cpuset: fix error handling regression in proc_cpuset_show()

4c737b41de7f ("cgroup: make cgroup_path() and friends behave in the
style of strlcpy()") botched the conversion of proc_cpuset_show() and
broke its error handling.  It made the function return 0 on failures
and fail to handle error returns from cgroup_path_ns().  Fix it.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 793ae6fd96dc..97dd8e178786 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2698,12 +2698,13 @@ int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
         if (!buf)
                 goto out;
 
-        retval = -ENAMETOOLONG;
         css = task_get_css(tsk, cpuset_cgrp_id);
         retval = cgroup_path_ns(css->cgroup, buf, PATH_MAX,
                                 current->nsproxy->cgroup_ns);
         css_put(css);
         if (retval >= PATH_MAX)
+                retval = -ENAMETOOLONG;
+        if (retval < 0)
                 goto out_free;
         seq_puts(m, buf);
         seq_putc(m, '\n');
@@ -2711,7 +2712,7 @@ int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
 out_free:
         kfree(buf);
 out:
-        return 0;
+        return retval;
 }
 #endif /* CONFIG_PROC_PID_CPUSET */