bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/Documentation/maintainer/configure-git.rst b/Documentation/maintainer/configure-git.rst
new file mode 100644
index 000000000..0c21f203c
--- /dev/null
+++ b/Documentation/maintainer/configure-git.rst
@@ -0,0 +1,30 @@
+Configuring Git
+===============
+
+This chapter describes maintainer level git configuration.
+
+Tagged branches used in pull requests (see
+Documentation/maintainer/pull-requests.rst) should be signed with the
+developers public GPG key. Signed tags can be created by passing
+``-u <key-id>`` to ``git tag``. However, since you would *usually* use the same
+key for the project, you can set it in the configuration and use the ``-s``
+flag. To set the default ``key-id`` use::
+
+	git config user.signingkey "keyname"
+
+Alternatively, edit your ``.git/config`` or ``~/.gitconfig`` file by hand::
+
+	[user]
+		name = Jane Developer
+		email = jd@domain.org
+		signingkey = jd@domain.org
+
+You may need to tell ``git`` to use ``gpg2``::
+
+	[gpg]
+		program = /path/to/gpg2
+
+You may also like to tell ``gpg`` which ``tty`` to use (add to your shell
+rc file)::
+
+	export GPG_TTY=$(tty)