[PATCH] xhci: solve a double free problem while doing s4

[PATCH] xhci: solve a double free problem while doing s4

[Zhangjiantao (Kirin, nanjing)]

when system is doing s4, the process of xhci_resume may be as below:
1、xhci_mem_cleanup
2、xhci_init->xhci_mem_init->xhci_mem_cleanup(when memory is not enough).
xhci_mem_cleanup will be executed twice when system is out of memory.
xhci->port_caps is freed in xhci_mem_cleanup,but it isn't set to NULL.
It will be freed twice when xhci_mem_cleanup is called the second time.

We got following bug when system resumes from s4:

kernel BUG at mm/slub.c:309!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
CPU: 0 PID: 5929 Tainted: G S   W   5.4.96-arm64-desktop #1
pc : __slab_free+0x5c/0x424
lr : kfree+0x30c/0x32c

Call trace:
 __slab_free+0x5c/0x424
 kfree+0x30c/0x32c
 xhci_mem_cleanup+0x394/0x3cc
 xhci_mem_init+0x9ac/0x1070
 xhci_init+0x8c/0x1d0
 xhci_resume+0x1cc/0x5fc
 xhci_plat_resume+0x64/0x70
 platform_pm_thaw+0x28/0x60
 dpm_run_callback+0x54/0x24c
 device_resume+0xd0/0x200
 async_resume+0x24/0x60
 async_run_entry_fn+0x44/0x110
 process_one_work+0x1f0/0x490
 worker_thread+0x5c/0x450
 kthread+0x158/0x160
 ret_from_fork+0x10/0x24

Signed-off-by: Tao Xue <xuetao09@huawei.com>
---
 drivers/usb/host/xhci-mem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index f66815f..e4b0c04 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1924,6 +1924,7 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
 	xhci->hw_ports = NULL;
 	xhci->rh_bw = NULL;
 	xhci->ext_caps = NULL;
+	xhci->port_caps = NULL;
 
 	xhci->page_size = 0;
 	xhci->page_shift = 0;
--
2.7.4

Re: [PATCH] xhci: solve a double free problem while doing s4

[Mathias Nyman]

On 9.6.2021 17.22, Zhangjiantao (Kirin, nanjing) wrote:
> when system is doing s4, the process of xhci_resume may be as below:
> 1、xhci_mem_cleanup
> 2、xhci_init->xhci_mem_init->xhci_mem_cleanup(when memory is not enough).
> xhci_mem_cleanup will be executed twice when system is out of memory.
> xhci->port_caps is freed in xhci_mem_cleanup,but it isn't set to NULL.
> It will be freed twice when xhci_mem_cleanup is called the second time.
> 

Thanks, nice catch

> We got following bug when system resumes from s4:
> 
> kernel BUG at mm/slub.c:309!
> Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
> CPU: 0 PID: 5929 Tainted: G S   W   5.4.96-arm64-desktop #1
> pc : __slab_free+0x5c/0x424
> lr : kfree+0x30c/0x32c
> 
> Call trace:
>  __slab_free+0x5c/0x424
>  kfree+0x30c/0x32c
>  xhci_mem_cleanup+0x394/0x3cc
>  xhci_mem_init+0x9ac/0x1070
>  xhci_init+0x8c/0x1d0
>  xhci_resume+0x1cc/0x5fc
>  xhci_plat_resume+0x64/0x70
>  platform_pm_thaw+0x28/0x60
>  dpm_run_callback+0x54/0x24c
>  device_resume+0xd0/0x200
>  async_resume+0x24/0x60
>  async_run_entry_fn+0x44/0x110
>  process_one_work+0x1f0/0x490
>  worker_thread+0x5c/0x450
>  kthread+0x158/0x160
>  ret_from_fork+0x10/0x24
> 
> Signed-off-by: Tao Xue <xuetao09@huawei.com>

Checkpatch complains:
ERROR: Missing Signed-off-by: line by nominal patch author 'Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>'

Is Zhangjiantao (Kirin, nanjing)  the correct author? If yes can I add 
"Signed-off-by: Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>?

I'll add the stable and correct fixes tags for this.

