[hackers] [sbase] chgrp: Pass -1 as the owner ID to chown(3) || Michael Forney

[git]

commit b29fc0b05f579d293043b130aef3338eaf052c8e
Author:     Michael Forney <mfor...@mforney.org>
AuthorDate: Fri Nov 1 19:03:00 2019 -0700
Commit:     Michael Forney <mfor...@mforney.org>
CommitDate: Fri Nov 1 19:03:00 2019 -0700

    chgrp: Pass -1 as the owner ID to chown(3)
    
    Otherwise, if the owner ID changes between stat() and chown(), we will
    revert to the previous owner while changing the group.

diff --git a/chgrp.c b/chgrp.c
index 93d7577..960ed2c 100644
--- a/chgrp.c
+++ b/chgrp.c
@@ -26,7 +26,7 @@ chgrp(const char *path, struct stat *st, void *data, struct 
recursor *r)
                chownf = chown;
        }
 
-       if (chownf(path, st->st_uid, gid) < 0) {
+       if (chownf(path, -1, gid) < 0) {
                weprintf("%s %s:", chownf_name, path);
                ret = 1;
        } else if (S_ISDIR(st->st_mode)) {