From: Jeremy Kerr <jk@xxxxxxxxxxxxxxxxxxxx>
[ Upstream commit 5f41ae6fca9d40ab3cb9b0507931ef7a9b3ea50b ]
Currently, we delete the key expiry timer (in sk->close) before
unhashing the sk. This means that another thread may find the sk through
its presence on the key list, and re-queue the timer.
This change moves the timer deletion to the unhash, after we have made
the key no longer observable, so the timer cannot be re-queued.
Fixes: 7b14e15ae6f4 ("mctp: Implement a timeout for tags")
Signed-off-by: Jeremy Kerr <jk@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/mctp/af_mctp.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index fc9e728b6333..fb6ae3110528 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -544,9 +544,6 @@ static int mctp_sk_init(struct sock *sk)
static void mctp_sk_close(struct sock *sk, long timeout)
{
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
-
- del_timer_sync(&msk->key_expiry);
sk_common_release(sk);
}
@@ -581,6 +578,12 @@ static void mctp_sk_unhash(struct sock *sk)
__mctp_key_remove(key, net, fl2, MCTP_TRACE_KEY_CLOSED);
}
spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
+
+ /* Since there are no more tag allocations (we have removed all of the
+ * keys), stop any pending expiry events. the timer cannot be re-queued
+ * as the sk is no longer observable
+ */
+ del_timer_sync(&msk->key_expiry);
}
static struct proto mctp_proto = {
--
2.39.0
