From: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> commit ee7f3666995d8537dec17b1d35425f28877671a9 upstream. If directories in tracefs have their ownership changed, then any new files and directories that are created under those directories should inherit the ownership of the director they are created in. Link: https://lkml.kernel.org/r/20211208075720.4855d180@xxxxxxxxxxxxxxxxxx Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Yabin Cui <yabinc@xxxxxxxxxx> Cc: Christian Brauner <christian.brauner@xxxxxxxxxx> 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> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/tracefs/inode.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -409,6 +409,8 @@ struct dentry *tracefs_create_file(const inode->i_mode = mode; inode->i_fop = fops ? fops : &tracefs_file_operations; inode->i_private = data; + inode->i_uid = d_inode(dentry->d_parent)->i_uid; + inode->i_gid = d_inode(dentry->d_parent)->i_gid; d_instantiate(dentry, inode); fsnotify_create(dentry->d_parent->d_inode, dentry); return end_creating(dentry); @@ -431,6 +433,8 @@ static struct dentry *__create_dir(const 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 = d_inode(dentry->d_parent)->i_uid; + inode->i_gid = d_inode(dentry->d_parent)->i_gid; /* directory inodes start off with i_nlink == 2 (for "." entry) */ inc_nlink(inode);