Re: [PATCH] cachefiles: convert deprecated simple_strtoul() to kstrtoul() in percentage command handlers

[DRIF ABDELMALEK MOHAMED SAID]

Gentle ping on this one — seems to have gotten buried during the merge window.

Thanks,


On Sat, Aug 29, 2026 at 11:45 PM Drif Abdelmalek Mohamed Said
<drifabdelmalekmohamedsaid@xxxxxxxxx> wrote:
>
> Convert the six <N>% percentage command handlers -
> cachefiles_daemon_frun(), _fcull(), _fstop(), _brun(), _bcull(), and
> _bstop() - from the deprecated simple_strtoul() to kstrtoul(). These
> are the only handlers in this file that take a trailing '%' after
> the number; other nearby commands take plain values and are
> unaffected.
>
> Since kstrtoul() requires the whole input to be a valid number, each
> handler now walks the digit run itself, checks it's followed by '%'
> and NUL, and temporarily null-terminates at the '%' to isolate the
> number for kstrtoul(), restoring it afterwards.
>
> Signed-off-by: Drif Abdelmalek Mohamed Said <drifabdelmalekmohamedsaid@xxxxxxxxx>
> ---
>  fs/cachefiles/daemon.c | 78 +++++++++++++++++++++++++++++++++++-------
>  1 file changed, 66 insertions(+), 12 deletions(-)
>
> diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c
> index 1a66e0af2837..12c38b366881 100644
> --- a/fs/cachefiles/daemon.c
> +++ b/fs/cachefiles/daemon.c
> @@ -331,16 +331,25 @@ static int cachefiles_daemon_range_error(struct cachefiles_cache *cache,
>  static int cachefiles_daemon_frun(struct cachefiles_cache *cache, char *args)
>  {
>         unsigned long frun;
> +       char *end = args;
> +       int ret;
>
>         _enter(",%s", args);
>
>         if (!*args)
>                 return -EINVAL;
>
> -       frun = simple_strtoul(args, &args, 10);
> -       if (args[0] != '%' || args[1] != '\0')
> +       while (isdigit(*end))
> +               end++;
> +       if (end == args || *end != '%' || end[1] != '\0')
>                 return -EINVAL;
>
> +       *end = '\0';
> +       ret = kstrtoul(args, 10, &frun);
> +       *end = '%';
> +       if (ret)
> +               return ret;
> +
>         if (frun <= cache->fcull_percent || frun >= 100)
>                 return cachefiles_daemon_range_error(cache, args);
>
> @@ -355,16 +364,25 @@ static int cachefiles_daemon_frun(struct cachefiles_cache *cache, char *args)
>  static int cachefiles_daemon_fcull(struct cachefiles_cache *cache, char *args)
>  {
>         unsigned long fcull;
> +       char *end = args;
> +       int ret;
>
>         _enter(",%s", args);
>
>         if (!*args)
>                 return -EINVAL;
>
> -       fcull = simple_strtoul(args, &args, 10);
> -       if (args[0] != '%' || args[1] != '\0')
> +       while (isdigit(*end))
> +               end++;
> +       if (end == args || *end != '%' || end[1] != '\0')
>                 return -EINVAL;
>
> +       *end = '\0';
> +       ret = kstrtoul(args, 10, &fcull);
> +       *end = '%';
> +       if (ret)
> +               return ret;
> +
>         if (fcull <= cache->fstop_percent || fcull >= cache->frun_percent)
>                 return cachefiles_daemon_range_error(cache, args);
>
> @@ -379,16 +397,25 @@ static int cachefiles_daemon_fcull(struct cachefiles_cache *cache, char *args)
>  static int cachefiles_daemon_fstop(struct cachefiles_cache *cache, char *args)
>  {
>         unsigned long fstop;
> +       char *end = args;
> +       int ret;
>
>         _enter(",%s", args);
>
>         if (!*args)
>                 return -EINVAL;
>
> -       fstop = simple_strtoul(args, &args, 10);
> -       if (args[0] != '%' || args[1] != '\0')
> +       while (isdigit(*end))
> +               end++;
> +       if (end == args || *end != '%' || end[1] != '\0')
>                 return -EINVAL;
>
> +       *end = '\0';
> +       ret = kstrtoul(args, 10, &fstop);
> +       *end = '%';
> +       if (ret)
> +               return ret;
> +
>         if (fstop >= cache->fcull_percent)
>                 return cachefiles_daemon_range_error(cache, args);
>
> @@ -403,16 +430,25 @@ static int cachefiles_daemon_fstop(struct cachefiles_cache *cache, char *args)
>  static int cachefiles_daemon_brun(struct cachefiles_cache *cache, char *args)
>  {
>         unsigned long brun;
> +       char *end = args;
> +       int ret;
>
>         _enter(",%s", args);
>
>         if (!*args)
>                 return -EINVAL;
>
> -       brun = simple_strtoul(args, &args, 10);
> -       if (args[0] != '%' || args[1] != '\0')
> +       while (isdigit(*end))
> +               end++;
> +       if (end == args || *end != '%' || end[1] != '\0')
>                 return -EINVAL;
>
> +       *end = '\0';
> +       ret = kstrtoul(args, 10, &brun);
> +       *end = '%';
> +       if (ret)
> +               return ret;
> +
>         if (brun <= cache->bcull_percent || brun >= 100)
>                 return cachefiles_daemon_range_error(cache, args);
>
> @@ -427,16 +463,25 @@ static int cachefiles_daemon_brun(struct cachefiles_cache *cache, char *args)
>  static int cachefiles_daemon_bcull(struct cachefiles_cache *cache, char *args)
>  {
>         unsigned long bcull;
> +       char *end = args;
> +       int ret;
>
>         _enter(",%s", args);
>
>         if (!*args)
>                 return -EINVAL;
>
> -       bcull = simple_strtoul(args, &args, 10);
> -       if (args[0] != '%' || args[1] != '\0')
> +       while (isdigit(*end))
> +               end++;
> +       if (end == args || *end != '%' || end[1] != '\0')
>                 return -EINVAL;
>
> +       *end = '\0';
> +       ret = kstrtoul(args, 10, &bcull);
> +       *end = '%';
> +       if (ret)
> +               return ret;
> +
>         if (bcull <= cache->bstop_percent || bcull >= cache->brun_percent)
>                 return cachefiles_daemon_range_error(cache, args);
>
> @@ -451,16 +496,25 @@ static int cachefiles_daemon_bcull(struct cachefiles_cache *cache, char *args)
>  static int cachefiles_daemon_bstop(struct cachefiles_cache *cache, char *args)
>  {
>         unsigned long bstop;
> +       char *end = args;
> +       int ret;
>
>         _enter(",%s", args);
>
>         if (!*args)
>                 return -EINVAL;
>
> -       bstop = simple_strtoul(args, &args, 10);
> -       if (args[0] != '%' || args[1] != '\0')
> +       while (isdigit(*end))
> +               end++;
> +       if (end == args || *end != '%' || end[1] != '\0')
>                 return -EINVAL;
>
> +       *end = '\0';
> +       ret = kstrtoul(args, 10, &bstop);
> +       *end = '%';
> +       if (ret)
> +               return ret;
> +
>         if (bstop >= cache->bcull_percent)
>                 return cachefiles_daemon_range_error(cache, args);
>
> --
> 2.43.0
>