Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1388163 > unrolled thread

Re: [PATCH] usb: hub: fix panic caused by NULL bos pointer during reset device

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  Re: [PATCH] usb: hub: fix panic caused by NULL bos pointer during  reset device Greg KH <gregkh@linuxfoundation.org> - 2016-04-27 00:20 +0200
    RE: [PATCH] usb: hub: fix panic caused by NULL bos pointer during  reset device "Du, Changbin" <changbin.du@intel.com> - 2016-04-27 05:00 +0200
      Re: [PATCH] usb: hub: fix panic caused by NULL bos pointer during  reset device Tony Battersby <tonyb@cybernetics.com> - 2016-04-27 15:50 +0200

#1388163 — Re: [PATCH] usb: hub: fix panic caused by NULL bos pointer during reset device

On Tue, Mar 08, 2016 at 05:15:17PM +0800, changbin.du@intel.com wrote:
> From: "Du, Changbin" <changbin.du@intel.com>
> 
> This is a reworked patch based on reverted commit d8f00cd685f5 ("usb:
> hub: do not clear BOS field during reset device").
> 
> The privious one caused double mem-free if run to re_enumerate label.
> New patch title changed to distinguish from old one. And I have tested
> it with memory debugging options.
> 
> In function usb_reset_and_verify_device, the old BOS descriptor may
> still be used before allocating a new one. (usb_disable_lpm function
> uses it under the situation that it fails at usb_disable_link_state.)
> So we cannot set the udev->bos to NULL before that, just keep what it
> was. It will be overwrite when allocating a new one.
> 
> How to reproduce:
> 1. connect one usb3 hub to xhci port.
> 2. connect several lpm-capable super-speed usb disk to the hub.
> 3. copy big files to the usb disks.
> 4. disconnect the hub and repeat step 1-4.
> 
> Crash log:
> BUG: unable to handle kernel NULL pointer dereference at
> 0000000000000010
> IP: [<ffffffff8171f98d>] usb_enable_link_state+0x2d/0x2f0
> Call Trace:
> [<ffffffff8171ed5b>] ? usb_set_lpm_timeout+0x12b/0x140
> [<ffffffff8171fcd1>] usb_enable_lpm+0x81/0xa0
> [<ffffffff8171fdd8>] usb_disable_lpm+0xa8/0xc0
> [<ffffffff8171fe1c>] usb_unlocked_disable_lpm+0x2c/0x50
> [<ffffffff81723933>] usb_reset_and_verify_device+0xc3/0x710
> [<ffffffff8172c4ed>] ? usb_sg_wait+0x13d/0x190
> [<ffffffff81724743>] usb_reset_device+0x133/0x280
> [<ffffffff8179ccd1>] usb_stor_port_reset+0x61/0x70
> [<ffffffff8179cd68>] usb_stor_invoke_transport+0x88/0x520
> 
> Signed-off-by: Du, Changbin <changbin.du@intel.com>
> ---
>  drivers/usb/core/hub.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)

Is this patch still needed?  I thought we had some other fix in this
area...

confused,

greg k-h


> 
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 51b43691..27444e5 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -5401,7 +5401,6 @@ static int usb_reset_and_verify_device(struct usb_device *udev)
>  	}
>  
>  	bos = udev->bos;
> -	udev->bos = NULL;
>  
>  	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
>  
> @@ -5494,13 +5493,18 @@ done:
>  	usb_set_usb2_hardware_lpm(udev, 1);
>  	usb_unlocked_enable_lpm(udev);
>  	usb_enable_ltm(udev);
> -	usb_release_bos_descriptor(udev);
> -	udev->bos = bos;
> +	/* release the new BOS descriptor allocated by hub_port_init() */
> +	if (udev->bos != bos) {
> +		usb_release_bos_descriptor(udev);
> +		udev->bos = bos;
> +	}
>  	return 0;
>  
>  re_enumerate:
> -	usb_release_bos_descriptor(udev);
> -	udev->bos = bos;
> +	if (udev->bos != bos) {
> +		usb_release_bos_descriptor(udev);
> +		udev->bos = bos;
> +	}
>  re_enumerate_no_bos:
>  	/* LPM state doesn't matter when we're about to destroy the device. */
>  	hub_port_logical_disconnect(parent_hub, port1);
> -- 
> 2.5.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

[toc] | [next] | [standalone]

