All of lore.kernel.org
 help / color / mirror / Atom feed
From: <gregkh@linuxfoundation.org>
To: nbd@nbd.name, sean.wang@mediatek.com
Cc: <stable@vger.kernel.org>
Subject: FAILED: patch "[PATCH] mt76: fix use-after-free by removing a non-RCU wcid pointer" failed to apply to 5.10-stable tree
Date: Mon, 06 Jun 2022 16:53:32 +0200	[thread overview]
Message-ID: <16545272122075@kroah.com> (raw)


The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 51fb1278aa57ae0fc54adaa786e1965362bed4fb Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Fri, 25 Mar 2022 22:01:43 +0100
Subject: [PATCH] mt76: fix use-after-free by removing a non-RCU wcid pointer

Fixes an issue caught by KASAN about use-after-free in mt76_txq_schedule
by protecting mtxq->wcid with rcu_lock between mt76_txq_schedule and
sta_info_[alloc, free].

[18853.876689] ==================================================================
[18853.876751] BUG: KASAN: use-after-free in mt76_txq_schedule+0x204/0xaf8 [mt76]
[18853.876773] Read of size 8 at addr ffffffaf989a2138 by task mt76-tx phy0/883
[18853.876786]
[18853.876810] CPU: 5 PID: 883 Comm: mt76-tx phy0 Not tainted 5.10.100-fix-510-56778d365941-kasan #5 0b01fbbcf41a530f52043508fec2e31a4215

[18853.876840] Call trace:
[18853.876861]  dump_backtrace+0x0/0x3ec
[18853.876878]  show_stack+0x20/0x2c
[18853.876899]  dump_stack+0x11c/0x1ac
[18853.876918]  print_address_description+0x74/0x514
[18853.876934]  kasan_report+0x134/0x174
[18853.876948]  __asan_report_load8_noabort+0x44/0x50
[18853.876976]  mt76_txq_schedule+0x204/0xaf8 [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2]
[18853.877002]  mt76_txq_schedule_all+0x2c/0x48 [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2]
[18853.877030]  mt7921_tx_worker+0xa0/0x1cc [mt7921_common f0875ebac9d7b4754e1010549e7db50fbd90a047]
[18853.877054]  __mt76_worker_fn+0x190/0x22c [mt76 074e03e4640e97fe7405ee1fab547b81c4fa45d2]
[18853.877071]  kthread+0x2f8/0x3b8
[18853.877087]  ret_from_fork+0x10/0x30
[18853.877098]
[18853.877112] Allocated by task 941:
[18853.877131]  kasan_save_stack+0x38/0x68
[18853.877147]  __kasan_kmalloc+0xd4/0xfc
[18853.877163]  kasan_kmalloc+0x10/0x1c
[18853.877177]  __kmalloc+0x264/0x3c4
[18853.877294]  sta_info_alloc+0x460/0xf88 [mac80211]
[18853.877410]  ieee80211_prep_connection+0x204/0x1ee0 [mac80211]
[18853.877523]  ieee80211_mgd_auth+0x6c4/0xa4c [mac80211]
[18853.877635]  ieee80211_auth+0x20/0x2c [mac80211]
[18853.877733]  rdev_auth+0x7c/0x438 [cfg80211]
[18853.877826]  cfg80211_mlme_auth+0x26c/0x390 [cfg80211]
[18853.877919]  nl80211_authenticate+0x6d4/0x904 [cfg80211]
[18853.877938]  genl_rcv_msg+0x748/0x93c
[18853.877954]  netlink_rcv_skb+0x160/0x2a8
[18853.877969]  genl_rcv+0x3c/0x54
[18853.877985]  netlink_unicast_kernel+0x104/0x1ec
[18853.877999]  netlink_unicast+0x178/0x268
[18853.878015]  netlink_sendmsg+0x3cc/0x5f0
[18853.878030]  sock_sendmsg+0xb4/0xd8
[18853.878043]  ____sys_sendmsg+0x2f8/0x53c
[18853.878058]  ___sys_sendmsg+0xe8/0x150
[18853.878071]  __sys_sendmsg+0xc4/0x1f4
[18853.878087]  __arm64_compat_sys_sendmsg+0x88/0x9c
[18853.878101]  el0_svc_common+0x1b4/0x390
[18853.878115]  do_el0_svc_compat+0x8c/0xdc
[18853.878131]  el0_svc_compat+0x10/0x1c
[18853.878146]  el0_sync_compat_handler+0xa8/0xcc
[18853.878161]  el0_sync_compat+0x188/0x1c0
[18853.878171]
[18853.878183] Freed by task 10927:
[18853.878200]  kasan_save_stack+0x38/0x68
[18853.878215]  kasan_set_track+0x28/0x3c
[18853.878228]  kasan_set_free_info+0x24/0x48
[18853.878244]  __kasan_slab_free+0x11c/0x154
[18853.878259]  kasan_slab_free+0x14/0x24
[18853.878273]  slab_free_freelist_hook+0xac/0x1b0
[18853.878287]  kfree+0x104/0x390
[18853.878402]  sta_info_free+0x198/0x210 [mac80211]
[18853.878515]  __sta_info_destroy_part2+0x230/0x2d4 [mac80211]
[18853.878628]  __sta_info_flush+0x300/0x37c [mac80211]
[18853.878740]  ieee80211_set_disassoc+0x2cc/0xa7c [mac80211]
[18853.878851]  ieee80211_mgd_deauth+0x4a4/0x10a0 [mac80211]
[18853.878962]  ieee80211_deauth+0x20/0x2c [mac80211]
[18853.879057]  rdev_deauth+0x7c/0x438 [cfg80211]
[18853.879150]  cfg80211_mlme_deauth+0x274/0x414 [cfg80211]
[18853.879243]  cfg80211_mlme_down+0xe4/0x118 [cfg80211]
[18853.879335]  cfg80211_disconnect+0x218/0x2d8 [cfg80211]
[18853.879427]  __cfg80211_leave+0x17c/0x240 [cfg80211]
[18853.879519]  cfg80211_leave+0x3c/0x58 [cfg80211]
[18853.879611]  wiphy_suspend+0xdc/0x200 [cfg80211]
[18853.879628]  dpm_run_callback+0x58/0x408
[18853.879642]  __device_suspend+0x4cc/0x864
[18853.879658]  async_suspend+0x34/0xf4
[18853.879673]  async_run_entry_fn+0xe0/0x37c
[18853.879689]  process_one_work+0x508/0xb98
[18853.879702]  worker_thread+0x7f4/0xcd4
[18853.879717]  kthread+0x2f8/0x3b8
[18853.879731]  ret_from_fork+0x10/0x30
[18853.879741]
[18853.879757] The buggy address belongs to the object at ffffffaf989a2000
[18853.879757]  which belongs to the cache kmalloc-8k of size 8192
[18853.879774] The buggy address is located 312 bytes inside of
[18853.879774]  8192-byte region [ffffffaf989a2000, ffffffaf989a4000)
[18853.879787] The buggy address belongs to the page:
[18853.879807] page:000000004bda2a59 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d89a0
[18853.879823] head:000000004bda2a59 order:3 compound_mapcount:0 compound_pincount:0
[18853.879839] flags: 0x8000000000010200(slab|head)
[18853.879857] raw: 8000000000010200 ffffffffbc89e208 ffffffffb7fb5208 ffffffaec000cc80
[18853.879873] raw: 0000000000000000 0000000000010001 00000001ffffffff 0000000000000000
[18853.879885] page dumped because: kasan: bad access detected
[18853.879896]
[18853.879907] Memory state around the buggy address:
[18853.879922]  ffffffaf989a2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18853.879935]  ffffffaf989a2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18853.879948] >ffffffaf989a2100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18853.879961]                                         ^
[18853.879973]  ffffffaf989a2180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18853.879986]  ffffffaf989a2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18853.879998] ==================================================================

