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| author | Lin Ma <linma@zju.edu.cn> | 2022-11-16 16:02:49 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-12-08 13:18:29 +0300 |
| commit | 97ca66a019150084f707f2ab80d1ba205fcac693 (patch) | |
| tree | 303439148703af19092632fe0fbac8d1b3234020 /net/nfc | |
| parent | 0ba4118035af7da10096e3a25921dd137a3eab83 (diff) | |
| download | linux-97ca66a019150084f707f2ab80d1ba205fcac693.tar.xz | |
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@syzkaller.appspotmail.com
Fixes: 48b71a9e66c2 ("NFC: add NCI_UNREG flag to eliminate the race")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/nfc')
| -rw-r--r-- | net/nfc/nci/core.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c index 0580e5326641..66608e6c5b0e 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: |