All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] drivers: nfc: nfcmrvl: reorder destructive operations in nfcmrvl_nci_unregister_dev to avoid bugs
@ 2022-04-25  3:10 Duoming Zhou
  2022-04-25  7:59 ` Krzysztof Kozlowski
  0 siblings, 1 reply; 3+ messages in thread
From: Duoming Zhou @ 2022-04-25  3:10 UTC (permalink / raw)
  To: krzysztof.kozlowski, linux-kernel
  Cc: netdev, broonie, akpm, alexander.deucher, gregkh, davem, linma,
	Duoming Zhou

There are destructive operations such as nfcmrvl_fw_dnld_abort and
gpio_free in nfcmrvl_nci_unregister_dev. The resources such as firmware,
gpio and so on could be destructed while the upper layer functions such as
nfcmrvl_fw_dnld_start and nfcmrvl_nci_recv_frame is executing, which leads
to double-free, use-after-free and null-ptr-deref bugs.

There are three situations that could lead to double-free bugs.

The first situation is shown below:

   (Thread 1)                 |      (Thread 2)
nfcmrvl_fw_dnld_start         |
 ...                          |  nfcmrvl_nci_unregister_dev
 release_firmware()           |   nfcmrvl_fw_dnld_abort
  kfree(fw) //(1)             |    fw_dnld_over
                              |     release_firmware
  ...                         |      kfree(fw) //(2)
                              |     ...

The second situation is shown below:

   (Thread 1)                 |      (Thread 2)
nfcmrvl_fw_dnld_start         |
 ...                          |
 mod_timer                    |
 (wait a time)                |
 fw_dnld_timeout              |  nfcmrvl_nci_unregister_dev
   fw_dnld_over               |   nfcmrvl_fw_dnld_abort
    release_firmware          |    fw_dnld_over
     kfree(fw) //(1)          |     release_firmware
     ...                      |      kfree(fw) //(2)

The third situation is shown below:

       (Thread 1)               |       (Thread 2)
nfcmrvl_nci_recv_frame          |
 if(..->fw_download_in_progress)|
  nfcmrvl_fw_dnld_recv_frame    |
   queue_work                   |
                                |
fw_dnld_rx_work                 | nfcmrvl_nci_unregister_dev
 fw_dnld_over                   |  nfcmrvl_fw_dnld_abort
  release_firmware              |   fw_dnld_over
   kfree(fw) //(1)              |    release_firmware
                                |     kfree(fw) //(2)

The firmware struct is deallocated in position (1) and deallocated
in position (2) again.

The crash trace triggered by POC is like below:

[  122.640457] BUG: KASAN: double-free or invalid-free in fw_dnld_over+0x28/0xf0
[  122.640457] Call Trace:
[  122.640457]  <TASK>
[  122.640457]  kfree+0xb0/0x330
[  122.640457]  fw_dnld_over+0x28/0xf0
[  122.640457]  nfcmrvl_nci_unregister_dev+0x61/0x70
[  122.640457]  nci_uart_tty_close+0x87/0xd0
[  122.640457]  tty_ldisc_kill+0x3e/0x80
[  122.640457]  tty_ldisc_hangup+0x1b2/0x2c0
[  122.640457]  __tty_hangup.part.0+0x316/0x520
[  122.640457]  tty_release+0x200/0x670
[  122.640457]  __fput+0x110/0x410
[  122.640457]  task_work_run+0x86/0xd0
[  122.640457]  exit_to_user_mode_prepare+0x1aa/0x1b0
[  122.640457]  syscall_exit_to_user_mode+0x19/0x50
[  122.640457]  do_syscall_64+0x48/0x90
[  122.640457]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  122.640457] RIP: 0033:0x7f68433f6beb

What's more, there are also use-after-free and null-ptr-deref bugs
in nfcmrvl_fw_dnld_start. If we deallocate firmware struct, gpio or
set null to the members of priv->fw_dnld in nfcmrvl_nci_unregister_dev,
then, we dereference firmware, gpio or the members of priv->fw_dnld in
nfcmrvl_fw_dnld_start, the UAF or NPD bugs will happen.

This patch reorders destructive operations after nci_unregister_device
to avoid the double-free, UAF and NPD bugs, as nci_unregister_device
is well synchronized and won't return if there is a running routine.
This was mentioned in commit 3e3b5dfcd16a ("NFC: reorder the logic in
nfc_{un,}register_device").