Cc: stable@vger.kernel.org
Reported-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c
index 5b53d008eb66..026ab1e16d45 100644
--- a/drivers/net/wireless/mediatek/mt76/mac80211.c
+++ b/drivers/net/wireless/mediatek/mt76/mac80211.c
@@ -1303,7 +1303,7 @@ mt76_sta_add(struct mt76_dev *dev, struct ieee80211_vif *vif,
 			continue;
 
 		mtxq = (struct mt76_txq *)sta->txq[i]->drv_priv;
-		mtxq->wcid = wcid;
+		mtxq->wcid = wcid->idx;
 	}
 
 	ewma_signal_init(&wcid->rssi);
diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index 882fb5d2517f..522c523d5c41 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -275,7 +275,7 @@ struct mt76_wcid {
 };
 
 struct mt76_txq {
-	struct mt76_wcid *wcid;
+	u16 wcid;
 
 	u16 agg_ssn;
 	bool send_bar;
diff --git a/drivers/net/wireless/mediatek/mt76/mt7603/main.c b/drivers/net/wireless/mediatek/mt76/mt7603/main.c
index 83c5eec5b163..1d098e9799dd 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7603/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7603/main.c
@@ -75,7 +75,7 @@ mt7603_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 	mt7603_wtbl_init(dev, idx, mvif->idx, bc_addr);
 
 	mtxq = (struct mt76_txq *)vif->txq->drv_priv;
-	mtxq->wcid = &mvif->sta.wcid;
+	mtxq->wcid = idx;
 	rcu_assign_pointer(dev->mt76.wcid[idx], &mvif->sta.wcid);
 
 out:
diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/main.c b/drivers/net/wireless/mediatek/mt76/mt7615/main.c
index d79cbdbd5a05..6b8e3e7ae4a2 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7615/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/main.c
@@ -234,7 +234,7 @@ static int mt7615_add_interface(struct ieee80211_hw *hw,
 	rcu_assign_pointer(dev->mt76.wcid[idx], &mvif->sta.wcid);
 	if (vif->txq) {
 		mtxq = (struct mt76_txq *)vif->txq->drv_priv;
-		mtxq->wcid = &mvif->sta.wcid;
+		mtxq->wcid = idx;
 	}
 
