On Thu, May 04, 2017 at 12:13:38PM -0400, Mathias Rav wrote:
> Prefer kstrtouint_from_user to copy_from_user+simple_strtoul.
>
> The helper function lprocfs_wr_uint() is only used to implement
> "dump_granted_max" in debugfs.
>
> Note the slight change in semantics: The previous implementation using
> simple_strtoul allows garbage after the number, whereas kstrtox only allows
> a trailing line break. The previous implementation allowed a write of zero
> bytes whereas kstrtox will return -EINVAL. Since this only affects a single
> debugfs endpoint, this should be a permissible slight change of semantics
> in exchange for 18 fewer lines of code.
>
> Signed-off-by: Mathias Rav <mathiasrav@xxxxxxxxx>
> ---
> .../lustre/lustre/obdclass/lprocfs_status.c | 22 +---------------------
> 1 file changed, 1 insertion(+), 21 deletions(-)
>
> diff --git a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
> index 1ec6e3767d81..338ce34d6514 100644
> --- a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
> +++ b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
> @@ -399,27 +399,7 @@ EXPORT_SYMBOL(lprocfs_rd_uint);
> int lprocfs_wr_uint(struct file *file, const char __user *buffer,
> unsigned long count, void *data)
> {
> - unsigned *p = data;
> - char dummy[MAX_STRING_SIZE + 1], *end;
> - unsigned long tmp;
> -
> - if (count >= sizeof(dummy))
> - return -EINVAL;
> -
> - if (count == 0)
> - return 0;
> -
> - if (copy_from_user(dummy, buffer, count))
> - return -EFAULT;
> -
> - dummy[count] = '\0';
> -
> - tmp = simple_strtoul(dummy, &end, 0);
> - if (dummy == end)
> - return -EINVAL;
> -
> - *p = (unsigned int)tmp;
> - return count;
> + return kstrtouint_from_user(buffer, count, 0, (unsigned int *)data);
Why not just delete this whole function and have the callers make this
call instead? No need for unneeded wrapper functions of core kernel
calls.
thanks,
greg k-h
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
