diff --git a/package/network/services/hostapd/patches/060-P2P-Fix-a-corner-case-in-peer-addition-based-on-PD-R.patch b/package/network/services/hostapd/patches/060-P2P-Fix-a-corner-case-in-peer-addition-based-on-PD-R.patch new file mode 100644 index 00000000000..1202ff3725b --- /dev/null +++ b/package/network/services/hostapd/patches/060-P2P-Fix-a-corner-case-in-peer-addition-based-on-PD-R.patch @@ -0,0 +1,45 @@ +From 8460e3230988ef2ec13ce6b69b687e941f6cdb32 Mon Sep 17 00:00:00 2001 +From: Jouni Malinen +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 +--- + src/p2p/p2p_pd.c | 12 +++++------- + 1 file changed, 5 insertions(+), 7 deletions(-) + +--- a/src/p2p/p2p_pd.c ++++ b/src/p2p/p2p_pd.c +@@ -595,14 +595,12 @@ void p2p_process_prov_disc_req(struct p2 + 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);