ipvs: Update width of source for ip_vs_sync_conn_options

[ Upstream commit e3478c68f6 ]

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@kernel.org>
Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Simon Horman 2023-04-17 17:10:45 +02:00 committed by Greg Kroah-Hartman
parent fab766c8a1
commit 75481fa7aa
2 changed files with 5 additions and 3 deletions

View file

@ -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;

View file

@ -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++;