diff --git a/t/t5303-pack-corruption-resilience.sh b/t/t5303-pack-corruption-resilience.sh
index 5b1250f0d2..9cb8172adf 100755
--- a/t/t5303-pack-corruption-resilience.sh
+++ b/t/t5303-pack-corruption-resilience.sh
@@ -51,7 +51,7 @@ do_corrupt_object() {
     ofs=`git show-index < ${pack}.idx | grep $1 | cut -f1 -d" "` &&
     ofs=$(($ofs + $2)) &&
     chmod +w ${pack}.pack &&
-    dd of=${pack}.pack count=1 bs=1 conv=notrunc seek=$ofs &&
+    dd of=${pack}.pack bs=1 conv=notrunc seek=$ofs &&
     test_must_fail git verify-pack ${pack}.pack
 }