Fixes: 3194c6870158 ("NFC: nfcmrvl: add firmware download support")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Lin Ma <linma@zju.edu.cn>
---
 drivers/nfc/nfcmrvl/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nfc/nfcmrvl/main.c b/drivers/nfc/nfcmrvl/main.c
index 2fcf545012b..1a5284de434 100644
--- a/drivers/nfc/nfcmrvl/main.c
+++ b/drivers/nfc/nfcmrvl/main.c
@@ -183,6 +183,7 @@ void nfcmrvl_nci_unregister_dev(struct nfcmrvl_private *priv)
 {
 	struct nci_dev *ndev = priv->ndev;
 
+	nci_unregister_device(ndev);
 	if (priv->ndev->nfc_dev->fw_download_in_progress)
 		nfcmrvl_fw_dnld_abort(priv);
 
@@ -191,7 +192,6 @@ void nfcmrvl_nci_unregister_dev(struct nfcmrvl_private *priv)
 	if (gpio_is_valid(priv->config.reset_n_io))
 		gpio_free(priv->config.reset_n_io);
 
-	nci_unregister_device(ndev);
 	nci_free_device(ndev);
 	kfree(priv);
 }
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] drivers: nfc: nfcmrvl: reorder destructive operations in nfcmrvl_nci_unregister_dev to avoid bugs
  2022-04-25  3:10 [PATCH] drivers: nfc: nfcmrvl: reorder destructive operations in nfcmrvl_nci_unregister_dev to avoid bugs Duoming Zhou
@ 2022-04-25  7:59 ` Krzysztof Kozlowski
  2022-04-25  9:09   ` duoming
  0 siblings, 1 reply; 3+ messages in thread
From: Krzysztof Kozlowski @ 2022-04-25  7:59 UTC (permalink / raw)
  To: Duoming Zhou, linux-kernel
  Cc: netdev, broonie, akpm, alexander.deucher, gregkh, davem, linma

On 25/04/2022 05:10, Duoming Zhou wrote:
> There are destructive operations such as nfcmrvl_fw_dnld_abort and
> gpio_free in nfcmrvl_nci_unregister_dev. The resources such as firmware,
> gpio and so on could be destructed while the upper layer functions such as
> nfcmrvl_fw_dnld_start and nfcmrvl_nci_recv_frame is executing, which leads
> to double-free, use-after-free and null-ptr-deref bugs.

You need to correct the subject prefix because it does not describe the
subsystem (git log oneline --).

> 
> There are three situations that could lead to double-free bugs.
> 
> The first situation is shown below:
> 
>    (Thread 1)                 |      (Thread 2)
> nfcmrvl_fw_dnld_start         |
>  ...                          |  nfcmrvl_nci_unregister_dev
>  release_firmware()           |   nfcmrvl_fw_dnld_abort
>   kfree(fw) //(1)             |    fw_dnld_over
>                               |     release_firmware
>   ...                         |      kfree(fw) //(2)
>                               |     ...
> 
> The second situation is shown below:
> 
>    (Thread 1)                 |      (Thread 2)
> nfcmrvl_fw_dnld_start         |
>  ...                          |
>  mod_timer                    |
>  (wait a time)                |
>  fw_dnld_timeout              |  nfcmrvl_nci_unregister_dev
>    fw_dnld_over               |   nfcmrvl_fw_dnld_abort
>     release_firmware          |    fw_dnld_over
>      kfree(fw) //(1)          |     release_firmware
>      ...                      |      kfree(fw) //(2)
> 
> The third situation is shown below:
> 
>        (Thread 1)               |       (Thread 2)
> nfcmrvl_nci_recv_frame          |
>  if(..->fw_download_in_progress)|
>   nfcmrvl_fw_dnld_recv_frame    |
>    queue_work                   |
>                                 |
> fw_dnld_rx_work                 | nfcmrvl_nci_unregister_dev
>  fw_dnld_over                   |  nfcmrvl_fw_dnld_abort
>   release_firmware              |   fw_dnld_over
>    kfree(fw) //(1)              |    release_firmware
>                                 |     kfree(fw) //(2)
> 
> The firmware struct is deallocated in position (1) and deallocated
> in position (2) again.
> 
> The crash trace triggered by POC is like below:
> 
> [  122.640457] BUG: KASAN: double-free or invalid-free in fw_dnld_over+0x28/0xf0
> [  122.640457] Call Trace:
> [  122.640457]  <TASK>
> [  122.640457]  kfree+0xb0/0x330
> [  122.640457]  fw_dnld_over+0x28/0xf0
> [  122.640457]  nfcmrvl_nci_unregister_dev+0x61/0x70
> [  122.640457]  nci_uart_tty_close+0x87/0xd0
> [  122.640457]  tty_ldisc_kill+0x3e/0x80
> [  122.640457]  tty_ldisc_hangup+0x1b2/0x2c0
> [  122.640457]  __tty_hangup.part.0+0x316/0x520
> [  122.640457]  tty_release+0x200/0x670
> [  122.640457]  __fput+0x110/0x410
> [  122.640457]  task_work_run+0x86/0xd0
> [  122.640457]  exit_to_user_mode_prepare+0x1aa/0x1b0
> [  122.640457]  syscall_exit_to_user_mode+0x19/0x50
> [  122.640457]  do_syscall_64+0x48/0x90
> [  122.640457]  entry_SYSCALL_64_after_hwframe+0x44/0xae
> [  122.640457] RIP: 0033:0x7f68433f6beb
> 
> What's more, there are also use-after-free and null-ptr-deref bugs
> in nfcmrvl_fw_dnld_start. If we deallocate firmware struct, gpio or
> set null to the members of priv->fw_dnld in nfcmrvl_nci_unregister_dev,
> then, we dereference firmware, gpio or the members of priv->fw_dnld in
> nfcmrvl_fw_dnld_start, the UAF or NPD bugs will happen.
> 
> This patch reorders destructive operations after nci_unregister_device
> to avoid the double-free, UAF and NPD bugs, as nci_unregister_device
> is well synchronized and won't return if there is a running routine.
> This was mentioned in commit 3e3b5dfcd16a ("NFC: reorder the logic in
> nfc_{un,}register_device").
> 
> Fixes: 3194c6870158 ("NFC: nfcmrvl: add firmware download support")
> Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
> Reviewed-by: Lin Ma <linma@zju.edu.cn>

