See <https://w1.fi/security/2021-1/wpa_supplicant-p2p-provision-discovery-processing-vulnerability.txt>. * gnu/packages/patches/wpa-supplicant-CVE-2021-27803.patch: New patch. * gnu/local.mk (dist_patch_DATA): Register it. * gnu/packages/admin.scm (wpa-supplicant-minimal, hostapd): Apply it.
		
			
				
	
	
		
			50 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
From 8460e3230988ef2ec13ce6b69b687e941f6cdb32 Mon Sep 17 00:00:00 2001
 | 
						|
From: Jouni Malinen <jouni@codeaurora.org>
 | 
						|
Date: Tue, 8 Dec 2020 23:52:50 +0200
 | 
						|
Subject: [PATCH] P2P: Fix a corner case in peer addition based on PD Request
 | 
						|
 | 
						|
p2p_add_device() may remove the oldest entry if there is no room in the
 | 
						|
peer table for a new peer. This would result in any pointer to that
 | 
						|
removed entry becoming stale. A corner case with an invalid PD Request
 | 
						|
frame could result in such a case ending up using (read+write) freed
 | 
						|
memory. This could only by triggered when the peer table has reached its
 | 
						|
maximum size and the PD Request frame is received from the P2P Device
 | 
						|
Address of the oldest remaining entry and the frame has incorrect P2P
 | 
						|
Device Address in the payload.
 | 
						|
 | 
						|
Fix this by fetching the dev pointer again after having called
 | 
						|
p2p_add_device() so that the stale pointer cannot be used.
 | 
						|
 | 
						|
Fixes: 17bef1e97a50 ("P2P: Add peer entry based on Provision Discovery Request")
 | 
						|
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
 | 
						|
---
 | 
						|
 src/p2p/p2p_pd.c | 12 +++++-------
 | 
						|
 1 file changed, 5 insertions(+), 7 deletions(-)
 | 
						|
 | 
						|
diff --git a/src/p2p/p2p_pd.c b/src/p2p/p2p_pd.c
 | 
						|
index 3994ec03f86b..05fd593494ef 100644
 | 
						|
--- a/src/p2p/p2p_pd.c
 | 
						|
+++ b/src/p2p/p2p_pd.c
 | 
						|
@@ -595,14 +595,12 @@ void p2p_process_prov_disc_req(struct p2p_data *p2p, const u8 *sa,
 | 
						|
 			goto out;
 | 
						|
 		}
 | 
						|
 
 | 
						|
+		dev = p2p_get_device(p2p, sa);
 | 
						|
 		if (!dev) {
 | 
						|
-			dev = p2p_get_device(p2p, sa);
 | 
						|
-			if (!dev) {
 | 
						|
-				p2p_dbg(p2p,
 | 
						|
-					"Provision Discovery device not found "
 | 
						|
-					MACSTR, MAC2STR(sa));
 | 
						|
-				goto out;
 | 
						|
-			}
 | 
						|
+			p2p_dbg(p2p,
 | 
						|
+				"Provision Discovery device not found "
 | 
						|
+				MACSTR, MAC2STR(sa));
 | 
						|
+			goto out;
 | 
						|
 		}
 | 
						|
 	} else if (msg.wfd_subelems) {
 | 
						|
 		wpabuf_free(dev->info.wfd_subelems);
 | 
						|
-- 
 | 
						|
2.25.1
 | 
						|
 |