net/smc: Make sure the link_id is unique

[ Upstream commit cf4f5530bb55ef7d5a91036b26676643b80b1616 ]

The link_id is supposed to be unique, but smcr_next_link_id() doesn't
skip the used link_id as expected. So the patch fixes this.

Fixes: 026c381fb477 ("net/smc: introduce link_idx for link group array")
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index d220674..d672c0f 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -665,13 +665,14 @@ static u8 smcr_next_link_id(struct smc_link_group *lgr)
        int i;
 
        while (1) {
+again:
                link_id = ++lgr->next_link_id;
                if (!link_id)   /* skip zero as link_id */
                        link_id = ++lgr->next_link_id;
                for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
                        if (smc_link_usable(&lgr->lnk[i]) &&
                            lgr->lnk[i].link_id == link_id)
-                               continue;
+                               goto again;
                }
                break;
        }