Re: [PATCH] drivers/net/wireless/ipw2x00: use strlcpy instead of strncpy

[Joe Perches <joe@perches.com>]

On Mon, 2013-01-07 at 10:49 +0800, Chen Gang wrote:
>   but I think the original author intended to use escaped instead of ssid
>     DECLARE_SSID_BUF(ssid)  (line 5525, 5737)
>     use ssid to print debug information directly
>       (such as: line 5530..5535, 5545..5549, 5745..5749, ...)
>     when need print additional information, use escaped
>       (line 5559..5569, 5773..5782, 5791..5799)
> 
>   so, I still suggest:
>     only fix the bug (use strlcpy instead of strncpy)
>     and not touch original features which orignal author intended using.

More likely John Linville just missed the conversions.
4+ years ago.

commit 9387b7caf3049168fc97a8a9111af8fe2143af18
Author: John W. Linville <linville@tuxdriver.com>
Date:   Tue Sep 30 20:59:05 2008 -0400

    wireless: use individual buffers for printing ssid values
  
    Also change escape_ssid to print_ssid to match print_mac semantics.
    
    Signed-off-by: John W. Linville <linville@tuxdriver.com>

Maybe these days this should be another vsprintf %p extension
like %pM when the DECLARE_MAC_BUF/print_mac uses were converted.

(or maybe extend %ph for ssids with %*phs, length, array)

But if and until then, I suggest this instead:

 drivers/net/wireless/ipw2x00/ipw2200.c | 38 ++++++++++++++--------------------
 1 file changed, 15 insertions(+), 23 deletions(-)

diff --git a/drivers/net/wireless/ipw2x00/ipw2200.c b/drivers/net/wireless/ipw2x00/ipw2200.c
index 844f201..3dc6a92 100644
--- a/drivers/net/wireless/ipw2x00/ipw2200.c
+++ b/drivers/net/wireless/ipw2x00/ipw2200.c
@@ -5556,15 +5556,12 @@ static int ipw_find_adhoc_network(struct ipw_priv *priv,
 		    ((network->ssid_len != priv->essid_len) ||
 		     memcmp(network->ssid, priv->essid,
 			    min(network->ssid_len, priv->essid_len)))) {
-			char escaped[IW_ESSID_MAX_SIZE * 2 + 1];
+			DECLARE_SSID_BUF(escaped);
 
-			strncpy(escaped,
-				print_ssid(ssid, network->ssid,
-					   network->ssid_len),
-				sizeof(escaped));
-			IPW_DEBUG_MERGE("Network '%s (%pM)' excluded "
-					"because of ESSID mismatch: '%s'.\n",
-					escaped, network->bssid,
+			IPW_DEBUG_MERGE("Network '%s (%pM)' excluded because of ESSID mismatch: '%s'\n",
+					print_ssid(escaped, network->ssid,
+						   network->ssid_len),
+					network->bssid,
 					print_ssid(ssid, priv->essid,
 						   priv->essid_len));
 			return 0;
@@ -5770,14 +5767,11 @@ static int ipw_best_network(struct ipw_priv *priv,
 		    ((network->ssid_len != priv->essid_len) ||
 		     memcmp(network->ssid, priv->essid,
 			    min(network->ssid_len, priv->essid_len)))) {
-			char escaped[IW_ESSID_MAX_SIZE * 2 + 1];
-			strncpy(escaped,
-				print_ssid(ssid, network->ssid,
-					   network->ssid_len),
-				sizeof(escaped));
-			IPW_DEBUG_ASSOC("Network '%s (%pM)' excluded "
-					"because of ESSID mismatch: '%s'.\n",
-					escaped, network->bssid,
+			DECLARE_SSID_BUF(escaped);
+			IPW_DEBUG_ASSOC("Network '%s (%pM)' excluded because of ESSID mismatch: '%s'\n",
+					print_ssid(escaped, network->ssid,
+						   network->ssid_len),
+					network->bssid,
 					print_ssid(ssid, priv->essid,
 						   priv->essid_len));
 			return 0;
@@ -5787,13 +5781,11 @@ static int ipw_best_network(struct ipw_priv *priv,
 	/* If the old network rate is better than this one, don't bother
 	 * testing everything else. */
 	if (match->network && match->network->stats.rssi > network->stats.rssi) {
-		char escaped[IW_ESSID_MAX_SIZE * 2 + 1];
-		strncpy(escaped,
-			print_ssid(ssid, network->ssid, network->ssid_len),
-			sizeof(escaped));
-		IPW_DEBUG_ASSOC("Network '%s (%pM)' excluded because "
-				"'%s (%pM)' has a stronger signal.\n",
-				escaped, network->bssid,
+		DECLARE_SSID_BUF(escaped);
+		IPW_DEBUG_ASSOC("Network '%s (%pM)' excluded because '%s (%pM)' has a stronger signal\n",
+				print_ssid(escaped, network->ssid,
+					   network->ssid_len),
+				network->bssid,
 				print_ssid(ssid, match->network->ssid,
 					   match->network->ssid_len),
 				match->network->bssid);