From b8b5801478e9cdd1c74bd392017b944dcc0891dc Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Mon, 2 Feb 2015 10:00:44 -0500
Subject: [PATCH] to_char():  prevent accesses beyond the allocated buffer

Previously very long field masks for floats could access memory
beyond the existing buffer allocated to hold the result.

Reported by Andres Freund and Peter Geoghegan.	Backpatch to all
supported versions.

Security: CVE-2015-0241
---
 src/backend/utils/adt/formatting.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index e17bea26615..6d4cd1feade 100644
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -4416,7 +4416,9 @@ NUM_numpart_to_char(NUMProc *Np, int id)
 					Np->num_in = TRUE;
 				}
 			}
-			++Np->number_p;
+			/* do no exceed string length */
+			if (*Np->number_p)
+				++Np->number_p;
 		}
 
 		end = Np->num_count + (Np->out_pre_spaces ? 1 : 0) + (IS_DECIMAL(Np->Num) ? 1 : 0);