Commit 1a32a624 authored Nov 04, 2024 by Luiz Augusto von Dentz Committed by Zhang Changzhong Nov 04, 2024

Bluetooth: L2CAP: Fix uaf in l2cap_connect

mainline inclusion
from mainline-v6.12-rc2
commit 333b4fd11e89b29c84c269123f871883a30be586
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYR99
CVE: CVE-2024-49950

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=333b4fd11e89b29c84c269123f871883a30be586



--------------------------------

[Syzbot reported]
BUG: KASAN: slab-use-after-free in l2cap_connect.constprop.0+0x10d8/0x1270 net/bluetooth/l2cap_core.c:3949
Read of size 8 at addr ffff8880241e9800 by task kworker/u9:0/54

CPU: 0 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.11.0-rc6-syzkaller-00268-g788220eee30d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: hci2 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 l2cap_connect.constprop.0+0x10d8/0x1270 net/bluetooth/l2cap_core.c:3949
 l2cap_connect_req net/bluetooth/l2cap_core.c:4080 [inline]
 l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:4772 [inline]
 l2cap_sig_channel net/bluetooth/l2cap_core.c:5543 [inline]
 l2cap_recv_frame+0xf0b/0x8eb0 net/bluetooth/l2cap_core.c:6825
 l2cap_recv_acldata+0x9b4/0xb70 net/bluetooth/l2cap_core.c:7514
 hci_acldata_packet net/bluetooth/hci_core.c:3791 [inline]
 hci_rx_work+0xaab/0x1610 net/bluetooth/hci_core.c:4028
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
...

Freed by task 5245:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2256 [inline]
 slab_free mm/slub.c:4477 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4598
 l2cap_conn_free net/bluetooth/l2cap_core.c:1810 [inline]
 kref_put include/linux/kref.h:65 [inline]
 l2cap_conn_put net/bluetooth/l2cap_core.c:1822 [inline]
 l2cap_conn_del+0x59d/0x730 net/bluetooth/l2cap_core.c:1802
 l2cap_connect_cfm+0x9e6/0xf80 net/bluetooth/l2cap_core.c:7241
 hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
 hci_conn_failed+0x1c3/0x370 net/bluetooth/hci_conn.c:1265
 hci_abort_conn_sync+0x75a/0xb50 net/bluetooth/hci_sync.c:5583
 abort_conn_sync+0x197/0x360 net/bluetooth/hci_conn.c:2917
 hci_cmd_sync_work+0x1a4/0x410 net/bluetooth/hci_sync.c:328
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Reported-by:  <syzbot+c12e2f941af1feb5632c@syzkaller.appspotmail.com>
Tested-by:  <syzbot+c12e2f941af1feb5632c@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=c12e2f941af1feb5632c


Fixes: 7b064eda ("Bluetooth: Fix authentication if acl data comes before remote feature evt")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Conflicts:
	net/bluetooth/l2cap_core.c
	net/bluetooth/hci_core.c
[eeda1bf97bb5 ("Bluetooth: hci_event: Fix not indicating new connection
for BIG Sync") not merged]
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>

parent 566f4b78

net/bluetooth/hci_core.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -4775,6 +4775,9 @@ static void hci_acldata_packet(struct hci_dev hdev, struct sk_buff skb)

		hci_dev_lock(hdev);
		conn = hci_conn_hash_lookup_handle(hdev, handle);
		if (conn && hci_dev_test_flag(hdev, HCI_MGMT) &&
		!test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &conn->flags))
		mgmt_device_connected(hdev, conn, NULL, 0);
		hci_dev_unlock(hdev);

		if (conn) {

net/bluetooth/hci_event.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -3255,7 +3255,7 @@ static void hci_remote_features_evt(struct hci_dev *hdev,
		goto unlock;
		}

		if (!ev->status && !test_bit(HCI_CONN_MGMT_CONNECTED, &conn->flags)) {
		if (!ev->status) {
		struct hci_cp_remote_name_req cp;
		memset(&cp, 0, sizeof(cp));
		bacpy(&cp.bdaddr, &conn->dst);

net/bluetooth/l2cap_core.c

+0 −9

Original line number	Diff line number	Diff line
		@@ -4272,18 +4272,9 @@ static struct l2cap_chan l2cap_connect(struct l2cap_conn conn,
		static int l2cap_connect_req(struct l2cap_conn *conn,
		struct l2cap_cmd_hdr cmd, u16 cmd_len, u8 data)
		{
		struct hci_dev *hdev = conn->hcon->hdev;
		struct hci_conn *hcon = conn->hcon;

		if (cmd_len < sizeof(struct l2cap_conn_req))
		return -EPROTO;

		hci_dev_lock(hdev);
		if (hci_dev_test_flag(hdev, HCI_MGMT) &&
		!test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
		mgmt_device_connected(hdev, hcon, NULL, 0);
		hci_dev_unlock(hdev);

		l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
		return 0;
		}