1 files changed, 16 insertions, 20 deletions

diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c
index 20614b62a9b7..d6113dbe58e0 100644
--- a/fs/proc/thread_self.c
+++ b/fs/proc/thread_self.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cache.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/pid_namespace.h>
@@ -10,18 +12,17 @@ static const char *proc_thread_self_get_link(struct dentry *dentry,
 					     struct inode *inode,
 					     struct delayed_call *done)
 {
-	struct pid_namespace *ns = inode->i_sb->s_fs_info;
+	struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
 	pid_t tgid = task_tgid_nr_ns(current, ns);
 	pid_t pid = task_pid_nr_ns(current, ns);
 	char *name;
 
 	if (!pid)
 		return ERR_PTR(-ENOENT);
-	name = kmalloc(PROC_NUMBUF + 6 + PROC_NUMBUF,
-				dentry ? GFP_KERNEL : GFP_ATOMIC);
+	name = kmalloc(10 + 6 + 10 + 1, dentry ? GFP_KERNEL : GFP_ATOMIC);
 	if (unlikely(!name))
 		return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD);
-	sprintf(name, "%d/task/%d", tgid, pid);
+	sprintf(name, "%u/task/%u", tgid, pid);
 	set_delayed_call(done, kfree_link, name);
 	return name;
 }
@@ -30,40 +31,35 @@ static const struct inode_operations proc_thread_self_inode_operations = {
 	.get_link	= proc_thread_self_get_link,
 };
 
-static unsigned thread_self_inum;
+unsigned thread_self_inum __ro_after_init;
 
 int proc_setup_thread_self(struct super_block *s)
 {
 	struct inode *root_inode = d_inode(s->s_root);
-	struct pid_namespace *ns = s->s_fs_info;
 	struct dentry *thread_self;
+	int ret = -ENOMEM;
 
 	inode_lock(root_inode);
 	thread_self = d_alloc_name(s->s_root, "thread-self");
 	if (thread_self) {
-		struct inode *inode = new_inode_pseudo(s);
+		struct inode *inode = new_inode(s);
 		if (inode) {
 			inode->i_ino = thread_self_inum;
-			inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+			simple_inode_init_ts(inode);
 			inode->i_mode = S_IFLNK | S_IRWXUGO;
 			inode->i_uid = GLOBAL_ROOT_UID;
 			inode->i_gid = GLOBAL_ROOT_GID;
 			inode->i_op = &proc_thread_self_inode_operations;
-			d_add(thread_self, inode);
-		} else {
-			dput(thread_self);
-			thread_self = ERR_PTR(-ENOMEM);
+			d_make_persistent(thread_self, inode);
+			ret = 0;
 		}
-	} else {
-		thread_self = ERR_PTR(-ENOMEM);
+		dput(thread_self);
 	}
 	inode_unlock(root_inode);
-	if (IS_ERR(thread_self)) {
-		pr_err("proc_fill_super: can't allocate /proc/thread_self\n");
-		return PTR_ERR(thread_self);
-	}
-	ns->proc_thread_self = thread_self;
-	return 0;
+
+	if (ret)
+		pr_err("proc_fill_super: can't allocate /proc/thread-self\n");
+	return ret;
 }
 
 void __init proc_thread_self_init(void)