libxml2: Memory leak in xmlParseBalancedChunkMemoryRecover (CVE-2019-19956)

xmlParseBalancedChunkMemoryRecover in parser.c in libxml2 before 2.9.10 has a memory leak related to newDoc->oldNs.

References:

• https://gitlab.gnome.org/GNOME/libxml2/issues/82
• https://nvd.nist.gov/vuln/detail/CVE-2019-19956

Patch:

https://gitlab.gnome.org/GNOME/libxml2/commit/5a02583c7e683896d84878bd90641d8d9b0d0549

Affected branches:

• master (fb5111db)
• 3.11-stable (fb5111db)
• 3.10-stable
• 3.9-stable
• 3.8-stable