On Fri, Dec 30, 2022 at 07:00:16PM +0800, Jun Nie wrote: > The ea block expansion need to access s_root while it is > already set as NULL when umount is triggered. Refuse this > request to avoid panic. > > Reported-by: syzbot+2dacb8f015bf1420155f@xxxxxxxxxxxxxxxxxxxxxxxxx > Link: https://syzkaller.appspot.com/bug?id=3613786cb88c93aa1c6a279b1df6a7b201347d08 > Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx> > --- > fs/ext4/xattr.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c > index 235a517d9c17..ac58494e49b6 100644 > --- a/fs/ext4/xattr.c > +++ b/fs/ext4/xattr.c > @@ -1422,6 +1422,12 @@ static struct inode *ext4_xattr_inode_create(handle_t *handle, > uid_t owner[2] = { i_uid_read(inode), i_gid_read(inode) }; > int err; > > + if (inode->i_sb->s_root == NULL) { > + ext4_error(inode->i_sb, > + "refuse to create EA inode when umounting"); > + return ERR_PTR(-EINVAL); > + } > + Why is an xattr being set during unmount? - Eric
