {
         if (write) {
             if (*ppos)
                 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
             else
                 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
         }
         *lenp -= left;
         *ppos += *lenp;
     }
 
     bitmap_free(tmp_bitmap);
     return err;
 }
 
 #else /* CONFIG_PROC_SYSCTL */
 
 int proc_dostring(struct ctl_table *table, int write,
           void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dobool(struct ctl_table *table, int write,
         void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dointvec(struct ctl_table *table, int write,
           void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_douintvec(struct ctl_table *table, int write,
           void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dointvec_minmax(struct ctl_table *table, int write,
             void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_douintvec_minmax(struct ctl_table *table, int write,
               void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dou8vec_minmax(struct ctl_table *table, int write,
             void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dointvec_jiffies(struct ctl_table *table, int write,
             void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
                     void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
             void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
                  void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_doulongvec_minmax(struct ctl_table *table, int write,
             void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
                       void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 int proc_do_large_bitmap(struct ctl_table *table, int write,
              void *buffer, size_t *lenp, loff_t *ppos)
 {
     return -ENOSYS;
 }
 
 #endif /* CONFIG_PROC_SYSCTL */
 
 #if defined(CONFIG_SYSCTL)
 int proc_do_static_key(struct ctl_table *table, int write,
                void *buffer, size_t *lenp, loff_t *ppos)
 {
     struct static_key *key = (struct static_key *)table->data;
     static DEFINE_MUTEX(static_key_mutex);
     int val, ret;
     struct ctl_table tmp = {
         .data   = &val,
         .maxlen = sizeof(val),
         .mode   = table->mode,
         .extra1 = SYSCTL_ZERO,
         .extra2 = SYSCTL_ONE,
     };
 
     if (write && !capable(CAP_SYS_ADMIN))
         return -EPERM;
 
     mutex_lock(&static_key_mutex);
     val = static_key_enabled(key);
     ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
     if (write && !ret) {
         if (val)
             static_key_enable(key);
         else
             static_key_disable(key);
     }
     mutex_unlock(&static_key_mutex);
     return ret;
 }
 
