Predict integer overflow to avoid buffer overruns.

Several functions, mostly type input functions, calculated an allocation
size such that the calculation wrapped to a small positive value when
arguments implied a sufficiently-large requirement.  Writes past the end
of the inadvertent small allocation followed shortly thereafter.
Coverity identified the path_in() vulnerability; code inspection led to
the rest.  In passing, add check_stack_depth() to prevent stack overflow
in related functions.

Back-patch to 8.4 (all supported versions).  The non-comment hstore
changes touch code that did not exist in 8.4, so that part stops at 9.0.

Noah Misch and Heikki Linnakangas, reviewed by Tom Lane.

Security: CVE-2014-0064

1 files changed, 6 insertions, 1 deletions

diff --git a/src/backend/utils/adt/tsquery.c b/src/backend/utils/adt/tsquery.c
index 90ca37b0f77..b973a534ddb 100644
--- a/src/backend/utils/adt/tsquery.c
+++ b/src/backend/utils/adt/tsquery.c
@@ -514,8 +514,13 @@ parse_tsquery(char *buf,
 		return query;
 	}
 
-	/* Pack the QueryItems in the final TSQuery struct to return to caller */
+	if (TSQUERY_TOO_BIG(list_length(state.polstr), state.sumlen))
+		ereport(ERROR,
+				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+				 errmsg("tsquery is too large")));
 	commonlen = COMPUTESIZE(list_length(state.polstr), state.sumlen);
+
+	/* Pack the QueryItems in the final TSQuery struct to return to caller */
 	query = (TSQuery) palloc0(commonlen);
 	SET_VARSIZE(query, commonlen);
 	query->size = list_length(state.polstr);