The -ftrivial-auto-var-init=zero usage guarantees implicit zero initializers for all stack variables. Thus most bug reports relying on undefined behaviour from lack of variable initialization will not be security issues, or even bugs.
Reviewed-by: Marc-André Lureau <[email protected]> Signed-off-by: Daniel P. Berrangé <[email protected]> --- docs/system/security.rst | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/docs/system/security.rst b/docs/system/security.rst index af626a4230..8c42d1a6d8 100644 --- a/docs/system/security.rst +++ b/docs/system/security.rst @@ -143,6 +143,16 @@ an issue as a normal bug. which case plain manipulation of the stream is not considered as an attack vector. +* **uninitialized stack variables**. If the bug scenario relies on + undefined behaviour from stack variables that lack explicit + initialization, it will not usually be considered a security flaw. + The build system adds '-ftrivial-auto-var-init=zero', which is + available in both the supported compilers (GCC and CLang) and + ensures all stack variables have implicit zero-initializers. + This eliminates undefined behaviour and usually gives the + correct desired initialization value, eliminating most of the + bug scenarios wrt uninitialized stack variables. + * **low severity impact**. As a catch all rule, issues which are judged to have a "low" severity impact on the system will usually not justify handling as security bugs, nor assignment -- 2.55.0
