[PATCH net v2 00/10] rxrpc: Miscellaneous fixes

[PATCH net v2 00/10] rxrpc: Miscellaneous fixes

[David Howells]

Here are some miscellaneous AF_RXRPC fixes for more stuff found by Sashiko[1][2]:

 (1) Reject ACKALL packets for calls not in Tx or immediate post-Tx state.

 (2) Fix connection leak from AF_RXRPC recvmsg userspace OOB handling.

 (3) Fix double unlock in AF_RXRPC recvmsg userspace OOB handling.

 (4) Fix AFS preallocate charge to flush the waitqueue after unlistening
     the socket so that any charging thread that does manage to get started
     will be waited for before socket destruction.

 (5) Fix AFS OOB notify handling to cancel in-progress OOB notification
     handling and then to flush the workqueue it's on.

 (6) Fix handling of apparent reply reception before initial transmission
     starts in client call.

 (7) Fix OOB challenge leak in cleanup on notification failure.

 (8) Fix infinite loop in recvmsg if OOB packet available, but no calls.

 (9) Fix notify vs recvmsg race where notify thinks the call is already
     queued.

(10) Fix MSG_PEEK call leak for calls with no content.

David

The patches can be found here also:

	http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=rxrpc-fixes

[1] https://sashiko.dev/#/patchset/20260609140911.838677-1-dhowells%40redhat.com
[2] https://sashiko.dev/#/patchset/20260616155749.2125907-1-dhowells%40redhat.com

Changes
=======
ver #2)
- Addressed the Sashiko review[2] of ver #1.
  - Added patches to fix more bugs that it found.
  - Adjusted AFS preallocate charge cleanup to only cancel the preallocate
    work item after unlistening rather than flushing the entire waitqueue
    (which may be waiting on DNS lookup).
  - 

David Howells (9):
  rxrpc: Fix leak of connection from OOB challenge
  rxrpc: Fix double unlock in rxrpc_recvmsg()
  afs: Fix further netns teardown to cancel the preallocation charger
  afs: Fix uncancelled rxrpc OOB message handler
  rxrpc: Fix the reception of a reply packet before data transmission
  rxrpc: Fix oob challenge leak in cleanup after notification failure
  rxrpc: Fix potential infinite loop in rxrpc_recvmsg()
  rxrpc: Fix socket notification race
  rxrpc: Fix leak of released call in recvmsg(MSG_PEEK)

Wyatt Feng (1):
  rxrpc: input: reject ACKALL outside transmit phase

 fs/afs/cm_security.c    |  3 ++-
 fs/afs/rxrpc.c          | 10 +++++++++-
 net/rxrpc/ar-internal.h |  4 ++--
 net/rxrpc/conn_event.c  |  9 +++++++--
 net/rxrpc/input.c       | 29 +++++++++++++++++++++++++----
 net/rxrpc/oob.c         | 12 ++++++++++--
 net/rxrpc/recvmsg.c     | 10 ++++------
 7 files changed, 59 insertions(+), 18 deletions(-)

[PATCH net v2 01/10] rxrpc: input: reject ACKALL outside transmit phase

[David Howells]

From: Wyatt Feng <bronzed_45_vested@icloud.com>

rxrpc_input_ackall() accepts ACKALL packets without checking whether
the call is in a state that can legitimately have outstanding transmit
buffers.  A forged ACKALL can therefore reach a new service call in
RXRPC_CALL_SERVER_RECV_REQUEST before any reply packets have been
queued.

In that state call->tx_top is zero and call->tx_queue is NULL, so
rxrpc_rotate_tx_window() dereferences a NULL txqueue and triggers a
null-pointer dereference.

Fix rxrpc_input_ackall() to mirror the transmit-state gating already
used for normal ACK processing, and ignore ACKALL when there is no
outstanding transmit window to rotate.

