follow symlinks to find the true passwd file before updating.
diff --git a/libbb/update_passwd.c b/libbb/update_passwd.c
index 388adf8..e99db40 100644
--- a/libbb/update_passwd.c
+++ b/libbb/update_passwd.c
@@ -52,6 +52,10 @@
int cnt = 0;
int ret = -1; /* failure */
+ filename = xmalloc_readlink_follow(filename);
+ if (filename == NULL)
+ return -1;
+
check_selinux_update_passwd(username);
/* New passwd file, "/etc/passwd+" for now */
@@ -143,6 +147,7 @@
free_mem:
free(fnamesfx);
- free((char*)username);
+ free((char *)filename);
+ free((char *)username);
return ret;
}