X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fstring%2Fmemmem.c;h=54a66e466aac1dce4e7312cb30206d4f52d6ab4c;hb=11ce1b133d594b6a454d3e8d5941e7a6a432c42b;hp=3b1ae18316a1d355bc6e2eabb46648060cf7decb;hpb=476cd1d96560aaf7f210319597556e7fbcd60469;p=musl

diff --git a/src/string/memmem.c b/src/string/memmem.c
index 3b1ae183..54a66e46 100644
--- a/src/string/memmem.c
+++ b/src/string/memmem.c
@@ -5,27 +5,27 @@
 static char *twobyte_memmem(const unsigned char *h, size_t k, const unsigned char *n)
 {
 	uint16_t nw = n[0]<<8 | n[1], hw = h[0]<<8 | h[1];
-	for (h++, k--; k; k--, hw = hw<<8 | *++h)
-		if (hw == nw) return (char *)h-1;
-	return 0;
+	for (h+=2, k-=2; k; k--, hw = hw<<8 | *h++)
+		if (hw == nw) return (char *)h-2;
+	return hw == nw ? (char *)h-2 : 0;
 }
 
 static char *threebyte_memmem(const unsigned char *h, size_t k, const unsigned char *n)
 {
 	uint32_t nw = n[0]<<24 | n[1]<<16 | n[2]<<8;
 	uint32_t hw = h[0]<<24 | h[1]<<16 | h[2]<<8;
-	for (h+=2, k-=2; k; k--, hw = (hw|*++h)<<8)
-		if (hw == nw) return (char *)h-2;
-	return 0;
+	for (h+=3, k-=3; k; k--, hw = (hw|*h++)<<8)
+		if (hw == nw) return (char *)h-3;
+	return hw == nw ? (char *)h-3 : 0;
 }
 
 static char *fourbyte_memmem(const unsigned char *h, size_t k, const unsigned char *n)
 {
 	uint32_t nw = n[0]<<24 | n[1]<<16 | n[2]<<8 | n[3];
 	uint32_t hw = h[0]<<24 | h[1]<<16 | h[2]<<8 | h[3];
-	for (h+=3, k-=3; k; k--, hw = hw<<8 | *++h)
-		if (hw == nw) return (char *)h-3;
-	return 0;
+	for (h+=4, k-=4; k; k--, hw = hw<<8 | *h++)
+		if (hw == nw) return (char *)h-4;
+	return hw == nw ? (char *)h-4 : 0;
 }
 
 #define MAX(a,b) ((a)>(b)?(a):(b))
@@ -112,8 +112,8 @@ static char *twoway_memmem(const unsigned char *h, const unsigned char *z, const
 		}
 
 		/* Compare right half */
-		for (k=MAX(ms+1,mem); n[k] && n[k] == h[k]; k++);
-		if (n[k]) {
+		for (k=MAX(ms+1,mem); k<l && n[k] == h[k]; k++);
+		if (k < l) {
 			h += k-ms;
 			mem = 0;
 			continue;
@@ -140,6 +140,7 @@ void *memmem(const void *h0, size_t k, const void *n0, size_t l)
 	h = memchr(h0, *n, k);
 	if (!h || l==1) return (void *)h;
 	k -= h - (const unsigned char *)h0;
+	if (k<l) return 0;
 	if (l==2) return twobyte_memmem(h, k, n);
 	if (l==3) return threebyte_memmem(h, k, n);
 	if (l==4) return fourbyte_memmem(h, k, n);