syslog: Fix heap buffer overflow in __vsyslog_internal (CVE-2023-6779)
__vsyslog_internal used the return value of snprintf/vsnprintf to
calculate buffer sizes for memory allocation. If these functions (for
any reason) failed and returned -1, the resulting buffer would be too
small to hold output. This commit fixes that.
All snprintf/vsnprintf calls are checked for negative return values and
the function silently returns upon encountering them.
Reviewed-by:
Carlos O'Donell <carlos@redhat.com>
Loading