Fixes: b341a0263b1b ("rxrpc: Implement progressive transmission queue struct")
Cc: stable@vger.kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Assisted-by: Codex:GPT-5.4
Signed-off-by: Wyatt Feng <bronzed_45_vested@icloud.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
---
 net/rxrpc/input.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index ce761466b02d..37881dffa898 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -1214,8 +1214,22 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
 static void rxrpc_input_ackall(struct rxrpc_call *call, struct sk_buff *skb)
 {
 	struct rxrpc_ack_summary summary = { 0 };
+	rxrpc_seq_t top = READ_ONCE(call->tx_top);
+
+	switch (__rxrpc_call_state(call)) {
+	case RXRPC_CALL_CLIENT_SEND_REQUEST:
+	case RXRPC_CALL_CLIENT_AWAIT_REPLY:
+	case RXRPC_CALL_SERVER_SEND_REPLY:
+	case RXRPC_CALL_SERVER_AWAIT_ACK:
+		break;
+	default:
+		return;
+	}
+
+	if (call->tx_bottom == top)
+		return;
 
-	if (rxrpc_rotate_tx_window(call, call->tx_top, &summary))
+	if (rxrpc_rotate_tx_window(call, top, &summary))
 		rxrpc_end_tx_phase(call, false, rxrpc_eproto_unexpected_ackall);
 }
 

[PATCH net v2 02/10] rxrpc: Fix leak of connection from OOB challenge

[David Howells]

Fix leak of connection object from OOB challenge queue when response is
provided by userspace.

Fixes: 5800b1cf3fd8 ("rxrpc: Allow CHALLENGEs to the passed to the app for a RESPONSE")
Link: https://sashiko.dev/#/patchset/20260609140911.838677-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/oob.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/rxrpc/oob.c b/net/rxrpc/oob.c
index 05ca9c1faa57..3318c8bd82ad 100644
--- a/net/rxrpc/oob.c
+++ b/net/rxrpc/oob.c
@@ -210,6 +210,11 @@ static int rxrpc_respond_to_oob(struct rxrpc_sock *rx,
 		break;
 	}
 
+	switch (skb->mark) {
+	case RXRPC_OOB_CHALLENGE:
+		rxrpc_put_connection(sp->chall.conn, rxrpc_conn_put_oob);
+		break;
+	}
 	rxrpc_free_skb(skb, rxrpc_skb_put_oob);
 	return ret;
 }

[PATCH net v2 03/10] rxrpc: Fix double unlock in rxrpc_recvmsg()

[David Howells]

Fix a double unlock in rxrpc_recvmsg() when dealing with OOB messages.

Fixes: 5800b1cf3fd8 ("rxrpc: Allow CHALLENGEs to the passed to the app for a RESPONSE")
Link: https://sashiko.dev/#/patchset/20260609140911.838677-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/recvmsg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 82614cbdb60f..39a03684432d 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -471,7 +471,7 @@ int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 		release_sock(&rx->sk);
 		if (ret == -EAGAIN)
 			goto try_again;
-		goto error_no_call;
+		goto error_trace;
 	}
 
 	/* Find the next call and dequeue it if we're not just peeking.  If we

[PATCH net v2 04/10] afs: Fix further netns teardown to cancel the preallocation charger

[David Howells]

When an afs network namespace is torn down, it cancels and waits for the
work item that keeps the preallocated rxrpc call/conn/peer queue charged
before disabling incoming (i.e. listen 0), but there's a small window in
which it can be requeued by an incoming call wending through the I/O
thread.

Fix this by flushing the workqueue on which the charger runs after reducing
the listen backlog to zero.