 static struct ctl_table kern_table[] = {
 #ifdef CONFIG_NUMA_BALANCING
     {
         .procname   = "numa_balancing",
         .data       = NULL, /* filled in by handler */
         .maxlen     = sizeof(unsigned int),
         .mode       = 0644,
         .proc_handler   = sysctl_numa_balancing,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_FOUR,
     },
 #endif /* CONFIG_NUMA_BALANCING */
     {
         .procname   = "panic",
         .data       = &panic_timeout,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #ifdef CONFIG_PROC_SYSCTL
     {
         .procname   = "tainted",
         .maxlen     = sizeof(long),
         .mode       = 0644,
         .proc_handler   = proc_taint,
     },
     {
         .procname   = "sysctl_writes_strict",
         .data       = &sysctl_writes_strict,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_NEG_ONE,
         .extra2     = SYSCTL_ONE,
     },
 #endif
     {
         .procname   = "print-fatal-signals",
         .data       = &print_fatal_signals,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #ifdef CONFIG_SPARC
     {
         .procname   = "reboot-cmd",
         .data       = reboot_command,
         .maxlen     = 256,
         .mode       = 0644,
         .proc_handler   = proc_dostring,
     },
     {
         .procname   = "stop-a",
         .data       = &stop_a_enabled,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "scons-poweroff",
         .data       = &scons_pwroff,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_SPARC64
     {
         .procname   = "tsb-ratio",
         .data       = &sysctl_tsb_ratio,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_PARISC
     {
         .procname   = "soft-power",
         .data       = &pwrsw_enabled,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
     {
         .procname   = "unaligned-trap",
         .data       = &unaligned_enabled,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_STACK_TRACER
     {
         .procname   = "stack_tracer_enabled",
         .data       = &stack_tracer_enabled,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = stack_trace_sysctl,
     },
 #endif
 #ifdef CONFIG_TRACING
     {
         .procname   = "ftrace_dump_on_oops",
         .data       = &ftrace_dump_on_oops,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "traceoff_on_warning",
         .data       = &__disable_trace_on_warning,
         .maxlen     = sizeof(__disable_trace_on_warning),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "tracepoint_printk",
         .data       = &tracepoint_printk,
         .maxlen     = sizeof(tracepoint_printk),
         .mode       = 0644,
         .proc_handler   = tracepoint_printk_sysctl,
     },
 #endif
 #ifdef CONFIG_MODULES
     {
         .procname   = "modprobe",
         .data       = &modprobe_path,
         .maxlen     = KMOD_PATH_LEN,
         .mode       = 0644,
         .proc_handler   = proc_dostring,
     },
     {
         .procname   = "modules_disabled",
         .data       = &modules_disabled,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         /* only handle a transition from default "0" to "1" */
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ONE,
         .extra2     = SYSCTL_ONE,
     },
 #endif
 #ifdef CONFIG_UEVENT_HELPER
     {
         .procname   = "hotplug",
         .data       = &uevent_helper,
         .maxlen     = UEVENT_HELPER_PATH_LEN,
         .mode       = 0644,
         .proc_handler   = proc_dostring,
     },
 #endif
 #ifdef CONFIG_MAGIC_SYSRQ
     {
         .procname   = "sysrq",
         .data       = NULL,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = sysrq_sysctl_handler,
     },
 #endif
 #ifdef CONFIG_PROC_SYSCTL
     {
         .procname   = "cad_pid",
         .data       = NULL,
         .maxlen     = sizeof (int),
         .mode       = 0600,
         .proc_handler   = proc_do_cad_pid,
     },
 #endif
     {
         .procname   = "threads-max",
         .data       = NULL,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = sysctl_max_threads,
     },
     {
         .procname   = "usermodehelper",
         .mode       = 0555,
         .child      = usermodehelper_table,
     },
     {
         .procname   = "overflowuid",
         .data       = &overflowuid,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_MAXOLDUID,
     },
     {
         .procname   = "overflowgid",
         .data       = &overflowgid,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_MAXOLDUID,
     },
 #ifdef CONFIG_S390
     {
         .procname   = "userprocess_debug",
         .data       = &show_unhandled_signals,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
     {
         .procname   = "pid_max",
         .data       = &pid_max,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = &pid_max_min,
         .extra2     = &pid_max_max,
     },
     {
         .procname   = "panic_on_oops",
         .data       = &panic_on_oops,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "panic_print",
         .data       = &panic_print,
         .maxlen     = sizeof(unsigned long),
         .mode       = 0644,
         .proc_handler   = proc_doulongvec_minmax,
     },
     {
         .procname   = "ngroups_max",
         .data       = (void *)&ngroups_max,
         .maxlen     = sizeof (int),
         .mode       = 0444,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "cap_last_cap",
