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, 44 insertions, 0 deletions

diff --git a/fs/afs/Kconfig b/fs/afs/Kconfig
new file mode 100644
index 000000000..682bd8ec2
--- /dev/null
+++ b/fs/afs/Kconfig
@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config AFS_FS
+	tristate "Andrew File System support (AFS)"
+	depends on INET
+	select AF_RXRPC
+	select DNS_RESOLVER
+	select NETFS_SUPPORT
+	select CRYPTO_KRB5
+	help
+	  If you say Y here, you will get an experimental Andrew File System
+	  driver. It currently only supports unsecured read-only AFS access.
+
+	  See <file:Documentation/filesystems/afs.rst> for more information.
+
+	  If unsure, say N.
+
+config AFS_DEBUG
+	bool "AFS dynamic debugging"
+	depends on AFS_FS
+	help
+	  Say Y here to make runtime controllable debugging messages appear.
+
+	  See <file:Documentation/filesystems/afs.rst> for more information.
+
+	  If unsure, say N.
+
+config AFS_FSCACHE
+	bool "Provide AFS client caching support"
+	depends on AFS_FS=m && FSCACHE || AFS_FS=y && FSCACHE=y
+	help
+	  Say Y here if you want AFS data to be cached locally on disk through
+	  the generic filesystem cache manager
+
+config AFS_DEBUG_CURSOR
+	bool "AFS server cursor debugging"
+	depends on AFS_FS
+	help
+	  Say Y here to cause the contents of a server cursor to be dumped to
+	  the dmesg log if the server rotation algorithm fails to successfully
+	  contact a server.
+
+	  See <file:Documentation/filesystems/afs.rst> for more information.
+
+	  If unsure, say N.