This is a note to let you know that I've just added the patch titled nfc/nci: fix race with opening and closing to the 6.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfc-nci-fix-race-with-opening-and-closing.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 15d6780e4860a345c773de73165aa25c503cdb18 Author: Lin Ma <linma@xxxxxxxxxx> Date: Wed Nov 16 21:02:49 2022 +0800 nfc/nci: fix race with opening and closing [ Upstream commit 0ad6bded175e829c2ca261529c9dce39a32a042d ] Previously we leverage NCI_UNREG and the lock inside nci_close_device to prevent the race condition between opening a device and closing a device. However, it still has problem because a failed opening command will erase the NCI_UNREG flag and allow another opening command to bypass the status checking. This fix corrects that by making sure the NCI_UNREG is held. Reported-by: syzbot+43475bf3cfbd6e41f5b7@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 48b71a9e66c2 ("NFC: add NCI_UNREG flag to eliminate the race") Signed-off-by: Lin Ma <linma@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c index 6a193cce2a75..4ffdf2f45c44 100644 --- a/net/nfc/nci/core.c +++ b/net/nfc/nci/core.c @@ -542,7 +542,7 @@ static int nci_open_device(struct nci_dev *ndev) skb_queue_purge(&ndev->tx_q); ndev->ops->close(ndev); - ndev->flags = 0; + ndev->flags &= BIT(NCI_UNREG); } done: