Hi!
On Oct 01, bar@stripped wrote:
> ChangeSet@stripped, 2007-10-01 19:01:51+05:00, bar@stripped +11 -0
> Bug#31081 server crash in regexp function
> Problem: The "regex" library written by Henry Spencer
> does not support tricky character sets like UCS2.
> Fix: convert tricky character sets to UTF8 before calling
> regex functions.
A couple of comments
> diff -Nrup a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
> --- a/sql/item_cmpfunc.cc 2007-07-16 02:03:32 +05:00
> +++ b/sql/item_cmpfunc.cc 2007-10-01 19:01:50 +05:00
> @@ -4281,47 +4332,29 @@ longlong Item_func_regex::val_int()
> {
> DBUG_ASSERT(fixed == 1);
> char buff[MAX_FIELD_WIDTH];
> + String tmp(buff,sizeof(buff),&my_charset_bin);
> + String *res= args[0]->val_str(&tmp);
>
> + if (args[0]->null_value || (!regex_is_const && regcomp(FALSE)))
> {
> + null_value= 1;
> return 0;
> }
> + null_value= 0;
> +
> + if (cmp_collation.collation != regex_lib_charset)
> {
> + /* Convert UCS2 strings to UTF8 */
> char buff2[MAX_FIELD_WIDTH];
> -
> + String tmp2(buff2, sizeof(buff), regex_lib_charset);
> + uint dummy_errors;
> + if (tmp2.copy(res->ptr(), res->length(), res->charset(),
> + regex_lib_charset, &dummy_errors))
wouldn't it be better to store tmp2 in the object, to avoid mallocs for
every val_int() call (assuming the argument is larger than
MAX_FIELD_WIDTH) ?
Same, to the less extent, applies to regcomp() method.
> diff -Nrup a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h
> --- a/sql/item_cmpfunc.h 2007-08-31 04:23:36 +05:00
> +++ b/sql/item_cmpfunc.h 2007-10-01 19:01:50 +05:00
> @@ -1313,9 +1313,12 @@ class Item_func_regex :public Item_bool_
> bool regex_is_const;
> String prev_regexp;
> DTCollation cmp_collation;
> + CHARSET_INFO *regex_lib_charset;
> + int regex_lib_flags;
> public:
> Item_func_regex(Item *a,Item *b) :Item_bool_func(a,b),
> regex_compiled(0),regex_is_const(0) {}
> + bool regcomp(bool send_error);
Should regcomp() be public ?
> void cleanup();
> longlong val_int();
Regards / Mit vielen Grüssen,
Sergei
--
__ ___ ___ ____ __
/ |/ /_ __/ __/ __ \/ / Sergei Golubchik <serg@stripped>
/ /|_/ / // /\ \/ /_/ / /__ Principal Software Developer
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