[PATCH] net/mana: use %m for fscanf to read mac address

[longli]

From: Long Li <lon...@microsoft.com>

Use %m through fscanf to allocate mac dynamically is safer than using
mac[20], this guarantees there is no overflow on mac[].

Signed-off-by: Long Li <lon...@microsoft.com>
---
 drivers/net/mana/mana.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/mana/mana.c b/drivers/net/mana/mana.c
index f1fdcf426a..28d8f5b23e 100644
--- a/drivers/net/mana/mana.c
+++ b/drivers/net/mana/mana.c
@@ -914,7 +914,6 @@ get_port_mac(struct ibv_device *device, unsigned int port,
        DIR *dir;
        struct dirent *dent;
        unsigned int dev_port;
-       char mac[20];
 
        MANA_MKSTR(path, "%s/device/net", device->ibdev_path);
 
@@ -924,6 +923,7 @@ get_port_mac(struct ibv_device *device, unsigned int port,
 
        while ((dent = readdir(dir))) {
                char *name = dent->d_name;
+               char *mac = NULL;
 
                MANA_MKSTR(port_path, "%s/%s/dev_port", path, name);
 
@@ -951,7 +951,7 @@ get_port_mac(struct ibv_device *device, unsigned int port,
                        if (!file)
                                continue;
 
-                       ret = fscanf(file, "%s", mac);
+                       ret = fscanf(file, "%ms", &mac);
                        fclose(file);
 
                        if (ret < 0)
@@ -960,6 +960,8 @@ get_port_mac(struct ibv_device *device, unsigned int port,
                        ret = rte_ether_unformat_addr(mac, addr);
                        if (ret)
                                DRV_LOG(ERR, "unrecognized mac addr %s", mac);
+
+                       free(mac);
                        break;
                }
        }
-- 
2.34.1