2023-05-13 22:05:09

by Fedor Pchelkin

[permalink] [raw]
Subject: [PATCH] wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

A bad USB device is able to construct a service connection response
message with target endpoint being ENDPOINT0 which is reserved for
HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
services.

Reject such service connection responses.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
Reported-by: [email protected]
Signed-off-by: Fedor Pchelkin <[email protected]>
---
drivers/net/wireless/ath/ath9k/htc_hst.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireless/ath/ath9k/htc_hst.c
index fe62ff668f75..a15d8d80df87 100644
--- a/drivers/net/wireless/ath/ath9k/htc_hst.c
+++ b/drivers/net/wireless/ath/ath9k/htc_hst.c
@@ -114,7 +114,7 @@ static void htc_process_conn_rsp(struct htc_target *target,

if (svc_rspmsg->status == HTC_SERVICE_SUCCESS) {
epid = svc_rspmsg->endpoint_id;
- if (epid < 0 || epid >= ENDPOINT_MAX)
+ if (epid <= 0 || epid >= ENDPOINT_MAX)
return;

service_id = be16_to_cpu(svc_rspmsg->service_id);
--
2.34.1



2023-05-15 12:17:23

by Toke Høiland-Jørgensen

[permalink] [raw]
Subject: Re: [PATCH] wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

Fedor Pchelkin <[email protected]> writes:

> A bad USB device is able to construct a service connection response
> message with target endpoint being ENDPOINT0 which is reserved for
> HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
> services.
>
> Reject such service connection responses.
>
> Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
>
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-by: [email protected]
> Signed-off-by: Fedor Pchelkin <[email protected]>
> ---
> drivers/net/wireless/ath/ath9k/htc_hst.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireless/ath/ath9k/htc_hst.c
> index fe62ff668f75..a15d8d80df87 100644
> --- a/drivers/net/wireless/ath/ath9k/htc_hst.c
> +++ b/drivers/net/wireless/ath/ath9k/htc_hst.c
> @@ -114,7 +114,7 @@ static void htc_process_conn_rsp(struct htc_target *target,
>
> if (svc_rspmsg->status == HTC_SERVICE_SUCCESS) {
> epid = svc_rspmsg->endpoint_id;
> - if (epid < 0 || epid >= ENDPOINT_MAX)
> + if (epid <= 0 || epid >= ENDPOINT_MAX)
> return;

Hmm, I think we should use the ENDPOINT0 constant here, then, and maybe
add a comment above explaining that it's reserved?

-Toke

2023-05-16 15:07:26

by Fedor Pchelkin

[permalink] [raw]
Subject: [PATCH v2] wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

A bad USB device is able to construct a service connection response
message with target endpoint being ENDPOINT0 which is reserved for
HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
services.

Reject such service connection responses.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
Reported-by: [email protected]
Signed-off-by: Fedor Pchelkin <[email protected]>
---
v2: per Toke's remark, use ENDPOINT0 macro and give a comment explaining
why it should be checked.

drivers/net/wireless/ath/ath9k/htc_hst.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireless/ath/ath9k/htc_hst.c
index fe62ff668f75..99667aba289d 100644
--- a/drivers/net/wireless/ath/ath9k/htc_hst.c
+++ b/drivers/net/wireless/ath/ath9k/htc_hst.c
@@ -114,7 +114,13 @@ static void htc_process_conn_rsp(struct htc_target *target,

if (svc_rspmsg->status == HTC_SERVICE_SUCCESS) {
epid = svc_rspmsg->endpoint_id;
- if (epid < 0 || epid >= ENDPOINT_MAX)
+
+ /* Check that the received epid for the endpoint to attach
+ * a new service is valid. ENDPOINT0 can't be used here as it
+ * is already reserved for HTC_CTRL_RSVD_SVC service and thus
+ * should not be modified.
+ */
+ if (epid <= ENDPOINT0 || epid >= ENDPOINT_MAX)
return;

service_id = be16_to_cpu(svc_rspmsg->service_id);
--
2.34.1


2023-05-16 19:56:15

by Toke Høiland-Jørgensen

[permalink] [raw]
Subject: Re: [PATCH v2] wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

Fedor Pchelkin <[email protected]> writes:

> A bad USB device is able to construct a service connection response
> message with target endpoint being ENDPOINT0 which is reserved for
> HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
> services.
>
> Reject such service connection responses.
>
> Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
>
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-by: [email protected]
> Signed-off-by: Fedor Pchelkin <[email protected]>

Acked-by: Toke Høiland-Jørgensen <[email protected]>

2023-05-25 17:14:15

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH v2] wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

Fedor Pchelkin <[email protected]> wrote:

> A bad USB device is able to construct a service connection response
> message with target endpoint being ENDPOINT0 which is reserved for
> HTC_CTRL_RSVD_SVC and should not be modified to be used for any other
> services.
>
> Reject such service connection responses.
>
> Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
>
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-by: [email protected]
> Signed-off-by: Fedor Pchelkin <[email protected]>
> Acked-by: Toke Høiland-Jørgensen <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

061b0cb9327b wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches