[PATCH RESEND] p2p: Limit P2P_DEVICE name to appropriate ifname size

[Benjamin Berg]

From: Benjamin Berg <bberg at redhat.com>

Otherwise the WPA_IF_P2P_DEVICE cannot be created. As this is not a
netdev device, it is acceptable if the name is not completely unique. As
such, simply insert a NUL byte at the appropriate place.

Signed-off-by: Benjamin Berg <bberg at redhat.com>
---
 wpa_supplicant/p2p_supplicant.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
index e94bffe52..17c25889c 100644
--- a/wpa_supplicant/p2p_supplicant.c
+++ b/wpa_supplicant/p2p_supplicant.c
@@ -3929,6 +3929,10 @@ int wpas_p2p_add_p2pdev_interface(struct wpa_supplicant *wpa_s,
 			  wpa_s->ifname);
 	if (os_snprintf_error(sizeof(ifname), ret))
 		return -1;
+	/* Cut length at the maximum size. Note that we don't need to ensure
+	 * collision free names here as the created interface is not a netdev.
+	 */
+	ifname[IFNAMSIZ-1] = '\0';
 	force_name[0] = '\0';
 	wpa_s->pending_interface_type = WPA_IF_P2P_DEVICE;
 	ret = wpa_drv_if_add(wpa_s, WPA_IF_P2P_DEVICE, ifname, NULL, NULL,
-- 
2.26.2