Commit 7e8cdc97148c ("nfc: Add KCOV annotations") added
kcov_remote_start_common()/kcov_remote_stop() pair into nci_rx_work(),
with an assumption that kcov_remote_stop() is called upon continue of
the for loop. But commit d24b03535e5e ("nfc: nci: Fix uninit-value in
nci_dev_up and nci_ntf_packet") forgot to call kcov_remote_stop() before
break of the for loop.

Reported-by: syzbot <syzbot+0438378d6f157baae1a2@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=0438378d6f157baae1a2
Fixes: d24b03535e5e ("nfc: nci: Fix uninit-value in nci_dev_up and nci_ntf_packet")
Debugged-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
---
 net/nfc/nci/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c
index 0d26c8ec9993..b133dc55304c 100644
--- a/net/nfc/nci/core.c
+++ b/net/nfc/nci/core.c
@@ -1518,6 +1518,7 @@ static void nci_rx_work(struct work_struct *work)
 
 		if (!nci_plen(skb->data)) {
 			kfree_skb(skb);
+			kcov_remote_stop();
 			break;
 		}
 
-- 
2.34.1

On 05/05/2024 12:36, Tetsuo Handa wrote:
> Commit 7e8cdc97148c ("nfc: Add KCOV annotations") added
> kcov_remote_start_common()/kcov_remote_stop() pair into nci_rx_work(),
> with an assumption that kcov_remote_stop() is called upon continue of
> the for loop. But commit d24b03535e5e ("nfc: nci: Fix uninit-value in
> nci_dev_up and nci_ntf_packet") forgot to call kcov_remote_stop() before
> break of the for loop.
> 
> Reported-by: syzbot <syzbot+0438378d6f157baae1a2@syzkaller.appspotmail.com>
> Closes: https://syzkaller.appspot.com/bug?extid=0438378d6f157baae1a2
> Fixes: d24b03535e5e ("nfc: nci: Fix uninit-value in nci_dev_up and nci_ntf_packet")
> Debugged-by: Andrey Konovalov <andreyknvl@gmail.com>
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof