1 files changed, 9 insertions, 0 deletions

diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c
index 917f564cdab1..18369d497eb8 100644
--- a/security/tomoyo/realpath.c
+++ b/security/tomoyo/realpath.c
@@ -110,6 +110,15 @@ int tomoyo_realpath_from_path2(struct path *path, char *newname,
                 spin_unlock(&dcache_lock);
                 path_put(&root);
                 path_put(&ns_root);
+                /* Prepend "/proc" prefix if using internal proc vfs mount. */
+                if (!IS_ERR(sp) && (path->mnt->mnt_parent == path->mnt) &&
+                    (strcmp(path->mnt->mnt_sb->s_type->name, "proc") == 0)) {
+                        sp -= 5;
+                        if (sp >= newname)
+                                memcpy(sp, "/proc", 5);
+                        else
+                                sp = ERR_PTR(-ENOMEM);
+                }
         }
         if (IS_ERR(sp))
                 error = PTR_ERR(sp);