diff --git a/libImaging/Histo.c b/libImaging/Histo.c
index 513c84475..0bfc8dfe9 100644
--- a/libImaging/Histo.c
+++ b/libImaging/Histo.c
@@ -41,7 +41,7 @@ ImagingHistogramNew(Imaging im)
 
     /* Create histogram descriptor */
     h = calloc(1, sizeof(struct ImagingHistogramInstance));
-    strcpy(h->mode, im->mode);
+    strncpy(h->mode, im->mode, IMAGING_MODE_LENGTH);
     h->bands = im->bands;
     h->histogram = calloc(im->pixelsize, 256 * sizeof(long));
 
diff --git a/libImaging/Imaging.h b/libImaging/Imaging.h
index 64a4fb66d..cf94dae0b 100644
--- a/libImaging/Imaging.h
+++ b/libImaging/Imaging.h
@@ -72,10 +72,12 @@ typedef struct ImagingPaletteInstance* ImagingPalette;
 #define IMAGING_TYPE_FLOAT32 2
 #define IMAGING_TYPE_SPECIAL 3 /* check mode for details */
 
+#define IMAGING_MODE_LENGTH 6+1 /* Band names ("1", "L", "P", "RGB", "RGBA", "CMYK", "YCbCr", "BGR;xy") */
+
 struct ImagingMemoryInstance {
 
     /* Format */
-    char mode[6+1];	/* Band names ("1", "L", "P", "RGB", "RGBA", "CMYK", "YCbCr", "BGR;xy") */
+    char mode[IMAGING_MODE_LENGTH];	/* Band names ("1", "L", "P", "RGB", "RGBA", "CMYK", "YCbCr", "BGR;xy") */
     int type;		/* Data type (IMAGING_TYPE_*) */
     int depth;		/* Depth (ignored in this version) */
     int bands;		/* Number of bands (1, 2, 3, or 4) */
@@ -127,7 +129,7 @@ struct ImagingAccessInstance {
 struct ImagingHistogramInstance {
 
     /* Format */
-    char mode[4+1];	/* Band names (of corresponding source image) */
+    char mode[IMAGING_MODE_LENGTH];	/* Band names (of corresponding source image) */
     int bands;		/* Number of bands (1, 3, or 4) */
 
     /* Data */
@@ -139,7 +141,7 @@ struct ImagingHistogramInstance {
 struct ImagingPaletteInstance {
 
     /* Format */
-    char mode[4+1];	/* Band names */
+    char mode[IMAGING_MODE_LENGTH];	/* Band names */
 
     /* Data */
     UINT8 palette[1024];/* Palette data (same format as image data) */
diff --git a/libImaging/Palette.c b/libImaging/Palette.c
index bd4f4f1d6..9b0dd57c4 100644
--- a/libImaging/Palette.c
+++ b/libImaging/Palette.c
@@ -37,7 +37,7 @@ ImagingPaletteNew(const char* mode)
     if (!palette)
 	return (ImagingPalette) ImagingError_MemoryError();
 
-    strcpy(palette->mode, mode);
+    strncpy(palette->mode, mode, IMAGING_MODE_LENGTH);
 
     /* Initialize to ramp */
     for (i = 0; i < 256; i++) {