diff options
Diffstat (limited to 'kernel/sysctl.c')
| -rw-r--r-- | kernel/sysctl.c | 3057 |
1 files changed, 1479 insertions, 1578 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index b9ff323e1d26..7efe0d499c1d 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -68,6 +68,9 @@ #include <linux/bpf.h> #include <linux/mount.h> #include <linux/userfaultfd_k.h> +#include <linux/coredump.h> +#include <linux/latencytop.h> +#include <linux/pid.h> #include "../lib/kstrtox.h" @@ -103,22 +106,6 @@ #if defined(CONFIG_SYSCTL) -/* External variables not in a header file. */ -extern int suid_dumpable; -#ifdef CONFIG_COREDUMP -extern int core_uses_pid; -extern char core_pattern[]; -extern unsigned int core_pipe_limit; -#endif -extern int pid_max; -extern int pid_max_min, pid_max_max; -extern int percpu_pagelist_fraction; -extern int latencytop_enabled; -extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max; -#ifndef CONFIG_MMU -extern int sysctl_nr_trim_pages; -#endif - /* Constants used for minimum and maximum */ #ifdef CONFIG_LOCKUP_DETECTOR static int sixty = 60; @@ -160,24 +147,6 @@ static unsigned long hung_task_timeout_max = (LONG_MAX/HZ); #ifdef CONFIG_INOTIFY_USER #include <linux/inotify.h> #endif -#ifdef CONFIG_SPARC -#endif - -#ifdef CONFIG_PARISC -extern int pwrsw_enabled; -#endif - -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW -extern int unaligned_enabled; -#endif - -#ifdef CONFIG_IA64 -extern int unaligned_dump_stack; -#endif - -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN -extern int no_unaligned_warning; -#endif #ifdef CONFIG_PROC_SYSCTL @@ -207,102 +176,1472 @@ enum sysctl_writes_mode { }; 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_SCHED_DEBUG +static int min_sched_granularity_ns = 100000; /* 100 usecs */ +static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ +static int min_wakeup_granularity_ns; /* 0 usecs */ +static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ +#ifdef CONFIG_SMP +static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE; +static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1; +#endif /* CONFIG_SMP */ +#endif /* CONFIG_SCHED_DEBUG */ -static int proc_do_cad_pid(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -static int proc_taint(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); #ifdef CONFIG_COMPACTION -static int proc_dointvec_minmax_warn_RT_change(struct ctl_table *table, - int write, void __user *buffer, - size_t *lenp, loff_t *ppos); +static int min_extfrag_threshold; +static int max_extfrag_threshold = 1000; +#endif + +#endif /* CONFIG_SYSCTL */ + +#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_SYSCTL) +static int bpf_stats_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + struct static_key *key = (struct static_key *)table->data; + static int saved_val; + 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(&bpf_stats_enabled_mutex); + val = saved_val; + ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); + if (write && !ret && val != saved_val) { + if (val) + static_key_slow_inc(key); + else + static_key_slow_dec(key); + saved_val = val; + } + mutex_unlock(&bpf_stats_enabled_mutex); + return ret; +} #endif + +/* + * /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_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; + *valp = -*lvalp; + } else { + if (*lvalp > (unsigned long) INT_MAX) + return -EINVAL; + *valp = *lvalp; + } + } else { + int val = *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; + *valp = *lvalp; + } else { + unsigned int val = *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); +} + +static 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_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) { + /* + * Poor man's atomic or. Not worth adding a primitive + * to everyone's atomic.h for this + */ + int i; + for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) { + if ((tmptaint >> i) & 1) + add_taint(i, LOCKDEP_STILL_OK); + } + } + + return err; +} + #ifdef CONFIG_PRINTK static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); + void *buffer, size_t *lenp, loff_t *ppos) +{ + if (write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + return proc_dointvec_minmax(table, write, buffer, lenp, ppos); +} +#endif + +/** + * 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; + *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, ¶m); +} + +/** + * 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; + + *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, ¶m); +} + +static int do_proc_dopipe_max_size_conv(unsigned long *lvalp, + unsigned int *valp, + int write, void *data) +{ + if (write) { + unsigned int val; + + val = round_pipe_size(*lvalp); + if (val == 0) + return -EINVAL; + + *valp = val; + } else { + unsigned int val = *valp; + *lvalp = (unsigned long) val; + } + + return 0; +} + +static int proc_dopipe_max_size(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_dopipe_max_size_conv, NULL); +} + +static void validate_coredump_safety(void) +{ +#ifdef CONFIG_COREDUMP + if (suid_dumpable == SUID_DUMP_ROOT && + core_pattern[0] != '/' && core_pattern[0] != '|') { + printk(KERN_WARNING +"Unsafe core_pattern used with fs.suid_dumpable=2.