4.14-stable patches

added patches:
	mac80211-fix-potential-double-free-on-mesh-join.patch

diff --git a/queue-4.14/mac80211-fix-potential-double-free-on-mesh-join.patch b/queue-4.14/mac80211-fix-potential-double-free-on-mesh-join.patch
new file mode 100644 (file)
index 0000000..79da12d
--- /dev/null
+++ b/queue-4.14/mac80211-fix-potential-double-free-on-mesh-join.patch
@@ -0,0 +1,83 @@
+From 4a2d4496e15ea5bb5c8e83b94ca8ca7fb045e7d3 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Linus=20L=C3=BCssing?= <ll@simonwunderlich.de>
+Date: Thu, 10 Mar 2022 19:35:13 +0100
+Subject: mac80211: fix potential double free on mesh join
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+From: Linus Lüssing <ll@simonwunderlich.de>
+
+commit 4a2d4496e15ea5bb5c8e83b94ca8ca7fb045e7d3 upstream.
+
+While commit 6a01afcf8468 ("mac80211: mesh: Free ie data when leaving
+mesh") fixed a memory leak on mesh leave / teardown it introduced a
+potential memory corruption caused by a double free when rejoining the
+mesh:
+
+  ieee80211_leave_mesh()
+  -> kfree(sdata->u.mesh.ie);
+  ...
+  ieee80211_join_mesh()
+  -> copy_mesh_setup()
+     -> old_ie = ifmsh->ie;
+     -> kfree(old_ie);
+
+This double free / kernel panics can be reproduced by using wpa_supplicant
+with an encrypted mesh (if set up without encryption via "iw" then
+ifmsh->ie is always NULL, which avoids this issue). And then calling:
+
+  $ iw dev mesh0 mesh leave
+  $ iw dev mesh0 mesh join my-mesh
+
+Note that typically these commands are not used / working when using
+wpa_supplicant. And it seems that wpa_supplicant or wpa_cli are going
+through a NETDEV_DOWN/NETDEV_UP cycle between a mesh leave and mesh join
+where the NETDEV_UP resets the mesh.ie to NULL via a memcpy of
+default_mesh_setup in cfg80211_netdev_notifier_call, which then avoids
+the memory corruption, too.
+
+The issue was first observed in an application which was not using
+wpa_supplicant but "Senf" instead, which implements its own calls to
+nl80211.
+
+Fixing the issue by removing the kfree()'ing of the mesh IE in the mesh
+join function and leaving it solely up to the mesh leave to free the
+mesh IE.
+
+Cc: stable@vger.kernel.org
+Fixes: 6a01afcf8468 ("mac80211: mesh: Free ie data when leaving mesh")
+Reported-by: Matthias Kretschmer <mathias.kretschmer@fit.fraunhofer.de>
+Signed-off-by: Linus Lüssing <ll@simonwunderlich.de>
+Tested-by: Mathias Kretschmer <mathias.kretschmer@fit.fraunhofer.de>
+Link: https://lore.kernel.org/r/20220310183513.28589-1-linus.luessing@c0d3.blue
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/mac80211/cfg.c |    3 ---
+ 1 file changed, 3 deletions(-)
+
+--- a/net/mac80211/cfg.c
++++ b/net/mac80211/cfg.c
+@@ -1811,13 +1811,11 @@ static int copy_mesh_setup(struct ieee80
+               const struct mesh_setup *setup)
+ {
+       u8 *new_ie;
+-      const u8 *old_ie;
+       struct ieee80211_sub_if_data *sdata = container_of(ifmsh,
+                                       struct ieee80211_sub_if_data, u.mesh);
+ 
+       /* allocate information elements */
+       new_ie = NULL;
+-      old_ie = ifmsh->ie;
+ 
+       if (setup->ie_len) {
+               new_ie = kmemdup(setup->ie, setup->ie_len,
+@@ -1827,7 +1825,6 @@ static int copy_mesh_setup(struct ieee80
+       }
+       ifmsh->ie_len = setup->ie_len;
+       ifmsh->ie = new_ie;
+-      kfree(old_ie);
+ 
+       /* now copy the rest of the setup parameters */
+       ifmsh->mesh_id_len = setup->mesh_id_len;

diff --git a/queue-4.14/series b/queue-4.14/series
index 88d569d44b40138cf248add7734ee28af827e718..ee85135c44bfe768ad230cb73b9d9c0a017f965a 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -14,3 +14,4 @@ acpi-x86-work-around-broken-xsdt-on-advantech-dac-bj01-board.patch
 acpi-battery-add-device-hid-and-quirk-for-microsoft-surface-go-3.patch
 acpi-video-force-backlight-native-for-clevo-nl5xru-and-nl5xnu.patch
 crypto-qat-disable-registration-of-algorithms.patch
+mac80211-fix-potential-double-free-on-mesh-join.patch