#1388613

> On Tue, Mar 08, 2016 at 05:15:17PM +0800, changbin.du@intel.com wrote:
> > From: "Du, Changbin" <changbin.du@intel.com>
> >
> > This is a reworked patch based on reverted commit d8f00cd685f5 ("usb:
> > hub: do not clear BOS field during reset device").
> >
> > The privious one caused double mem-free if run to re_enumerate label.
> > New patch title changed to distinguish from old one. And I have tested
> > it with memory debugging options.
> >
> > In function usb_reset_and_verify_device, the old BOS descriptor may
> > still be used before allocating a new one. (usb_disable_lpm function
> > uses it under the situation that it fails at usb_disable_link_state.)
> > So we cannot set the udev->bos to NULL before that, just keep what it
> > was. It will be overwrite when allocating a new one.
> >
> > How to reproduce:
> > 1. connect one usb3 hub to xhci port.
> > 2. connect several lpm-capable super-speed usb disk to the hub.
> > 3. copy big files to the usb disks.
> > 4. disconnect the hub and repeat step 1-4.
> >
> > Crash log:
> > BUG: unable to handle kernel NULL pointer dereference at
> > 0000000000000010
> > IP: [<ffffffff8171f98d>] usb_enable_link_state+0x2d/0x2f0
> > Call Trace:
> > [<ffffffff8171ed5b>] ? usb_set_lpm_timeout+0x12b/0x140
> > [<ffffffff8171fcd1>] usb_enable_lpm+0x81/0xa0
> > [<ffffffff8171fdd8>] usb_disable_lpm+0xa8/0xc0
> > [<ffffffff8171fe1c>] usb_unlocked_disable_lpm+0x2c/0x50
> > [<ffffffff81723933>] usb_reset_and_verify_device+0xc3/0x710
> > [<ffffffff8172c4ed>] ? usb_sg_wait+0x13d/0x190
> > [<ffffffff81724743>] usb_reset_device+0x133/0x280
> > [<ffffffff8179ccd1>] usb_stor_port_reset+0x61/0x70
> > [<ffffffff8179cd68>] usb_stor_invoke_transport+0x88/0x520
> >
> > Signed-off-by: Du, Changbin <changbin.du@intel.com>
> > ---
> >  drivers/usb/core/hub.c | 14 +++++++++-----
> >  1 file changed, 9 insertions(+), 5 deletions(-)
> 
> Is this patch still needed?  I thought we had some other fix in this
> area...
> 
> confused,
> 
> greg k-h
> 

Hi, Greg k-h,
Sorry for it confused you. This patch still need. This is same fix with
previous commit d8f00cd685f5 ("usb: hub: do not clear BOS field
during reset device"). But d8f00cd685f5 is buggy and reverted. This
new patch should be the final fix.

Best Regards,
Du, Changbin

[toc] | [prev] | [next] | [standalone]

#1389060

On 04/26/2016 10:53 PM, Du, Changbin wrote:
>> On Tue, Mar 08, 2016 at 05:15:17PM +0800, changbin.du@intel.com wrote:
>>> From: "Du, Changbin" <changbin.du@intel.com>
>>>
>>> This is a reworked patch based on reverted commit d8f00cd685f5 ("usb:
>>> hub: do not clear BOS field during reset device").
>>>
>>> The privious one caused double mem-free if run to re_enumerate label.
>>> New patch title changed to distinguish from old one. And I have tested
>>> it with memory debugging options.
>>>
>>> In function usb_reset_and_verify_device, the old BOS descriptor may
>>> still be used before allocating a new one. (usb_disable_lpm function
>>> uses it under the situation that it fails at usb_disable_link_state.)
>>> So we cannot set the udev->bos to NULL before that, just keep what it
>>> was. It will be overwrite when allocating a new one.
>>>
>>> How to reproduce:
>>> 1. connect one usb3 hub to xhci port.
>>> 2. connect several lpm-capable super-speed usb disk to the hub.
>>> 3. copy big files to the usb disks.
>>> 4. disconnect the hub and repeat step 1-4.
>>>
>>> Crash log:
>>> BUG: unable to handle kernel NULL pointer dereference at
>>> 0000000000000010
>>> IP: [<ffffffff8171f98d>] usb_enable_link_state+0x2d/0x2f0
>>> Call Trace:
>>> [<ffffffff8171ed5b>] ? usb_set_lpm_timeout+0x12b/0x140
>>> [<ffffffff8171fcd1>] usb_enable_lpm+0x81/0xa0
>>> [<ffffffff8171fdd8>] usb_disable_lpm+0xa8/0xc0
>>> [<ffffffff8171fe1c>] usb_unlocked_disable_lpm+0x2c/0x50
>>> [<ffffffff81723933>] usb_reset_and_verify_device+0xc3/0x710
>>> [<ffffffff8172c4ed>] ? usb_sg_wait+0x13d/0x190
>>> [<ffffffff81724743>] usb_reset_device+0x133/0x280
>>> [<ffffffff8179ccd1>] usb_stor_port_reset+0x61/0x70
>>> [<ffffffff8179cd68>] usb_stor_invoke_transport+0x88/0x520
>>>
>>> Signed-off-by: Du, Changbin <changbin.du@intel.com>
>>> ---
>>>  drivers/usb/core/hub.c | 14 +++++++++-----
>>>  1 file changed, 9 insertions(+), 5 deletions(-)
>> Is this patch still needed?  I thought we had some other fix in this
>> area...
>>
>> confused,
>>
>> greg k-h
>>
> Hi, Greg k-h,
> Sorry for it confused you. This patch still need. This is same fix with
> previous commit d8f00cd685f5 ("usb: hub: do not clear BOS field
> during reset device"). But d8f00cd685f5 is buggy and reverted. This
> new patch should be the final fix.
>
> Best Regards,
> Du, Changbin
>

I think Greg is referring to commit 464ad8c43a9e ("usb: core : hub: Fix
BOS 'NULL pointer' kernel panic"), which has already been applied
upstream.  It looks to me like that patch might have fixed the same
problem in a different way, in which case Changbin's patch is not
needed.  But I haven't been involved in developing or testing that
patch, so I can't say for sure.  At the very least, 464ad8c43a9e
conflicts with Changbin's patch.

Changbin, can you take a look at 464ad8c43a9e and see if that fixes the
same problem that your patch did?

Thanks,
Tony Battersby

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web