Thanks
Mathias

Re: [PATCH] xhci: solve a double free problem while doing s4

[gregkh]

On Thu, Jun 10, 2021 at 04:45:54PM +0300, Mathias Nyman wrote:
> On 9.6.2021 17.22, Zhangjiantao (Kirin, nanjing) wrote:
> > when system is doing s4, the process of xhci_resume may be as below:
> > 1、xhci_mem_cleanup
> > 2、xhci_init->xhci_mem_init->xhci_mem_cleanup(when memory is not enough).
> > xhci_mem_cleanup will be executed twice when system is out of memory.
> > xhci->port_caps is freed in xhci_mem_cleanup,but it isn't set to NULL.
> > It will be freed twice when xhci_mem_cleanup is called the second time.
> > 
> 
> Thanks, nice catch
> 
> > We got following bug when system resumes from s4:
> > 
> > kernel BUG at mm/slub.c:309!
> > Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
> > CPU: 0 PID: 5929 Tainted: G S   W   5.4.96-arm64-desktop #1
> > pc : __slab_free+0x5c/0x424
> > lr : kfree+0x30c/0x32c
> > 
> > Call trace:
> >  __slab_free+0x5c/0x424
> >  kfree+0x30c/0x32c
> >  xhci_mem_cleanup+0x394/0x3cc
> >  xhci_mem_init+0x9ac/0x1070
> >  xhci_init+0x8c/0x1d0
> >  xhci_resume+0x1cc/0x5fc
> >  xhci_plat_resume+0x64/0x70
> >  platform_pm_thaw+0x28/0x60
> >  dpm_run_callback+0x54/0x24c
> >  device_resume+0xd0/0x200
> >  async_resume+0x24/0x60
> >  async_run_entry_fn+0x44/0x110
> >  process_one_work+0x1f0/0x490
> >  worker_thread+0x5c/0x450
> >  kthread+0x158/0x160
> >  ret_from_fork+0x10/0x24
> > 
> > Signed-off-by: Tao Xue <xuetao09@huawei.com>
> 
> Checkpatch complains:
> ERROR: Missing Signed-off-by: line by nominal patch author 'Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>'
> 
> Is Zhangjiantao (Kirin, nanjing)  the correct author? If yes can I add 
> "Signed-off-by: Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>?

Please note that it is generally a bad thing for others to add someone
else's s-o-b line, as it is a legal agreement.  It is best for them to
send it instead.

thanks,

greg k-h

Re: [PATCH] xhci: solve a double free problem while doing s4

[Mathias Nyman]

On 10.6.2021 17.01, gregkh@linuxfoundation.org wrote:
> On Thu, Jun 10, 2021 at 04:45:54PM +0300, Mathias Nyman wrote:
>> On 9.6.2021 17.22, Zhangjiantao (Kirin, nanjing) wrote:
>>> when system is doing s4, the process of xhci_resume may be as below:
>>> 1、xhci_mem_cleanup
>>> 2、xhci_init->xhci_mem_init->xhci_mem_cleanup(when memory is not enough).
>>> xhci_mem_cleanup will be executed twice when system is out of memory.
>>> xhci->port_caps is freed in xhci_mem_cleanup,but it isn't set to NULL.
>>> It will be freed twice when xhci_mem_cleanup is called the second time.
>>>
>>
>> Thanks, nice catch
>>
>>> We got following bug when system resumes from s4:
>>>
>>> kernel BUG at mm/slub.c:309!
>>> Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
>>> CPU: 0 PID: 5929 Tainted: G S   W   5.4.96-arm64-desktop #1
>>> pc : __slab_free+0x5c/0x424
>>> lr : kfree+0x30c/0x32c
>>>
>>> Call trace:
>>>  __slab_free+0x5c/0x424
>>>  kfree+0x30c/0x32c
>>>  xhci_mem_cleanup+0x394/0x3cc
>>>  xhci_mem_init+0x9ac/0x1070
>>>  xhci_init+0x8c/0x1d0
>>>  xhci_resume+0x1cc/0x5fc
>>>  xhci_plat_resume+0x64/0x70
>>>  platform_pm_thaw+0x28/0x60
>>>  dpm_run_callback+0x54/0x24c
>>>  device_resume+0xd0/0x200
>>>  async_resume+0x24/0x60
>>>  async_run_entry_fn+0x44/0x110
>>>  process_one_work+0x1f0/0x490
>>>  worker_thread+0x5c/0x450
>>>  kthread+0x158/0x160
>>>  ret_from_fork+0x10/0x24
>>>
>>> Signed-off-by: Tao Xue <xuetao09@huawei.com>
>>
>> Checkpatch complains:
>> ERROR: Missing Signed-off-by: line by nominal patch author 'Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>'
>>
>> Is Zhangjiantao (Kirin, nanjing)  the correct author? If yes can I add 
>> "Signed-off-by: Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>?
> 
> Please note that it is generally a bad thing for others to add someone
> else's s-o-b line, as it is a legal agreement.  It is best for them to
> send it instead.

