Patch "ipvs: Update width of source for ip_vs_sync_conn_options" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ipvs: Update width of source for ip_vs_sync_conn_options

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ipvs-update-width-of-source-for-ip_vs_sync_conn_opti.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 872ec415a695cc98ca4b9a0ae010b7076866b816
Author: Simon Horman <horms@xxxxxxxxxx>
Date:   Mon Apr 17 17:10:45 2023 +0200

    ipvs: Update width of source for ip_vs_sync_conn_options
    
    [ Upstream commit e3478c68f6704638d08f437cbc552ca5970c151a ]
    
    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 <horms@xxxxxxxxxx>
    Reviewed-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
    Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index d609e957a3ec0..c02c3bb0fe091 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -549,8 +549,10 @@ 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 daab857c52a80..fc8db03d3efca 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++;