From c54f978acec617b9583d3ec8455724dbe20a1b9f Mon Sep 17 00:00:00 2001
From: max-amb <max_a@e.email>
Date: Thu, 11 Jun 2026 19:23:54 +0100
Subject: [PATCH 1/2] chown: changing group to users group #12751

---
 src/uu/chown/src/chown.rs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/uu/chown/src/chown.rs b/src/uu/chown/src/chown.rs
index ac71abd3804..1221a128404 100644
--- a/src/uu/chown/src/chown.rs
+++ b/src/uu/chown/src/chown.rs
@@ -16,6 +16,7 @@ use uucore::error::{FromIo, UResult, USimpleError};
 
 use clap::{Arg, ArgAction, ArgMatches, Command};
 
+use core::write;
 use std::fs;
 use std::os::unix::fs::MetadataExt;
 
@@ -194,6 +195,7 @@ fn parse_gid(group: &str, spec: &str) -> UResult<Option<u32>> {
 /// * `"owner:group"`,
 /// * `"owner"`,
 /// * `":group"`,
+/// * `"owner:"`,
 ///
 /// and the owner or group can be specified either as an ID or a
 /// name. The `sep` argument specifies which character to use as a
@@ -230,7 +232,13 @@ fn parse_spec(spec: &str, sep: char) -> UResult<(Option<u32>, Option<u32>)> {
         ));
     }
 
-    Ok((uid, gid))
+    if gid.is_none() && !user.is_empty() && spec.ends_with(':') {
+        // we have input of the form user: and should change the group to the users login group as
+        // per GNU
+        Ok((uid, Some(entries::usr2gid(user)?)))
+    } else {
+        Ok((uid, gid))
+    }
 }
 
 #[cfg(test)]

From def806f691cbe3dda78465481ca3a6938095901f Mon Sep 17 00:00:00 2001
From: max-amb <max_a@e.email>
Date: Thu, 11 Jun 2026 19:26:06 +0100
Subject: [PATCH 2/2] Removed accidental import

---
 src/uu/chown/src/chown.rs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/uu/chown/src/chown.rs b/src/uu/chown/src/chown.rs
index 1221a128404..4e4a7c052dc 100644
--- a/src/uu/chown/src/chown.rs
+++ b/src/uu/chown/src/chown.rs
@@ -16,7 +16,6 @@ use uucore::error::{FromIo, UResult, USimpleError};
 
 use clap::{Arg, ArgAction, ArgMatches, Command};
 
-use core::write;
 use std::fs;
 use std::os::unix::fs::MetadataExt;