From 376eedbaf2903e0ce7f37b3d40514733eccf6527 Mon Sep 17 00:00:00 2001
From: dergoegge <n.goeggi@gmail.com>
Date: Thu, 26 Jun 2025 14:35:29 +0100
Subject: [PATCH] libafl: fix lockfile ctr serialization

All locations reading from the lockfile expect an integer as a string,
but in `InMemoryOnDiskCorpus<I>::remove_testcase` the raw bytes of the
integer are written to the file in little endian byte order.

This may cause "ParseIntError { kind: InvalidDigit }" in e.g.
`InMemoryOnDiskCorpus<I>::save_testcase` during parsing of the file's
contents.

Fix this by writing the integer to the lockfile as a string in
`InMemoryOnDiskCorpus<I>::remove_testcase` as well.
---
 crates/libafl/src/corpus/inmemory_ondisk.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/libafl/src/corpus/inmemory_ondisk.rs b/crates/libafl/src/corpus/inmemory_ondisk.rs
index 00e598bb86..d5432a765c 100644
--- a/crates/libafl/src/corpus/inmemory_ondisk.rs
+++ b/crates/libafl/src/corpus/inmemory_ondisk.rs
@@ -490,7 +490,7 @@ impl<I> InMemoryOnDiskCorpus<I> {
                     drop(fs::remove_file(lockfile_path));
                 } else {
                     lockfile.seek(SeekFrom::Start(0))?;
-                    lockfile.write_all(&(ctr.parse::<u32>()? - 1).to_le_bytes())?;
+                    lockfile.write_all((ctr.parse::<u32>()? - 1).to_string().as_bytes())?;
                     return Ok(());
                 }
             }