On some kernels the string attributes within Netlink
reply messages might be not padded with zeroes (in cases
when string length is aligned with 4-byte boundary).
This caused wrong physical port names recognition and
mlx5 PMD load failures.
Fixes: 30a86157f6d5 ("net/mlx5: support PF representor")
Cc: sta...@dpdk.org
Signed-off-by: Viacheslav Ovsiienko <viachesl...@nvidia.com>
---
drivers/common/mlx5/linux/mlx5_nl.c | 22 +++++++++++++++++++++-
1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/drivers/common/mlx5/linux/mlx5_nl.c
b/drivers/common/mlx5/linux/mlx5_nl.c
index f0d04f9473..3f1912d078 100644
--- a/drivers/common/mlx5/linux/mlx5_nl.c
+++ b/drivers/common/mlx5/linux/mlx5_nl.c
@@ -33,6 +33,8 @@
#define MLX5_SEND_BUF_SIZE 32768
/* Receive buffer size for the Netlink socket */
#define MLX5_RECV_BUF_SIZE 32768
+/* Maximal physical port name length. */
+#define MLX5_PHYS_PORT_NAME_MAX 128
/** Parameters of VLAN devices created by driver. */
#define MLX5_VMWA_VLAN_DEVICE_PFX "evmlx"
@@ -1191,6 +1193,7 @@ mlx5_nl_switch_info_cb(struct nlmsghdr *nh, void *arg)
size_t off = NLMSG_LENGTH(sizeof(struct ifinfomsg));
bool switch_id_set = false;
bool num_vf_set = false;
+ int len;
if (nh->nlmsg_type != RTM_NEWLINK)
goto error;
@@ -1206,7 +1209,24 @@ mlx5_nl_switch_info_cb(struct nlmsghdr *nh, void *arg)
num_vf_set = true;
break;
case IFLA_PHYS_PORT_NAME:
- mlx5_translate_port_name((char *)payload, &info);
+ len = RTA_PAYLOAD(ra);
+ /* Some kernels do not pad attributes with zero. */
+ if (len > 0 && len < MLX5_PHYS_PORT_NAME_MAX) {
+ char name[MLX5_PHYS_PORT_NAME_MAX];
+
+ /*
+ * We can't just patch the message with padding
+ * zero - it might corrupt the following items
+ * in the message, we have to copy the string
+ * by attribute length and pad the copied one.
+ */
+ memcpy(name, payload, len);
+ name[len] = 0;
+ mlx5_translate_port_name(name, &info);
+ } else {
+ info.name_type =
+ MLX5_PHYS_PORT_NAME_TYPE_UNKNOWN;
+ }
break;
case IFLA_PHYS_SWITCH_ID:
info.switch_id = 0;
--
2.18.1
