From 8a9f82ff15da03a6804cdd6557fb36ff71c0924f Mon Sep 17 00:00:00 2001
From: Roger Quadros <rogerq@kernel.org>
Date: Mon, 10 Feb 2025 16:52:16 +0200
Subject: [PATCH 01/16] net: ethernet: ti: am65-cpsw: fix RX & TX statistics
 for XDP_TX case

For successful XDP_TX and XDP_REDIRECT cases, the packet was received
successfully so update RX statistics. Use original received
packet length for that.

TX packets statistics are incremented on TX completion so don't
update it while TX queueing.

If xdp_convert_buff_to_frame() fails, increment tx_dropped.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
Fixes: 8acacc40f733 ("net: ethernet: ti: am65-cpsw: Add minimal XDP support")
Link: https://patch.msgid.link/20250210-am65-cpsw-xdp-fixes-v1-2-ec6b1f7f1aca@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 021c5a4df8fd..38f3be310928 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -1170,9 +1170,11 @@ static int am65_cpsw_run_xdp(struct am65_cpsw_rx_flow *flow,
 	struct xdp_frame *xdpf;
 	struct bpf_prog *prog;
 	struct page *page;
+	int pkt_len;
 	u32 act;
 	int err;
 
+	pkt_len = *len;
 	prog = READ_ONCE(port->xdp_prog);
 	if (!prog)
 		return AM65_CPSW_XDP_PASS;
@@ -1190,8 +1192,10 @@ static int am65_cpsw_run_xdp(struct am65_cpsw_rx_flow *flow,
 		netif_txq = netdev_get_tx_queue(ndev, tx_chn->id);
 
 		xdpf = xdp_convert_buff_to_frame(xdp);
-		if (unlikely(!xdpf))
+		if (unlikely(!xdpf)) {
+			ndev->stats.tx_dropped++;
 			goto drop;
+		}
 
 		__netif_tx_lock(netif_txq, cpu);
 		err = am65_cpsw_xdp_tx_frame(ndev, tx_chn, xdpf,
@@ -1200,14 +1204,14 @@ static int am65_cpsw_run_xdp(struct am65_cpsw_rx_flow *flow,
 		if (err)
 			goto drop;
 
-		dev_sw_netstats_tx_add(ndev, 1, *len);
+		dev_sw_netstats_rx_add(ndev, pkt_len);
 		ret = AM65_CPSW_XDP_CONSUMED;
 		goto out;
 	case XDP_REDIRECT:
 		if (unlikely(xdp_do_redirect(ndev, xdp, prog)))
 			goto drop;
 
-		dev_sw_netstats_rx_add(ndev, *len);
+		dev_sw_netstats_rx_add(ndev, pkt_len);
 		ret = AM65_CPSW_XDP_REDIRECT;
 		goto out;
 	default:
-- 
2.51.0


From 4542536f664f752db5feba2c5998b165933c34f2 Mon Sep 17 00:00:00 2001
From: Roger Quadros <rogerq@kernel.org>
Date: Mon, 10 Feb 2025 16:52:17 +0200
Subject: [PATCH 02/16] net: ethernet: ti: am65_cpsw: fix tx_cleanup for XDP
 case

For XDP transmit case, swdata doesn't contain SKB but the
XDP Frame. Infer the correct swdata based on buffer type
and return the XDP Frame for XDP transmit case.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
Fixes: 8acacc40f733 ("net: ethernet: ti: am65-cpsw: Add minimal XDP support")
Link: https://patch.msgid.link/20250210-am65-cpsw-xdp-fixes-v1-3-ec6b1f7f1aca@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 38f3be310928..2806238629f8 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -828,16 +828,24 @@ static void am65_cpsw_nuss_xmit_free(struct am65_cpsw_tx_chn *tx_chn,
 static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma)
 {
 	struct am65_cpsw_tx_chn *tx_chn = data;
+	enum am65_cpsw_tx_buf_type buf_type;
 	struct cppi5_host_desc_t *desc_tx;
+	struct xdp_frame *xdpf;
 	struct sk_buff *skb;
 	void **swdata;
 
 	desc_tx = k3_cppi_desc_pool_dma2virt(tx_chn->desc_pool, desc_dma);
 	swdata = cppi5_hdesc_get_swdata(desc_tx);
-	skb = *(swdata);
-	am65_cpsw_nuss_xmit_free(tx_chn, desc_tx);
+	buf_type = am65_cpsw_nuss_buf_type(tx_chn, desc_dma);
+	if (buf_type == AM65_CPSW_TX_BUF_TYPE_SKB) {
+		skb = *(swdata);
+		dev_kfree_skb_any(skb);
+	} else {
+		xdpf = *(swdata);
+		xdp_return_frame(xdpf);
+	}
 
-	dev_kfree_skb_any(skb);
+	am65_cpsw_nuss_xmit_free(tx_chn, desc_tx);
 }
 
 static struct sk_buff *am65_cpsw_build_skb(void *page_addr,
-- 
2.51.0


From e00a2e5d485faf53c7a24b9d1b575a642227947f Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@intel.com>
Date: Wed, 12 Feb 2025 18:18:51 +0200
Subject: [PATCH 03/16] drm: Fix DSC BPP increment decoding

Starting with DPCD version 2.0 bits 6:3 of the DP_DSC_BITS_PER_PIXEL_INC
DPCD register contains the NativeYCbCr422_MAX_bpp_DELTA field, which can
be non-zero as opposed to earlier DPCD versions, hence decoding the
bit_per_pixel increment value at bits 2:0 in the same register requires
applying a mask, do so.

Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Fixes: 0c2287c96521 ("drm/display/dp: Add helper function to get DSC bpp precision")
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250212161851.4007005-1-imre.deak@intel.com
---
 drivers/gpu/drm/display/drm_dp_helper.c | 2 +-
 include/drm/display/drm_dp.h            | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c
index da3c8521a7fa..61c7c2c588c6 100644
--- a/drivers/gpu/drm/display/drm_dp_helper.c
+++ b/drivers/gpu/drm/display/drm_dp_helper.c
@@ -2544,7 +2544,7 @@ u8 drm_dp_dsc_sink_bpp_incr(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE])
 {
 	u8 bpp_increment_dpcd = dsc_dpcd[DP_DSC_BITS_PER_PIXEL_INC - DP_DSC_SUPPORT];
 
-	switch (bpp_increment_dpcd) {
+	switch (bpp_increment_dpcd & DP_DSC_BITS_PER_PIXEL_MASK) {
 	case DP_DSC_BITS_PER_PIXEL_1_16:
 		return 16;
 	case DP_DSC_BITS_PER_PIXEL_1_8:
diff --git a/include/drm/display/drm_dp.h b/include/drm/display/drm_dp.h
index a6f8b098c56f..3bd9f482f0c3 100644
--- a/include/drm/display/drm_dp.h
+++ b/include/drm/display/drm_dp.h
@@ -359,6 +359,7 @@
 # define DP_DSC_BITS_PER_PIXEL_1_4          0x2
 # define DP_DSC_BITS_PER_PIXEL_1_2          0x3
 # define DP_DSC_BITS_PER_PIXEL_1_1          0x4
+# define DP_DSC_BITS_PER_PIXEL_MASK         0x7
 
 #define DP_PSR_SUPPORT                      0x070   /* XXX 1.2? */
 # define DP_PSR_IS_SUPPORTED                1
-- 
2.51.0


From b4f82f9ed43aefa79bec2504ae8c29be0c0f5d1d Mon Sep 17 00:00:00 2001
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Thu, 16 Jan 2025 10:35:03 -0500
Subject: [PATCH 04/16] Bluetooth: L2CAP: Fix slab-use-after-free Read in
 l2cap_send_cmd

After the hci sync command releases l2cap_conn, the hci receive data work
queue references the released l2cap_conn when sending to the upper layer.
Add hci dev lock to the hci receive data work queue to synchronize the two.

