libxt_TOS: avoid an undesired overflowing computation

The @bits parameter was wrongly labeled and should have been @max
already. This makes the - overflowing - 1<<bits redundant of course.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

diff --git a/extensions/tos_values.c b/extensions/tos_values.c
index 10add198a7467461b483c594e6ceaf85ac3e5f55..a65ef25db6582390afd12cd374b7f9c030427ee7 100644 (file)
--- a/extensions/tos_values.c
+++ b/extensions/tos_values.c
@@ -26,15 +26,13 @@ static const struct tos_symbol_info {
 /*
  * tos_parse_numeric - parse sth. like "15/255"
  *
- * @s:         input string
- * @info:      accompanying structure
- * @bits:      number of bits that are allowed
- *             (8 for IPv4 TOS field, 4 for IPv6 Priority Field)
+ * @str:       input string
+ * @tvm:       (value/mask) tuple
+ * @max:       maximum allowed value (must be pow(2,some_int)-1)
  */
 static bool tos_parse_numeric(const char *str, struct tos_value_mask *tvm,
-                              unsigned int bits)
+                              unsigned int max)
 {
-       const unsigned int max = (1 << bits) - 1;
        unsigned int value;
        char *end;
 
@@ -56,17 +54,22 @@ static bool tos_parse_numeric(const char *str, struct tos_value_mask *tvm,
        return true;
 }
 
+/**
+ * @str:       input string
+ * @tvm:       (value/mask) tuple
+ * @def_mask:  mask to force when a symbolic name is used
+ */
 static bool tos_parse_symbolic(const char *str, struct tos_value_mask *tvm,
     unsigned int def_mask)
 {
-       const unsigned int max = UINT8_MAX;
+       static const unsigned int max = UINT8_MAX;
        const struct tos_symbol_info *symbol;
        char *tmp;
 
        if (xtables_strtoui(str, &tmp, NULL, 0, max))
                return tos_parse_numeric(str, tvm, max);
 
-       /* Do not consider ECN bits */
+       /* Do not consider ECN bits when using preset names */
        tvm->mask = def_mask;
        for (symbol = tos_symbol_names; symbol->name != NULL; ++symbol)
                if (strcasecmp(str, symbol->name) == 0) {