fs/fs_parse: Remove unused and problematic validate_constant_table()

Remove validate_constant_table() since:

- It has no caller.

- It has below 3 bugs for good constant table array array[] which must
  end with a empty entry, and take below invocation for explaination:
  validate_constant_table(array, ARRAY_SIZE(array), ...)

  - Always return wrong value due to the last empty entry.
  - Imprecise error message for missorted case.
  - Potential NULL pointer dereference since the last pr_err() may use
    @tbl[i].name NULL pointer to print the last empty entry's name.

Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/20250415-fix_fs-v4-1-5d575124a3ff@quicinc.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

1 files changed, 0 insertions, 5 deletions

diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h
index 5057faf4f091..5a0e897cae80 100644
--- a/include/linux/fs_parser.h
+++ b/include/linux/fs_parser.h
@@ -87,14 +87,9 @@ extern int lookup_constant(const struct constant_table tbl[], const char *name,
 extern const struct constant_table bool_names[];
 
 #ifdef CONFIG_VALIDATE_FS_PARSER
-extern bool validate_constant_table(const struct constant_table *tbl, size_t tbl_size,
-				    int low, int high, int special);
 extern bool fs_validate_description(const char *name,
 				    const struct fs_parameter_spec *desc);
 #else
-static inline bool validate_constant_table(const struct constant_table *tbl, size_t tbl_size,
-					   int low, int high, int special)
-{ return true; }
 static inline bool fs_validate_description(const char *name,
 					   const struct fs_parameter_spec *desc)
 { return true; }