From 0b882940665ca2849386ee459d4331aa2f8c4e7d Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Fri, 15 Nov 2024 10:45:31 -0500 Subject: [PATCH 1/3] Bluetooth: MGMT: Fix slab-use-after-free Read in set_powered_sync This fixes the following crash: ================================================================== BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353 Read of size 8 at addr ffff888029b4dd18 by task kworker/u9:0/54 CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.11.0-rc6-syzkaller-01155-gf723224742fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: hci0 hci_cmd_sync_work Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 q kasan_report+0x143/0x180 mm/kasan/report.c:601 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:328 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 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 Allocated by task 5247: 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:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4193 kmalloc_noprof include/linux/slab.h:681 [inline] kzalloc_noprof include/linux/slab.h:807 [inline] mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1394 hci_mgmt_cmd+0xc47/0x11d0 net/bluetooth/hci_sock.c:1712 hci_sock_sendmsg+0x7b8/0x11c0 net/bluetooth/hci_sock.c:1832 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5246: 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:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 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+0x149/0x360 mm/slub.c:4598 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1443 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x112/0x420 net/bluetooth/mgmt.c:9455 hci_dev_close_sync+0x665/0x11a0 net/bluetooth/hci_sync.c:5191 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_dev_close+0x112/0x210 net/bluetooth/hci_core.c:508 sock_do_ioctl+0x158/0x460 net/socket.c:1222 sock_ioctl+0x629/0x8e0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83gv entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com Tested-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf Fixes: 275f3f648702 ("Bluetooth: Fix not checking MGMT cmd pending queue") Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/mgmt.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 1f6d083682b8..e406eb8e4327 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -1318,7 +1318,8 @@ static void mgmt_set_powered_complete(struct hci_dev *hdev, void *data, int err) struct mgmt_mode *cp; /* Make sure cmd still outstanding. */ - if (cmd != pending_find(MGMT_OP_SET_POWERED, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_SET_POWERED, hdev)) return; cp = cmd->param; @@ -1351,7 +1352,13 @@ static void mgmt_set_powered_complete(struct hci_dev *hdev, void *data, int err) static int set_powered_sync(struct hci_dev *hdev, void *data) { struct mgmt_pending_cmd *cmd = data; - struct mgmt_mode *cp = cmd->param; + struct mgmt_mode *cp; + + /* Make sure cmd still outstanding. */ + if (cmd != pending_find(MGMT_OP_SET_POWERED, hdev)) + return -ECANCELED; + + cp = cmd->param; BT_DBG("%s", hdev->name); From a66dfaf18fd61bb75ef8cee83db46b2aadf153d0 Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Thu, 21 Nov 2024 11:09:22 -0500 Subject: [PATCH 2/3] Bluetooth: MGMT: Fix possible deadlocks This fixes possible deadlocks like the following caused by hci_cmd_sync_dequeue causing the destroy function to run: INFO: task kworker/u19:0:143 blocked for more than 120 seconds. Tainted: G W O 6.8.0-2024-03-19-intel-next-iLS-24ww14 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u19:0 state:D stack:0 pid:143 tgid:143 ppid:2 flags:0x00004000 Workqueue: hci0 hci_cmd_sync_work [bluetooth] Call Trace: __schedule+0x374/0xaf0 schedule+0x3c/0xf0 schedule_preempt_disabled+0x1c/0x30 __mutex_lock.constprop.0+0x3ef/0x7a0 __mutex_lock_slowpath+0x13/0x20 mutex_lock+0x3c/0x50 mgmt_set_connectable_complete+0xa4/0x150 [bluetooth] ? kfree+0x211/0x2a0 hci_cmd_sync_dequeue+0xae/0x130 [bluetooth] ? __pfx_cmd_complete_rsp+0x10/0x10 [bluetooth] cmd_complete_rsp+0x26/0x80 [bluetooth] mgmt_pending_foreach+0x4d/0x70 [bluetooth] __mgmt_power_off+0x8d/0x180 [bluetooth] ? _raw_spin_unlock_irq+0x23/0x40 hci_dev_close_sync+0x445/0x5b0 [bluetooth] hci_set_powered_sync+0x149/0x250 [bluetooth] set_powered_sync+0x24/0x60 [bluetooth] hci_cmd_sync_work+0x90/0x150 [bluetooth] process_one_work+0x13e/0x300 worker_thread+0x2f7/0x420 ? __pfx_worker_thread+0x10/0x10 kthread+0x107/0x140 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x3d/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 Tested-by: Kiran K Fixes: f53e1c9c726d ("Bluetooth: MGMT: Fix possible crash on mgmt_index_removed") Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/mgmt.