Re: WARNING: ODEBUG bug in rsi_probe

From: Andrey Konovalov
Date: Thu Nov 28 2019 - 13:12:40 EST

On Thu, Nov 28, 2019 at 7:00 PM Johan Hovold <johan@xxxxxxxxxx> wrote:
>
> On Fri, Apr 19, 2019 at 04:54:06PM -0700, syzbot wrote:
> > syzbot has found a reproducer for the following crash on:
> >
> > HEAD commit: d34f9519 usb-fuzzer: main usb gadget fuzzer driver
> > git tree: https://github.com/google/kasan/tree/usb-fuzzer
> > console output: https://syzkaller.appspot.com/x/log.txt?x=13431e7b200000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=c73d1bb5aeaeae20
> > dashboard link: https://syzkaller.appspot.com/bug?extid=1d1597a5aa3679c65b9f
> > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12534fdd200000
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=147c9247200000
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: syzbot+1d1597a5aa3679c65b9f@xxxxxxxxxxxxxxxxxxxxxxxxx
> >
> > rsi_91x: rsi_load_firmware: REGOUT read failed
> > rsi_91x: rsi_hal_device_init: Failed to load TA instructions
> > rsi_91x: rsi_probe: Failed in device init
> > ------------[ cut here ]------------
> > ODEBUG: free active (active state 0) object type: timer_list hint:
> > bl_cmd_timeout+0x0/0x50 drivers/net/wireless/rsi/rsi_91x_hal.c:577
> > WARNING: CPU: 0 PID: 563 at lib/debugobjects.c:325
> > debug_print_object+0x162/0x250 lib/debugobjects.c:325
> > Kernel panic - not syncing: panic_on_warn set ...
> > CPU: 0 PID: 563 Comm: kworker/0:2 Not tainted 5.1.0-rc5-319617-gd34f951 #4
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> > Google 01/01/2011
> > Workqueue: usb_hub_wq hub_event
> > Call Trace:
> > __dump_stack lib/dump_stack.c:77 [inline]
> > dump_stack+0xe8/0x16e lib/dump_stack.c:113
> > panic+0x29d/0x5f2 kernel/panic.c:214
> > __warn.cold+0x20/0x48 kernel/panic.c:571
> > report_bug+0x262/0x2a0 lib/bug.c:186
> > fixup_bug arch/x86/kernel/traps.c:179 [inline]
> > fixup_bug arch/x86/kernel/traps.c:174 [inline]
> > do_error_trap+0x130/0x1f0 arch/x86/kernel/traps.c:272
> > do_invalid_op+0x37/0x40 arch/x86/kernel/traps.c:291
> > invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
> > RIP: 0010:debug_print_object+0x162/0x250 lib/debugobjects.c:325
> > Code: dd c0 a8 b3 8e 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 bf 00 00 00 48
> > 8b 14 dd c0 a8 b3 8e 48 c7 c7 40 9d b3 8e e8 8e c3 d2 fd <0f> 0b 83 05 f9
> > 0f 5a 10 01 48 83 c4 20 5b 5d 41 5c 41 5d c3 48 89
> > RSP: 0018:ffff88809e1ef110 EFLAGS: 00010086
> > RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
> > RDX: 0000000000000000 RSI: ffffffff815b1d22 RDI: ffffed1013c3de14
> > RBP: 0000000000000001 R08: ffff88809e1cb100 R09: ffffed1015a03edb
> > R10: ffffed1015a03eda R11: ffff8880ad01f6d7 R12: ffffffff917e77c0
> > R13: ffffffff8161e740 R14: ffffffff96d3ea28 R15: ffff8880a5a75f60
> > __debug_check_no_obj_freed lib/debugobjects.c:785 [inline]
> > debug_check_no_obj_freed+0x2a3/0x42e lib/debugobjects.c:817
> > slab_free_hook mm/slub.c:1426 [inline]
> > slab_free_freelist_hook+0xfb/0x140 mm/slub.c:1456
> > slab_free mm/slub.c:3003 [inline]
> > kfree+0xce/0x280 mm/slub.c:3958
> > rsi_probe+0xdf3/0x140d drivers/net/wireless/rsi/rsi_91x_sdio.c:1178
> > usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
> > really_probe+0x2da/0xb10 drivers/base/dd.c:509
> > driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
> > __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
> > bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
> > __device_attach+0x223/0x3a0 drivers/base/dd.c:844
> > bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
> > device_add+0xad2/0x16e0 drivers/base/core.c:2106
> > usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021
> > generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
> > usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
> > really_probe+0x2da/0xb10 drivers/base/dd.c:509
> > driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
> > __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
> > bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
> > __device_attach+0x223/0x3a0 drivers/base/dd.c:844
> > bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
> > device_add+0xad2/0x16e0 drivers/base/core.c:2106
> > usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534
> > hub_port_connect drivers/usb/core/hub.c:5089 [inline]
> > hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
> > port_event drivers/usb/core/hub.c:5350 [inline]
> > hub_event+0x1398/0x3b00 drivers/usb/core/hub.c:5432
> > process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
> > worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
> > kthread+0x313/0x420 kernel/kthread.c:253
> > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
> >
> > ======================================================
>
> Let's try to test the below combined patch which fixes both the above
> use-after-free issue and a second one which syzbot is likely to hit once
> the first one is fixed. Now hopefully with a proper commit id:
>
> #syz test: https://github.com/google/kasan.git da06441bb4

