[PATCH] tracefs: Have new files inherit the ownership of their parent

From: Steven Rostedt
Date: Tue Dec 07 2021 - 14:48:38 EST


From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

If the tracefs system is set to a specific owner and group, then the files
and directories that are created under them should inherit the owner and
group of the parent.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 4282d60689d4f ("tracefs: Add new tracefs file system")
Reported-by: Kalesh Singh <kaleshsingh@xxxxxxxxxx>
Reported: https://lore.kernel.org/all/CAC_TJve8MMAv+H_NdLSJXZUSoxOEq2zB_pVaJ9p=7H6Bu3X76g@xxxxxxxxxxxxxx/
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
fs/tracefs/inode.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index f20f575cdaef..6b16d89cf187 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c
@@ -488,6 +488,8 @@ struct dentry *tracefs_create_file(const char *name, umode_t mode,
inode->i_mode = mode;
inode->i_fop = fops ? fops : &tracefs_file_operations;
inode->i_private = data;
+ inode->i_uid = dentry->d_parent->d_inode->i_uid;
+ inode->i_gid = dentry->d_parent->d_inode->i_gid;
d_instantiate(dentry, inode);
fsnotify_create(dentry->d_parent->d_inode, dentry);
return end_creating(dentry);
@@ -510,6 +512,8 @@ static struct dentry *__create_dir(const char *name, struct dentry *parent,
inode->i_mode = S_IFDIR | S_IRWXU | S_IRUSR| S_IRGRP | S_IXUSR | S_IXGRP;
inode->i_op = ops;
inode->i_fop = &simple_dir_operations;
+ inode->i_uid = dentry->d_parent->d_inode->i_uid;
+ inode->i_gid = dentry->d_parent->d_inode->i_gid;

/* directory inodes start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
--
2.31.1