The change of sizeof(struct smc_diag_linkinfo) by commit 79d39fc503b4
("net/smc: Add netlink net namespace support") introduced an ABI
regression: since struct smc_diag_lgrinfo contains an object of
type "struct smc_diag_linkinfo", offset of all subsequent members
of struct smc_diag_lgrinfo was changed by that change.
As result, applications compiled with the old version
of struct smc_diag_linkinfo will receive garbage in
struct smc_diag_lgrinfo.role if the kernel implements
this new version of struct smc_diag_linkinfo.
Fix this regression by reverting the part of commit 79d39fc503b4 that
changes struct smc_diag_linkinfo. After all, there is SMC_GEN_NETLINK
interface which is good enough, so there is probably no need to touch
the smc_diag ABI in the first place.
Fixes: 79d39fc503b4 ("net/smc: Add netlink net namespace support")
Signed-off-by: Dmitry V. Levin <ldv@xxxxxxxxxxxx>
---
include/uapi/linux/smc_diag.h | 11 +++++------
net/smc/smc_diag.c | 2 --
2 files changed, 5 insertions(+), 8 deletions(-)
diff --git a/include/uapi/linux/smc_diag.h b/include/uapi/linux/smc_diag.h
index c7008d87f1a4..8cb3a6fef553 100644
--- a/include/uapi/linux/smc_diag.h
+++ b/include/uapi/linux/smc_diag.h
@@ -84,12 +84,11 @@ struct smc_diag_conninfo {
/* SMC_DIAG_LINKINFO */
struct smc_diag_linkinfo {
- __u8 link_id; /* link identifier */
- __u8 ibname[IB_DEVICE_NAME_MAX]; /* name of the RDMA device */
- __u8 ibport; /* RDMA device port number */
- __u8 gid[40]; /* local GID */
- __u8 peer_gid[40]; /* peer GID */
- __aligned_u64 net_cookie; /* RDMA device net namespace */
+ __u8 link_id; /* link identifier */
+ __u8 ibname[IB_DEVICE_NAME_MAX]; /* name of the RDMA device */
+ __u8 ibport; /* RDMA device port number */
+ __u8 gid[40]; /* local GID */
+ __u8 peer_gid[40]; /* peer GID */
};
struct smc_diag_lgrinfo {
diff --git a/net/smc/smc_diag.c b/net/smc/smc_diag.c
index b8898c787d23..1fca2f90a9c7 100644
--- a/net/smc/smc_diag.c
+++ b/net/smc/smc_diag.c
@@ -146,13 +146,11 @@ static int __smc_diag_dump(struct sock *sk, struct sk_buff *skb,
(req->diag_ext & (1 << (SMC_DIAG_LGRINFO - 1))) &&
!list_empty(&smc->conn.lgr->list)) {
struct smc_link *link = smc->conn.lnk;
- struct net *net = read_pnet(&link->smcibdev->ibdev->coredev.rdma_net);
struct smc_diag_lgrinfo linfo = {
.role = smc->conn.lgr->role,
.lnk[0].ibport = link->ibport,
.lnk[0].link_id = link->link_id,
- .lnk[0].net_cookie = net->net_cookie,
};
memcpy(linfo.lnk[0].ibname,
--
ldv