It's the first submission, how this review appeared?

On the other hand, you already sent something similar, so is it a v2? I
am sorry but this is very confusing. Looks like
https://lore.kernel.org/all/20220425005718.33639-1-duoming@zju.edu.cn/
but there is no changelog and commit description is different.

Please read:
https://elixir.bootlin.com/linux/v5.18-rc4/source/Documentation/process/submitting-patches.rst


> ---
>  drivers/nfc/nfcmrvl/main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 


Best regards,
Krzysztof

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: Re: [PATCH] drivers: nfc: nfcmrvl: reorder destructive operations in nfcmrvl_nci_unregister_dev to avoid bugs
  2022-04-25  7:59 ` Krzysztof Kozlowski
@ 2022-04-25  9:09   ` duoming
  0 siblings, 0 replies; 3+ messages in thread
From: duoming @ 2022-04-25  9:09 UTC (permalink / raw)
  To: Krzysztof Kozlowski
  Cc: linux-kernel, netdev, broonie, akpm, alexander.deucher, gregkh,
	davem, linma

Hello,

On Mon, 25 Apr 2022 09:59:32 +0200 Krzysztof wrote:

> > There are destructive operations such as nfcmrvl_fw_dnld_abort and
> > gpio_free in nfcmrvl_nci_unregister_dev. The resources such as firmware,
> > gpio and so on could be destructed while the upper layer functions such as
> > nfcmrvl_fw_dnld_start and nfcmrvl_nci_recv_frame is executing, which leads
> > to double-free, use-after-free and null-ptr-deref bugs.
> 
> You need to correct the subject prefix because it does not describe the
> subsystem (git log oneline --).

I will change the subject prefix to "nfc: nfcmrvl: uart: ".