         .data       = (void *)&cap_last_cap,
         .maxlen     = sizeof(int),
         .mode       = 0444,
         .proc_handler   = proc_dointvec,
     },
 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
     {
         .procname       = "unknown_nmi_panic",
         .data           = &unknown_nmi_panic,
         .maxlen         = sizeof (int),
         .mode           = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 
 #if (defined(CONFIG_X86_32) || defined(CONFIG_PARISC)) && \
     defined(CONFIG_DEBUG_STACKOVERFLOW)
     {
         .procname   = "panic_on_stackoverflow",
         .data       = &sysctl_panic_on_stackoverflow,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #if defined(CONFIG_X86)
     {
         .procname   = "panic_on_unrecovered_nmi",
         .data       = &panic_on_unrecovered_nmi,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "panic_on_io_nmi",
         .data       = &panic_on_io_nmi,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "bootloader_type",
         .data       = &bootloader_type,
         .maxlen     = sizeof (int),
         .mode       = 0444,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "bootloader_version",
         .data       = &bootloader_version,
         .maxlen     = sizeof (int),
         .mode       = 0444,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "io_delay_type",
         .data       = &io_delay_type,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #if defined(CONFIG_MMU)
     {
         .procname   = "randomize_va_space",
         .data       = &randomize_va_space,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
     {
         .procname   = "spin_retry",
         .data       = &spin_retry,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
     {
         .procname   = "acpi_video_flags",
         .data       = &acpi_realmode_flags,
         .maxlen     = sizeof (unsigned long),
         .mode       = 0644,
         .proc_handler   = proc_doulongvec_minmax,
     },
 #endif
 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
     {
         .procname   = "ignore-unaligned-usertrap",
         .data       = &no_unaligned_warning,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_IA64
     {
         .procname   = "unaligned-dump-stack",
         .data       = &unaligned_dump_stack,
         .maxlen     = sizeof (int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_RT_MUTEXES
     {
         .procname   = "max_lock_depth",
         .data       = &max_lock_depth,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
 #endif
 #ifdef CONFIG_KEYS
     {
         .procname   = "keys",
         .mode       = 0555,
         .child      = key_sysctls,
     },
 #endif
 #ifdef CONFIG_PERF_EVENTS
     /*
      * User-space scripts rely on the existence of this file
      * as a feature check for perf_events being enabled.
      *
      * So it's an ABI, do not remove!
      */
     {
         .procname   = "perf_event_paranoid",
         .data       = &sysctl_perf_event_paranoid,
         .maxlen     = sizeof(sysctl_perf_event_paranoid),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "perf_event_mlock_kb",
         .data       = &sysctl_perf_event_mlock,
         .maxlen     = sizeof(sysctl_perf_event_mlock),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
     },
     {
         .procname   = "perf_event_max_sample_rate",
         .data       = &sysctl_perf_event_sample_rate,
         .maxlen     = sizeof(sysctl_perf_event_sample_rate),
         .mode       = 0644,
         .proc_handler   = perf_proc_update_handler,
         .extra1     = SYSCTL_ONE,
     },
     {
         .procname   = "perf_cpu_time_max_percent",
         .data       = &sysctl_perf_cpu_time_max_percent,
         .maxlen     = sizeof(sysctl_perf_cpu_time_max_percent),
         .mode       = 0644,
         .proc_handler   = perf_cpu_time_max_percent_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE_HUNDRED,
     },
     {
         .procname   = "perf_event_max_stack",
         .data       = &sysctl_perf_event_max_stack,
         .maxlen     = sizeof(sysctl_perf_event_max_stack),
         .mode       = 0644,
         .proc_handler   = perf_event_max_stack_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = (void *)&six_hundred_forty_kb,
     },
     {
         .procname   = "perf_event_max_contexts_per_stack",
         .data       = &sysctl_perf_event_max_contexts_per_stack,
         .maxlen     = sizeof(sysctl_perf_event_max_contexts_per_stack),
         .mode       = 0644,
         .proc_handler   = perf_event_max_stack_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE_THOUSAND,
     },
 #endif
     {
         .procname   = "panic_on_warn",
         .data       = &panic_on_warn,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
 #ifdef CONFIG_TREE_RCU
     {
         .procname   = "panic_on_rcu_stall",
         .data       = &sysctl_panic_on_rcu_stall,
         .maxlen     = sizeof(sysctl_panic_on_rcu_stall),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
     {
         .procname   = "max_rcu_stall_to_panic",
         .data       = &sysctl_max_rcu_stall_to_panic,
         .maxlen     = sizeof(sysctl_max_rcu_stall_to_panic),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ONE,
         .extra2     = SYSCTL_INT_MAX,
     },
 #endif
     { }
 };
 