[1]
BUG: KASAN: slab-use-after-free in l2cap_send_cmd+0x187/0x8d0 net/bluetooth/l2cap_core.c:954
Read of size 8 at addr ffff8880271a4000 by task kworker/u9:2/5837

CPU: 0 UID: 0 PID: 5837 Comm: kworker/u9:2 Not tainted 6.13.0-rc5-syzkaller-00163-gab75170520d4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: hci1 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 l2cap_build_cmd net/bluetooth/l2cap_core.c:2964 [inline]
 l2cap_send_cmd+0x187/0x8d0 net/bluetooth/l2cap_core.c:954
 l2cap_sig_send_rej net/bluetooth/l2cap_core.c:5502 [inline]
 l2cap_sig_channel net/bluetooth/l2cap_core.c:5538 [inline]
 l2cap_recv_frame+0x221f/0x10db0 net/bluetooth/l2cap_core.c:6817
 hci_acldata_packet net/bluetooth/hci_core.c:3797 [inline]
 hci_rx_work+0x508/0xdb0 net/bluetooth/hci_core.c:4040
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 5837:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6860
 l2cap_connect_cfm+0x115/0x1090 net/bluetooth/l2cap_core.c:7239
 hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]
 hci_remote_features_evt+0x68e/0xac0 net/bluetooth/hci_event.c:3726
 hci_event_func net/bluetooth/hci_event.c:7473 [inline]
 hci_event_packet+0xac2/0x1540 net/bluetooth/hci_event.c:7525
 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4035
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 54:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4613 [inline]
 kfree+0x196/0x430 mm/slub.c:4761
 l2cap_connect_cfm+0xcc/0x1090 net/bluetooth/l2cap_core.c:7235
 hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]
 hci_conn_failed+0x287/0x400 net/bluetooth/hci_conn.c:1266
 hci_abort_conn_sync+0x56c/0x11f0 net/bluetooth/hci_sync.c:5603
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Reported-by: syzbot+31c2f641b850a348a734@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=31c2f641b850a348a734
Tested-by: syzbot+31c2f641b850a348a734@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 net/bluetooth/l2cap_core.c | 39 +++++++++++++++++++++++++++++++++-----
 1 file changed, 34 insertions(+), 5 deletions(-)

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 27b4c4a2ba1f..adb8c33ac595 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -948,6 +948,16 @@ static u8 l2cap_get_ident(struct l2cap_conn *conn)
 	return id;
 }
 
+static void l2cap_send_acl(struct l2cap_conn *conn, struct sk_buff *skb,
+			   u8 flags)
+{
+	/* Check if the hcon still valid before attempting to send */
+	if (hci_conn_valid(conn->hcon->hdev, conn->hcon))
+		hci_send_acl(conn->hchan, skb, flags);
+	else
+		kfree_skb(skb);
+}
+
 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
 			   void *data)
 {
@@ -970,7 +980,7 @@ static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
 	bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
 	skb->priority = HCI_PRIO_MAX;
 
-	hci_send_acl(conn->hchan, skb, flags);
+	l2cap_send_acl(conn, skb, flags);
 }
 
 static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
@@ -1792,13 +1802,10 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 
 	mutex_unlock(&conn->chan_lock);
 
-	hci_chan_del(conn->hchan);
-
 	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
 		cancel_delayed_work_sync(&conn->info_timer);
 
 	hcon->l2cap_data = NULL;
-	conn->hchan = NULL;
 	l2cap_conn_put(conn);
 }
 
@@ -1806,6 +1813,7 @@ static void l2cap_conn_free(struct kref *ref)
 {
 	struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
 
+	hci_chan_del(conn->hchan);
 	hci_conn_put(conn->hcon);
 	kfree(conn);
 }
@@ -7466,14 +7474,33 @@ static void l2cap_recv_reset(struct l2cap_conn *conn)
 	conn->rx_len = 0;
 }
 
+static struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c)
+{
+	BT_DBG("conn %p orig refcnt %u", c, kref_read(&c->ref));
+
+	if (!kref_get_unless_zero(&c->ref))
+		return NULL;
+
+	return c;
+}
+
 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 {
-	struct l2cap_conn *conn = hcon->l2cap_data;
+	struct l2cap_conn *conn;
 	int len;
 
+	/* Lock hdev to access l2cap_data to avoid race with l2cap_conn_del */
+	hci_dev_lock(hcon->hdev);
+
+	conn = hcon->l2cap_data;
+
 	if (!conn)
 		conn = l2cap_conn_add(hcon);
 
+	conn = l2cap_conn_hold_unless_zero(conn);
+
+	hci_dev_unlock(hcon->hdev);
+
 	if (!conn)
 		goto drop;
 
@@ -7565,6 +7592,8 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 		break;
 	}
 
+	l2cap_conn_put(conn);
+
 drop:
 	kfree_skb(skb);
 }
-- 
2.51.0


From 872274b992839ff64fe560767fe7ee5f942ccdb1 Mon Sep 17 00:00:00 2001
From: Kiran K <kiran.k@intel.com>
Date: Fri, 31 Jan 2025 18:30:19 +0530
Subject: [PATCH 05/16] Bluetooth: btintel_pcie: Fix a potential race condition

On HCI_OP_RESET command, firmware raises alive interrupt. Driver needs
to wait for this before sending other command. This patch fixes the potential
miss of alive interrupt due to which HCI_OP_RESET can timeout.

Expected flow:
If tx command is HCI_OP_RESET,
  1. set data->gp0_received = false
  2. send HCI_OP_RESET
  3. wait for alive interrupt

Actual flow having potential race:
If tx command is HCI_OP_RESET,
 1. send HCI_OP_RESET
   1a. Firmware raises alive interrupt here and in ISR
       data->gp0_received  is set to true
 2. set data->gp0_received = false
 3. wait for alive interrupt

Signed-off-by: Kiran K <kiran.k@intel.com>
Fixes: 05c200c8f029 ("Bluetooth: btintel_pcie: Add handshake between driver and firmware")
Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Closes: https://patchwork.kernel.org/project/bluetooth/patch/20241001104451.626964-1-kiran.k@intel.com/
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 drivers/bluetooth/btintel_pcie.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btintel_pcie.c b/drivers/bluetooth/btintel_pcie.c
index 2b79952f3628..091ffe3e1495 100644
--- a/drivers/bluetooth/btintel_pcie.c
+++ b/drivers/bluetooth/btintel_pcie.c
@@ -1320,6 +1320,10 @@ static int btintel_pcie_send_frame(struct hci_dev *hdev,
 			if (opcode == 0xfc01)
 				btintel_pcie_inject_cmd_complete(hdev, opcode);
 		}
+		/* Firmware raises alive interrupt on HCI_OP_RESET */
+		if (opcode == HCI_OP_RESET)
+			data->gp0_received = false;
+
 		hdev->stat.cmd_tx++;
 		break;
 	case HCI_ACLDATA_PKT:
@@ -1357,7 +1361,6 @@ static int btintel_pcie_send_frame(struct hci_dev *hdev,
 			   opcode, btintel_pcie_alivectxt_state2str(old_ctxt),
 			   btintel_pcie_alivectxt_state2str(data->alive_intr_ctxt));
 		if (opcode == HCI_OP_RESET) {
-			data->gp0_received = false;
 			ret = wait_event_timeout(data->gp0_wait_q,
 						 data->gp0_received,
 						 msecs_to_jiffies(BTINTEL_DEFAULT_INTR_TIMEOUT_MS));
-- 
2.51.0


From ab4eedb790cae44313759b50fe47da285e2519d5 Mon Sep 17 00:00:00 2001
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Thu, 6 Feb 2025 15:54:45 -0500
Subject: [PATCH 06/16] Bluetooth: L2CAP: Fix corrupted list in hci_chan_del