> > 
> > There are three situations that could lead to double-free bugs.
> > 
> > The first situation is shown below:
> > 
> >    (Thread 1)                 |      (Thread 2)
> > nfcmrvl_fw_dnld_start         |
> >  ...                          |  nfcmrvl_nci_unregister_dev
> >  release_firmware()           |   nfcmrvl_fw_dnld_abort
> >   kfree(fw) //(1)             |    fw_dnld_over
> >                               |     release_firmware
> >   ...                         |      kfree(fw) //(2)
> >                               |     ...
> > 
> > The second situation is shown below:
> > 
> >    (Thread 1)                 |      (Thread 2)
> > nfcmrvl_fw_dnld_start         |
> >  ...                          |
> >  mod_timer                    |
> >  (wait a time)                |
> >  fw_dnld_timeout              |  nfcmrvl_nci_unregister_dev
> >    fw_dnld_over               |   nfcmrvl_fw_dnld_abort
> >     release_firmware          |    fw_dnld_over
> >      kfree(fw) //(1)          |     release_firmware
> >      ...                      |      kfree(fw) //(2)
> > 
> > The third situation is shown below:
> > 
> >        (Thread 1)               |       (Thread 2)
> > nfcmrvl_nci_recv_frame          |
> >  if(..->fw_download_in_progress)|
> >   nfcmrvl_fw_dnld_recv_frame    |
> >    queue_work                   |
> >                                 |
> > fw_dnld_rx_work                 | nfcmrvl_nci_unregister_dev
> >  fw_dnld_over                   |  nfcmrvl_fw_dnld_abort
> >   release_firmware              |   fw_dnld_over
> >    kfree(fw) //(1)              |    release_firmware
> >                                 |     kfree(fw) //(2)
> > 
> > The firmware struct is deallocated in position (1) and deallocated
> > in position (2) again.
> > 
> > The crash trace triggered by POC is like below:
> > 
> > [  122.640457] BUG: KASAN: double-free or invalid-free in fw_dnld_over+0x28/0xf0
> > [  122.640457] Call Trace:
> > [  122.640457]  <TASK>
> > [  122.640457]  kfree+0xb0/0x330
> > [  122.640457]  fw_dnld_over+0x28/0xf0
> > [  122.640457]  nfcmrvl_nci_unregister_dev+0x61/0x70
> > [  122.640457]  nci_uart_tty_close+0x87/0xd0
> > [  122.640457]  tty_ldisc_kill+0x3e/0x80
> > [  122.640457]  tty_ldisc_hangup+0x1b2/0x2c0
> > [  122.640457]  __tty_hangup.part.0+0x316/0x520
> > [  122.640457]  tty_release+0x200/0x670
> > [  122.640457]  __fput+0x110/0x410
> > [  122.640457]  task_work_run+0x86/0xd0
> > [  122.640457]  exit_to_user_mode_prepare+0x1aa/0x1b0
> > [  122.640457]  syscall_exit_to_user_mode+0x19/0x50
> > [  122.640457]  do_syscall_64+0x48/0x90
> > [  122.640457]  entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [  122.640457] RIP: 0033:0x7f68433f6beb
> > 
> > What's more, there are also use-after-free and null-ptr-deref bugs
> > in nfcmrvl_fw_dnld_start. If we deallocate firmware struct, gpio or
> > set null to the members of priv->fw_dnld in nfcmrvl_nci_unregister_dev,
> > then, we dereference firmware, gpio or the members of priv->fw_dnld in
> > nfcmrvl_fw_dnld_start, the UAF or NPD bugs will happen.
> > 
> > This patch reorders destructive operations after nci_unregister_device
> > to avoid the double-free, UAF and NPD bugs, as nci_unregister_device
> > is well synchronized and won't return if there is a running routine.
> > This was mentioned in commit 3e3b5dfcd16a ("NFC: reorder the logic in
> > nfc_{un,}register_device").
> > 
> > Fixes: 3194c6870158 ("NFC: nfcmrvl: add firmware download support")
> > Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
> > Reviewed-by: Lin Ma <linma@zju.edu.cn>
> 
> It's the first submission, how this review appeared?

I will remove the review tag.

> On the other hand, you already sent something similar, so is it a v2? I
> am sorry but this is very confusing. Looks like
> https://lore.kernel.org/all/20220425005718.33639-1-duoming@zju.edu.cn/
> but there is no changelog and commit description is different.

I am sorry the above link is just a test, I forget to remove "Cc: stable@vger.kernel.org".

> Please read:
> https://elixir.bootlin.com/linux/v5.18-rc4/source/Documentation/process/submitting-patches.rst
> 

I will send "[PATCH net V2] nfc: nfcmrvl: uart: reorder destructive operations in nfcmrvl_nci_unregister_dev to avoid bugs".

Best regards,
Duoming Zhou

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2022-04-25  9:17 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-25  3:10 [PATCH] drivers: nfc: nfcmrvl: reorder destructive operations in nfcmrvl_nci_unregister_dev to avoid bugs Duoming Zhou
2022-04-25  7:59 ` Krzysztof Kozlowski
2022-04-25  9:09   ` duoming

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.