\n" +"Pipe handler or fully qualified core dump path required.\n" +"Set kernel.core_pattern before fs.suid_dumpable.\n" + ); + } #endif +} static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); + void *buffer, size_t *lenp, loff_t *ppos) +{ + int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + if (!error) + validate_coredump_safety(); + return error; +} + #ifdef CONFIG_COREDUMP static int proc_dostring_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); + void *buffer, size_t *lenp, loff_t *ppos) +{ + int error = proc_dostring(table, write, buffer, lenp, ppos); + if (!error) + validate_coredump_safety(); + return error; +} #endif -static int proc_dopipe_max_size(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); #ifdef CONFIG_MAGIC_SYSRQ static int sysrq_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos); -#endif + void *buffer, size_t *lenp, loff_t *ppos) +{ + int tmp, ret; -static struct ctl_table kern_table[]; -static struct ctl_table vm_table[]; -static struct ctl_table fs_table[]; -static struct ctl_table debug_table[]; -static struct ctl_table dev_table[]; -extern struct ctl_table random_table[]; -#ifdef CONFIG_EPOLL -extern struct ctl_table epoll_table[]; -#endif + tmp = sysrq_mask(); -#ifdef CONFIG_FW_LOADER_USER_HELPER -extern struct ctl_table firmware_config_table[]; -#endif + ret = __do_proc_dointvec(&tmp, table, write, buffer, + lenp, ppos, NULL, NULL); + if (ret || !write) + return ret; -#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \ - defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT) -int sysctl_legacy_va_layout; + if (write) + sysrq_toggle_support(tmp); + + return 0; +} #endif -/* The default sysctl tables: */ +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; -static struct ctl_table sysctl_base_table[] = { - { - .procname = "kernel", - .mode = 0555, - .child = kern_table, - }, - { - .procname = "vm", - .mode = 0555, - .child = vm_table, - }, - { - .procname = "fs", - .mode = 0555, - .child = fs_table, - }, - { - .procname = "debug", - .mode = 0555, - .child = debug_table, - }, - { - .procname = "dev", - .mode = 0555, - .child = dev_table, - }, - { } -}; + if (!data || !table->maxlen || !*lenp || (*ppos && !write)) { + *lenp = 0; + return 0; + } -#ifdef CONFIG_SCHED_DEBUG -static int min_sched_granularity_ns = 100000; /* 100 usecs */ -static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ -static int min_wakeup_granularity_ns; /* 0 usecs */ -static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ -#ifdef CONFIG_SMP -static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE; -static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1; -#endif /* CONFIG_SMP */ -#endif /* CONFIG_SCHED_DEBUG */ + i = (unsigned long *) data; + min = (unsigned long *) table->extra1; + max = (unsigned long *) table->extra2; + vleft = table->maxlen / sizeof(unsigned long); + left = *lenp; -#ifdef CONFIG_COMPACTION -static int min_extfrag_threshold; -static int max_extfrag_threshold = 1000; -#endif + 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) + break; + if (neg) + continue; + val = convmul * val / convdiv; + if ((min && val < *min) || (max && val > *max)) { + err = -EINVAL; + break; + } + *i = val; + } else { + val = convdiv * (*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; + *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); + } else { + int val = *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; + *valp = (int)jif; + } 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_msecs(lval); + } + 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); +} + +/** + * 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; + bool first = 1; + 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); + first = 0; + proc_skip_char(&p, &left, '\n'); + } + left += skipped; + } else { + unsigned long bit_a, bit_b = 0; + + 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_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_dointvec_jiffies(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[] = { { @@ -613,7 +1952,7 @@ static struct ctl_table kern_table[] = { .procname = "soft-power", .data = &pwrsw_enabled, .maxlen = sizeof (int), - .mode = 0644, + .mode = 0644, .proc_handler = proc_dointvec, }, #endif @@ -1074,7 +2413,7 @@ static struct ctl_table kern_table[] = { .procname = "ignore-unaligned-usertrap", .data = &no_unaligned_warning, .maxlen = sizeof (int), - .mode = 0644, + .mode = 0644, .proc_handler = proc_dointvec, }, #endif @@ -1246,7 +2585,7 @@ static struct ctl_table kern_table[] = { .data = &bpf_stats_enabled_key.key, .maxlen = sizeof(bpf_stats_enabled_key), .mode = 0644, - .proc_handler = proc_do_static_key, + .proc_handler = bpf_stats_handler, }, #endif #if defined(CONFIG_TREE_RCU) @@ -1322,7 +2661,7 @@ static struct ctl_table vm_table[] = { .proc_handler = overcommit_kbytes_handler, }, { - .procname = "page-cluster", + .procname = "page-cluster", .data = &page_cluster, .maxlen = sizeof(int), .mode = 0644, @@ -1493,7 +2832,7 @@ static struct ctl_table vm_table[] = { .data = &watermark_boost_factor, .maxlen = sizeof(watermark_boost_factor), .mode = 0644, - .proc_handler = watermark_boost_factor_sysctl_handler, + .