 static struct ctl_table vm_table[] = {
     {
         .procname   = "overcommit_memory",
         .data       = &sysctl_overcommit_memory,
         .maxlen     = sizeof(sysctl_overcommit_memory),
         .mode       = 0644,
         .proc_handler   = overcommit_policy_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_TWO,
     },
     {
         .procname   = "overcommit_ratio",
         .data       = &sysctl_overcommit_ratio,
         .maxlen     = sizeof(sysctl_overcommit_ratio),
         .mode       = 0644,
         .proc_handler   = overcommit_ratio_handler,
     },
     {
         .procname   = "overcommit_kbytes",
         .data       = &sysctl_overcommit_kbytes,
         .maxlen     = sizeof(sysctl_overcommit_kbytes),
         .mode       = 0644,
         .proc_handler   = overcommit_kbytes_handler,
     },
     {
         .procname   = "page-cluster",
         .data       = &page_cluster,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
     {
         .procname   = "dirtytime_expire_seconds",
         .data       = &dirtytime_expire_interval,
         .maxlen     = sizeof(dirtytime_expire_interval),
         .mode       = 0644,
         .proc_handler   = dirtytime_interval_handler,
         .extra1     = SYSCTL_ZERO,
     },
     {
         .procname   = "swappiness",
         .data       = &vm_swappiness,
         .maxlen     = sizeof(vm_swappiness),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_TWO_HUNDRED,
     },
 #ifdef CONFIG_NUMA
     {
         .procname   = "numa_stat",
         .data       = &sysctl_vm_numa_stat,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = sysctl_vm_numa_stat_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
 #endif
 #ifdef CONFIG_HUGETLB_PAGE
     {
         .procname   = "nr_hugepages",
         .data       = NULL,
         .maxlen     = sizeof(unsigned long),
         .mode       = 0644,
         .proc_handler   = hugetlb_sysctl_handler,
     },
 #ifdef CONFIG_NUMA
     {
         .procname       = "nr_hugepages_mempolicy",
         .data           = NULL,
         .maxlen         = sizeof(unsigned long),
         .mode           = 0644,
         .proc_handler   = &hugetlb_mempolicy_sysctl_handler,
     },
 #endif
      {
         .procname   = "hugetlb_shm_group",
         .data       = &sysctl_hugetlb_shm_group,
         .maxlen     = sizeof(gid_t),
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
      },
     {
         .procname   = "nr_overcommit_hugepages",
         .data       = NULL,
         .maxlen     = sizeof(unsigned long),
         .mode       = 0644,
         .proc_handler   = hugetlb_overcommit_handler,
     },
 #endif
     {
         .procname   = "lowmem_reserve_ratio",
         .data       = &sysctl_lowmem_reserve_ratio,
         .maxlen     = sizeof(sysctl_lowmem_reserve_ratio),
         .mode       = 0644,
         .proc_handler   = lowmem_reserve_ratio_sysctl_handler,
     },
     {
         .procname   = "drop_caches",
         .data       = &sysctl_drop_caches,
         .maxlen     = sizeof(int),
         .mode       = 0200,
         .proc_handler   = drop_caches_sysctl_handler,
         .extra1     = SYSCTL_ONE,
         .extra2     = SYSCTL_FOUR,
     },
 #ifdef CONFIG_COMPACTION
     {
         .procname   = "compact_memory",
         .data       = NULL,
         .maxlen     = sizeof(int),
         .mode       = 0200,
         .proc_handler   = sysctl_compaction_handler,
     },
     {
         .procname   = "compaction_proactiveness",
         .data       = &sysctl_compaction_proactiveness,
         .maxlen     = sizeof(sysctl_compaction_proactiveness),
         .mode       = 0644,
         .proc_handler   = compaction_proactiveness_sysctl_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE_HUNDRED,
     },
     {
         .procname   = "extfrag_threshold",
         .data       = &sysctl_extfrag_threshold,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = (void *)&max_extfrag_threshold,
     },
     {
         .procname   = "compact_unevictable_allowed",
         .data       = &sysctl_compact_unevictable_allowed,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax_warn_RT_change,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
 
