[PATCH] usb: gadget: f_uac1_legacy: fix inverted NULL check after kstrndup()

[Xu Yang]

From: Xu Yang <xu.yang_2@xxxxxxx>

kstrndup() returns NULL on allocation failure. The condition was
checking 'if (tmp)' to detect failure, but this is inverted — it
would treat a successful allocation as an error and return -ENOMEM
while leaking the string, and proceed with a NULL pointer on failure.

Fix by changing the condition to 'if (!tmp)'.

Fixes: 0854611a19ae ("usb: gadget: f_uac1: add configfs support")
Cc: stable@xxxxxxxxxxxxxxx
Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
---
 drivers/usb/gadget/function/f_uac1_legacy.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/f_uac1_legacy.c b/drivers/usb/gadget/function/f_uac1_legacy.c
index 5d201a2e30e7..e9f2632ce785 100644
--- a/drivers/usb/gadget/function/f_uac1_legacy.c
+++ b/drivers/usb/gadget/function/f_uac1_legacy.c
@@ -914,7 +914,7 @@ static ssize_t f_uac1_opts_##name##_store(struct config_item *item,	\
 		goto end;						\
 									\
 	tmp = kstrndup(page, len, GFP_KERNEL);				\
-	if (tmp) {							\
+	if (!tmp) {							\
 		ret = -ENOMEM;						\
 		goto end;						\
 	}								\
-- 
2.34.1