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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id q5sm3971112pjo.7.2021.07.27.14.16.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Jul 2021 14:16:50 -0700 (PDT) From: Kees Cook To: linux-hardening@vger.kernel.org Cc: Kees Cook , "Gustavo A. R. Silva" , Keith Packard , Greg Kroah-Hartman , Andrew Morton , linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-staging@lists.linux.dev, linux-block@vger.kernel.org, linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com Subject: [PATCH 57/64] netfilter: conntrack: Use struct_group() to zero struct nf_conn Date: Tue, 27 Jul 2021 13:58:48 -0700 Message-Id: <20210727205855.411487-58-keescook@chromium.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210727205855.411487-1-keescook@chromium.org> References: <20210727205855.411487-1-keescook@chromium.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2310; h=from:subject; bh=s7DyCBPDaCq4d9JSsWLJ8+EongifST6biZFyx2UX6q8=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBhAHONWBiPiNzo/t8OW3Ns6kZ2l8riv+DL/V9XSJtK Xd5HzDuJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCYQBzjQAKCRCJcvTf3G3AJsz7D/ 42pKBLJYcyHNJwO4YohbAAmhcoXAY8bmybN4HQPzp0zeFLNZqc2Mjb4rl3swZnOVaOVIL3tdvOiDgh i8NP+ht5TIItplmx8kwQTDPnNvvzlkJ82eWDHbvlZo9L/KkG3tB6q0ZoB5wyDwJ/WtKkX+tNlUGMRP OkokNS0HmTNz9ICaj7b7j9osXWGi57NUaXBtDDH/qH8MsT0lOJRU2Z4gVtlmQ4R2LKaBHTKEt6BHyM 60WMlTbzjKwmlSHB2aAoSUxJeN+xflQRuXnp9Z6gejpjykNWv/FHyosJTO5fvOqyY7fnbG5IP18fDs 13RH/EqMrXXtaC08nbTDiHc7xZZd07xjYusHaAykXGZ1M93N5Yyv4Ki7pupKpuLMhmBe3mMJ6R9V/9 uGqhRuL79KG+FrjRZBGe6WhgC/PPRmNIQiKGNNqoLP4kHNzZGslITSZJ/dhW1VxfIJC4CSyVjW5cgL prwEVJwtrbEMjXtHxTTF6YTc9ktMv2sS2o53nA9MrdPsxA9UV/yGCIxScUw8rTkzsu8Mk49on1WZf9 QEGh/Zy6T4S+lmbbiyXk3M1IAIDUYvs9WGAIYNlGzCMyk8XCDW9FUvuYcOQEU7XduJJ/wAhIG6MGew +7Dpxb4bbGybSLftmpNT3cPqKZ0HD+6F3Nbr82t0S06MwdOE0b2kHOrmjCYg== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Replace the empty __nfct_init_offset member with a struct_group() to mark the region of struct nf_conn that should be initialized to zero, allowing memset() to correctly reason about the size of the write. Signed-off-by: Kees Cook --- include/net/netfilter/nf_conntrack.h | 20 ++++++++++---------- net/netfilter/nf_conntrack_core.c | 4 +--- 2 files changed, 11 insertions(+), 13 deletions(-) diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index cc663c68ddc4..51004fce2937 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -101,24 +101,24 @@ struct nf_conn { struct hlist_node nat_bysource; #endif /* all members below initialized via memset */ - struct { } __nfct_init_offset; - - /* If we were expected by an expectation, this will be it */ - struct nf_conn *master; + struct_group(init, + /* If we were expected by an expectation, this will be it */ + struct nf_conn *master; #if defined(CONFIG_NF_CONNTRACK_MARK) - u_int32_t mark; + u_int32_t mark; #endif #ifdef CONFIG_NF_CONNTRACK_SECMARK - u_int32_t secmark; + u_int32_t secmark; #endif - /* Extensions */ - struct nf_ct_ext *ext; + /* Extensions */ + struct nf_ct_ext *ext; - /* Storage reserved for other modules, must be the last member */ - union nf_conntrack_proto proto; + /* Storage reserved for other modules, must be the last member */ + union nf_conntrack_proto proto; + ); }; static inline struct nf_conn * diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 5c03e5106751..b05eb64ec788 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1527,9 +1527,7 @@ __nf_conntrack_alloc(struct net *net, ct->status = 0; ct->timeout = 0; write_pnet(&ct->ct_net, net); - memset(&ct->__nfct_init_offset, 0, - offsetof(struct nf_conn, proto) - - offsetof(struct nf_conn, __nfct_init_offset)); + memset(&ct->init, 0, sizeof(ct->init)); nf_ct_zone_add(ct, zone);