diff --git a/pwnlib/elf/elf.py b/pwnlib/elf/elf.py
index 42d2dff35..8c931be6c 100644
--- a/pwnlib/elf/elf.py
+++ b/pwnlib/elf/elf.py
@@ -926,10 +926,12 @@ def search(self, needle, writable = False):
         for seg in segments:
             addr   = seg.header.p_vaddr
             memsz  = seg.header.p_memsz
-            zeroed = memsz - seg.header.p_filesz
+            filesz = seg.header.p_filesz
+            zeroed = memsz - filesz
             offset = seg.header.p_offset
-            data   = self.mmap[offset:offset+memsz]
+            data   = self.mmap[offset:offset+filesz]
             data   += '\x00' * zeroed
+            assert len(data) == memsz
             offset = 0
             while True:
                 offset = data.find(needle, offset)