diff --git a/CHANGELOG.md b/CHANGELOG.md
index ec9fc93d906d34ecea6c9c0a41897c7bcccc371c..d7bc83d02a3a483902882ca355cf1539e0104b60 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,7 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   
 ### Fixed
   - Dup3 is supported if O_CLOEXEC is not used (i.e. hexdump) ([!228](https://storage.bsc.es/gitlab/hpc/gekkofs/-/merge_requests/228))
+  - gkfs_do_write uses int instead of ssize_t causing overflow ([!229](https://storage.bsc.es/gitlab/hpc/gekkofs/-/merge_requests/229))
 
 
 ## [0.9.4] - 2025-03
diff --git a/src/client/gkfs_functions.cpp b/src/client/gkfs_functions.cpp
index 4f7c348c8a96ee3891b1f74b70201fc740c118ec..3ca3dce19b219fcee4277f64207a031533d43426 100644
--- a/src/client/gkfs_functions.cpp
+++ b/src/client/gkfs_functions.cpp
@@ -941,7 +941,7 @@ gkfs_do_write(gkfs::filemap::OpenFile& file, const char* buf, size_t count,
     int err;
     auto path = make_unique<string>(file.path());
     auto is_append = file.get_flag(gkfs::filemap::OpenFile_flags::append);
-    auto write_size = 0;
+    ssize_t write_size = 0;
     auto num_replicas = CTX->get_replicas();
     LOG(DEBUG, "{}() path: '{}', count: '{}', offset: '{}', is_append: '{}'",
         __func__, *path, count, offset, is_append);