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index e406eb8e4327..b31192d473d0 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -1518,7 +1518,8 @@ static void mgmt_set_discoverable_complete(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "err %d", err); /* Make sure cmd still outstanding. */ - if (cmd != pending_find(MGMT_OP_SET_DISCOVERABLE, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_SET_DISCOVERABLE, hdev)) return; hci_dev_lock(hdev); @@ -1692,7 +1693,8 @@ static void mgmt_set_connectable_complete(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "err %d", err); /* Make sure cmd still outstanding. */ - if (cmd != pending_find(MGMT_OP_SET_CONNECTABLE, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_SET_CONNECTABLE, hdev)) return; hci_dev_lock(hdev); @@ -1924,7 +1926,7 @@ static void set_ssp_complete(struct hci_dev *hdev, void *data, int err) bool changed; /* Make sure cmd still outstanding. */ - if (cmd != pending_find(MGMT_OP_SET_SSP, hdev)) + if (err == -ECANCELED || cmd != pending_find(MGMT_OP_SET_SSP, hdev)) return; if (err) { @@ -3848,7 +3850,8 @@ static void set_name_complete(struct hci_dev *hdev, void *data, int err) bt_dev_dbg(hdev, "err %d", err); - if (cmd != pending_find(MGMT_OP_SET_LOCAL_NAME, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_SET_LOCAL_NAME, hdev)) return; if (status) { @@ -4023,7 +4026,8 @@ static void set_default_phy_complete(struct hci_dev *hdev, void *data, int err) struct sk_buff *skb = cmd->skb; u8 status = mgmt_status(err); - if (cmd != pending_find(MGMT_OP_SET_PHY_CONFIGURATION, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_SET_PHY_CONFIGURATION, hdev)) return; if (!status) { @@ -5914,13 +5918,16 @@ static void start_discovery_complete(struct hci_dev *hdev, void *data, int err) { struct mgmt_pending_cmd *cmd = data; + bt_dev_dbg(hdev, "err %d", err); + + if (err == -ECANCELED) + return; + if (cmd != pending_find(MGMT_OP_START_DISCOVERY, hdev) && cmd != pending_find(MGMT_OP_START_LIMITED_DISCOVERY, hdev) && cmd != pending_find(MGMT_OP_START_SERVICE_DISCOVERY, hdev)) return; - bt_dev_dbg(hdev, "err %d", err); - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode, mgmt_status(err), cmd->param, 1); mgmt_pending_remove(cmd); @@ -6153,7 +6160,8 @@ static void stop_discovery_complete(struct hci_dev *hdev, void *data, int err) { struct mgmt_pending_cmd *cmd = data; - if (cmd != pending_find(MGMT_OP_STOP_DISCOVERY, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_STOP_DISCOVERY, hdev)) return; bt_dev_dbg(hdev, "err %d", err); @@ -8144,7 +8152,8 @@ static void read_local_oob_ext_data_complete(struct hci_dev *hdev, void *data, u8 status = mgmt_status(err); u16 eir_len; - if (cmd != pending_find(MGMT_OP_READ_LOCAL_OOB_EXT_DATA, hdev)) + if (err == -ECANCELED || + cmd != pending_find(MGMT_OP_READ_LOCAL_OOB_EXT_DATA, hdev)) return; if (!status) { From ed9588554943097bdf09588a8a105fbb058869c5 Mon Sep 17 00:00:00 2001 From: Edward Adam Davis Date: Tue, 26 Nov 2024 07:58:43 +0800 Subject: [PATCH 3/3] Bluetooth: SCO: remove the redundant sco_conn_put When adding conn, it is necessary to increase and retain the conn reference count at the same time. Another problem was fixed along the way, conn_put is missing when hcon is NULL in the timeout routine. Fixes: e6720779ae61 ("Bluetooth: SCO: Use kref to track lifetime of sco_conn") Reported-and-tested-by: syzbot+489f78df4709ac2bfdd3@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=489f78df4709ac2bfdd3 Signed-off-by: Edward Adam Davis Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/sco.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index 1b8e468d24cf..78f7bca24487 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -143,6 +143,7 @@ static void sco_sock_timeout(struct work_struct *work) sco_conn_lock(conn); if (!conn->hcon) { sco_conn_unlock(conn); + sco_conn_put(conn); return; } sk = sco_sock_hold(conn); @@ -192,7 +193,6 @@ static struct sco_conn *sco_conn_add(struct hci_conn *hcon) conn->hcon = hcon; sco_conn_unlock(conn); } - sco_conn_put(conn); return conn; }