cee2dedb85
In some cases an input visitor might bail out on filling out a struct for various reasons, such as missing fields when running in strict mode. In the case of a QAPI Union type, this may lead to cases where the .kind field which encodes the union type is uninitialized. Subsequently, other visitors, such as the dealloc visitor, may use this .kind value as if it were initialized, leading to assumptions about the union type which in this case may lead to segfaults. For example, freeing an integer value. However, we can generally rely on the fact that the always-present .data void * field that we generate for these union types will always be NULL in cases where .kind is uninitialized (at least, there shouldn't be a reason where we'd do this purposefully). So pass this information on to Visitor implementation via these optional start_union/end_union interfaces so this information can be used to guard against the situation above. We will make use of this information in a subsequent patch for the dealloc visitor. Cc: qemu-stable@nongnu.org Reported-by: Fam Zheng <famz@redhat.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> |
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| .. | ||
| qmp | ||
| dealloc-visitor.h | ||
| error.h | ||
| opts-visitor.h | ||
| qmp-event.h | ||
| qmp-input-visitor.h | ||
| qmp-output-visitor.h | ||
| string-input-visitor.h | ||
| string-output-visitor.h | ||
| util.h | ||
| visitor-impl.h | ||
| visitor.h | ||