linux-stable/kernel/sysctl.c
Linus Torvalds 6a8cbd9253 v6.5-rc1-sysctl-next
The changes queued up for v6.5-rc1 for sysctl are in line with
 prior efforts to stop usage of deprecated routines which incur
 recursion and also make it hard to remove the empty array element
 in each sysctl array declaration. The most difficult user to modify
 was parport which required a bit of re-thinking of how to declare shared
 sysctls there, Joel Granados has stepped up to the plate to do most of
 this work and eventual removal of register_sysctl_table(). That work
 ended up saving us about 1465 bytes according to bloat-o-meter. Since
 we gained a few bloat-o-meter karma points I moved two rather small
 sysctl arrays from kernel/sysctl.c leaving us only two more sysctl
 arrays to move left.
 
 Most changes have been tested on linux-next for about a month. The last
 straggler patches are a minor parport fix, changes to the sysctl
 kernel selftest so to verify correctness and prevent regressions for
 the future change he made to provide an alternative solution for the
 special sysctl mount point target which was using the now deprecated
 sysctl child element.
 
 This is all prep work to now finally be able to remove the empty
 array element in all sysctl declarations / registrations which is
 expected to save us a bit of bytes all over the kernel. That work
 will be tested early after v6.5-rc1 is out.
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Merge tag 'v6.5-rc1-sysctl-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull sysctl updates from Luis Chamberlain:
 "The changes for sysctl are in line with prior efforts to stop usage of
  deprecated routines which incur recursion and also make it hard to
  remove the empty array element in each sysctl array declaration.

  The most difficult user to modify was parport which required a bit of
  re-thinking of how to declare shared sysctls there, Joel Granados has
  stepped up to the plate to do most of this work and eventual removal
  of register_sysctl_table(). That work ended up saving us about 1465
  bytes according to bloat-o-meter. Since we gained a few bloat-o-meter
  karma points I moved two rather small sysctl arrays from
  kernel/sysctl.c leaving us only two more sysctl arrays to move left.

  Most changes have been tested on linux-next for about a month. The
  last straggler patches are a minor parport fix, changes to the sysctl
  kernel selftest so to verify correctness and prevent regressions for
  the future change he made to provide an alternative solution for the
  special sysctl mount point target which was using the now deprecated
  sysctl child element.

  This is all prep work to now finally be able to remove the empty array
  element in all sysctl declarations / registrations which is expected
  to save us a bit of bytes all over the kernel. That work will be
  tested early after v6.5-rc1 is out"

* tag 'v6.5-rc1-sysctl-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  sysctl: replace child with an enumeration
  sysctl: Remove debugging dump_stack
  test_sysclt: Test for registering a mount point
  test_sysctl: Add an option to prevent test skip
  test_sysctl: Add an unregister sysctl test
  test_sysctl: Group node sysctl test under one func
  test_sysctl: Fix test metadata getters
  parport: plug a sysctl register leak
  sysctl: move security keys sysctl registration to its own file
  sysctl: move umh sysctl registration to its own file
  signal: move show_unhandled_signals sysctl to its own file
  sysctl: remove empty dev table
  sysctl: Remove register_sysctl_table
  sysctl: Refactor base paths registrations
  sysctl: stop exporting register_sysctl_table
  parport: Removed sysctl related defines
  parport: Remove register_sysctl_table from parport_default_proc_register
  parport: Remove register_sysctl_table from parport_device_proc_register
  parport: Remove register_sysctl_table from parport_proc_register
  parport: Move magic number "15" to a define
2023-06-28 16:05:21 -07:00

2278 lines
54 KiB
C

// 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/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
/* shared constants to be used in various sysctls */
const int sysctl_vals[] = { 0, 1, 2, 3, 4, 100, 200, 1000, 3000, INT_MAX, 65535, -1 };
EXPORT_SYMBOL(sysctl_vals);
const unsigned long sysctl_long_vals[] = { 0, 1, LONG_MAX };
EXPORT_SYMBOL_GPL(sysctl_long_vals);
#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
#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 void proc_skip_spaces(char **buf, size_t *size)
{
while (*size) {
if (!isspace(**buf))
break;
(*size)--;
(*buf)++;
}
}
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)
{
char *p, tmp[TMPBUFLEN];
ssize_t len = *size;
if (len <= 0)
return -EINVAL;
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_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) {
proc_skip_spaces(&p, &left);
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)
proc_skip_spaces(&p, &left);
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;
proc_skip_spaces(&p, &left);
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)
proc_skip_spaces(&p, &left);
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 one integer value from/to the user buffer,
* treated as an ASCII string.
*
* table->data must point to a bool variable and table->maxlen must
* be sizeof(bool).
*
* Returns 0 on success.
*/
int proc_dobool(struct ctl_table *table, int write, void *buffer,
size_t *lenp, loff_t *ppos)
{
struct ctl_table tmp;
bool *data = table->data;
int res, val;
/* Do not support arrays yet. */
if (table->maxlen != sizeof(bool))
return -EINVAL;
tmp = *table;
tmp.maxlen = sizeof(val);
tmp.data = &val;
val = READ_ONCE(*data);
res = proc_dointvec(&tmp, write, buffer, lenp, ppos);
if (res)
return res;
if (write)
WRITE_ONCE(*data, val);
return 0;
}
/**
* 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);
}
/**
* 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 = data;
min = table->extra1;
max = 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;
proc_skip_spaces(&p, &left);
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)
proc_skip_spaces(&p, &left);
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[] = {
{
.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 = "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_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,
.extra2 = (void *)&page_cluster_max,
},
{
.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
{
.procname = "drop_caches",
.data = &sysctl_drop_caches,
.maxlen = sizeof(int),
.mode = 0200,
.proc_handler = drop_caches_sysctl_handler,
.extra1 = SYSCTL_ONE,
.extra2 = SYSCTL_FOUR,
},
{
.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,
},
#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
#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
{
.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
{ }
};
int __init sysctl_init_bases(void)
{
register_sysctl_init("kernel", kern_table);
register_sysctl_init("vm", vm_table);
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);