This fixes the following trace by reworking the locking of l2cap_conn
so instead of only locking when changing the chan_l list this promotes
chan_lock to a general lock of l2cap_conn so whenever it is being held
it would prevents the likes of l2cap_conn_del to run:

list_del corruption, ffff888021297e00->prev is LIST_POISON2 (dead000000000122)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:61!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 5896 Comm: syz-executor213 Not tainted 6.14.0-rc1-next-20250204-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:__list_del_entry_valid_or_report+0x12c/0x190 lib/list_debug.c:59
Code: 8c 4c 89 fe 48 89 da e8 32 8c 37 fc 90 0f 0b 48 89 df e8 27 9f 14 fd 48 c7 c7 a0 c0 60 8c 4c 89 fe 48 89 da e8 15 8c 37 fc 90 <0f> 0b 4c 89 e7 e8 0a 9f 14 fd 42 80 3c 2b 00 74 08 4c 89 e7 e8 cb
RSP: 0018:ffffc90003f6f998 EFLAGS: 00010246
RAX: 000000000000004e RBX: dead000000000122 RCX: 01454d423f7fbf00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff819f077c R09: 1ffff920007eded0
R10: dffffc0000000000 R11: fffff520007eded1 R12: dead000000000122
R13: dffffc0000000000 R14: ffff8880352248d8 R15: ffff888021297e00
FS:  00007f7ace6686c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7aceeeb1d0 CR3: 000000003527c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_del_entry_valid include/linux/list.h:124 [inline]
 __list_del_entry include/linux/list.h:215 [inline]
 list_del_rcu include/linux/rculist.h:168 [inline]
 hci_chan_del+0x70/0x1b0 net/bluetooth/hci_conn.c:2858
 l2cap_conn_free net/bluetooth/l2cap_core.c:1816 [inline]
 kref_put include/linux/kref.h:65 [inline]
 l2cap_conn_put+0x70/0xe0 net/bluetooth/l2cap_core.c:1830
 l2cap_sock_shutdown+0xa8a/0x1020 net/bluetooth/l2cap_sock.c:1377
 l2cap_sock_release+0x79/0x1d0 net/bluetooth/l2cap_sock.c:1416
 __sock_release net/socket.c:642 [inline]
 sock_close+0xbc/0x240 net/socket.c:1393
 __fput+0x3e9/0x9f0 fs/file_table.c:448
 task_work_run+0x24f/0x310 kernel/task_work.c:227
 ptrace_notify+0x2d2/0x380 kernel/signal.c:2522
 ptrace_report_syscall include/linux/ptrace.h:415 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline]
 syscall_exit_work+0xc7/0x1d0 kernel/entry/common.c:173
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline]
 syscall_exit_to_user_mode+0x24a/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7aceeaf449
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7ace668218 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffffc RBX: 00007f7acef39328 RCX: 00007f7aceeaf449
RDX: 000000000000000e RSI: 0000000020000100 RDI: 0000000000000004
RBP: 00007f7acef39320 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000004 R14: 00007f7ace668670 R15: 000000000000000b
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid_or_report+0x12c/0x190 lib/list_debug.c:59
Code: 8c 4c 89 fe 48 89 da e8 32 8c 37 fc 90 0f 0b 48 89 df e8 27 9f 14 fd 48 c7 c7 a0 c0 60 8c 4c 89 fe 48 89 da e8 15 8c 37 fc 90 <0f> 0b 4c 89 e7 e8 0a 9f 14 fd 42 80 3c 2b 00 74 08 4c 89 e7 e8 cb
RSP: 0018:ffffc90003f6f998 EFLAGS: 00010246
RAX: 000000000000004e RBX: dead000000000122 RCX: 01454d423f7fbf00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff819f077c R09: 1ffff920007eded0
R10: dffffc0000000000 R11: fffff520007eded1 R12: dead000000000122
R13: dffffc0000000000 R14: ffff8880352248d8 R15: ffff888021297e00
FS:  00007f7ace6686c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7acef05b08 CR3: 000000003527c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Reported-by: syzbot+10bd8fe6741eedd2be2e@syzkaller.appspotmail.com
Tested-by: syzbot+10bd8fe6741eedd2be2e@syzkaller.appspotmail.com
Fixes: b4f82f9ed43a ("Bluetooth: L2CAP: Fix slab-use-after-free Read in l2cap_send_cmd")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 include/net/bluetooth/l2cap.h |   3 +-
 net/bluetooth/l2cap_core.c    | 138 ++++++++++++----------------------
 net/bluetooth/l2cap_sock.c    |  15 ++--
 3 files changed, 58 insertions(+), 98 deletions(-)

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index d9c767cf773d..9189354c568f 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -668,7 +668,7 @@ struct l2cap_conn {
 	struct l2cap_chan	*smp;
 
 	struct list_head	chan_l;
-	struct mutex		chan_lock;
+	struct mutex		lock;
 	struct kref		ref;
 	struct list_head	users;
 };
@@ -970,6 +970,7 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err);
 void l2cap_send_conn_req(struct l2cap_chan *chan);
 
 struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn);
+struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *conn);
 void l2cap_conn_put(struct l2cap_conn *conn);
 
 int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user);
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index adb8c33ac595..fec11e576f31 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -119,7 +119,6 @@ static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
 {
 	struct l2cap_chan *c;
 
-	mutex_lock(&conn->chan_lock);
 	c = __l2cap_get_chan_by_scid(conn, cid);
 	if (c) {
 		/* Only lock if chan reference is not 0 */
@@ -127,7 +126,6 @@ static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
 		if (c)
 			l2cap_chan_lock(c);
 	}
-	mutex_unlock(&conn->chan_lock);
 
 	return c;
 }
@@ -140,7 +138,6 @@ static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
 {
 	struct l2cap_chan *c;
 
-	mutex_lock(&conn->chan_lock);
 	c = __l2cap_get_chan_by_dcid(conn, cid);
 	if (c) {
 		/* Only lock if chan reference is not 0 */
@@ -148,7 +145,6 @@ static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
 		if (c)
 			l2cap_chan_lock(c);
 	}
-	mutex_unlock(&conn->chan_lock);
 
 	return c;
 }
@@ -418,7 +414,7 @@ static void l2cap_chan_timeout(struct work_struct *work)
 	if (!conn)
 		return;
 
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 	/* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling
 	 * this work. No need to call l2cap_chan_hold(chan) here again.
 	 */
@@ -439,7 +435,7 @@ static void l2cap_chan_timeout(struct work_struct *work)
 	l2cap_chan_unlock(chan);
 	l2cap_chan_put(chan);
 
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 }
 
 struct l2cap_chan *l2cap_chan_create(void)
@@ -641,9 +637,9 @@ void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 
 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 {
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 	__l2cap_chan_add(conn, chan);
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 }
 
 void l2cap_chan_del(struct l2cap_chan *chan, int err)
@@ -731,9 +727,9 @@ void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
 	if (!conn)
 		return;
 
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 	__l2cap_chan_list(conn, func, data);
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 }
 
 EXPORT_SYMBOL_GPL(l2cap_chan_list);
@@ -745,7 +741,7 @@ static void l2cap_conn_update_id_addr(struct work_struct *work)
 	struct hci_conn *hcon = conn->hcon;
 	struct l2cap_chan *chan;
 
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 
 	list_for_each_entry(chan, &conn->chan_l, list) {
 		l2cap_chan_lock(chan);
@@ -754,7 +750,7 @@ static void l2cap_conn_update_id_addr(struct work_struct *work)
 		l2cap_chan_unlock(chan);
 	}
 
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 }
 
 static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
@@ -1507,8 +1503,6 @@ static void l2cap_conn_start(struct l2cap_conn *conn)
 
 	BT_DBG("conn %p", conn);
 
-	mutex_lock(&conn->chan_lock);
-
 	list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
 		l2cap_chan_lock(chan);
 
@@ -1577,8 +1571,6 @@ static void l2cap_conn_start(struct l2cap_conn *conn)
 
 		l2cap_chan_unlock(chan);
 	}
-
-	mutex_unlock(&conn->chan_lock);
 }
 
 static void l2cap_le_conn_ready(struct l2cap_conn *conn)
@@ -1624,7 +1616,7 @@ static void l2cap_conn_ready(struct l2cap_conn *conn)
 	if (hcon->type == ACL_LINK)
 		l2cap_request_info(conn);
 
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 
 	list_for_each_entry(chan, &conn->chan_l, list) {
 
@@ -1642,7 +1634,7 @@ static void l2cap_conn_ready(struct l2cap_conn *conn)
 		l2cap_chan_unlock(chan);
 	}
 
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 
 	if (hcon->type == LE_LINK)
 		l2cap_le_conn_ready(conn);
@@ -1657,14 +1649,10 @@ static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
 
 	BT_DBG("conn %p", conn);
 
-	mutex_lock(&conn->chan_lock);
-
 	list_for_each_entry(chan, &conn->chan_l, list) {
 		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
 			l2cap_chan_set_err(chan, err);
 	}
-
-	mutex_unlock(&conn->chan_lock);
 }
 
 static void l2cap_info_timeout(struct work_struct *work)
@@ -1675,7 +1663,9 @@ static void l2cap_info_timeout(struct work_struct *work)
 	conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
 	conn->info_ident = 0;
 
+	mutex_lock(&conn->lock);
 	l2cap_conn_start(conn);
+	mutex_unlock(&conn->lock);
 }
 