Hi Johan,

The reproducer was found on commit d34f9519, so you need to specify
that commit exactly when testing patches. Otherwise the reported
result might be incorrect.

Thanks!

>
> Johan
>
>
> From 0fff9e8be7d92c37c0a03b8f58db415eb042c325 Mon Sep 17 00:00:00 2001
> From: Johan Hovold <johan@xxxxxxxxxx>
> Date: Thu, 28 Nov 2019 16:07:57 +0100
> Subject: [PATCH] rsi: fix use-after-free on failed probe and unbind
>
> Make sure to stop both URBs before returning after failed probe as well
> as on disconnect to avoid use-after-free in the completion handler.
>
> Reported-by: syzbot+b563b7f8dbe8223a51e8@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: a4302bff28e2 ("rsi: add bluetooth rx endpoint")
> Fixes: dad0d04fa7ba ("rsi: Add RS9113 wireless driver")
> Cc: stable <stable@xxxxxxxxxxxxxxx> # 3.15
> Cc: Siva Rebbagondla <siva.rebbagondla@xxxxxxxxxxxxxxxxxx>
> Cc: Prameela Rani Garnepudi <prameela.j04cs@xxxxxxxxx>
> Cc: Amitkumar Karwar <amit.karwar@xxxxxxxxxxxxxxxxxx>
> Cc: Fariya Fatima <fariyaf@xxxxxxxxx>
>
> rsi: fix use-after-free on probe errors
>
> The driver would fail to stop the command timer in most error paths,
> something which specifically could lead to the timer being freed while
> still active on I/O errors during probe.
>
> Fix this by making sure that each function starting the timer also stops
> it in all relevant error paths.
>
> Reported-by: syzbot+1d1597a5aa3679c65b9f@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: b78e91bcfb33 ("rsi: Add new firmware loading method")
> Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.12
> Cc: Prameela Rani Garnepudi <prameela.j04cs@xxxxxxxxx>
> Cc: Amitkumar Karwar <amit.karwar@xxxxxxxxxxxxxxxxxx>
> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
> ---
> drivers/net/wireless/rsi/rsi_91x_hal.c | 12 ++++++------
> drivers/net/wireless/rsi/rsi_91x_usb.c | 18 +++++++++++++++++-
> 2 files changed, 23 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/wireless/rsi/rsi_91x_hal.c b/drivers/net/wireless/rsi/rsi_91x_hal.c
> index f84250bdb8cf..6f8d5f9a9f7e 100644
> --- a/drivers/net/wireless/rsi/rsi_91x_hal.c
> +++ b/drivers/net/wireless/rsi/rsi_91x_hal.c
> @@ -622,6 +622,7 @@ static int bl_cmd(struct rsi_hw *adapter, u8 cmd, u8 exp_resp, char *str)
> bl_start_cmd_timer(adapter, timeout);
> status = bl_write_cmd(adapter, cmd, exp_resp, &regout_val);
> if (status < 0) {
> + bl_stop_cmd_timer(adapter);
