From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Subject: [PATCH nf-next 1/4] ipvs: Update width of source for ip_vs_sync_con_options Date: Mon, 10 Apr 2023 11:42:35 +0200 Message-ID: <20230409-ipvs-cleanup-v1-1-98cdc242feb0@kernel.org> References: <20230409-ipvs-cleanup-v1-0-98cdc242feb0@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1681119775; bh=qATQ34H7t/140BYO5XpIrp+uhhYgzRmHCSvABBsP+MI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=lnBmAS4vUtio7WSZOM1tLmliF8G1CrqwtndUF+ToVoQiC2CLHHYFpyc7wphXN+uZT Brft6s2w7m4zWbgcXH83iUqFXv78HeDasibEgex1G+f+mXQQI0rl7mSiuAndyj9J5j 5QUHOriA5KL5OLZlKjGH8px1RDbJCZOhxOc2Qvj9y1WNIVjcg1nY5hFSEWNqCGR9ht PIHI1VfF1RhIqCFvSiCT+Vd6+aCgSGMUWXzDs9fsb6JjroHPC8frdbkX+lhyopngKB 4gC24OTE8IGrYs/3fwyEbLdexbCqQ005TitTw8wtwbsDyx41qkNj2bdIXGt0YZD8in psjwlVeWFMBrA== In-Reply-To: <20230409-ipvs-cleanup-v1-0-98cdc242feb0@kernel.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: Julian Anastasov Cc: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , netdev@vger.kernel.org, "David S. Miller" , David Ahern , Eric Dumazet , Jakub Kicinski , Paolo Abeni , lvs-devel@vger.kernel.org, linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org In ip_vs_sync_conn_v0() copy is made to struct ip_vs_sync_conn_options. That structure looks like this: struct ip_vs_sync_conn_options { struct ip_vs_seq in_seq; struct ip_vs_seq out_seq; }; The source of the copy is the in_seq field of struct ip_vs_conn. Whose type is struct ip_vs_seq. Thus we can see that the source - is not as wide as the amount of data copied, which is the width of struct ip_vs_sync_conn_option. The copy is safe because the next field in is another struct ip_vs_seq. Make use of struct_group() to annotate this. Flagged by gcc-13 as: In file included from ./include/linux/string.h:254, from ./include/linux/bitmap.h:11, from ./include/linux/cpumask.h:12, from ./arch/x86/include/asm/paravirt.h:17, from ./arch/x86/include/asm/cpuid.h:62, from ./arch/x86/include/asm/processor.h:19, from ./arch/x86/include/asm/timex.h:5, from ./include/linux/timex.h:67, from ./include/linux/time32.h:13, from ./include/linux/time.h:60, from ./include/linux/stat.h:19, from ./include/linux/module.h:13, from net/netfilter/ipvs/ip_vs_sync.c:38: In function 'fortify_memcpy_chk', inlined from 'ip_vs_sync_conn_v0' at net/netfilter/ipvs/ip_vs_sync.c:606:3: ./include/linux/fortify-string.h:529:25: error: call to '__read_overflow2_field' declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Werror=attribute-warning] 529 | __read_overflow2_field(q_size_field, size); | Compile tested only. Signed-off-by: Simon Horman --- include/net/ip_vs.h | 6 ++++-- net/netfilter/ipvs/ip_vs_sync.c | 2 +- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index 6d71a5ff52df..e20f1f92066d 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -630,8 +630,10 @@ struct ip_vs_conn { */ struct ip_vs_app *app; /* bound ip_vs_app object */ void *app_data; /* Application private data */ - struct ip_vs_seq in_seq; /* incoming seq. struct */ - struct ip_vs_seq out_seq; /* outgoing seq. struct */ + struct_group(sync_conn_opt, + struct ip_vs_seq in_seq; /* incoming seq. struct */ + struct ip_vs_seq out_seq; /* outgoing seq. struct */ + ); const struct ip_vs_pe *pe; char *pe_data; diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c index 4963fec815da..d4fe7bb4f853 100644 --- a/net/netfilter/ipvs/ip_vs_sync.c +++ b/net/netfilter/ipvs/ip_vs_sync.c @@ -603,7 +603,7 @@ static void ip_vs_sync_conn_v0(struct netns_ipvs *ipvs, struct ip_vs_conn *cp, if (cp->flags & IP_VS_CONN_F_SEQ_MASK) { struct ip_vs_sync_conn_options *opt = (struct ip_vs_sync_conn_options *)&s[1]; - memcpy(opt, &cp->in_seq, sizeof(*opt)); + memcpy(opt, &cp->sync_conn_opt, sizeof(*opt)); } m->nr_conns++; -- 2.30.2