 /*
@@ -1767,6 +1757,8 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 
 	BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
 
+	mutex_lock(&conn->lock);
+
 	kfree_skb(conn->rx_skb);
 
 	skb_queue_purge(&conn->pending_rx);
@@ -1785,8 +1777,6 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 	/* Force the connection to be immediately dropped */
 	hcon->disc_timeout = 0;
 
-	mutex_lock(&conn->chan_lock);
-
 	/* Kill channels */
 	list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
 		l2cap_chan_hold(chan);
@@ -1800,12 +1790,14 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 		l2cap_chan_put(chan);
 	}
 
-	mutex_unlock(&conn->chan_lock);
-
 	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
 		cancel_delayed_work_sync(&conn->info_timer);
 
+	hci_chan_del(conn->hchan);
+	conn->hchan = NULL;
+
 	hcon->l2cap_data = NULL;
+	mutex_unlock(&conn->lock);
 	l2cap_conn_put(conn);
 }
 
@@ -1813,7 +1805,6 @@ static void l2cap_conn_free(struct kref *ref)
 {
 	struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
 
-	hci_chan_del(conn->hchan);
 	hci_conn_put(conn->hcon);
 	kfree(conn);
 }
@@ -2924,8 +2915,6 @@ static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
 
 	BT_DBG("conn %p", conn);
 
-	mutex_lock(&conn->chan_lock);
-
 	list_for_each_entry(chan, &conn->chan_l, list) {
 		if (chan->chan_type != L2CAP_CHAN_RAW)
 			continue;
@@ -2940,8 +2929,6 @@ static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
 		if (chan->ops->recv(chan, nskb))
 			kfree_skb(nskb);
 	}
-
-	mutex_unlock(&conn->chan_lock);
 }
 
 /* ---- L2CAP signalling commands ---- */
@@ -3960,7 +3947,6 @@ static void l2cap_connect(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd,
 		goto response;
 	}
 
-	mutex_lock(&conn->chan_lock);
 	l2cap_chan_lock(pchan);
 
 	/* Check if the ACL is secure enough (if not SDP) */
@@ -4067,7 +4053,6 @@ response:
 	}
 
 	l2cap_chan_unlock(pchan);
-	mutex_unlock(&conn->chan_lock);
 	l2cap_chan_put(pchan);
 }
 
@@ -4106,27 +4091,19 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
 	BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
 	       dcid, scid, result, status);
 
-	mutex_lock(&conn->chan_lock);
-
 	if (scid) {
 		chan = __l2cap_get_chan_by_scid(conn, scid);
-		if (!chan) {
-			err = -EBADSLT;
-			goto unlock;
-		}
+		if (!chan)
+			return -EBADSLT;
 	} else {
 		chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
-		if (!chan) {
-			err = -EBADSLT;
-			goto unlock;
-		}
+		if (!chan)
+			return -EBADSLT;
 	}
 
 	chan = l2cap_chan_hold_unless_zero(chan);
-	if (!chan) {
-		err = -EBADSLT;
-		goto unlock;
-	}
+	if (!chan)
+		return -EBADSLT;
 
 	err = 0;
 
@@ -4164,9 +4141,6 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
 	l2cap_chan_unlock(chan);
 	l2cap_chan_put(chan);
 
-unlock:
-	mutex_unlock(&conn->chan_lock);
-
 	return err;
 }
 
@@ -4454,11 +4428,7 @@ static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
 
 	chan->ops->set_shutdown(chan);
 
-	l2cap_chan_unlock(chan);
-	mutex_lock(&conn->chan_lock);
-	l2cap_chan_lock(chan);
 	l2cap_chan_del(chan, ECONNRESET);
-	mutex_unlock(&conn->chan_lock);
 
 	chan->ops->close(chan);
 
@@ -4495,11 +4465,7 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
 		return 0;
 	}
 
-	l2cap_chan_unlock(chan);
-	mutex_lock(&conn->chan_lock);
-	l2cap_chan_lock(chan);
 	l2cap_chan_del(chan, 0);
-	mutex_unlock(&conn->chan_lock);
 
 	chan->ops->close(chan);
 
@@ -4697,13 +4663,9 @@ static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
 	BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
 	       dcid, mtu, mps, credits, result);
 
-	mutex_lock(&conn->chan_lock);
-
 	chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
-	if (!chan) {
-		err = -EBADSLT;
-		goto unlock;
-	}
+	if (!chan)
+		return -EBADSLT;
 
 	err = 0;
 
@@ -4751,9 +4713,6 @@ static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
 
 	l2cap_chan_unlock(chan);
 
-unlock:
-	mutex_unlock(&conn->chan_lock);
-
 	return err;
 }
 
@@ -4865,7 +4824,6 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn,
 		goto response;
 	}
 
-	mutex_lock(&conn->chan_lock);
 	l2cap_chan_lock(pchan);
 
 	if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
@@ -4931,7 +4889,6 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn,
 
 response_unlock:
 	l2cap_chan_unlock(pchan);
-	mutex_unlock(&conn->chan_lock);
 	l2cap_chan_put(pchan);
 
 	if (result == L2CAP_CR_PEND)
@@ -5065,7 +5022,6 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
 		goto response;
 	}
 
-	mutex_lock(&conn->chan_lock);
 	l2cap_chan_lock(pchan);
 
 	if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
@@ -5140,7 +5096,6 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
 
 unlock:
 	l2cap_chan_unlock(pchan);
-	mutex_unlock(&conn->chan_lock);
 	l2cap_chan_put(pchan);
 
 response:
@@ -5177,8 +5132,6 @@ static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn,
 	BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits,
 	       result);
 
-	mutex_lock(&conn->chan_lock);
-
 	cmd_len -= sizeof(*rsp);
 
 	list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
@@ -5264,8 +5217,6 @@ static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn,
 		l2cap_chan_unlock(chan);
 	}
 
-	mutex_unlock(&conn->chan_lock);
-
 	return err;
 }
 
@@ -5378,8 +5329,6 @@ static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
 	if (cmd_len < sizeof(*rej))
 		return -EPROTO;
 
-	mutex_lock(&conn->chan_lock);
-
 	chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
 	if (!chan)
 		goto done;
@@ -5394,7 +5343,6 @@ static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
 	l2cap_chan_put(chan);
 
 done:
-	mutex_unlock(&conn->chan_lock);
 	return 0;
 }
 
@@ -6849,8 +6797,12 @@ static void process_pending_rx(struct work_struct *work)
 
 	BT_DBG("");
 
+	mutex_lock(&conn->lock);
+
 	while ((skb = skb_dequeue(&conn->pending_rx)))
 		l2cap_recv_frame(conn, skb);
+
+	mutex_unlock(&conn->lock);
 }
 
 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
@@ -6889,7 +6841,7 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
 		conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
 
 	mutex_init(&conn->ident_lock);
-	mutex_init(&conn->chan_lock);
+	mutex_init(&conn->lock);
 
 	INIT_LIST_HEAD(&conn->chan_l);
 	INIT_LIST_HEAD(&conn->users);
@@ -7080,7 +7032,7 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 		}
 	}
 
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 	l2cap_chan_lock(chan);
 
 	if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
@@ -7121,7 +7073,7 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 
 chan_unlock:
 	l2cap_chan_unlock(chan);
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 done:
 	hci_dev_unlock(hdev);
 	hci_dev_put(hdev);
@@ -7333,7 +7285,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
 
 	BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
 
-	mutex_lock(&conn->chan_lock);
+	mutex_lock(&conn->lock);
 
 	list_for_each_entry(chan, &conn->chan_l, list) {
 		l2cap_chan_lock(chan);
@@ -7407,7 +7359,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
 		l2cap_chan_unlock(chan);
 	}
 
-	mutex_unlock(&conn->chan_lock);
+	mutex_unlock(&conn->lock);
 }
 
 /* Append fragment into frame respecting the maximum len of rx_skb */
@@ -7474,8 +7426,11 @@ static void l2cap_recv_reset(struct l2cap_conn *conn)
 	conn->rx_len = 0;
 }
 
-static struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c)
+struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c)
 {
+	if (!c)
+		return NULL;
+
 	BT_DBG("conn %p orig refcnt %u", c, kref_read(&c->ref));
 
 	if (!kref_get_unless_zero(&c->ref))
@@ -7501,11 +7456,15 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 
 	hci_dev_unlock(hcon->hdev);
 
