xml2: Fix failure with xslt_process() under -fsanitize=undefined The logic of xslt_process() has never considered the fact that xsltSaveResultToString() would return NULL for an empty string (the upstream code has always done so, with a string length of 0). This would cause memcpy() to be called with a NULL pointer, something forbidden by POSIX.
Like 46ab07ffda9d and similar fixes, this is backpatched down to all the supported branches, with a test case to cover this scenario. An empty string has been always returned in xml2 in this case, based on the history of the module, so this is an old issue. Reported-by: Alexander Lakhin <[email protected]> Discussion: https://postgr.es/m/[email protected] Backpatch-through: 14 Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/0b0041b942f7ecca56efec4cb882caec0247984f Modified Files -------------- contrib/xml2/expected/xml2.out | 10 ++++++++++ contrib/xml2/expected/xml2_1.out | 6 ++++++ contrib/xml2/sql/xml2.sql | 6 ++++++ contrib/xml2/xslt_proc.c | 9 ++++++++- 4 files changed, 30 insertions(+), 1 deletion(-)
