947e492c0f
When I moved the refcount to refcount_t type I missed the fact that
refcount_inc() will result in use-after-free warning with
CONFIG_REFCOUNT_FULL=y builds.
The correct fix would be to init the reference count to 1 at allocation
time, but, unfortunately we cannot do this, as we can't undo that
in case something else fails later in the batch.
So only solution I see is to special-case the 'new entry' condition
and replace refcount_inc() with a "delayed" refcount_set(1) in this case,
as done here.
The .activate callback can be removed to simplify things, we only
need to make sure that deactivate() decrements/unlinks the entry
from the list at end of transaction phase (commit or abort).
Fixes: 12c44aba6618 ("netfilter: nft_compat: use refcnt_t type for nft_xt reference count")
Reported-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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.