From 15a849be100b54776bcf63193c3fea598666030f Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Tue, 20 Aug 2013 00:35:38 +0200 Subject: OptsVisitor: don't try to flatten overlong integer ranges Prevent mistyped command line options from incurring high memory and CPU usage at startup. 64K elements in a range should be enough for everyone (TM). The OPTS_VISITOR_RANGE_MAX macro is public so that unit tests can construct corner cases with it. Signed-off-by: Laszlo Ersek Tested-by: Wanlong Gao Signed-off-by: Luiz Capitulino --- include/qapi/opts-visitor.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include') diff --git a/include/qapi/opts-visitor.h b/include/qapi/opts-visitor.h index 5939eeebc7..fd48c14ec8 100644 --- a/include/qapi/opts-visitor.h +++ b/include/qapi/opts-visitor.h @@ -16,6 +16,12 @@ #include "qapi/visitor.h" #include "qemu/option.h" +/* Inclusive upper bound on the size of any flattened range. This is a safety + * (= anti-annoyance) measure; wrong ranges should not cause long startup + * delays nor exhaust virtual memory. + */ +#define OPTS_VISITOR_RANGE_MAX 65536 + typedef struct OptsVisitor OptsVisitor; /* Contrarily to qemu-option.c::parse_option_number(), OptsVisitor's "int" -- cgit v1.2.1