lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20211004125030.337411814@linuxfoundation.org>
Date:   Mon,  4 Oct 2021 14:52:30 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Johannes Berg <johannes.berg@...el.com>
Subject: [PATCH 5.4 10/56] mac80211: fix use-after-free in CCMP/GCMP RX

From: Johannes Berg <johannes.berg@...el.com>

commit 94513069eb549737bcfc3d988d6ed4da948a2de8 upstream.

When PN checking is done in mac80211, for fragmentation we need
to copy the PN to the RX struct so we can later use it to do a
comparison, since commit bf30ca922a0c ("mac80211: check defrag
PN against current frame").

Unfortunately, in that commit I used the 'hdr' variable without
it being necessarily valid, so use-after-free could occur if it
was necessary to reallocate (parts of) the frame.

Fix this by reloading the variable after the code that results
in the reallocations, if any.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=214401.

Cc: stable@...r.kernel.org
Fixes: bf30ca922a0c ("mac80211: check defrag PN against current frame")
Link: https://lore.kernel.org/r/20210927115838.12b9ac6bb233.I1d066acd5408a662c3b6e828122cd314fcb28cdb@changeid
Signed-off-by: Johannes Berg <johannes.berg@...el.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 net/mac80211/wpa.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -520,6 +520,9 @@ ieee80211_crypto_ccmp_decrypt(struct iee
 			return RX_DROP_UNUSABLE;
 	}
 
+	/* reload hdr - skb might have been reallocated */
+	hdr = (void *)rx->skb->data;
+
 	data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 	if (!rx->sta || data_len < 0)
 		return RX_DROP_UNUSABLE;
@@ -749,6 +752,9 @@ ieee80211_crypto_gcmp_decrypt(struct iee
 			return RX_DROP_UNUSABLE;
 	}
 
+	/* reload hdr - skb might have been reallocated */
+	hdr = (void *)rx->skb->data;
+
 	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 	if (!rx->sta || data_len < 0)
 		return RX_DROP_UNUSABLE;


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