https://bugzilla.redhat.com/show_bug.cgi?id=1686927 When trying to create a nwfilter binding via nwfilterBindingCreateXML() we may encounter a crash. The sequence of functions called is as follows: 1) nwfilterBindingCreateXML() parses the XML and calls virNWFilterBindingObjListAdd() which calls virNWFilterBindingObjListAddLocked() 2) Here, @binding is not found because binding->remove is set. 3) Therefore, controls continue with creating new @binding, setting its def to the one from 1) and adding it to the hash table. 4) This fails, because the binding is still in the hash table (duplicate key is detected). 5) The control jumps to 'error' label where virNWFilterBindingObjEndAPI() is called which frees the binding definition passed. 6) Error is propagated to the caller, which calls virNWFilterBindingDefFree() over the definition again. Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx> --- src/conf/virnwfilterbindingobjlist.c | 11 ++++++----- src/conf/virnwfilterbindingobjlist.h | 2 +- src/nwfilter/nwfilter_driver.c | 5 ++--- 3 files changed, 9 insertions(+), 9 deletions(-) diff --git a/src/conf/virnwfilterbindingobjlist.c b/src/conf/virnwfilterbindingobjlist.c index 06ccbf53af..87189da642 100644 --- a/src/conf/virnwfilterbindingobjlist.c +++ b/src/conf/virnwfilterbindingobjlist.c @@ -164,23 +164,24 @@ virNWFilterBindingObjListAddObjLocked(virNWFilterBindingObjListPtr bindings, */ static virNWFilterBindingObjPtr virNWFilterBindingObjListAddLocked(virNWFilterBindingObjListPtr bindings, - virNWFilterBindingDefPtr def) + virNWFilterBindingDefPtr *def) { virNWFilterBindingObjPtr binding; /* See if a binding with matching portdev already exists */ if ((binding = virNWFilterBindingObjListFindByPortDevLocked( - bindings, def->portdevname))) { + bindings, (*def)->portdevname))) { virReportError(VIR_ERR_OPERATION_FAILED, _("binding '%s' already exists"), - def->portdevname); + (*def)->portdevname); goto error; } if (!(binding = virNWFilterBindingObjNew())) goto error; - virNWFilterBindingObjSetDef(binding, def); + virNWFilterBindingObjSetDef(binding, *def); + *def = NULL; if (virNWFilterBindingObjListAddObjLocked(bindings, binding) < 0) goto error; @@ -195,7 +196,7 @@ virNWFilterBindingObjListAddLocked(virNWFilterBindingObjListPtr bindings, virNWFilterBindingObjPtr virNWFilterBindingObjListAdd(virNWFilterBindingObjListPtr bindings, - virNWFilterBindingDefPtr def) + virNWFilterBindingDefPtr *def) { virNWFilterBindingObjPtr ret; diff --git a/src/conf/virnwfilterbindingobjlist.h b/src/conf/virnwfilterbindingobjlist.h index b0fb90f667..4047453634 100644 --- a/src/conf/virnwfilterbindingobjlist.h +++ b/src/conf/virnwfilterbindingobjlist.h @@ -35,7 +35,7 @@ virNWFilterBindingObjListFindByPortDev(virNWFilterBindingObjListPtr bindings, virNWFilterBindingObjPtr virNWFilterBindingObjListAdd(virNWFilterBindingObjListPtr bindings, - virNWFilterBindingDefPtr def); + virNWFilterBindingDefPtr *def); void virNWFilterBindingObjListRemove(virNWFilterBindingObjListPtr bindings, diff --git a/src/nwfilter/nwfilter_driver.c b/src/nwfilter/nwfilter_driver.c index fdfc6f48fa..8c2e987b5d 100644 --- a/src/nwfilter/nwfilter_driver.c +++ b/src/nwfilter/nwfilter_driver.c @@ -759,7 +759,7 @@ nwfilterBindingCreateXML(virConnectPtr conn, goto cleanup; obj = virNWFilterBindingObjListAdd(driver->bindings, - def); + &def); if (!obj) goto cleanup; @@ -775,8 +775,7 @@ nwfilterBindingCreateXML(virConnectPtr conn, virNWFilterBindingObjSave(obj, driver->bindingDir); cleanup: - if (!obj) - virNWFilterBindingDefFree(def); + virNWFilterBindingDefFree(def); virNWFilterBindingObjEndAPI(&obj); return ret; -- 2.19.2 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list