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, }, { @@ -1961,6 +3300,35 @@ static struct ctl_table dev_table[] = { { } }; +static struct ctl_table sysctl_base_table[] = { + { + .procname = "kernel", + .mode = 0555, + .child = kern_table, + }, + { + .procname = "vm", + .mode = 0555, + .child = vm_table, + }, + { + .procname = "fs", + .mode = 0555, + .child = fs_table, + }, + { + .procname = "debug", + .mode = 0555, + .child = debug_table, + }, + { + .procname = "dev", + .mode = 0555, + .child = dev_table, + }, + { } +}; + int __init sysctl_init(void) { struct ctl_table_header *hdr; @@ -1969,1474 +3337,7 @@ int __init sysctl_init(void) kmemleak_not_leak(hdr); return 0; } - #endif /* CONFIG_SYSCTL */ - -/* - * /proc/sys support - */ - -#ifdef CONFIG_PROC_SYSCTL - -static int _proc_do_string(char *data, int maxlen, int write, - char __user *buffer, - size_t *lenp, loff_t *ppos) -{ - size_t len; - char __user *p; - char c; - - 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) { - if (get_user(c, p++)) - return -EFAULT; - 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) - if (copy_to_user(buffer, data, len)) - return -EFAULT; - if (len < *lenp) { - if (put_user('\n', buffer + len)) - return -EFAULT; - 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 __user *buffer, size_t *lenp, loff_t *ppos) -{ - if (write) - proc_first_pos_non_zero_ignore(ppos, table); - - return _proc_do_string((char *)(table->data), table->maxlen, write, - (char __user *)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 %0 is returned and @buf and @size are updated with - * the amount of bytes written. - */ -static int proc_put_long(void __user **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; - if (copy_to_user(*buf, tmp, len)) - return -EFAULT; - *size -= len; - *buf += len; - return 0; -} -#undef TMPBUFLEN - -static int proc_put_char(void __user **buf, size_t *size, char c) -{ - if (*size) { - char __user **buffer = (char __user **)buf; - if (put_user(c, *buffer)) - return -EFAULT; - (*size)--, (*buffer)++; - *buf = *buffer; - } - 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; - *valp = -*lvalp; - } else { - if (*lvalp > (unsigned long) INT_MAX) - return -EINVAL; - *valp = *lvalp; - } - } else { - int val = *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; - *valp = *lvalp; - } else { - unsigned int val = *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 __user *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 *kbuf = NULL, *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 = kbuf = memdup_user_nul(buffer, left); - if (IS_ERR(kbuf)) - return PTR_ERR(kbuf); - } - - 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) - err = proc_put_char(&buffer, &left, '\t'); - if (err) - break; - err = proc_put_long(&buffer, &left, lval, neg); - if (err) - break; - } - } - - if (!write && !first && left && !err) - err = proc_put_char(&buffer, &left, '\n'); - if (write && !err && left) - left -= proc_skip_spaces(&p); - if (write) { - kfree(kbuf); - if (first) - return err ? : -EINVAL; - } - *lenp -= left; -out: - *ppos += *lenp; - return err; -} - -static int do_proc_dointvec(struct ctl_table *table, int write, - void __user *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 __user *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 *kbuf = NULL, *p; - - left = *lenp; - - if (proc_first_pos_non_zero_ignore(ppos, table)) - goto bail_early; - - if (left > PAGE_SIZE - 1) - left = PAGE_SIZE - 1; - - p = kbuf = memdup_user_nul(buffer, left); - if (IS_ERR(kbuf)) - return -EINVAL; - - 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: - kfree(kbuf); - 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 __user *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; - } - - err = proc_put_long(&buffer, &left, lval, false); - if (err || !left) - goto out; - - err = 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 __user *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); -} - -static int do_proc_douintvec(struct ctl_table *table, int write, - void __user *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_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 __user *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 __user *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 __user *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 __user *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) { - /* - * Poor man's atomic or. Not worth adding a primitive - * to everyone's atomic.h for this - */ - int i; - for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) { - if ((tmptaint >> i) & 1) - add_taint(i, LOCKDEP_STILL_OK); - } - } - - return err; -} - -#ifdef CONFIG_PRINTK -static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - if (write && !capable(CAP_SYS_ADMIN)) - return -EPERM; - - return proc_dointvec_minmax(table, write, buffer, lenp, ppos); -} -#endif - -/** - * 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; - *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 __user *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, ¶m); -} - -/** - * 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; - - *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 __user *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, ¶m); -} - -static int do_proc_dopipe_max_size_conv(unsigned long *lvalp, - unsigned int *valp, - int write, void *data) -{ - if (write) { - unsigned int val; - - val = round_pipe_size(*lvalp); - if (val == 0) - return -EINVAL; - - *valp = val; - } else { - unsigned int val = *valp; - *lvalp = (unsigned long) val; - } - - return 0; -} - -static int proc_dopipe_max_size(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return do_proc_douintvec(table, write, buffer, lenp, ppos, - do_proc_dopipe_max_size_conv, NULL); -} - -static void validate_coredump_safety(void) -{ -#ifdef CONFIG_COREDUMP - if (suid_dumpable == SUID_DUMP_ROOT && - core_pattern[0] != '/' && core_pattern[0] != '|') { - printk(KERN_WARNING -"Unsafe core_pattern used with fs.suid_dumpable=2.\n" -"Pipe handler or fully qualified core dump path required.\n" -"Set kernel.core_pattern before fs.suid_dumpable.\n" - ); - } -#endif -} - -static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos); - if (!error) - validate_coredump_safety(); - return error; -} - -#ifdef CONFIG_COREDUMP -static int proc_dostring_coredump(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - int error = proc_dostring(table, write, buffer, lenp, ppos); - if (!error) - validate_coredump_safety(); - return error; -} -#endif - -#ifdef CONFIG_MAGIC_SYSRQ -static int sysrq_sysctl_handler(struct ctl_table *table, int write, - void __user *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 __user *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 *kbuf = NULL, *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 = kbuf = memdup_user_nul(buffer, left); - if (IS_ERR(kbuf)) - return PTR_ERR(kbuf); - } - - 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) - break; - if (neg) - continue; - val = convmul * val / convdiv; - if ((min && val < *min) || (max && val > *max)) { - err = -EINVAL; - break; - } - *i = val; - } else { - val = convdiv * (*i) / convmul; - if (!first) { - err = proc_put_char(&buffer, &left, '\t'); - if (err) - break; - } - err = proc_put_long(&buffer, &left, val, false); - if (err) - break; - } - } - - if (!write && !first && left && !err) - err = proc_put_char(&buffer, &left, '\n'); - if (write && !err) - left -= proc_skip_spaces(&p); - if (write) { - kfree(kbuf); - if (first) - return err ? : -EINVAL; - } - *lenp -= left; -out: - *ppos += *lenp; - return err; -} - -static int do_proc_doulongvec_minmax(struct ctl_table *table, int write, - void __user *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 __user *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 __user *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; - *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); - } else { - int val = *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; - *valp = (int)jif; - } 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_msecs(lval); - } - 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 __user *buffer, size_t *lenp, loff_t *ppos) -{ - return do_proc_dointvec(table,write,buffer,lenp,ppos, - do_proc_dointvec_jiffies_conv,NULL); -} - -/** - * 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 __user *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 __user *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 __user *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 __user *buffer, size_t *lenp, loff_t *ppos) -{ - int err = 0; - bool first = 1; - 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 *kbuf, *p; - 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; - } - - p = kbuf = memdup_user_nul(buffer, left); - if (IS_ERR(kbuf)) - return PTR_ERR(kbuf); - - tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL); - if (!tmp_bitmap) { - kfree(kbuf); - 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); - first = 0; - proc_skip_char(&p, &left, '\n'); - } - kfree(kbuf); - left += skipped; - } else { - unsigned long bit_a, bit_b = 0; - - 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) { - err = proc_put_char(&buffer, &left, ','); - if (err) - break; - } - err = proc_put_long(&buffer, &left, bit_a, false); - if (err) - break; - if (bit_a != bit_b) { - err = proc_put_char(&buffer, &left, '-'); - if (err) - break; - err = proc_put_long(&buffer, &left, bit_b, false); - if (err) - break; - } - - first = 0; bit_b++; - } - if (!err) - err = 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 __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_douintvec(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_douintvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_doulongvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_do_large_bitmap(struct ctl_table *table, int write, - void __user *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 __user *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; -} -#endif /* * No sense putting this after each symbol definition, twice, * exception granted :-) |