-	if (!conn)
-		goto drop;
+	if (!conn) {
+		kfree_skb(skb);
+		return;
+	}
 
 	BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags);
 
+	mutex_lock(&conn->lock);
+
 	switch (flags) {
 	case ACL_START:
 	case ACL_START_NO_FLUSH:
@@ -7530,7 +7489,7 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 		if (len == skb->len) {
 			/* Complete frame received */
 			l2cap_recv_frame(conn, skb);
-			return;
+			goto unlock;
 		}
 
 		BT_DBG("Start: total len %d, frag len %u", len, skb->len);
@@ -7592,10 +7551,11 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 		break;
 	}
 
-	l2cap_conn_put(conn);
-
 drop:
 	kfree_skb(skb);
+unlock:
+	mutex_unlock(&conn->lock);
+	l2cap_conn_put(conn);
 }
 
 static struct hci_cb l2cap_cb = {
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 46ea0bee2259..acd11b268b98 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1326,9 +1326,10 @@ static int l2cap_sock_shutdown(struct socket *sock, int how)
 	/* prevent sk structure from being freed whilst unlocked */
 	sock_hold(sk);
 
-	chan = l2cap_pi(sk)->chan;
 	/* prevent chan structure from being freed whilst unlocked */
-	l2cap_chan_hold(chan);
+	chan = l2cap_chan_hold_unless_zero(l2cap_pi(sk)->chan);
+	if (!chan)
+		goto shutdown_already;
 
 	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
 
@@ -1358,22 +1359,20 @@ static int l2cap_sock_shutdown(struct socket *sock, int how)
 	release_sock(sk);
 
 	l2cap_chan_lock(chan);
-	conn = chan->conn;
-	if (conn)
-		/* prevent conn structure from being freed */
-		l2cap_conn_get(conn);
+	/* prevent conn structure from being freed */
+	conn = l2cap_conn_hold_unless_zero(chan->conn);
 	l2cap_chan_unlock(chan);
 
 	if (conn)
 		/* mutex lock must be taken before l2cap_chan_lock() */
-		mutex_lock(&conn->chan_lock);
+		mutex_lock(&conn->lock);
 
 	l2cap_chan_lock(chan);
 	l2cap_chan_close(chan, 0);
 	l2cap_chan_unlock(chan);
 
 	if (conn) {
-		mutex_unlock(&conn->chan_lock);
+		mutex_unlock(&conn->lock);
 		l2cap_conn_put(conn);
 	}
 
-- 
2.51.0


From 5bef3ac184b5626ea62385d6b82a1992b89d7940 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Wed, 12 Feb 2025 13:49:28 +0000
Subject: [PATCH 07/16] team: better TEAM_OPTION_TYPE_STRING validation

syzbot reported following splat [1]

Make sure user-provided data contains one nul byte.

[1]
 BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:633 [inline]
 BUG: KMSAN: uninit-value in string+0x3ec/0x5f0 lib/vsprintf.c:714
  string_nocheck lib/vsprintf.c:633 [inline]
  string+0x3ec/0x5f0 lib/vsprintf.c:714
  vsnprintf+0xa5d/0x1960 lib/vsprintf.c:2843
  __request_module+0x252/0x9f0 kernel/module/kmod.c:149
  team_mode_get drivers/net/team/team_core.c:480 [inline]
  team_change_mode drivers/net/team/team_core.c:607 [inline]
  team_mode_option_set+0x437/0x970 drivers/net/team/team_core.c:1401
  team_option_set drivers/net/team/team_core.c:375 [inline]
  team_nl_options_set_doit+0x1339/0x1f90 drivers/net/team/team_core.c:2662
  genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
  genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
  genl_rcv_msg+0x1214/0x12c0 net/netlink/genetlink.c:1210
  netlink_rcv_skb+0x375/0x650 net/netlink/af_netlink.c:2543
  genl_rcv+0x40/0x60 net/netlink/genetlink.c:1219
  netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
  netlink_unicast+0xf52/0x1260 net/netlink/af_netlink.c:1348
  netlink_sendmsg+0x10da/0x11e0 net/netlink/af_netlink.c:1892
  sock_sendmsg_nosec net/socket.c:718 [inline]
  __sock_sendmsg+0x30f/0x380 net/socket.c:733
  ____sys_sendmsg+0x877/0xb60 net/socket.c:2573
  ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2627
  __sys_sendmsg net/socket.c:2659 [inline]
  __do_sys_sendmsg net/socket.c:2664 [inline]
  __se_sys_sendmsg net/socket.c:2662 [inline]
  __x64_sys_sendmsg+0x212/0x3c0 net/socket.c:2662
  x64_sys_call+0x2ed6/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:47
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device")
Reported-by: syzbot+1fcd957a82e3a1baa94d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1fcd957a82e3a1baa94d
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20250212134928.1541609-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/team/team_core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c
index dc7cbd6a9798..f4019815f473 100644
--- a/drivers/net/team/team_core.c
+++ b/drivers/net/team/team_core.c
@@ -2639,7 +2639,9 @@ int team_nl_options_set_doit(struct sk_buff *skb, struct genl_info *info)
 				ctx.data.u32_val = nla_get_u32(attr_data);
 				break;
 			case TEAM_OPTION_TYPE_STRING:
-				if (nla_len(attr_data) > TEAM_STRING_MAX_LEN) {
+				if (nla_len(attr_data) > TEAM_STRING_MAX_LEN ||
+				    !memchr(nla_data(attr_data), '\0',
+					    nla_len(attr_data))) {
 					err = -EINVAL;
 					goto team_put;
 				}
-- 
2.51.0


From a527750d877fd334de87eef81f1cb5f0f0ca3373 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Wed, 12 Feb 2025 14:10:21 +0000
Subject: [PATCH 08/16] ipv6: mcast: add RCU protection to mld_newpack()

mld_newpack() can be called without RTNL or RCU being held.

Note that we no longer can use sock_alloc_send_skb() because
ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.

Instead use alloc_skb() and charge the net->ipv6.igmp_sk
socket under RCU protection.

Fixes: b8ad0cbc58f7 ("[NETNS][IPV6] mcast - handle several network namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250212141021.1663666-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 net/ipv6/mcast.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 81a739ebf709..65831b4fee1f 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1773,21 +1773,19 @@ static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
 	struct net_device *dev = idev->dev;
 	int hlen = LL_RESERVED_SPACE(dev);
 	int tlen = dev->needed_tailroom;
-	struct net *net = dev_net(dev);
 	const struct in6_addr *saddr;
 	struct in6_addr addr_buf;
 	struct mld2_report *pmr;
 	struct sk_buff *skb;
 	unsigned int size;
 	struct sock *sk;
-	int err;
+	struct net *net;
 
-	sk = net->ipv6.igmp_sk;
 	/* we assume size > sizeof(ra) here
 	 * Also try to not allocate high-order pages for big MTU
 	 */
 	size = min_t(int, mtu, PAGE_SIZE / 2) + hlen + tlen;
-	skb = sock_alloc_send_skb(sk, size, 1, &err);
+	skb = alloc_skb(size, GFP_KERNEL);
 	if (!skb)
 		return NULL;
 
@@ -1795,6 +1793,12 @@ static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
 	skb_reserve(skb, hlen);
 	skb_tailroom_reserve(skb, mtu, tlen);
 
+	rcu_read_lock();
+
+	net = dev_net_rcu(dev);
+	sk = net->ipv6.igmp_sk;
+	skb_set_owner_w(skb, sk);
+
 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
 		/* <draft-ietf-magma-mld-source-05.txt>:
 		 * use unspecified address as the source address
@@ -1806,6 +1810,8 @@ static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
 
 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
 
+	rcu_read_unlock();
+
 	skb_put_data(skb, ra, sizeof(ra));
 
 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
-- 
2.51.0


From fee5d688940690cc845937459e340e4e02598e90 Mon Sep 17 00:00:00 2001
From: Wentao Liang <vulab@iscas.ac.cn>
Date: Wed, 12 Feb 2025 23:23:11 +0800
Subject: [PATCH 09/16] mlxsw: Add return value check for
 mlxsw_sp_port_get_stats_raw()

Add a check for the return value of mlxsw_sp_port_get_stats_raw()
in __mlxsw_sp_port_get_stats(). If mlxsw_sp_port_get_stats_raw()
returns an error, exit the function to prevent further processing
with potentially invalid data.

