From c0c64aac4916a2592bd174547b279a408368dd31 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Fri, 15 Sep 2023 13:14:27 -0700
Subject: [PATCH] nfs41: Annotate struct nfs4_file_layout_dsaddr 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 nfs4_file_layout_dsaddr.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-nfs@vger.kernel.org
Link: https://lore.kernel.org/r/20230915201427.never.771-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
fs/nfs/filelayout/filelayout.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nfs/filelayout/filelayout.h b/fs/nfs/filelayout/filelayout.h
index aed0748fd6ec..c7bb5da93307 100644
--- a/fs/nfs/filelayout/filelayout.h
+++ b/fs/nfs/filelayout/filelayout.h
@@ -51,7 +51,7 @@ struct nfs4_file_layout_dsaddr {
u32 stripe_count;
u8 *stripe_indices;
u32 ds_num;
- struct nfs4_pnfs_ds *ds_list[];
+ struct nfs4_pnfs_ds *ds_list[] __counted_by(ds_num);
};
struct nfs4_filelayout_segment {