[PATCH 5.4 091/108] RDMA/cma: Fix arguments order in net device validation

From: Greg Kroah-Hartman
Date: Tue Sep 13 2022 - 11:06:06 EST


From: Michael Guralnik <michaelgur@xxxxxxxxxx>

[ Upstream commit 27cfde795a96aef1e859a5480489944b95421e46 ]

Fix the order of source and destination addresses when resolving the
route between server and client to validate use of correct net device.

The reverse order we had so far didn't actually validate the net device
as the server would try to resolve the route to itself, thus always
getting the server's net device.

The issue was discovered when running cm applications on a single host
between 2 interfaces with same subnet and source based routing rules.
When resolving the reverse route the source based route rules were
ignored.

Fixes: f887f2ac87c2 ("IB/cma: Validate routing of incoming requests")
Link: https://lore.kernel.org/r/1c1ec2277a131d277ebcceec987fd338d35b775f.1661251872.git.leonro@xxxxxxxxxx
Signed-off-by: Michael Guralnik <michaelgur@xxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/core/cma.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index de7df5ab06f3b..cf174aa7fe25b 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -1719,8 +1719,8 @@ cma_ib_id_from_event(struct ib_cm_id *cm_id,
}

if (!validate_net_dev(*net_dev,
- (struct sockaddr *)&req->listen_addr_storage,
- (struct sockaddr *)&req->src_addr_storage)) {
+ (struct sockaddr *)&req->src_addr_storage,
+ (struct sockaddr *)&req->listen_addr_storage)) {
id_priv = ERR_PTR(-EHOSTUNREACH);
goto err;
}
--
2.35.1