Fixes: 614d509aa1e7 ("mlxsw: Move ethtool_ops to spectrum_ethtool.c")
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Link: https://patch.msgid.link/20250212152311.1332-1-vulab@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_ethtool.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ethtool.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ethtool.c
index 2bed8c86b7cf..3f64cdbabfa3 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ethtool.c
@@ -768,7 +768,9 @@ static void __mlxsw_sp_port_get_stats(struct net_device *dev,
 	err = mlxsw_sp_get_hw_stats_by_group(&hw_stats, &len, grp);
 	if (err)
 		return;
-	mlxsw_sp_port_get_stats_raw(dev, grp, prio, ppcnt_pl);
+	err = mlxsw_sp_port_get_stats_raw(dev, grp, prio, ppcnt_pl);
+	if (err)
+		return;
 	for (i = 0; i < len; i++) {
 		data[data_index + i] = hw_stats[i].getter(ppcnt_pl);
 		if (!hw_stats[i].cells_bytes)
-- 
2.51.0


From 0d0b752f2497471ddd2b32143d167d42e18a8f3c Mon Sep 17 00:00:00 2001
From: Alexandra Winter <wintera@linux.ibm.com>
Date: Wed, 12 Feb 2025 17:36:59 +0100
Subject: [PATCH 10/16] s390/qeth: move netif_napi_add_tx() and napi_enable()
 from under BH

Like other drivers qeth is calling local_bh_enable() after napi_schedule()
to kick-start softirqs [0].
Since netif_napi_add_tx() and napi_enable() now take the netdev_lock()
mutex [1], move them out from under the BH protection. Same solution as in
commit a60558644e20 ("wifi: mt76: move napi_enable() from under BH")

Fixes: 1b23cdbd2bbc ("net: protect netdev->napi_list with netdev_lock()")
Link: https://lore.kernel.org/netdev/20240612181900.4d9d18d0@kernel.org/ [0]
Link: https://lore.kernel.org/netdev/20250115035319.559603-1-kuba@kernel.org/ [1]
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Acked-by: Joe Damato <jdamato@fastly.com>
Link: https://patch.msgid.link/20250212163659.2287292-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/s390/net/qeth_core_main.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index a3adaec5504e..20328d695ef9 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -7050,14 +7050,16 @@ int qeth_open(struct net_device *dev)
 	card->data.state = CH_STATE_UP;
 	netif_tx_start_all_queues(dev);
 
-	local_bh_disable();
 	qeth_for_each_output_queue(card, queue, i) {
 		netif_napi_add_tx(dev, &queue->napi, qeth_tx_poll);
 		napi_enable(&queue->napi);
-		napi_schedule(&queue->napi);
 	}
-
 	napi_enable(&card->napi);
+
+	local_bh_disable();
+	qeth_for_each_output_queue(card, queue, i) {
+		napi_schedule(&queue->napi);
+	}
 	napi_schedule(&card->napi);
 	/* kick-start the NAPI softirq: */
 	local_bh_enable();
-- 
2.51.0


From 0892b840318daa6ae739b7cdec5ecdfca4006689 Mon Sep 17 00:00:00 2001
From: Jakub Kicinski <kuba@kernel.org>
Date: Thu, 13 Feb 2025 08:49:44 -0800
Subject: [PATCH 11/16] Reapply "net: skb: introduce and use a single page frag
 cache"

This reverts commit 011b0335903832facca86cd8ed05d7d8d94c9c76.

Sabrina reports that the revert may trigger warnings due to intervening
changes, especially the ability to rise MAX_SKB_FRAGS. Let's drop it
and revisit once that part is also ironed out.

Fixes: 011b03359038 ("Revert "net: skb: introduce and use a single page frag cache"")
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/6bf54579233038bc0e76056c5ea459872ce362ab.1739375933.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 include/linux/netdevice.h |   1 +
 net/core/dev.c            |  17 -------
 net/core/skbuff.c         | 103 ++++++++++++++++++++++++++++++++++++--
 3 files changed, 99 insertions(+), 22 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 365f0e2098d1..c0a86afb85da 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4115,6 +4115,7 @@ void netif_receive_skb_list(struct list_head *head);
 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb);
 void napi_gro_flush(struct napi_struct *napi, bool flush_old);
 struct sk_buff *napi_get_frags(struct napi_struct *napi);
+void napi_get_frags_check(struct napi_struct *napi);
 gro_result_t napi_gro_frags(struct napi_struct *napi);
 
 static inline void napi_free_frags(struct napi_struct *napi)
diff --git a/net/core/dev.c b/net/core/dev.c
index 55e356a68db6..b91658e8aedb 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6920,23 +6920,6 @@ netif_napi_dev_list_add(struct net_device *dev, struct napi_struct *napi)
 	list_add_rcu(&napi->dev_list, higher); /* adds after higher */
 }
 
-/* Double check that napi_get_frags() allocates skbs with
- * skb->head being backed by slab, not a page fragment.
- * This is to make sure bug fixed in 3226b158e67c
- * ("net: avoid 32 x truesize under-estimation for tiny skbs")
- * does not accidentally come back.
- */
-static void napi_get_frags_check(struct napi_struct *napi)
-{
-	struct sk_buff *skb;
-
-	local_bh_disable();
-	skb = napi_get_frags(napi);
-	WARN_ON_ONCE(skb && skb->head_frag);
-	napi_free_frags(napi);
-	local_bh_enable();
-}
-
 void netif_napi_add_weight_locked(struct net_device *dev,
 				  struct napi_struct *napi,
 				  int (*poll)(struct napi_struct *, int),
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 6a99c453397f..a441613a1e6c 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -220,9 +220,67 @@ static void skb_under_panic(struct sk_buff *skb, unsigned int sz, void *addr)
 #define NAPI_SKB_CACHE_BULK	16
 #define NAPI_SKB_CACHE_HALF	(NAPI_SKB_CACHE_SIZE / 2)
 
+#if PAGE_SIZE == SZ_4K
+
+#define NAPI_HAS_SMALL_PAGE_FRAG	1
+#define NAPI_SMALL_PAGE_PFMEMALLOC(nc)	((nc).pfmemalloc)
+
+/* specialized page frag allocator using a single order 0 page
+ * and slicing it into 1K sized fragment. Constrained to systems
+ * with a very limited amount of 1K fragments fitting a single
+ * page - to avoid excessive truesize underestimation
+ */
+
+struct page_frag_1k {
+	void *va;
+	u16 offset;
+	bool pfmemalloc;
+};
+
+static void *page_frag_alloc_1k(struct page_frag_1k *nc, gfp_t gfp)
+{
+	struct page *page;
+	int offset;
+
+	offset = nc->offset - SZ_1K;
+	if (likely(offset >= 0))
+		goto use_frag;
+
+	page = alloc_pages_node(NUMA_NO_NODE, gfp, 0);
+	if (!page)
+		return NULL;
+
+	nc->va = page_address(page);
+	nc->pfmemalloc = page_is_pfmemalloc(page);
+	offset = PAGE_SIZE - SZ_1K;
+	page_ref_add(page, offset / SZ_1K);
+
+use_frag:
+	nc->offset = offset;
+	return nc->va + offset;
+}
+#else
+
+/* the small page is actually unused in this build; add dummy helpers
+ * to please the compiler and avoid later preprocessor's conditionals
+ */
+#define NAPI_HAS_SMALL_PAGE_FRAG	0
+#define NAPI_SMALL_PAGE_PFMEMALLOC(nc)	false
+
+struct page_frag_1k {
+};
+
+static void *page_frag_alloc_1k(struct page_frag_1k *nc, gfp_t gfp_mask)
+{
+	return NULL;
+}
+
+#endif
+
 struct napi_alloc_cache {
 	local_lock_t bh_lock;
 	struct page_frag_cache page;
+	struct page_frag_1k page_small;
 	unsigned int skb_count;
 	void *skb_cache[NAPI_SKB_CACHE_SIZE];
 };
@@ -232,6 +290,23 @@ static DEFINE_PER_CPU(struct napi_alloc_cache, napi_alloc_cache) = {
 	.bh_lock = INIT_LOCAL_LOCK(bh_lock),
 };
 
