Allow parameter value to be empty by spcifying fs_param_can_be_empty
flag.
Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/fs_parser.c | 31 +++++++++++++++++++++++--------
include/linux/fs_parser.h | 2 +-
2 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/fs/fs_parser.c b/fs/fs_parser.c
index 3df07c0e32b3..ed40ce5742fd 100644
--- a/fs/fs_parser.c
+++ b/fs/fs_parser.c
@@ -199,6 +199,8 @@ int fs_param_is_bool(struct p_log *log, const struct fs_parameter_spec *p,
int b;
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;
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