Good point.
Zhangjiantao (Kirin, nanjing), could you resend with Author/Signed-off-by corrected.

Thanks
-Mathias

Re: [PATCH] xhci: solve a double free problem while doing s4

[Zhangjiantao (Kirin, nanjing)]

On 2021/6/11 3:27, Mathias Nyman wrote:
> On 10.6.2021 17.01, gregkh@linuxfoundation.org wrote:
>> On Thu, Jun 10, 2021 at 04:45:54PM +0300, Mathias Nyman wrote:
>>> On 9.6.2021 17.22, Zhangjiantao (Kirin, nanjing) wrote:
>>>> when system is doing s4, the process of xhci_resume may be as below:
>>>> 1、xhci_mem_cleanup
>>>> 2、xhci_init->xhci_mem_init->xhci_mem_cleanup(when memory is not enough).
>>>> xhci_mem_cleanup will be executed twice when system is out of memory.
>>>> xhci->port_caps is freed in xhci_mem_cleanup,but it isn't set to NULL.
>>>> It will be freed twice when xhci_mem_cleanup is called the second time.
>>>>
>>> Thanks, nice catch
>>>
>>>> We got following bug when system resumes from s4:
>>>>
>>>> kernel BUG at mm/slub.c:309!
>>>> Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
>>>> CPU: 0 PID: 5929 Tainted: G S   W   5.4.96-arm64-desktop #1
>>>> pc : __slab_free+0x5c/0x424
>>>> lr : kfree+0x30c/0x32c
>>>>
>>>> Call trace:
>>>>   __slab_free+0x5c/0x424
>>>>   kfree+0x30c/0x32c
>>>>   xhci_mem_cleanup+0x394/0x3cc
>>>>   xhci_mem_init+0x9ac/0x1070
>>>>   xhci_init+0x8c/0x1d0
>>>>   xhci_resume+0x1cc/0x5fc
>>>>   xhci_plat_resume+0x64/0x70
>>>>   platform_pm_thaw+0x28/0x60
>>>>   dpm_run_callback+0x54/0x24c
>>>>   device_resume+0xd0/0x200
>>>>   async_resume+0x24/0x60
>>>>   async_run_entry_fn+0x44/0x110
>>>>   process_one_work+0x1f0/0x490
>>>>   worker_thread+0x5c/0x450
>>>>   kthread+0x158/0x160
>>>>   ret_from_fork+0x10/0x24
>>>>
>>>> Signed-off-by: Tao Xue <xuetao09@huawei.com>
>>> Checkpatch complains:
>>> ERROR: Missing Signed-off-by: line by nominal patch author 'Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>'
>>>
>>> Is Zhangjiantao (Kirin, nanjing)  the correct author? If yes can I add
>>> "Signed-off-by: Zhangjiantao (Kirin, nanjing) <water.zhangjiantao@huawei.com>?
>> Please note that it is generally a bad thing for others to add someone
>> else's s-o-b line, as it is a legal agreement.  It is best for them to
>> send it instead.
> Good point.
> Zhangjiantao (Kirin, nanjing), could you resend with Author/Signed-off-by corrected.

Yes, I amd  and  Tao Xue are both the correct author, I will resend soon;

Thanks

--Zhangjiantao