Fixes: 47694fbc9d24 ("afs: Fix netns teardown to cancel the preallocation charger")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://sashiko.dev/#/patchset/20260609140911.838677-1-dhowells%40redhat.com
cc: Li Daming <d4n.for.sec@gmail.com>
cc: Ren Wei <n05ec@lzu.edu.cn>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 fs/afs/rxrpc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index d5cfd24e815b..6714a189d58f 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -128,8 +128,13 @@ void afs_close_socket(struct afs_net *net)
 	_enter("");
 
 	cancel_work_sync(&net->charge_preallocation_work);
+	/* Future work items should now see ->live is false. */
+
 	kernel_listen(net->socket, 0);
+
+	/* Make sure work items are no longer running. */
 	flush_workqueue(afs_async_calls);
+	cancel_work_sync(&net->charge_preallocation_work);
 
 	if (net->spare_incoming_call) {
 		afs_put_call(net->spare_incoming_call);

[PATCH net v2 05/10] afs: Fix uncancelled rxrpc OOB message handler

[David Howells]

Fix AFS to cancel its OOB message processing (typically to respond to
security challenges).  Also move OOB message processing to afs_wq so that
it's also waited for and make the OOB handler just return if the net
namespace is no longer live.

Fixes: 5800b1cf3fd8 ("rxrpc: Allow CHALLENGEs to the passed to the app for a RESPONSE")
Link: https://sashiko.dev/#/patchset/20260609140911.838677-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Li Daming <d4n.for.sec@gmail.com>
cc: Ren Wei <n05ec@lzu.edu.cn>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 fs/afs/cm_security.c | 3 ++-
 fs/afs/rxrpc.c       | 5 ++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/afs/cm_security.c b/fs/afs/cm_security.c
index edcbd249d202..103168c70dd4 100644
--- a/fs/afs/cm_security.c
+++ b/fs/afs/cm_security.c
@@ -101,7 +101,8 @@ void afs_process_oob_queue(struct work_struct *work)
 	struct sk_buff *oob;
 	enum rxrpc_oob_type type;
 
-	while ((oob = rxrpc_kernel_dequeue_oob(net->socket, &type))) {
+	while (READ_ONCE(net->live) &&
+	       (oob = rxrpc_kernel_dequeue_oob(net->socket, &type))) {
 		switch (type) {
 		case RXRPC_OOB_CHALLENGE:
 			afs_respond_to_challenge(oob);
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 6714a189d58f..e8af2a661440 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -128,6 +128,7 @@ void afs_close_socket(struct afs_net *net)
 	_enter("");
 
 	cancel_work_sync(&net->charge_preallocation_work);
+	cancel_work_sync(&net->rx_oob_work);
 	/* Future work items should now see ->live is false. */
 
 	kernel_listen(net->socket, 0);
@@ -148,6 +149,7 @@ void afs_close_socket(struct afs_net *net)
 
 	kernel_sock_shutdown(net->socket, SHUT_RDWR);
 	flush_workqueue(afs_async_calls);
+	cancel_work_sync(&net->rx_oob_work);
 	net->socket->sk->sk_user_data = NULL;
 	sock_release(net->socket);
 	key_put(net->fs_cm_token_key);
@@ -989,5 +991,6 @@ static void afs_rx_notify_oob(struct sock *sk, struct sk_buff *oob)
 {
 	struct afs_net *net = sk->sk_user_data;
 
-	schedule_work(&net->rx_oob_work);
+	if (net->live)
+		queue_work(afs_wq, &net->rx_oob_work);
 }

[PATCH net v2 06/10] rxrpc: Fix the reception of a reply packet before data transmission

[David Howells]

Fix rxrpc_receiving_reply() to handle the reception of an apparent reply
DATA packet before rxrpc has had a chance to send any request DATA packets
on a client call by checking to see if the call has been exposed yet by
sending the first packet.

Without this, rxrpc_rotate_tx_window() might oops.

Also fix rxrpc_rotate_tx_window() to handle the Tx queue being empty by
changing the do...while loop into a while loop, just in case a call is
abnormally terminated by an early reply before the last request packet is
transmitted.

