From 1e2328e762548c7d17b7ba8ded9f409d05710dd1 Mon Sep 17 00:00:00 2001
From: Carlos Neira <cneirabustos@gmail.com>
Date: Wed, 4 Mar 2020 17:41:55 -0300
Subject: [PATCH] fs/nsfs.c: Added ns_match
ns_match returns true if the namespace inode and dev_t matches the ones
provided by the caller.
Signed-off-by: Carlos Neira <cneirabustos@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200304204157.58695-2-cneirabustos@gmail.com
---
fs/nsfs.c | 14 ++++++++++++++
include/linux/proc_ns.h | 2 ++
2 files changed, 16 insertions(+)
diff --git a/fs/nsfs.c b/fs/nsfs.c
index b13bfd406820..4f1205725cfe 100644
--- a/fs/nsfs.c
+++ b/fs/nsfs.c
@@ -247,6 +247,20 @@ struct file *proc_ns_fget(int fd)
return ERR_PTR(-EINVAL);
}
+/**
+ * ns_match() - Returns true if current namespace matches dev/ino provided.
+ * @ns_common: current ns
+ * @dev: dev_t from nsfs that will be matched against current nsfs
+ * @ino: ino_t from nsfs that will be matched against current nsfs
+ *
+ * Return: true if dev and ino matches the current nsfs.
+ */
+bool ns_match(const struct ns_common *ns, dev_t dev, ino_t ino)
+{
+ return (ns->inum == ino) && (nsfs_mnt->mnt_sb->s_dev == dev);
+}
+
+
static int nsfs_show_path(struct seq_file *seq, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
index 4626b1ac3b6c..adff08bfecf9 100644
--- a/include/linux/proc_ns.h
+++ b/include/linux/proc_ns.h
@@ -85,6 +85,8 @@ typedef struct ns_common *ns_get_path_helper_t(void *);
extern int ns_get_path_cb(struct path *path, ns_get_path_helper_t ns_get_cb,
void *private_data);
+extern bool ns_match(const struct ns_common *ns, dev_t dev, ino_t ino);
+
extern int ns_get_name(char *buf, size_t size, struct task_struct *task,
const struct proc_ns_operations *ns_ops);
extern void nsfs_init(void);
--
2.30.9