From 60b1af64eb35074a4f2d41cc1e503a7671e68963 Mon Sep 17 00:00:00 2001
From: Yi Zhang <yi.zhang@redhat.com>
Date: Thu, 20 Aug 2020 23:36:46 +0800
Subject: [PATCH 1/1] RDMA/rxe: Fix the parent sysfs read when the interface
Git-commit: 60b1af64eb35074a4f2d41cc1e503a7671e68963
Patch-mainline: v5.10-rc1
References: bsc#1111666
has 15 chars
'parent' sysfs reads will yield '\0' bytes when the interface name has 15
chars, and there will no "\n" output.
To reproduce, create one interface with 15 chars:
[root@test ~]# ip a s enp0s29u1u7u3c2
2: enp0s29u1u7u3c2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 1000
link/ether 02:21:28:57:47:17 brd ff:ff:ff:ff:ff:ff
inet6 fe80::ac41:338f:5bcd:c222/64 scope link noprefixroute
valid_lft forever preferred_lft forever
[root@test ~]# modprobe rdma_rxe
[root@test ~]# echo enp0s29u1u7u3c2 > /sys/module/rdma_rxe/parameters/add
[root@test ~]# cat /sys/class/infiniband/rxe0/parent
enp0s29u1u7u3c2[root@test ~]#
[root@test ~]# f="/sys/class/infiniband/rxe0/parent"
[root@test ~]# echo "$(<"$f")"
-bash: warning: command substitution: ignored null byte in input
enp0s29u1u7u3c2
Use scnprintf and PAGE_SIZE to fill the sysfs output buffer.
Cc: stable@vger.kernel.org
Fixes: 8700e3e7c485 ("Soft RoCE driver")
Link: https://lore.kernel.org/r/20200820153646.31316-1-yi.zhang@redhat.com
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Yi Zhang <yi.zhang@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
---
drivers/infiniband/sw/rxe/rxe_verbs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
index bb61e534e468..756980f79951 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -1056,7 +1056,7 @@ static ssize_t parent_show(struct device *device,
struct rxe_dev *rxe = container_of(device, struct rxe_dev,
ib_dev.dev);
- return snprintf(buf, 16, "%s\n", rxe_parent_name(rxe, 1));
+ return scnprintf(buf, PAGE_SIZE, "%s\n", rxe_parent_name(rxe, 1));
}
static DEVICE_ATTR_RO(parent);
--
2.29.2.405.gfdfcad78fd04