i40e: Use scnprintf() for avoiding potential buffer overflow

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index ea7395b..5d807c8 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -14486,29 +14486,29 @@ static void i40e_print_features(struct i40e_pf *pf)
 
        i = snprintf(buf, INFO_STRING_LEN, "Features: PF-id[%d]", hw->pf_id);
 #ifdef CONFIG_PCI_IOV
-       i += snprintf(&buf[i], REMAIN(i), " VFs: %d", pf->num_req_vfs);
+       i += scnprintf(&buf[i], REMAIN(i), " VFs: %d", pf->num_req_vfs);
 #endif
-       i += snprintf(&buf[i], REMAIN(i), " VSIs: %d QP: %d",
+       i += scnprintf(&buf[i], REMAIN(i), " VSIs: %d QP: %d",
                      pf->hw.func_caps.num_vsis,
                      pf->vsi[pf->lan_vsi]->num_queue_pairs);
        if (pf->flags & I40E_FLAG_RSS_ENABLED)
-               i += snprintf(&buf[i], REMAIN(i), " RSS");
+               i += scnprintf(&buf[i], REMAIN(i), " RSS");
        if (pf->flags & I40E_FLAG_FD_ATR_ENABLED)
-               i += snprintf(&buf[i], REMAIN(i), " FD_ATR");
+               i += scnprintf(&buf[i], REMAIN(i), " FD_ATR");
        if (pf->flags & I40E_FLAG_FD_SB_ENABLED) {
-               i += snprintf(&buf[i], REMAIN(i), " FD_SB");
-               i += snprintf(&buf[i], REMAIN(i), " NTUPLE");
+               i += scnprintf(&buf[i], REMAIN(i), " FD_SB");
+               i += scnprintf(&buf[i], REMAIN(i), " NTUPLE");
        }
        if (pf->flags & I40E_FLAG_DCB_CAPABLE)
-               i += snprintf(&buf[i], REMAIN(i), " DCB");
-       i += snprintf(&buf[i], REMAIN(i), " VxLAN");
-       i += snprintf(&buf[i], REMAIN(i), " Geneve");
+               i += scnprintf(&buf[i], REMAIN(i), " DCB");
+       i += scnprintf(&buf[i], REMAIN(i), " VxLAN");
+       i += scnprintf(&buf[i], REMAIN(i), " Geneve");
        if (pf->flags & I40E_FLAG_PTP)
-               i += snprintf(&buf[i], REMAIN(i), " PTP");
+               i += scnprintf(&buf[i], REMAIN(i), " PTP");
        if (pf->flags & I40E_FLAG_VEB_MODE_ENABLED)
-               i += snprintf(&buf[i], REMAIN(i), " VEB");
+               i += scnprintf(&buf[i], REMAIN(i), " VEB");
        else
-               i += snprintf(&buf[i], REMAIN(i), " VEPA");
+               i += scnprintf(&buf[i], REMAIN(i), " VEPA");
 
        dev_info(&pf->pdev->dev, "%s\n", buf);
        kfree(buf);