[PATCH] usb: typec: thunderbolt: release a non-Thunderbolt cable plug

[PATCH] usb: typec: thunderbolt: release a non-Thunderbolt cable plug

[Wentao Liang]

tbt_ready() takes a reference on each cable plug with
typec_altmode_get_plug() and keeps it in tbt->plug[] for the lifetime of
the alternate mode.  When a plug reports an SVID other than Thunderbolt,
the loop breaks without storing the plug, so the reference taken for it
is never dropped.

Put that plug before leaving the loop on the SVID mismatch path.

Fixes: 100e25738659 ("usb: typec: Add driver for Thunderbolt 3 Alternate Mode")
Cc: stable@vger.kernel.org
Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/usb/typec/altmodes/thunderbolt.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/altmodes/thunderbolt.c b/drivers/usb/typec/altmodes/thunderbolt.c
index 2e1b1a1da7d9..fad48aae6751 100644
--- a/drivers/usb/typec/altmodes/thunderbolt.c
+++ b/drivers/usb/typec/altmodes/thunderbolt.c
@@ -340,8 +340,10 @@ static bool tbt_ready(struct typec_altmode *alt)
 		if (!plug)
 			continue;
 
-		if (plug->svid != USB_TYPEC_TBT_SID)
+		if (plug->svid != USB_TYPEC_TBT_SID) {
+			typec_altmode_put_plug(plug);
 			break;
+		}
 
 		plug->desc = "Thunderbolt3";
 		plug->cable_ops = &tbt_cable_ops;
-- 
2.34.1

Re: [PATCH] usb: typec: thunderbolt: release a non-Thunderbolt cable plug

[sashiko-bot]

> tbt_ready() takes a reference on each cable plug with
> typec_altmode_get_plug() and keeps it in tbt->plug[] for the lifetime of
> the alternate mode.  When a plug reports an SVID other than Thunderbolt,
> the loop breaks without storing the plug, so the reference taken for it
> is never dropped.
> 
> Put that plug before leaving the loop on the SVID mismatch path.
> 
> Fixes: 100e25738659 ("usb: typec: Add driver for Thunderbolt 3 Alternate Mode")
> Cc: stable@vger.kernel.org
> Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>

Sashiko has reviewed this patch and found no issues.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261104021516.1468625-1-vulab@iscas.ac.cn?part=1