diff --git a/src/libImaging/SgiRleDecode.c b/src/libImaging/SgiRleDecode.c
index a8db11740..a4ee2e10d 100644
--- a/src/libImaging/SgiRleDecode.c
+++ b/src/libImaging/SgiRleDecode.c
@@ -183,7 +183,7 @@ ImagingSgiRleDecode(Imaging im, ImagingCodecState state, UINT8 *buf, Py_ssize_t
        each with 4 bytes per element of tablen
        Check here before we allocate any memory
     */
-    if (c->bufsize < 8 * c->tablen) {
+    if (c->bufsize < 8 * (int64_t)c->tablen) {
         state->errcode = IMAGING_CODEC_OVERRUN;
         return -1;
     }