diff options
| -rw-r--r-- | fs/proc/proc_sysctl.c | 6 | ||||
| -rw-r--r-- | include/linux/sysctl.h | 2 | ||||
| -rw-r--r-- | kernel/sysctl.c | 65 |
3 files changed, 73 insertions, 0 deletions
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 984e42f8cb11..7256b8962e3c 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -1108,6 +1108,11 @@ static int sysctl_check_table_array(const char *path, struct ctl_table *table) err |= sysctl_err(path, table, "array not allowed"); } + if (table->proc_handler == proc_dou8vec_minmax) { + if (table->maxlen != sizeof(u8)) + err |= sysctl_err(path, table, "array not allowed"); + } + return err; } @@ -1123,6 +1128,7 @@ static int sysctl_check_table(const char *path, struct ctl_table *table) (table->proc_handler == proc_douintvec) || (table->proc_handler == proc_douintvec_minmax) || (table->proc_handler == proc_dointvec_minmax) || + (table->proc_handler == proc_dou8vec_minmax) || (table->proc_handler == proc_dointvec_jiffies) || (table->proc_handler == proc_dointvec_userhz_jiffies) || (table->proc_handler == proc_dointvec_ms_jiffies) || diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 51298a4f4623..d99ca99837de 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -53,6 +53,8 @@ int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_douintvec_minmax(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos); +int proc_dou8vec_minmax(struct ctl_table *table, int write, void *buffer, + size_t *lenp, loff_t *ppos); int proc_dointvec_jiffies(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_dointvec_userhz_jiffies(struct ctl_table *, int, void *, size_t *, loff_t *); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 62fbd09b5dc1..90d2892ef6a3 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1034,6 +1034,65 @@ int proc_douintvec_minmax(struct ctl_table *table, int write, do_proc_douintvec_minmax_conv, ¶m); } +/** + * 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 = *data; + res = do_proc_douintvec(&tmp, write, buffer, lenp, ppos, + do_proc_douintvec_minmax_conv, ¶m); + if (res) + return res; + if (write) + *data = val; + return 0; +} +EXPORT_SYMBOL_GPL(proc_dou8vec_minmax); + static int do_proc_dopipe_max_size_conv(unsigned long *lvalp, unsigned int *valp, int write, void *data) @@ -1582,6 +1641,12 @@ int proc_douintvec_minmax(struct ctl_table *table, int write, 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) { |