From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> 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: <TASK> __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 </TASK> 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@xxxxxxxxxxxxxxxxxxxxxxxxx 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 <luiz.von.dentz@xxxxxxxxx> --- net/bluetooth/mgmt.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 1f6d083682b8..3ec79c69b0ee 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -1351,7 +1351,13 @@ 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); @@ -1432,6 +1438,11 @@ static void settings_rsp(struct mgmt_pending_cmd *cmd, void *data) { struct cmd_lookup *match = data; + /* dequeue cmd_sync entries using cmd as data as that is about to be + * removed/freed. + */ + hci_cmd_sync_dequeue(match->hdev, NULL, cmd, NULL); + send_settings_rsp(cmd->sk, cmd->opcode, match->hdev); list_del(&cmd->list); -- 2.47.0
