From: Rich Felker <dalias@aerifal.cx>
Date: Mon, 30 Apr 2012 06:56:47 +0000 (-0400)
Subject: fix off-by-one error that caused uninitialized memory read in floatscan
X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=commitdiff_plain;h=28c5d46d844684feba2ddfc9027ea308d8d3612c;hp=e5a9b50e973aadff2e6303d01be8807b1fb9c325

fix off-by-one error that caused uninitialized memory read in floatscan

this caused misreading of certain floating point values that are exact
multiples of large powers of ten, unpredictable depending on prior
stack contents.
---

diff --git a/src/internal/floatscan.c b/src/internal/floatscan.c
index f80db383..4b335f5c 100644
--- a/src/internal/floatscan.c
+++ b/src/internal/floatscan.c
@@ -244,7 +244,7 @@ static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int po
 
 	/* Assemble desired bits into floating point variable */
 	for (y=i=0; i<LD_B1B_DIG; i++) {
-		if ((a+i & MASK)==z) x[z=(z+1 & MASK)] = 0;
+		if ((a+i & MASK)==z) x[(z=(z+1 & MASK))-1] = 0;
 		y = 1000000000.0L * y + x[a+i & MASK];
 	}