netdev - [PATCH] nexthop: Annotate struct nh_notifier_grp_info with __counted

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20231003232146.work.248-kees@kernel.org>
Date: Tue,  3 Oct 2023 16:21:47 -0700
From: Kees Cook <keescook@...omium.org>
To: David Ahern <dsahern@...nel.org>
Cc: Kees Cook <keescook@...omium.org>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	Nathan Chancellor <nathan@...nel.org>,
	Nick Desaulniers <ndesaulniers@...gle.com>,
	Tom Rix <trix@...hat.com>,
	netdev@...r.kernel.org,
	llvm@...ts.linux.dev,
	"Gustavo A. R. Silva" <gustavoars@...nel.org>,
	linux-kernel@...r.kernel.org,
	linux-hardening@...r.kernel.org
Subject: [PATCH] nexthop: Annotate struct nh_notifier_grp_info 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 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 nh_notifier_grp_info.

Cc: David Ahern <dsahern@...nel.org>
Cc: "David S. Miller" <davem@...emloft.net>
Cc: Eric Dumazet <edumazet@...gle.com>
Cc: Jakub Kicinski <kuba@...nel.org>
Cc: Paolo Abeni <pabeni@...hat.com>
Cc: Nathan Chancellor <nathan@...nel.org>
Cc: Nick Desaulniers <ndesaulniers@...gle.com>
Cc: Tom Rix <trix@...hat.com>
Cc: netdev@...r.kernel.org
Cc: llvm@...ts.linux.dev
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <keescook@...omium.org>
---
 include/net/nexthop.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/nexthop.h b/include/net/nexthop.h
index 2b12725de9c0..5dc4b4bba8a5 100644
--- a/include/net/nexthop.h
+++ b/include/net/nexthop.h
@@ -187,7 +187,7 @@ struct nh_notifier_grp_entry_info {
 struct nh_notifier_grp_info {
 	u16 num_nh;
 	bool is_fdb;
-	struct nh_notifier_grp_entry_info nh_entries[];
+	struct nh_notifier_grp_entry_info nh_entries[] __counted_by(num_nh);
 };
 
 struct nh_notifier_res_bucket_info {
-- 
2.34.1