From: Kees Cook <keescook@chromium.org>
Date: Fri, 15 Sep 2023 20:14:05 +0000 (-0700)
Subject: udf: Annotate struct udf_bitmap with __counted_by
X-Git-Tag: v6.7-rc1~108^2~11
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d1d3fcb324eceee7c4bf34b0ac89942ee16e3b74;p=users%2Fdwmw2%2Flinux.git

udf: Annotate struct udf_bitmap with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct udf_bitmap.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Jan Kara <jack@suse.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Message-Id: <20230915201404.never.574-kees@kernel.org>
---

diff --git a/fs/udf/udf_sb.h b/fs/udf/udf_sb.h
index 9af6ff7f97472..f9a60bc1abcfc 100644
--- a/fs/udf/udf_sb.h
+++ b/fs/udf/udf_sb.h
@@ -86,7 +86,7 @@ struct udf_virtual_data {
 struct udf_bitmap {
 	__u32			s_extPosition;
 	int			s_nr_groups;
-	struct buffer_head	*s_block_bitmap[];
+	struct buffer_head	*s_block_bitmap[] __counted_by(s_nr_groups);
 };
 
 struct udf_part_map {