+/* Double check that napi_get_frags() allocates skbs with
+ * skb->head being backed by slab, not a page fragment.
+ * This is to make sure bug fixed in 3226b158e67c
+ * ("net: avoid 32 x truesize under-estimation for tiny skbs")
+ * does not accidentally come back.
+ */
+void napi_get_frags_check(struct napi_struct *napi)
+{
+	struct sk_buff *skb;
+
+	local_bh_disable();
+	skb = napi_get_frags(napi);
+	WARN_ON_ONCE(!NAPI_HAS_SMALL_PAGE_FRAG && skb && skb->head_frag);
+	napi_free_frags(napi);
+	local_bh_enable();
+}
+
 void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
 {
 	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
@@ -738,8 +813,10 @@ struct sk_buff *napi_alloc_skb(struct napi_struct *napi, unsigned int len)
 
 	/* If requested length is either too small or too big,
 	 * we use kmalloc() for skb->head allocation.
+	 * When the small frag allocator is available, prefer it over kmalloc
+	 * for small fragments
 	 */
-	if (len <= SKB_WITH_OVERHEAD(1024) ||
+	if ((!NAPI_HAS_SMALL_PAGE_FRAG && len <= SKB_WITH_OVERHEAD(1024)) ||
 	    len > SKB_WITH_OVERHEAD(PAGE_SIZE) ||
 	    (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) {
 		skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX | SKB_ALLOC_NAPI,
@@ -749,16 +826,32 @@ struct sk_buff *napi_alloc_skb(struct napi_struct *napi, unsigned int len)
 		goto skb_success;
 	}
 
-	len = SKB_HEAD_ALIGN(len);
-
 	if (sk_memalloc_socks())
 		gfp_mask |= __GFP_MEMALLOC;
 
 	local_lock_nested_bh(&napi_alloc_cache.bh_lock);
 	nc = this_cpu_ptr(&napi_alloc_cache);
+	if (NAPI_HAS_SMALL_PAGE_FRAG && len <= SKB_WITH_OVERHEAD(1024)) {
+		/* we are artificially inflating the allocation size, but
+		 * that is not as bad as it may look like, as:
+		 * - 'len' less than GRO_MAX_HEAD makes little sense
+		 * - On most systems, larger 'len' values lead to fragment
+		 *   size above 512 bytes
+		 * - kmalloc would use the kmalloc-1k slab for such values
+		 * - Builds with smaller GRO_MAX_HEAD will very likely do
+		 *   little networking, as that implies no WiFi and no
+		 *   tunnels support, and 32 bits arches.
+		 */
+		len = SZ_1K;
 
-	data = page_frag_alloc(&nc->page, len, gfp_mask);
-	pfmemalloc = page_frag_cache_is_pfmemalloc(&nc->page);
+		data = page_frag_alloc_1k(&nc->page_small, gfp_mask);
+		pfmemalloc = NAPI_SMALL_PAGE_PFMEMALLOC(nc->page_small);
+	} else {
+		len = SKB_HEAD_ALIGN(len);
+
+		data = page_frag_alloc(&nc->page, len, gfp_mask);
+		pfmemalloc = page_frag_cache_is_pfmemalloc(&nc->page);
+	}
 	local_unlock_nested_bh(&napi_alloc_cache.bh_lock);
 
 	if (unlikely(!data))
-- 
2.51.0


From 540cda75884a6ba4c289980c84392261b1f61a9c Mon Sep 17 00:00:00 2001
From: David Howells <dhowells@redhat.com>
Date: Wed, 12 Feb 2025 11:21:24 +0000
Subject: [PATCH 12/16] rxrpc: Fix ipv6 path MTU discovery

rxrpc path MTU discovery currently only makes use of ICMPv4, but not
ICMPv6, which means that pmtud for IPv6 doesn't work correctly.  Fix it to
check for ICMPv6 messages also.

Fixes: eeaedc5449d9 ("rxrpc: Implement path-MTU probing using padded PING ACKs (RFC8899)")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/3517283.1739359284@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 net/rxrpc/peer_event.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c
index e874c31fa901..bc283da9ee40 100644
--- a/net/rxrpc/peer_event.c
+++ b/net/rxrpc/peer_event.c
@@ -169,6 +169,13 @@ void rxrpc_input_error(struct rxrpc_local *local, struct sk_buff *skb)
 		goto out;
 	}
 
+	if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 &&
+	     serr->ee.ee_type == ICMPV6_PKT_TOOBIG &&
+	     serr->ee.ee_code == 0)) {
+		rxrpc_adjust_mtu(peer, serr->ee.ee_info);
+		goto out;
+	}
+
 	rxrpc_store_error(peer, skb);
 out:
 	rxrpc_put_peer(peer, rxrpc_peer_put_input_error);
-- 
2.51.0


From 488fb6effe03e20f38d34da7425de77bbd3e2665 Mon Sep 17 00:00:00 2001
From: Kory Maincent <kory.maincent@bootlin.com>
Date: Wed, 12 Feb 2025 16:17:51 +0100
Subject: [PATCH 13/16] net: pse-pd: Fix deadlock in current limit functions

Fix a deadlock in pse_pi_get_current_limit and pse_pi_set_current_limit
caused by consecutive mutex_lock calls. One in the function itself and
another in pse_pi_get_voltage.

Resolve the issue by using the unlocked version of pse_pi_get_voltage
instead.

Fixes: e0a5e2bba38a ("net: pse-pd: Use power limit at driver side instead of current limit")
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20250212151751.1515008-1-kory.maincent@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/pse-pd/pse_core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/pse-pd/pse_core.c b/drivers/net/pse-pd/pse_core.c
index 4f2a54afc4d0..4602e26eb8c8 100644
--- a/drivers/net/pse-pd/pse_core.c
+++ b/drivers/net/pse-pd/pse_core.c
@@ -319,7 +319,7 @@ static int pse_pi_get_current_limit(struct regulator_dev *rdev)
 		goto out;
 	mW = ret;
 
-	ret = pse_pi_get_voltage(rdev);
+	ret = _pse_pi_get_voltage(rdev);
 	if (!ret) {
 		dev_err(pcdev->dev, "Voltage null\n");
 		ret = -ERANGE;
@@ -356,7 +356,7 @@ static int pse_pi_set_current_limit(struct regulator_dev *rdev, int min_uA,
 
 	id = rdev_get_id(rdev);
 	mutex_lock(&pcdev->lock);
-	ret = pse_pi_get_voltage(rdev);
+	ret = _pse_pi_get_voltage(rdev);
 	if (!ret) {
 		dev_err(pcdev->dev, "Voltage null\n");
 		ret = -ERANGE;
-- 
2.51.0


From 77b823fa619f97d16409ca37ad4f7936e28c5f83 Mon Sep 17 00:00:00 2001
From: Ivan Kokshaysky <ink@unseen.parts>
Date: Tue, 4 Feb 2025 23:35:22 +0100
Subject: [PATCH 14/16] alpha: replace hardcoded stack offsets with
 autogenerated ones

This allows the assembly in entry.S to automatically keep in sync with
changes in the stack layout (struct pt_regs and struct switch_stack).

Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
---
 arch/alpha/kernel/asm-offsets.c | 4 ++++
 arch/alpha/kernel/entry.S       | 4 ----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/alpha/kernel/asm-offsets.c b/arch/alpha/kernel/asm-offsets.c
index 4cfeae42c79a..e9dad60b147f 100644
--- a/arch/alpha/kernel/asm-offsets.c
+++ b/arch/alpha/kernel/asm-offsets.c
@@ -19,9 +19,13 @@ static void __used foo(void)
 	DEFINE(TI_STATUS, offsetof(struct thread_info, status));
 	BLANK();
 
+	DEFINE(SP_OFF, offsetof(struct pt_regs, ps));
 	DEFINE(SIZEOF_PT_REGS, sizeof(struct pt_regs));
 	BLANK();
 
+	DEFINE(SWITCH_STACK_SIZE, sizeof(struct switch_stack));
+	BLANK();
+
 	DEFINE(HAE_CACHE, offsetof(struct alpha_machine_vector, hae_cache));
 	DEFINE(HAE_REG, offsetof(struct alpha_machine_vector, hae_register));
 }
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index dd26062d75b3..6fb38365539d 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -15,10 +15,6 @@
 	.set noat
 	.cfi_sections	.debug_frame
 
-/* Stack offsets.  */
-#define SP_OFF			184
-#define SWITCH_STACK_SIZE	64
-
 .macro	CFI_START_OSF_FRAME	func
 	.align	4
 	.globl	\func
-- 
2.51.0


From 0a0f7362b0367634a2d5cb7c96226afc116f19c9 Mon Sep 17 00:00:00 2001
From: Ivan Kokshaysky <ink@unseen.parts>
Date: Tue, 4 Feb 2025 23:35:23 +0100
Subject: [PATCH 15/16] alpha: make stack 16-byte aligned (most cases)

The problem is that GCC expects 16-byte alignment of the incoming stack
since early 2004, as Maciej found out [1]:
  Having actually dug speculatively I can see that the psABI was changed in
 GCC 3.5 with commit e5e10fb4a350 ("re PR target/14539 (128-bit long double
 improperly aligned)") back in Mar 2004, when the stack pointer alignment
 was increased from 8 bytes to 16 bytes, and arch/alpha/kernel/entry.S has
 various suspicious stack pointer adjustments, starting with SP_OFF which
 is not a whole multiple of 16.

