X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fstring%2Fmemmem.c;h=54a66e466aac1dce4e7312cb30206d4f52d6ab4c;hb=b36c37f6fa9692b03bbdeda2b57b2e8a26d8f315;hp=d7e1221940b013810f1e26261357dc2609f2051b;hpb=cef0f289f666b6c963bfd11537a6d80916ff889e;p=musl

diff --git a/src/string/memmem.c b/src/string/memmem.c
index d7e12219..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))
@@ -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);