From: "Steven Rostedt (VMware)" <rostedt@goodmis.org> stable inclusion from linux-4.19.221 commit 7d795454ccb2a523d1d2146bda45e6f3b45d7d9f -------------------------------- 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> Conflicts: fs/tracefs/inode.c [yyl: adjust context] Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- fs/tracefs/inode.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index 7cfb2c77a120a..f4ea7bf13386c 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -412,6 +412,8 @@ 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 = 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); @@ -433,6 +435,8 @@ static struct dentry *__create_dir(const char *name, struct dentry *parent, inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; 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); -- 2.25.1