Also, as Magnus noted, "ALPHA Calling Standard" [2] required the same:
 D.3.1 Stack Alignment
  This standard requires that stacks be octaword aligned at the time a
  new procedure is invoked.

However:
- the "normal" kernel stack is always misaligned by 8 bytes, thanks to
  the odd number of 64-bit words in 'struct pt_regs', which is the very
  first thing pushed onto the kernel thread stack;
- syscall, fault, interrupt etc. handlers may, or may not, receive aligned
  stack depending on numerous factors.

Somehow we got away with it until recently, when we ended up with
a stack corruption in kernel/smp.c:smp_call_function_single() due to
its use of 32-byte aligned local data and the compiler doing clever
things allocating it on the stack.

This adds padding between the PAL-saved and kernel-saved registers
so that 'struct pt_regs' have an even number of 64-bit words.
This makes the stack properly aligned for most of the kernel
code, except two handlers which need special threatment.

Note: struct pt_regs doesn't belong in uapi/asm; this should be fixed,
but let's put this off until later.

Link: https://lore.kernel.org/rcu/alpine.DEB.2.21.2501130248010.18889@angie.orcam.me.uk/ [1]
Link: https://bitsavers.org/pdf/dec/alpha/Alpha_Calling_Standard_Rev_2.0_19900427.pdf [2]

Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
---
 arch/alpha/include/uapi/asm/ptrace.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/alpha/include/uapi/asm/ptrace.h b/arch/alpha/include/uapi/asm/ptrace.h
index 5ca45934fcbb..72ed913a910f 100644
--- a/arch/alpha/include/uapi/asm/ptrace.h
+++ b/arch/alpha/include/uapi/asm/ptrace.h
@@ -42,6 +42,8 @@ struct pt_regs {
 	unsigned long trap_a0;
 	unsigned long trap_a1;
 	unsigned long trap_a2;
+/* This makes the stack 16-byte aligned as GCC expects */
+	unsigned long __pad0;
 /* These are saved by PAL-code: */
 	unsigned long ps;
 	unsigned long pc;
-- 
2.51.0


From 3b35a171060f846b08b48646b38c30b5d57d17ff Mon Sep 17 00:00:00 2001
From: Ivan Kokshaysky <ink@unseen.parts>
Date: Tue, 4 Feb 2025 23:35:24 +0100
Subject: [PATCH 16/16] alpha: align stack for page fault and user unaligned
 trap handlers

do_page_fault() and do_entUna() are special because they use
non-standard stack frame layout. Fix them manually.

Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
---
 arch/alpha/kernel/entry.S | 20 ++++++++++----------
 arch/alpha/kernel/traps.c |  2 +-
 arch/alpha/mm/fault.c     |  4 ++--
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index 6fb38365539d..f4d41b4538c2 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -194,8 +194,8 @@ CFI_END_OSF_FRAME entArith
 CFI_START_OSF_FRAME entMM
 	SAVE_ALL
 /* save $9 - $15 so the inline exception code can manipulate them.  */
-	subq	$sp, 56, $sp
-	.cfi_adjust_cfa_offset	56
+	subq	$sp, 64, $sp
+	.cfi_adjust_cfa_offset	64
 	stq	$9, 0($sp)
 	stq	$10, 8($sp)
 	stq	$11, 16($sp)
@@ -210,7 +210,7 @@ CFI_START_OSF_FRAME entMM
 	.cfi_rel_offset	$13, 32
 	.cfi_rel_offset	$14, 40
 	.cfi_rel_offset	$15, 48
-	addq	$sp, 56, $19
+	addq	$sp, 64, $19
 /* handle the fault */
 	lda	$8, 0x3fff
 	bic	$sp, $8, $8
@@ -223,7 +223,7 @@ CFI_START_OSF_FRAME entMM
 	ldq	$13, 32($sp)
 	ldq	$14, 40($sp)
 	ldq	$15, 48($sp)
-	addq	$sp, 56, $sp
+	addq	$sp, 64, $sp
 	.cfi_restore	$9
 	.cfi_restore	$10
 	.cfi_restore	$11
@@ -231,7 +231,7 @@ CFI_START_OSF_FRAME entMM
 	.cfi_restore	$13
 	.cfi_restore	$14
 	.cfi_restore	$15
-	.cfi_adjust_cfa_offset	-56
+	.cfi_adjust_cfa_offset	-64
 /* finish up the syscall as normal.  */
 	br	ret_from_sys_call
 CFI_END_OSF_FRAME entMM
@@ -378,8 +378,8 @@ entUnaUser:
 	.cfi_restore	$0
 	.cfi_adjust_cfa_offset	-256
 	SAVE_ALL		/* setup normal kernel stack */
-	lda	$sp, -56($sp)
-	.cfi_adjust_cfa_offset	56
+	lda	$sp, -64($sp)
+	.cfi_adjust_cfa_offset	64
 	stq	$9, 0($sp)
 	stq	$10, 8($sp)
 	stq	$11, 16($sp)
@@ -395,7 +395,7 @@ entUnaUser:
 	.cfi_rel_offset	$14, 40
 	.cfi_rel_offset	$15, 48
 	lda	$8, 0x3fff
-	addq	$sp, 56, $19
+	addq	$sp, 64, $19
 	bic	$sp, $8, $8
 	jsr	$26, do_entUnaUser
 	ldq	$9, 0($sp)
@@ -405,7 +405,7 @@ entUnaUser:
 	ldq	$13, 32($sp)
 	ldq	$14, 40($sp)
 	ldq	$15, 48($sp)
-	lda	$sp, 56($sp)
+	lda	$sp, 64($sp)
 	.cfi_restore	$9
 	.cfi_restore	$10
 	.cfi_restore	$11
@@ -413,7 +413,7 @@ entUnaUser:
 	.cfi_restore	$13
 	.cfi_restore	$14
 	.cfi_restore	$15
-	.cfi_adjust_cfa_offset	-56
+	.cfi_adjust_cfa_offset	-64
 	br	ret_from_sys_call
 CFI_END_OSF_FRAME entUna
 
diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index a9a38c80c4a7..7004397937cf 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c
@@ -649,7 +649,7 @@ s_reg_to_mem (unsigned long s_reg)
 static int unauser_reg_offsets[32] = {
 	R(r0), R(r1), R(r2), R(r3), R(r4), R(r5), R(r6), R(r7), R(r8),
 	/* r9 ... r15 are stored in front of regs.  */
-	-56, -48, -40, -32, -24, -16, -8,
+	-64, -56, -48, -40, -32, -24, -16,	/* padding at -8 */
 	R(r16), R(r17), R(r18),
 	R(r19), R(r20), R(r21), R(r22), R(r23), R(r24), R(r25), R(r26),
 	R(r27), R(r28), R(gp),
diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index 8c9850437e67..a9816bbc9f34 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -78,8 +78,8 @@ __load_new_mm_context(struct mm_struct *next_mm)
 
 /* Macro for exception fixup code to access integer registers.  */
 #define dpf_reg(r)							\
-	(((unsigned long *)regs)[(r) <= 8 ? (r) : (r) <= 15 ? (r)-16 :	\
-				 (r) <= 18 ? (r)+10 : (r)-10])
+	(((unsigned long *)regs)[(r) <= 8 ? (r) : (r) <= 15 ? (r)-17 :	\
+				 (r) <= 18 ? (r)+11 : (r)-10])
 
 asmlinkage void
 do_page_fault(unsigned long address, unsigned long mmcsr,
-- 
2.51.0