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, 36 insertions, 0 deletions

diff --git a/fs/adfs/file.c b/fs/adfs/file.c
new file mode 100644
index 000000000..d056d48c6
--- /dev/null
+++ b/fs/adfs/file.c
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/adfs/file.c
+ *
+ * Copyright (C) 1997-1999 Russell King
+ * from:
+ *
+ *  linux/fs/ext2/file.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ *  from
+ *
+ *  linux/fs/minix/file.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  adfs regular file handling primitives           
+ */
+#include "adfs.h"
+
+const struct file_operations adfs_file_operations = {
+	.llseek		= generic_file_llseek,
+	.read_iter	= generic_file_read_iter,
+	.mmap_prepare	= generic_file_mmap_prepare,
+	.fsync		= simple_fsync,
+	.write_iter	= generic_file_write_iter,
+	.splice_read	= filemap_splice_read,
+};
+
+const struct inode_operations adfs_file_inode_operations = {
+	.setattr	= adfs_setattr,
+};