From: Gustavo A. R. Silva <gustavoars@kernel.org>
Date: Thu, 8 Aug 2024 22:04:04 +0000 (-0600)
Subject: smb: smb2pdu.h: Use static_assert() to check struct sizes
X-Git-Tag: v6.12~656^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5b4f3af39b6588e8de4444d8e1ccf759b40f9414;p=platform%2Fkernel%2Flinux-amlogic.git

smb: smb2pdu.h: Use static_assert() to check struct sizes

Commit 9f9bef9bc5c6 ("smb: smb2pdu.h: Avoid -Wflex-array-member-not-at-end
warnings") introduced tagged `struct create_context_hdr`. We want to
ensure that when new members need to be added to the flexible structure,
they are always included within this tagged struct.

So, we use `static_assert()` to ensure that the memory layout for
both the flexible structure and the tagged struct is the same after
any changes.

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
---

diff --git a/fs/smb/common/smb2pdu.h b/fs/smb/common/smb2pdu.h
index c3ee42188d25..c769f9dbc0b4 100644
--- a/fs/smb/common/smb2pdu.h
+++ b/fs/smb/common/smb2pdu.h
@@ -1216,6 +1216,8 @@ struct create_context {
 	);
 	__u8 Buffer[];
 } __packed;
+static_assert(offsetof(struct create_context, Buffer) == sizeof(struct create_context_hdr),
+	      "struct member likely outside of __struct_group()");
 
 struct smb2_create_req {
 	struct smb2_hdr hdr;