On Mon, May 06, 2024 at 10:43:02AM +0200, Michal Privoznik wrote:
Strictly speaking, xdrproc_t is declared as following:
typedef bool_t (*xdrproc_t)(XDR *, ...);
But our rpcgen generates properly typed functions, e.g.:
bool_t xdr_virNetMessageError(XDR *xdrs, virNetMessageError *objp)
Now, these functions of ours are passed around as callbacks (via an argument of xdrproc_t type), for instance in virNetMessageEncodePayload(). But these two types are strictly different. We silence the compiler by typecasting the callbacks when passing them, but strictly speaking - calling such callback later, when a function of xdrproc_t is expected is an undefined behavior.
Ideally, we would fix our rpcgen to generate proper function headers, but: a) my brain is too small to do that, and b) we would lose compiler protection if an xdr_*() function is called directly but argument of a wrong type is passed.
The right solution is to finish my previous work to throw away libtirpc, in favour of generating libvirt code that natively works with virNetMessage.
Silence UBSAN for now.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- meson.build | 13 +++++++++++++ 1 file changed, 13 insertions(+)
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|