[PATCH AUTOSEL 4.9 08/13] nl80211: fix null pointer dereference

[PATCH AUTOSEL 4.9 08/13] nl80211: fix null pointer dereference

[Sasha Levin]

From: Miaoqing Pan <miaoqing@codeaurora.org>

[ Upstream commit b501426cf86e70649c983c52f4c823b3c40d72a3 ]

If the interface is not in MESH mode, the command 'iw wlanx mpath del'
will cause kernel panic.

The root cause is null pointer access in mpp_flush_by_proxy(), as the
pointer 'sdata->u.mesh.mpp_paths' is NULL for non MESH interface.

Unable to handle kernel NULL pointer dereference at virtual address 00000068
[...]
PC is at _raw_spin_lock_bh+0x20/0x5c
LR is at mesh_path_del+0x1c/0x17c [mac80211]
[...]
Process iw (pid: 4537, stack limit = 0xd83e0238)
[...]
[<c021211c>] (_raw_spin_lock_bh) from [<bf8c7648>] (mesh_path_del+0x1c/0x17c [mac80211])
[<bf8c7648>] (mesh_path_del [mac80211]) from [<bf6cdb7c>] (extack_doit+0x20/0x68 [compat])
[<bf6cdb7c>] (extack_doit [compat]) from [<c05c309c>] (genl_rcv_msg+0x274/0x30c)
[<c05c309c>] (genl_rcv_msg) from [<c05c25d8>] (netlink_rcv_skb+0x58/0xac)
[<c05c25d8>] (netlink_rcv_skb) from [<c05c2e14>] (genl_rcv+0x20/0x34)
[<c05c2e14>] (genl_rcv) from [<c05c1f90>] (netlink_unicast+0x11c/0x204)
[<c05c1f90>] (netlink_unicast) from [<c05c2420>] (netlink_sendmsg+0x30c/0x370)
[<c05c2420>] (netlink_sendmsg) from [<c05886d0>] (sock_sendmsg+0x70/0x84)
[<c05886d0>] (sock_sendmsg) from [<c0589f4c>] (___sys_sendmsg.part.3+0x188/0x228)
[<c0589f4c>] (___sys_sendmsg.part.3) from [<c058add4>] (__sys_sendmsg+0x4c/0x70)
[<c058add4>] (__sys_sendmsg) from [<c0208c80>] (ret_fast_syscall+0x0/0x44)
Code: e2822c02 e2822001 e5832004 f590f000 (e1902f9f)
---[ end trace bbd717600f8f884d ]---

Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Link: https://lore.kernel.org/r/1569485810-761-1-git-send-email-miaoqing@codeaurora.org
[trim useless data from commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/wireless/nl80211.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d6e6293157717..3d49488c3013a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5321,6 +5321,9 @@ static int nl80211_del_mpath(struct sk_buff *skb, struct genl_info *info)
 	if (!rdev->ops->del_mpath)
 		return -EOPNOTSUPP;
 
+	if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
+		return -EOPNOTSUPP;
+
 	return rdev_del_mpath(rdev, dev, dst);
 }
 
-- 
2.20.1

[PATCH AUTOSEL 4.9 09/13] mac80211: fix txq null pointer dereference

[Sasha Levin]

From: Miaoqing Pan <miaoqing@codeaurora.org>

[ Upstream commit 8ed31a264065ae92058ce54aa3cc8da8d81dc6d7 ]

If the interface type is P2P_DEVICE or NAN, read the file of
'/sys/kernel/debug/ieee80211/phyx/netdev:wlanx/aqm' will get a
NULL pointer dereference. As for those interface type, the
pointer sdata->vif.txq is NULL.

Unable to handle kernel NULL pointer dereference at virtual address 00000011
CPU: 1 PID: 30936 Comm: cat Not tainted 4.14.104 #1
task: ffffffc0337e4880 task.stack: ffffff800cd20000
PC is at ieee80211_if_fmt_aqm+0x34/0xa0 [mac80211]
LR is at ieee80211_if_fmt_aqm+0x34/0xa0 [mac80211]
[...]
Process cat (pid: 30936, stack limit = 0xffffff800cd20000)
[...]
[<ffffff8000b7cd00>] ieee80211_if_fmt_aqm+0x34/0xa0 [mac80211]
[<ffffff8000b7c414>] ieee80211_if_read+0x60/0xbc [mac80211]
[<ffffff8000b7ccc4>] ieee80211_if_read_aqm+0x28/0x30 [mac80211]
[<ffffff80082eff94>] full_proxy_read+0x2c/0x48
[<ffffff80081eef00>] __vfs_read+0x2c/0xd4
[<ffffff80081ef084>] vfs_read+0x8c/0x108
[<ffffff80081ef494>] SyS_read+0x40/0x7c

Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/1569549796-8223-1-git-send-email-miaoqing@codeaurora.org
[trim useless data from commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/mac80211/debugfs_netdev.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c
index bcec1240f41d9..9769db9818d2f 100644
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -490,9 +490,14 @@ static ssize_t ieee80211_if_fmt_aqm(
 	const struct ieee80211_sub_if_data *sdata, char *buf, int buflen)
 {
 	struct ieee80211_local *local = sdata->local;
-	struct txq_info *txqi = to_txq_info(sdata->vif.txq);
+	struct txq_info *txqi;
 	int len;
 
+	if (!sdata->vif.txq)
+		return 0;
+
+	txqi = to_txq_info(sdata->vif.txq);
+
 	spin_lock_bh(&local->fq.lock);
 	rcu_read_lock();
 
@@ -657,7 +662,9 @@ static void add_common_files(struct ieee80211_sub_if_data *sdata)
 	DEBUGFS_ADD(rc_rateidx_vht_mcs_mask_5ghz);
 	DEBUGFS_ADD(hw_queues);
 
-	if (sdata->local->ops->wake_tx_queue)
+	if (sdata->local->ops->wake_tx_queue &&
+	    sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
+	    sdata->vif.type != NL80211_IFTYPE_NAN)
 		DEBUGFS_ADD(aqm);
 }
 
-- 
2.20.1