 #endif /* CONFIG_COMPACTION */
     {
         .procname   = "min_free_kbytes",
         .data       = &min_free_kbytes,
         .maxlen     = sizeof(min_free_kbytes),
         .mode       = 0644,
         .proc_handler   = min_free_kbytes_sysctl_handler,
         .extra1     = SYSCTL_ZERO,
     },
     {
         .procname   = "watermark_boost_factor",
         .data       = &watermark_boost_factor,
         .maxlen     = sizeof(watermark_boost_factor),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
     {
         .procname   = "watermark_scale_factor",
         .data       = &watermark_scale_factor,
         .maxlen     = sizeof(watermark_scale_factor),
         .mode       = 0644,
         .proc_handler   = watermark_scale_factor_sysctl_handler,
         .extra1     = SYSCTL_ONE,
         .extra2     = SYSCTL_THREE_THOUSAND,
     },
     {
         .procname   = "percpu_pagelist_high_fraction",
         .data       = &percpu_pagelist_high_fraction,
         .maxlen     = sizeof(percpu_pagelist_high_fraction),
         .mode       = 0644,
         .proc_handler   = percpu_pagelist_high_fraction_sysctl_handler,
         .extra1     = SYSCTL_ZERO,
     },
     {
         .procname   = "page_lock_unfairness",
         .data       = &sysctl_page_lock_unfairness,
         .maxlen     = sizeof(sysctl_page_lock_unfairness),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
 #ifdef CONFIG_MMU
     {
         .procname   = "max_map_count",
         .data       = &sysctl_max_map_count,
         .maxlen     = sizeof(sysctl_max_map_count),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
 #else
     {
         .procname   = "nr_trim_pages",
         .data       = &sysctl_nr_trim_pages,
         .maxlen     = sizeof(sysctl_nr_trim_pages),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
 #endif
     {
         .procname   = "vfs_cache_pressure",
         .data       = &sysctl_vfs_cache_pressure,
         .maxlen     = sizeof(sysctl_vfs_cache_pressure),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
     defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
     {
         .procname   = "legacy_va_layout",
         .data       = &sysctl_legacy_va_layout,
         .maxlen     = sizeof(sysctl_legacy_va_layout),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
 #endif
 #ifdef CONFIG_NUMA
     {
         .procname   = "zone_reclaim_mode",
         .data       = &node_reclaim_mode,
         .maxlen     = sizeof(node_reclaim_mode),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
     },
     {
         .procname   = "min_unmapped_ratio",
         .data       = &sysctl_min_unmapped_ratio,
         .maxlen     = sizeof(sysctl_min_unmapped_ratio),
         .mode       = 0644,
         .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE_HUNDRED,
     },
     {
         .procname   = "min_slab_ratio",
         .data       = &sysctl_min_slab_ratio,
         .maxlen     = sizeof(sysctl_min_slab_ratio),
         .mode       = 0644,
         .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE_HUNDRED,
     },
 #endif
 #ifdef CONFIG_SMP
     {
         .procname   = "stat_interval",
         .data       = &sysctl_stat_interval,
         .maxlen     = sizeof(sysctl_stat_interval),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_jiffies,
     },
     {
         .procname   = "stat_refresh",
         .data       = NULL,
         .maxlen     = 0,
         .mode       = 0600,
         .proc_handler   = vmstat_refresh,
     },
 #endif
 #ifdef CONFIG_MMU
     {
         .procname   = "mmap_min_addr",
         .data       = &dac_mmap_min_addr,
         .maxlen     = sizeof(unsigned long),
         .mode       = 0644,
         .proc_handler   = mmap_min_addr_handler,
     },
 #endif
 #ifdef CONFIG_NUMA
     {
         .procname   = "numa_zonelist_order",
         .data       = &numa_zonelist_order,
         .maxlen     = NUMA_ZONELIST_ORDER_LEN,
         .mode       = 0644,
         .proc_handler   = numa_zonelist_order_handler,
     },
 #endif
 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
     {
         .procname   = "vdso_enabled",
 #ifdef CONFIG_X86_32
         .data       = &vdso32_enabled,
         .maxlen     = sizeof(vdso32_enabled),
 #else
         .data       = &vdso_enabled,
         .maxlen     = sizeof(vdso_enabled),
 #endif
         .mode       = 0644,
         .proc_handler   = proc_dointvec,
         .extra1     = SYSCTL_ZERO,
     },
 #endif
 #ifdef CONFIG_MEMORY_FAILURE
     {
         .procname   = "memory_failure_early_kill",
         .data       = &sysctl_memory_failure_early_kill,
         .maxlen     = sizeof(sysctl_memory_failure_early_kill),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
     {
         .procname   = "memory_failure_recovery",
         .data       = &sysctl_memory_failure_recovery,
         .maxlen     = sizeof(sysctl_memory_failure_recovery),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
 #endif
     {
         .procname   = "user_reserve_kbytes",
         .data       = &sysctl_user_reserve_kbytes,
         .maxlen     = sizeof(sysctl_user_reserve_kbytes),
         .mode       = 0644,
         .proc_handler   = proc_doulongvec_minmax,
     },
     {
         .procname   = "admin_reserve_kbytes",
         .data       = &sysctl_admin_reserve_kbytes,
         .maxlen     = sizeof(sysctl_admin_reserve_kbytes),
         .mode       = 0644,
         .proc_handler   = proc_doulongvec_minmax,
     },
 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
     {
         .procname   = "mmap_rnd_bits",
         .data       = &mmap_rnd_bits,
         .maxlen     = sizeof(mmap_rnd_bits),
         .mode       = 0600,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = (void *)&mmap_rnd_bits_min,
         .extra2     = (void *)&mmap_rnd_bits_max,
     },
 #endif
 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
     {
         .procname   = "mmap_rnd_compat_bits",
         .data       = &mmap_rnd_compat_bits,
         .maxlen     = sizeof(mmap_rnd_compat_bits),
         .mode       = 0600,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = (void *)&mmap_rnd_compat_bits_min,
         .extra2     = (void *)&mmap_rnd_compat_bits_max,
     },
 #endif
 #ifdef CONFIG_USERFAULTFD
     {
         .procname   = "unprivileged_userfaultfd",
         .data       = &sysctl_unprivileged_userfaultfd,
         .maxlen     = sizeof(sysctl_unprivileged_userfaultfd),
         .mode       = 0644,
         .proc_handler   = proc_dointvec_minmax,
         .extra1     = SYSCTL_ZERO,
         .extra2     = SYSCTL_ONE,
     },
 #endif
     { }
 };
 
