diff mbox series

[v3] usb: typec: tcpm: Add IS_ERR_OR_NULL check for port->partner

Message ID 20230816083051.132480-1-hhhuuu@google.com (mailing list archive)
State Accepted
Commit 4987daf86c152ff882d51572d154ad12e4ff3a4b
Headers show
Series [v3] usb: typec: tcpm: Add IS_ERR_OR_NULL check for port->partner | expand

Commit Message

Jimmy Hu Aug. 16, 2023, 8:30 a.m. UTC
port->partner may be an error or NULL. This will cause a NULL pointer
dereference as below.

[91222.095236][  T319] typec port0: failed to register partner (-17)
...
[91225.061491][  T319] Unable to handle kernel NULL pointer dereference
at virtual address 000000000000039f
[91225.274642][  T319] pc : tcpm_pd_data_request+0x310/0x13fc
[91225.274646][  T319] lr : tcpm_pd_data_request+0x298/0x13fc
[91225.308067][  T319] Call trace:
[91225.308070][  T319]  tcpm_pd_data_request+0x310/0x13fc
[91225.308073][  T319]  tcpm_pd_rx_handler+0x100/0x9e8
[91225.355900][  T319]  kthread_worker_fn+0x178/0x58c
[91225.355902][  T319]  kthread+0x150/0x200
[91225.355905][  T319]  ret_from_fork+0x10/0x30

Add a check for port->partner to avoid dereferencing a NULL pointer.

Fixes: 5e1d4c49fbc8 ("usb: typec: tcpm: Determine common SVDM Version")
Signed-off-by: Jimmy Hu <hhhuuu@google.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Greg KH Aug. 16, 2023, 2:44 p.m. UTC | #1
On Wed, Aug 16, 2023 at 08:30:51AM +0000, Jimmy Hu wrote:
> port->partner may be an error or NULL. This will cause a NULL pointer
> dereference as below.
> 
> [91222.095236][  T319] typec port0: failed to register partner (-17)
> ...
> [91225.061491][  T319] Unable to handle kernel NULL pointer dereference
> at virtual address 000000000000039f
> [91225.274642][  T319] pc : tcpm_pd_data_request+0x310/0x13fc
> [91225.274646][  T319] lr : tcpm_pd_data_request+0x298/0x13fc
> [91225.308067][  T319] Call trace:
> [91225.308070][  T319]  tcpm_pd_data_request+0x310/0x13fc
> [91225.308073][  T319]  tcpm_pd_rx_handler+0x100/0x9e8
> [91225.355900][  T319]  kthread_worker_fn+0x178/0x58c
> [91225.355902][  T319]  kthread+0x150/0x200
> [91225.355905][  T319]  ret_from_fork+0x10/0x30
> 
> Add a check for port->partner to avoid dereferencing a NULL pointer.
> 
> Fixes: 5e1d4c49fbc8 ("usb: typec: tcpm: Determine common SVDM Version")
> Signed-off-by: Jimmy Hu <hhhuuu@google.com>
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 5639b9a1e0bf..ca9b1f3a38bc 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -1625,6 +1625,9 @@ static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
>  			if (PD_VDO_VID(p[0]) != USB_SID_PD)
>  				break;
>  
> +			if (IS_ERR_OR_NULL(port->partner))
> +				break;
> +
>  			if (PD_VDO_SVDM_VER(p[0]) < svdm_version) {
>  				typec_partner_set_svdm_version(port->partner,
>  							       PD_VDO_SVDM_VER(p[0]));
> -- 
> 2.41.0.694.ge786442a9b-goog
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- This looks like a new version of a previously submitted patch, but you
  did not list below the --- line any changes from the previous version.
  Please read the section entitled "The canonical patch format" in the
  kernel file, Documentation/process/submitting-patches.rst for what
  needs to be done here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot
diff mbox series

Patch

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 5639b9a1e0bf..ca9b1f3a38bc 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -1625,6 +1625,9 @@  static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
 			if (PD_VDO_VID(p[0]) != USB_SID_PD)
 				break;
 
+			if (IS_ERR_OR_NULL(port->partner))
+				break;
+
 			if (PD_VDO_SVDM_VER(p[0]) < svdm_version) {
 				typec_partner_set_svdm_version(port->partner,
 							       PD_VDO_SVDM_VER(p[0]));