| Message ID | 20170815040454.4223-2-famz@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 08/14/2017 11:04 PM, Fam Zheng wrote: > Signed-off-by: Fam Zheng <famz@redhat.com> A bit sparse on the 'why' - presumably, upcoming patches will fail to compile if the stub is not present, but mentioning what dependency this solves never hurts. > --- > stubs/Makefile.objs | 1 + > stubs/change-state-handler.c | 14 ++++++++++++++ > 2 files changed, 15 insertions(+) > create mode 100644 stubs/change-state-handler.c > > +++ b/stubs/change-state-handler.c > @@ -0,0 +1,14 @@ > +#include "qemu/osdep.h" > +#include "qemu-common.h" > +#include "sysemu/sysemu.h" > + > +VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb, > + void *opaque) > +{ > + return g_malloc0(1); > +} Hmm - this is NOT a VMChangeStateEntry; if it ever gets dereferenced, the caller is (probably) accessing memory out of bounds. Presumably, since it is a stub, this should never be called - and if that's the case, can we just get away with returning NULL instead (I'd rather have the caller SEGFAULT than dereference out-of-bounds into the heap, if this stub gets used inappropriately). > + > +void qemu_del_vm_change_state_handler(VMChangeStateEntry *e) > +{ > + g_free(e); And of course, if you don't allocate anything, this can be a no-op. > +} >
On Tue, 08/15 07:26, Eric Blake wrote: > On 08/14/2017 11:04 PM, Fam Zheng wrote: > > Signed-off-by: Fam Zheng <famz@redhat.com> > > A bit sparse on the 'why' - presumably, upcoming patches will fail to > compile if the stub is not present, but mentioning what dependency this > solves never hurts. > > > --- > > stubs/Makefile.objs | 1 + > > stubs/change-state-handler.c | 14 ++++++++++++++ > > 2 files changed, 15 insertions(+) > > create mode 100644 stubs/change-state-handler.c > > > > > +++ b/stubs/change-state-handler.c > > @@ -0,0 +1,14 @@ > > +#include "qemu/osdep.h" > > +#include "qemu-common.h" > > +#include "sysemu/sysemu.h" > > + > > +VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb, > > + void *opaque) > > +{ > > + return g_malloc0(1); > > +} > > Hmm - this is NOT a VMChangeStateEntry; if it ever gets dereferenced, > the caller is (probably) accessing memory out of bounds. Presumably, > since it is a stub, this should never be called - and if that's the > case, can we just get away with returning NULL instead (I'd rather have > the caller SEGFAULT than dereference out-of-bounds into the heap, if > this stub gets used inappropriately). Good point, will update this patch. > > > + > > +void qemu_del_vm_change_state_handler(VMChangeStateEntry *e) > > +{ > > + g_free(e); > > And of course, if you don't allocate anything, this can be a no-op. > > > +} > > > Fam
diff --git a/stubs/Makefile.objs b/stubs/Makefile.objs index f5b47bfd74..e69c217aff 100644 --- a/stubs/Makefile.objs +++ b/stubs/Makefile.objs @@ -19,6 +19,7 @@ stub-obj-y += is-daemonized.o stub-obj-$(CONFIG_LINUX_AIO) += linux-aio.o stub-obj-y += machine-init-done.o stub-obj-y += migr-blocker.o +stub-obj-y += change-state-handler.o stub-obj-y += monitor.o stub-obj-y += notify-event.o stub-obj-y += qtest.o diff --git a/stubs/change-state-handler.c b/stubs/change-state-handler.c new file mode 100644 index 0000000000..9833ba4e94 --- /dev/null +++ b/stubs/change-state-handler.c @@ -0,0 +1,14 @@ +#include "qemu/osdep.h" +#include "qemu-common.h" +#include "sysemu/sysemu.h" + +VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb, + void *opaque) +{ + return g_malloc0(1); +} + +void qemu_del_vm_change_state_handler(VMChangeStateEntry *e) +{ + g_free(e); +}
Signed-off-by: Fam Zheng <famz@redhat.com> --- stubs/Makefile.objs | 1 + stubs/change-state-handler.c | 14 ++++++++++++++ 2 files changed, 15 insertions(+) create mode 100644 stubs/change-state-handler.c