5bb5e6ee6f
If ceph_atomic_open is handed a !d_in_lookup dentry, then that means that it already passed d_revalidate so we *know* that it's negative (or at least was very recently). Just return -ENOENT in that case. This also addresses a subtle bug in dentry handling. Non-O_CREAT opens call atomic_open with the parent's i_rwsem shared, but calling d_splice_alias on a hashed dentry requires the exclusive lock. If ceph_atomic_open receives a hashed, negative dentry on a non-O_CREAT open, and another client were to race in and create the file before we issue our OPEN, ceph_fill_trace could end up calling d_splice_alias on the dentry with the new inode with insufficient locks. Cc: stable@vger.kernel.org Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.