[php-maint] Bug#405067: php5-cli: Segfault after infinite recursion inside pcre - random memory corruption?

Richard Atterer atterer at debian.org
Sun Dec 31 11:51:39 UTC 2006


On Sat, Dec 30, 2006 at 10:23:06PM +0100, Richard Atterer wrote:
> One more thing: I also tried to trim down the example further by reducing 
> the length of the subject string. This gives weird results:

The following has occurred to me: The program starts crashing when the 
region matched by the regex (begins with the opening <?php) is about 4000 
bytes long. At this point, the stack contains some 8100 stack frames, half 
of them on ./pcre_exec.c:1190, the other half on ./pcre_exec.c:677.

Thus, it is possible that the special input causes one recursive step 
(i.e., one call through ./pcre_exec.c:677) for each character that is 
consumed.

Cheers,

  Richard

-- 
  __   _
  |_) /|  Richard Atterer
  | \/¯|  http://geht.net.gibts.bei.atterer.net
  ¯ '` ¯




More information about the pkg-php-maint mailing list