From: Steven Rostedt (VMware) rostedt@goodmis.org
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@gandalf.local.home
Cc: Kees Cook keescook@chromium.org Cc: Ingo Molnar mingo@kernel.org Cc: Andrew Morton akpm@linux-foundation.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Al Viro viro@zeniv.linux.org.uk Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Yabin Cui yabinc@google.com Cc: Christian Brauner christian.brauner@ubuntu.com Cc: stable@vger.kernel.org Fixes: 4282d60689d4f ("tracefs: Add new tracefs file system") Reported-by: Kalesh Singh kaleshsingh@google.com Reported: https://lore.kernel.org/all/CAC_TJve8MMAv+H_NdLSJXZUSoxOEq2zB_pVaJ9p=7H6Bu3X... Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/tracefs/inode.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -414,6 +414,8 @@ 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); @@ -436,6 +438,8 @@ 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);