Subject: Re: CPPCheck found 24 high risk bugs in Git v.1.8.3.4

From: Andreas Schwab <[email-masked]>
Date: Tue, 20 Aug 2013 20:44:37 +0200

Erik Faye-Lund <[email-masked]> writes:

> diff --git a/compat/win32/syslog.c b/compat/win32/syslog.c
> index d015e43..0641f4e 100644
> --- a/compat/win32/syslog.c
> +++ b/compat/win32/syslog.c
> @@ -43,11 +43,14 @@ void syslog(int priority, const char *fmt, ...)
>   va_end(ap);
>
>   while ((pos = strstr(str, "%1")) != NULL) {
> - str = realloc(str, ++str_len + 1);
> - if (!str) {
> + char *tmp = realloc(str, ++str_len + 1);
> + if (!tmp) {
>   warning("realloc failed: '%s'", strerror(errno));
> + free(str);
>   return;
>   }
> + pos = tmp + (pos - str);

Pedantically, this is undefined (uses of both pos and str may trap after
realloc has freed the original pointer), it is better to calculate the
difference before calling realloc.

Andreas.

-- 
Andreas Schwab, [email-masked]
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