From c381d02b2fd5f82d2207db1b9b25ff60d0d9c27c Mon Sep 17 00:00:00 2001 From: Yuwei Wang Date: Wed, 29 Jun 2022 08:48:31 +0000 Subject: [PATCH] sysctl: add proc_dointvec_ms_jiffies_minmax add proc_dointvec_ms_jiffies_minmax to fit read msecs value to jiffies with a limited range of values Signed-off-by: Yuwei Wang Signed-off-by: Paolo Abeni --- include/linux/sysctl.h | 2 ++ kernel/sysctl.c | 41 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+) diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 80263f7..17b42ce 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -75,6 +75,8 @@ int proc_douintvec_minmax(struct ctl_table *table, int write, void *buffer, 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_ms_jiffies_minmax(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos); int proc_dointvec_userhz_jiffies(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_dointvec_ms_jiffies(struct ctl_table *, int, void *, size_t *, diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e52b6e3..85c92e2 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1237,6 +1237,30 @@ static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp, 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 @@ -1259,6 +1283,17 @@ int proc_dointvec_jiffies(struct ctl_table *table, int write, 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, ¶m); +} + /** * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds * @table: the sysctl table @@ -1523,6 +1558,12 @@ int proc_dointvec_jiffies(struct ctl_table *table, int write, 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) { -- 2.7.4