 	ret = mt7615_mcu_add_dev_info(phy, vif, true);
diff --git a/drivers/net/wireless/mediatek/mt76/mt76x02_util.c b/drivers/net/wireless/mediatek/mt76/mt76x02_util.c
index dd30f537676d..be1d27de993a 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76x02_util.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76x02_util.c
@@ -292,7 +292,8 @@ mt76x02_vif_init(struct mt76x02_dev *dev, struct ieee80211_vif *vif,
 	mt76_packet_id_init(&mvif->group_wcid);
 
 	mtxq = (struct mt76_txq *)vif->txq->drv_priv;
-	mtxq->wcid = &mvif->group_wcid;
+	rcu_assign_pointer(dev->mt76.wcid[MT_VIF_WCID(idx)], &mvif->group_wcid);
+	mtxq->wcid = MT_VIF_WCID(idx);
 }
 
 int
@@ -345,6 +346,7 @@ void mt76x02_remove_interface(struct ieee80211_hw *hw,
 	struct mt76x02_vif *mvif = (struct mt76x02_vif *)vif->drv_priv;
 
 	dev->mt76.vif_mask &= ~BIT(mvif->idx);
+	rcu_assign_pointer(dev->mt76.wcid[mvif->group_wcid.idx], NULL);
 	mt76_packet_id_flush(&dev->mt76, &mvif->group_wcid);
 }
 EXPORT_SYMBOL_GPL(mt76x02_remove_interface);
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/main.c b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
index c3f44d801e7f..187cf4ccd36e 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
@@ -246,7 +246,7 @@ static int mt7915_add_interface(struct ieee80211_hw *hw,
 	rcu_assign_pointer(dev->mt76.wcid[idx], &mvif->sta.wcid);
 	if (vif->txq) {
 		mtxq = (struct mt76_txq *)vif->txq->drv_priv;
-		mtxq->wcid = &mvif->sta.wcid;
+		mtxq->wcid = idx;
 	}
 
 	if (vif->type != NL80211_IFTYPE_AP &&
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
index fdaf2451bc1d..2173c3e9723f 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
@@ -330,7 +330,7 @@ static int mt7921_add_interface(struct ieee80211_hw *hw,
 	rcu_assign_pointer(dev->mt76.wcid[idx], &mvif->sta.wcid);
 	if (vif->txq) {
 		mtxq = (struct mt76_txq *)vif->txq->drv_priv;
-		mtxq->wcid = &mvif->sta.wcid;
+		mtxq->wcid = idx;
 	}
 
 out:
diff --git a/drivers/net/wireless/mediatek/mt76/tx.c b/drivers/net/wireless/mediatek/mt76/tx.c
index 830963a65b34..c3be62f58b62 100644
--- a/drivers/net/wireless/mediatek/mt76/tx.c
+++ b/drivers/net/wireless/mediatek/mt76/tx.c
@@ -436,12 +436,11 @@ mt76_txq_stopped(struct mt76_queue *q)
 
 static int
 mt76_txq_send_burst(struct mt76_phy *phy, struct mt76_queue *q,
-		    struct mt76_txq *mtxq)
+		    struct mt76_txq *mtxq, struct mt76_wcid *wcid)
 {
 	struct mt76_dev *dev = phy->dev;
 	struct ieee80211_txq *txq = mtxq_to_txq(mtxq);
 	enum mt76_txq_id qid = mt76_txq_get_qid(txq);
-	struct mt76_wcid *wcid = mtxq->wcid;
 	struct ieee80211_tx_info *info;
 	struct sk_buff *skb;
 	int n_frames = 1;
@@ -527,8 +526,8 @@ mt76_txq_schedule_list(struct mt76_phy *phy, enum mt76_txq_id qid)
 			break;
 
 		mtxq = (struct mt76_txq *)txq->drv_priv;
-		wcid = mtxq->wcid;
-		if (wcid && test_bit(MT_WCID_FLAG_PS, &wcid->flags))
+		wcid = rcu_dereference(dev->wcid[mtxq->wcid]);
+		if (!wcid || test_bit(MT_WCID_FLAG_PS, &wcid->flags))
 			continue;
 
 		if (mtxq->send_bar && mtxq->aggr) {
@@ -543,7 +542,7 @@ mt76_txq_schedule_list(struct mt76_phy *phy, enum mt76_txq_id qid)
 		}
 
 		if (!mt76_txq_stopped(q))
-			n_frames = mt76_txq_send_burst(phy, q, mtxq);
+			n_frames = mt76_txq_send_burst(phy, q, mtxq, wcid);
 
 		ieee80211_return_txq(phy->hw, txq, false);
 


                 reply	other threads:[~2022-06-06 14:53 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=16545272122075@kroah.com \
    --to=gregkh@linuxfoundation.org \
    --cc=nbd@nbd.name \
    --cc=sean.wang@mediatek.com \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.