Re: [libvirt] [PATCH] virnwfilterbindingobj: Introduce and use virNWFilterBindingObjStealDef

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. The solution is to unset binding->def in case of failure so it's not freed in step 5). Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- Technically, this is a v2 of: https://www.redhat.com/archives/libvir-list/2019-March/msg01209.html But since this one implements different approach than v1 I'm not marking it as such. src/conf/virnwfilterbindingobj.c | 10 ++++++++++ src/conf/virnwfilterbindingobj.h | 3 +++ src/conf/virnwfilterbindingobjlist.c | 4 ++++ src/libvirt_private.syms | 1 + 4 files changed, 18 insertions(+)