On Thu, Oct 21, 2021 at 01:44:56PM +0200, Lukas Czerner wrote: > Allow parameter value to be empty by spcifying fs_param_can_be_empty ^ specifying Other than that, the patch looks fine: Reviewed-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx> > + if (!*param->string && (p->flags & fs_param_can_be_empty)) > + return 0; > b = lookup_constant(bool_names, param->string, -1); > if (b == -1) > return fs_param_bad_value(log, param); > @@ -211,8 +213,11 @@ int fs_param_is_u32(struct p_log *log, const struct fs_parameter_spec *p, > struct fs_parameter *param, struct fs_parse_result *result) > { > int base = (unsigned long)p->data; > - if (param->type != fs_value_is_string || > - kstrtouint(param->string, base, &result->uint_32) < 0) > + if (param->type != fs_value_is_string) > + return fs_param_bad_value(log, param); > + if (!*param->string && (p->flags & fs_param_can_be_empty)) > + return 0; > + if (kstrtouint(param->string, base, &result->uint_32) < 0) > return fs_param_bad_value(log, param); > return 0; > } > @@ -221,8 +226,11 @@ EXPORT_SYMBOL(fs_param_is_u32); > int fs_param_is_s32(struct p_log *log, const struct fs_parameter_spec *p, > struct fs_parameter *param, struct fs_parse_result *result) > { > - if (param->type != fs_value_is_string || > - kstrtoint(param->string, 0, &result->int_32) < 0) > + if (param->type != fs_value_is_string) > + return fs_param_bad_value(log, param); > + if (!*param->string && (p->flags & fs_param_can_be_empty)) > + return 0; > + if (kstrtoint(param->string, 0, &result->int_32) < 0) > return fs_param_bad_value(log, param); > return 0; > } > @@ -231,8 +239,11 @@ EXPORT_SYMBOL(fs_param_is_s32); > int fs_param_is_u64(struct p_log *log, const struct fs_parameter_spec *p, > struct fs_parameter *param, struct fs_parse_result *result) > { > - if (param->type != fs_value_is_string || > - kstrtoull(param->string, 0, &result->uint_64) < 0) > + if (param->type != fs_value_is_string) > + return fs_param_bad_value(log, param); > + if (!*param->string && (p->flags & fs_param_can_be_empty)) > + return 0; > + if (kstrtoull(param->string, 0, &result->uint_64) < 0) > return fs_param_bad_value(log, param); > return 0; > } > @@ -244,6 +255,8 @@ int fs_param_is_enum(struct p_log *log, const struct fs_parameter_spec *p, > const struct constant_table *c; > if (param->type != fs_value_is_string) > return fs_param_bad_value(log, param); > + if (!*param->string && (p->flags & fs_param_can_be_empty)) > + return 0; > c = __lookup_constant(p->data, param->string); > if (!c) > return fs_param_bad_value(log, param); > @@ -255,7 +268,8 @@ EXPORT_SYMBOL(fs_param_is_enum); > int fs_param_is_string(struct p_log *log, const struct fs_parameter_spec *p, > struct fs_parameter *param, struct fs_parse_result *result) > { > - if (param->type != fs_value_is_string || !*param->string) > + if (param->type != fs_value_is_string || > + (!*param->string && !(p->flags & fs_param_can_be_empty))) > return fs_param_bad_value(log, param); > return 0; > } > @@ -275,7 +289,8 @@ int fs_param_is_fd(struct p_log *log, const struct fs_parameter_spec *p, > { > switch (param->type) { > case fs_value_is_string: > - if (kstrtouint(param->string, 0, &result->uint_32) < 0) > + if ((!*param->string && !(p->flags & fs_param_can_be_empty)) || > + kstrtouint(param->string, 0, &result->uint_32) < 0) > break; > if (result->uint_32 <= INT_MAX) > return 0; > diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h > index aab0ffc6bac6..f103c91139d4 100644 > --- a/include/linux/fs_parser.h > +++ b/include/linux/fs_parser.h > @@ -42,7 +42,7 @@ struct fs_parameter_spec { > u8 opt; /* Option number (returned by fs_parse()) */ > unsigned short flags; > #define fs_param_neg_with_no 0x0002 /* "noxxx" is negative param */ > -#define fs_param_neg_with_empty 0x0004 /* "xxx=" is negative param */ > +#define fs_param_can_be_empty 0x0004 /* "xxx=" is allowed */ > #define fs_param_deprecated 0x0008 /* The param is deprecated */ > const void *data; > }; > -- > 2.31.1 > -- Carlos