 static struct ctl_table debug_table[] = {
 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
     {
         .procname   = "exception-trace",
         .data       = &show_unhandled_signals,
         .maxlen     = sizeof(int),
         .mode       = 0644,
         .proc_handler   = proc_dointvec
     },
 #endif
     { }
 };
 
 static struct ctl_table dev_table[] = {
     { }
 };
 
 DECLARE_SYSCTL_BASE(kernel, kern_table);
 DECLARE_SYSCTL_BASE(vm, vm_table);
 DECLARE_SYSCTL_BASE(debug, debug_table);
 DECLARE_SYSCTL_BASE(dev, dev_table);
 
 int __init sysctl_init_bases(void)
 {
     register_sysctl_base(kernel);
     register_sysctl_base(vm);
     register_sysctl_base(debug);
     register_sysctl_base(dev);
 
     return 0;
 }
 #endif /* CONFIG_SYSCTL */
 /*
  * No sense putting this after each symbol definition, twice,
  * exception granted :-)
  */
 EXPORT_SYMBOL(proc_dobool);
 EXPORT_SYMBOL(proc_dointvec);
 EXPORT_SYMBOL(proc_douintvec);
 EXPORT_SYMBOL(proc_dointvec_jiffies);
 EXPORT_SYMBOL(proc_dointvec_minmax);
 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
 EXPORT_SYMBOL(proc_dostring);
 EXPORT_SYMBOL(proc_doulongvec_minmax);
 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
 EXPORT_SYMBOL(proc_do_large_bitmap);

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