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From: Kees Cook <keescook@chromium.org>
To: Christine Caulfield <ccaulfie@redhat.com>
Cc: Kees Cook <keescook@chromium.org>,
	David Teigland <teigland@redhat.com>,
	cluster-devel@redhat.com,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: [PATCH] dlm: Split memcpy() of struct dlm_message flexible array
Date: Fri, 23 Sep 2022 20:52:26 -0700	[thread overview]
Message-ID: <20220924035226.3359297-1-keescook@chromium.org> (raw)

To work around a misbehavior of the compiler's ability to see into
composite flexible array structs (as detailed in the coming memcpy()
hardening series[1]), split the memcpy() of the header and the payload
so no false positive run-time overflow warning will be generated.

[1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org/

Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: cluster-devel@redhat.com
Reported-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 fs/dlm/requestqueue.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/dlm/requestqueue.c b/fs/dlm/requestqueue.c
index 036a9a0078f6..63f45c3c53a2 100644
--- a/fs/dlm/requestqueue.c
+++ b/fs/dlm/requestqueue.c
@@ -44,7 +44,8 @@ void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_message *ms)
 
 	e->recover_seq = ls->ls_recover_seq & 0xFFFFFFFF;
 	e->nodeid = nodeid;
-	memcpy(&e->request, ms, le16_to_cpu(ms->m_header.h_length));
+	e->request = *ms;
+	memcpy(&e->request.m_extra, ms->m_extra, length);
 
 	atomic_inc(&ls->ls_requestqueue_cnt);
 	mutex_lock(&ls->ls_requestqueue_mutex);
-- 
2.34.1


WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org>
To: cluster-devel.redhat.com
Subject: [Cluster-devel] [PATCH] dlm: Split memcpy() of struct dlm_message flexible array
Date: Fri, 23 Sep 2022 20:52:26 -0700	[thread overview]
Message-ID: <20220924035226.3359297-1-keescook@chromium.org> (raw)

To work around a misbehavior of the compiler's ability to see into
composite flexible array structs (as detailed in the coming memcpy()
hardening series[1]), split the memcpy() of the header and the payload
so no false positive run-time overflow warning will be generated.

[1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook at chromium.org/

Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: cluster-devel at redhat.com
Reported-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 fs/dlm/requestqueue.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/dlm/requestqueue.c b/fs/dlm/requestqueue.c
index 036a9a0078f6..63f45c3c53a2 100644
--- a/fs/dlm/requestqueue.c
+++ b/fs/dlm/requestqueue.c
@@ -44,7 +44,8 @@ void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_message *ms)
 
 	e->recover_seq = ls->ls_recover_seq & 0xFFFFFFFF;
 	e->nodeid = nodeid;
-	memcpy(&e->request, ms, le16_to_cpu(ms->m_header.h_length));
+	e->request = *ms;
+	memcpy(&e->request.m_extra, ms->m_extra, length);
 
 	atomic_inc(&ls->ls_requestqueue_cnt);
 	mutex_lock(&ls->ls_requestqueue_mutex);
-- 
2.34.1


             reply	other threads:[~2022-09-24  3:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-24  3:52 Kees Cook [this message]
2022-09-24  3:52 ` [Cluster-devel] [PATCH] dlm: Split memcpy() of struct dlm_message flexible array Kees Cook
2022-09-24  4:03 ` Gustavo A. R. Silva
2022-09-24  4:03   ` [Cluster-devel] " Gustavo A. R. Silva

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