This is a note to let you know that I've just added the patch titled
rxrpc: Fix overlapping ACK accounting
to the 5.18-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:
rxrpc-fix-overlapping-ack-accounting.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d2f6e66d173bfc5c6e5bd595ae8eeaf232de13dd
Author: David Howells <dhowells@xxxxxxxxxx>
Date: Sat May 21 09:03:18 2022 +0100
rxrpc: Fix overlapping ACK accounting
[ Upstream commit 8940ba3cfe4841928777fd45eaa92051522c7f0c ]
Fix accidental overlapping of Rx-phase ACK accounting with Tx-phase ACK
accounting through variables shared between the two. call->acks_* members
refer to ACKs received in the Tx phase and call->ackr_* members to ACKs
sent/to be sent during the Rx phase.
Fixes: 1a2391c30c0b ("rxrpc: Fix detection of out of order acks")
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Jeffrey Altman <jaltman@xxxxxxxxxxxx>
cc: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
cc: linux-afs@xxxxxxxxxxxxxxxxxxx
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 422558d50571..cc1fe6d00eca 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -676,10 +676,9 @@ struct rxrpc_call {
spinlock_t input_lock; /* Lock for packet input to this call */
- /* receive-phase ACK management */
+ /* Receive-phase ACK management (ACKs we send). */
u8 ackr_reason; /* reason to ACK */
rxrpc_serial_t ackr_serial; /* serial of packet being ACK'd */
- rxrpc_serial_t ackr_first_seq; /* first sequence number received */
rxrpc_seq_t ackr_prev_seq; /* previous sequence number received */
rxrpc_seq_t ackr_consumed; /* Highest packet shown consumed */
rxrpc_seq_t ackr_seen; /* Highest packet shown seen */
@@ -692,8 +691,10 @@ struct rxrpc_call {
#define RXRPC_CALL_RTT_AVAIL_MASK 0xf
#define RXRPC_CALL_RTT_PEND_SHIFT 8
- /* transmission-phase ACK management */
+ /* Transmission-phase ACK management (ACKs we've received). */
ktime_t acks_latest_ts; /* Timestamp of latest ACK received */
+ rxrpc_seq_t acks_first_seq; /* first sequence number received */
+ rxrpc_seq_t acks_prev_seq; /* previous sequence number received */
rxrpc_seq_t acks_lowest_nak; /* Lowest NACK in the buffer (or ==tx_hard_ack) */
rxrpc_seq_t acks_lost_top; /* tx_top at the time lost-ack ping sent */
rxrpc_serial_t acks_lost_ping; /* Serial number of probe ACK */
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 67d3eba60dc7..3da33b5c13b2 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -812,7 +812,7 @@ static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks,
static bool rxrpc_is_ack_valid(struct rxrpc_call *call,
rxrpc_seq_t first_pkt, rxrpc_seq_t prev_pkt)
{
- rxrpc_seq_t base = READ_ONCE(call->ackr_first_seq);
+ rxrpc_seq_t base = READ_ONCE(call->acks_first_seq);
if (after(first_pkt, base))
return true; /* The window advanced */
@@ -820,7 +820,7 @@ static bool rxrpc_is_ack_valid(struct rxrpc_call *call,
if (before(first_pkt, base))
return false; /* firstPacket regressed */
- if (after_eq(prev_pkt, call->ackr_prev_seq))
+ if (after_eq(prev_pkt, call->acks_prev_seq))
return true; /* previousPacket hasn't regressed. */
/* Some rx implementations put a serial number in previousPacket. */
@@ -933,8 +933,8 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
/* Discard any out-of-order or duplicate ACKs (outside lock). */
if (!rxrpc_is_ack_valid(call, first_soft_ack, prev_pkt)) {
trace_rxrpc_rx_discard_ack(call->debug_id, ack_serial,
- first_soft_ack, call->ackr_first_seq,
- prev_pkt, call->ackr_prev_seq);
+ first_soft_ack, call->acks_first_seq,
+ prev_pkt, call->acks_prev_seq);
return;
}
@@ -949,14 +949,14 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
/* Discard any out-of-order or duplicate ACKs (inside lock). */
if (!rxrpc_is_ack_valid(call, first_soft_ack, prev_pkt)) {
trace_rxrpc_rx_discard_ack(call->debug_id, ack_serial,
- first_soft_ack, call->ackr_first_seq,
- prev_pkt, call->ackr_prev_seq);
+ first_soft_ack, call->acks_first_seq,
+ prev_pkt, call->acks_prev_seq);
goto out;
}
call->acks_latest_ts = skb->tstamp;
- call->ackr_first_seq = first_soft_ack;
- call->ackr_prev_seq = prev_pkt;
+ call->acks_first_seq = first_soft_ack;
+ call->acks_prev_seq = prev_pkt;
/* Parse rwind and mtu sizes if provided. */
if (buf.info.rxMTU)