> rsi_dbg(ERR_ZONE,
> "%s: Command %s (%0x) writing failed..\n",
> __func__, str, cmd);
> @@ -737,10 +738,9 @@ static int ping_pong_write(struct rsi_hw *adapter, u8 cmd, u8 *addr, u32 size)
> }
>
> status = bl_cmd(adapter, cmd_req, cmd_resp, str);
> - if (status) {
> - bl_stop_cmd_timer(adapter);
> + if (status)
> return status;
> - }
> +
> return 0;
> }
>
> @@ -828,10 +828,9 @@ static int auto_fw_upgrade(struct rsi_hw *adapter, u8 *flash_content,
>
> status = bl_cmd(adapter, EOF_REACHED, FW_LOADING_SUCCESSFUL,
> "EOF_REACHED");
> - if (status) {
> - bl_stop_cmd_timer(adapter);
> + if (status)
> return status;
> - }
> +
> rsi_dbg(INFO_ZONE, "FW loading is done and FW is running..\n");
> return 0;
> }
> @@ -849,6 +848,7 @@ static int rsi_hal_prepare_fwload(struct rsi_hw *adapter)
> &regout_val,
> RSI_COMMON_REG_SIZE);
> if (status < 0) {
> + bl_stop_cmd_timer(adapter);
> rsi_dbg(ERR_ZONE,
> "%s: REGOUT read failed\n", __func__);
> return status;
> diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c
> index 53f41fc2cadf..30bed719486e 100644
> --- a/drivers/net/wireless/rsi/rsi_91x_usb.c
> +++ b/drivers/net/wireless/rsi/rsi_91x_usb.c
> @@ -292,6 +292,15 @@ static void rsi_rx_done_handler(struct urb *urb)
> dev_kfree_skb(rx_cb->rx_skb);
> }
>
> +static void rsi_rx_urb_kill(struct rsi_hw *adapter, u8 ep_num)
> +{
> + struct rsi_91x_usbdev *dev = (struct rsi_91x_usbdev *)adapter->rsi_dev;
> + struct rx_usb_ctrl_block *rx_cb = &dev->rx_cb[ep_num - 1];
> + struct urb *urb = rx_cb->rx_urb;
> +
> + usb_kill_urb(urb);
> +}
> +
> /**
> * rsi_rx_urb_submit() - This function submits the given URB to the USB stack.
> * @adapter: Pointer to the adapter structure.
> @@ -823,10 +832,13 @@ static int rsi_probe(struct usb_interface *pfunction,
> if (adapter->priv->coex_mode > 1) {
> status = rsi_rx_urb_submit(adapter, BT_EP);
> if (status)
> - goto err1;
> + goto err_kill_wlan_urb;
> }
>
> return 0;
> +
> +err_kill_wlan_urb:
> + rsi_rx_urb_kill(adapter, WLAN_EP);
> err1:
> rsi_deinit_usb_interface(adapter);
> err:
> @@ -857,6 +869,10 @@ static void rsi_disconnect(struct usb_interface *pfunction)
> adapter->priv->bt_adapter = NULL;
> }
>
> + if (adapter->priv->coex_mode > 1)
> + rsi_rx_urb_kill(adapter, BT_EP);
> + rsi_rx_urb_kill(adapter, WLAN_EP);
> +
> rsi_reset_card(adapter);
> rsi_deinit_usb_interface(adapter);
> rsi_91x_deinit(adapter);
> --
> 2.24.0
>