sysctl: Don't call sysctl_follow_link unless we are a link.
There are no functional changes. Just code motion to make it
clear that we don't follow a link between sysctl roots unless the
directory entry actually is a link.
Suggested-by: Lucian Adrian Grijincu <lucian.grijincu@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index e5601dc..a7708b7 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -451,10 +451,12 @@
if (!p)
goto out;
- ret = sysctl_follow_link(&h, &p, current->nsproxy);
- err = ERR_PTR(ret);
- if (ret)
- goto out;
+ if (S_ISLNK(p->mode)) {
+ ret = sysctl_follow_link(&h, &p, current->nsproxy);
+ err = ERR_PTR(ret);
+ if (ret)
+ goto out;
+ }
err = ERR_PTR(-ENOMEM);
inode = proc_sys_make_inode(dir->i_sb, h ? h : head, p);
@@ -601,10 +603,12 @@
int err, ret = 0;
head = sysctl_head_grab(head);
- /* It is not an error if we can not follow the link ignore it */
- err = sysctl_follow_link(&head, &table, current->nsproxy);
- if (err)
- goto out;
+ if (S_ISLNK(table->mode)) {
+ /* It is not an error if we can not follow the link ignore it */
+ err = sysctl_follow_link(&head, &table, current->nsproxy);
+ if (err)
+ goto out;
+ }
ret = proc_sys_fill_cache(filp, dirent, filldir, head, table);
out:
@@ -950,10 +954,6 @@
struct ctl_dir *dir;
int ret;
- /* Get out quickly if not a link */
- if (!S_ISLNK((*pentry)->mode))
- return 0;
-
ret = 0;
spin_lock(&sysctl_lock);
root = (*pentry)->data;