From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
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@xxxxxxxxxxx>
---
Changes in v3:
- Remove validate_constant_table() instead of fixing it
- Link to v2: https://lore.kernel.org/r/20250411-fix_fs-v2-2-5d3395c102e4@xxxxxxxxxxx
Changes in v2:
- Remove fixes tag for remaining patches
- Add more comment for the NULL pointer dereference issue
- Link to v1: https://lore.kernel.org/r/20250410-fix_fs-v1-3-7c14ccc8ebaa@xxxxxxxxxxx
---
Documentation/filesystems/mount_api.rst | 15 ----------
fs/fs_parser.c | 49 ---------------------------------
include/linux/fs_parser.h | 5 ----
3 files changed, 69 deletions(-)
diff --git a/Documentation/filesystems/mount_api.rst b/Documentation/filesystems/mount_api.rst
index d92c276f1575af11370dcd4a5d5d0ac97c4d7f4c..cf56086bbd6622a07bbb1e283a86fea40a98a8e6 100644
--- a/Documentation/filesystems/mount_api.rst
+++ b/Documentation/filesystems/mount_api.rst
@@ -753,21 +753,6 @@ process the parameters it is given.
If a match is found, the corresponding value is returned. If a match
isn't found, the not_found value is returned instead.
- * ::
-
- bool validate_constant_table(const struct constant_table *tbl,
- size_t tbl_size,
- int low, int high, int special);
-
- Validate a constant table. Checks that all the elements are appropriately
- ordered, that there are no duplicates and that the values are between low
- and high inclusive, though provision is made for one allowable special
- value outside of that range. If no special value is required, special
- should just be set to lie inside the low-to-high range.
-
- If all is good, true is returned. If the table is invalid, errors are
- logged to the kernel log buffer and false is returned.
-
* ::
bool fs_validate_description(const char *name,
diff --git a/fs/fs_parser.c b/fs/fs_parser.c
index e635a81e17d965df78ffef27f6885cd70996c6dd..07a78a5064d05009148fa9780f3e031cd3a9b529 100644
--- a/fs/fs_parser.c
+++ b/fs/fs_parser.c
@@ -379,55 +379,6 @@ int fs_param_is_path(struct p_log *log, const struct fs_parameter_spec *p,
EXPORT_SYMBOL(fs_param_is_path);
#ifdef CONFIG_VALIDATE_FS_PARSER
-/**
- * validate_constant_table - Validate a constant table
- * @tbl: The constant table to validate.
- * @tbl_size: The size of the table.
- * @low: The lowest permissible value.
- * @high: The highest permissible value.
- * @special: One special permissible value outside of the range.
- */
-bool validate_constant_table(const struct constant_table *tbl, size_t tbl_size,
- int low, int high, int special)
-{
- size_t i;
- bool good = true;
-
- if (tbl_size == 0) {
- pr_warn("VALIDATE C-TBL: Empty\n");
- return true;
- }
-
- for (i = 0; i < tbl_size; i++) {
- if (!tbl[i].name) {
- pr_err("VALIDATE C-TBL[%zu]: Null\n", i);
- good = false;
- } else if (i > 0 && tbl[i - 1].name) {
- int c = strcmp(tbl[i-1].name, tbl[i].name);
-
- if (c == 0) {
- pr_err("VALIDATE C-TBL[%zu]: Duplicate %s\n",
- i, tbl[i].name);
- good = false;
- }
- if (c > 0) {
- pr_err("VALIDATE C-TBL[%zu]: Missorted %s>=%s\n",
- i, tbl[i-1].name, tbl[i].name);
- good = false;
- }
- }
-
- if (tbl[i].value != special &&
- (tbl[i].value < low || tbl[i].value > high)) {
- pr_err("VALIDATE C-TBL[%zu]: %s->%d const out of range (%d-%d)\n",
- i, tbl[i].name, tbl[i].value, low, high);
- good = false;
- }
- }
-
- return good;
-}
-
/**
* fs_validate_description - Validate a parameter description
* @name: The parameter name to search for.
diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h
index 53e566efd5fd133d19e313e494b975612a227b77..8d1c2fdd382fb51aee3ccdcc49735d7441581c26 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; }
---
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
change-id: 20250410-fix_fs-6e0a97c4e59f
Best regards,
--
Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
