1 files changed, 20 insertions, 22 deletions

diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index 6e72e5ad42..f4b1c8b42a 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -74,7 +74,18 @@ out:
 	return 0;
 }
 
-static int proc_fdinfo_access_allowed(struct inode *inode)
+static int seq_fdinfo_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, seq_show, inode);
+}
+
+/**
+ * Shared /proc/pid/fdinfo and /proc/pid/fdinfo/fd permission helper to ensure
+ * that the current task has PTRACE_MODE_READ in addition to the normal
+ * POSIX-like checks.
+ */
+static int proc_fdinfo_permission(struct mnt_idmap *idmap, struct inode *inode,
+				  int mask)
 {
 	bool allowed = false;
 	struct task_struct *task = get_proc_task(inode);
@@ -88,18 +99,13 @@ static int proc_fdinfo_access_allowed(struct inode *inode)
 	if (!allowed)
 		return -EACCES;
 
-	return 0;
+	return generic_permission(idmap, inode, mask);
 }
 
-static int seq_fdinfo_open(struct inode *inode, struct file *file)
-{
-	int ret = proc_fdinfo_access_allowed(inode);
-
-	if (ret)
-		return ret;
-
-	return single_open(file, seq_show, inode);
-}
+static const struct inode_operations proc_fdinfo_file_inode_operations = {
+	.permission	= proc_fdinfo_permission,
+	.setattr	= proc_setattr,
+};
 
 static const struct file_operations proc_fdinfo_file_operations = {
 	.open		= seq_fdinfo_open,
@@ -388,6 +394,8 @@ static struct dentry *proc_fdinfo_instantiate(struct dentry *dentry,
 	ei = PROC_I(inode);
 	ei->fd = data->fd;
 
+	inode->i_op = &proc_fdinfo_file_inode_operations;
+
 	inode->i_fop = &proc_fdinfo_file_operations;
 	tid_fd_update_inode(task, inode, 0);
 
@@ -407,23 +415,13 @@ static int proc_readfdinfo(struct file *file, struct dir_context *ctx)
 				  proc_fdinfo_instantiate);
 }
 
-static int proc_open_fdinfo(struct inode *inode, struct file *file)
-{
-	int ret = proc_fdinfo_access_allowed(inode);
-
-	if (ret)
-		return ret;
-
-	return 0;
-}
-
 const struct inode_operations proc_fdinfo_inode_operations = {
 	.lookup		= proc_lookupfdinfo,
+	.permission	= proc_fdinfo_permission,
 	.setattr	= proc_setattr,
 };
 
 const struct file_operations proc_fdinfo_operations = {
-	.open		= proc_open_fdinfo,
 	.read		= generic_read_dir,
 	.iterate_shared	= proc_readfdinfo,
 	.llseek		= generic_file_llseek,