Fixes: b341a0263b1b ("rxrpc: Implement progressive transmission queue struct")
Link: https://sashiko.dev/#/patchset/20260616155749.2125907-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/input.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 37881dffa898..01ccd2d2fe92 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -247,7 +247,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
 		tq = call->tx_queue;
 	}
 
-	do {
+	while (before_eq(seq, to)) {
 		unsigned int ix = seq - call->tx_qbase;
 
 		_debug("tq=%x seq=%x i=%d f=%x", tq->qbase, seq, ix, tq->bufs[ix]->flags);
@@ -317,8 +317,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
 				break;
 			}
 		}
-
-	} while (before_eq(seq, to));
+	}
 
 	if (trace)
 		trace_rxrpc_rack_update(call, summary);
@@ -392,6 +391,14 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call)
 		trace_rxrpc_timer_can(call, rxrpc_timer_trace_delayed_ack);
 	}
 
+	/* Deal with an apparent reply coming in before we've got the request
+	 * queued or transmitted.
+	 */
+	if (!test_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
+		rxrpc_proto_abort(call, top, rxrpc_eproto_early_reply);
+		return false;
+	}
+
 	if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {
 		if (!rxrpc_rotate_tx_window(call, top, &summary)) {
 			rxrpc_proto_abort(call, top, rxrpc_eproto_early_reply);

[PATCH net v2 07/10] rxrpc: Fix oob challenge leak in cleanup after notification failure

[David Howells]

Fix rxrpc_notify_socket_oob() to return an indication of failure in the
event that it failed to queue a packet and fix rxrpc_post_challenge() to
clean up the connection ref in such an event.

Fixes: 5800b1cf3fd8 ("rxrpc: Allow CHALLENGEs to the passed to the app for a RESPONSE")
Link: https://sashiko.dev/#/patchset/20260616155749.2125907-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/ar-internal.h | 4 ++--
 net/rxrpc/conn_event.c  | 9 +++++++--
 net/rxrpc/oob.c         | 7 +++++--
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 98f2165159d7..ead3419f08b7 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -1355,9 +1355,9 @@ static inline struct rxrpc_net *rxrpc_net(struct net *net)
 }
 
 /*
- * out_of_band.c
+ * oob.c
  */
-void rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb);
+bool rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb);
 void rxrpc_add_pending_oob(struct rxrpc_sock *rx, struct sk_buff *skb);
 int rxrpc_sendmsg_oob(struct rxrpc_sock *rx, struct msghdr *msg, size_t len);
 
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index c96ca615b787..611c790bc6d0 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -436,7 +436,7 @@ static bool rxrpc_post_challenge(struct rxrpc_connection *conn,
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	struct rxrpc_call *call = NULL;
 	struct rxrpc_sock *rx;
-	bool respond = false;
+	bool respond = false, queued = false;
 
 	sp->chall.conn =
 		rxrpc_get_connection(conn, rxrpc_conn_get_challenge_input);
@@ -472,8 +472,13 @@ static bool rxrpc_post_challenge(struct rxrpc_connection *conn,
 	}
 
 	if (call)
-		rxrpc_notify_socket_oob(call, skb);
+		queued = rxrpc_notify_socket_oob(call, skb);
 	rcu_read_unlock();
+	if (call && !queued) {
+		rxrpc_put_connection(conn, rxrpc_conn_put_challenge_input);
+		sp->chall.conn = NULL;
+		return false;
+	}
 
 	if (!call)
 		rxrpc_post_packet_to_conn(conn, skb);
diff --git a/net/rxrpc/oob.c b/net/rxrpc/oob.c
index 3318c8bd82ad..c80ee2487d09 100644
--- a/net/rxrpc/oob.c
+++ b/net/rxrpc/oob.c
@@ -32,11 +32,12 @@ struct rxrpc_oob_params {
  * Post an out-of-band message for attention by the socket or kernel service
  * associated with a reference call.
  */
-void rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb)
+bool rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	struct rxrpc_sock *rx;
 	struct sock *sk;
+	bool queued = false;
 
 	rcu_read_lock();
 
@@ -49,6 +50,7 @@ void rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb)
 			skb->skb_mstamp_ns = rx->oob_id_counter++;
 			rxrpc_get_skb(skb, rxrpc_skb_get_post_oob);
 			skb_queue_tail(&rx->recvmsg_oobq, skb);
+			queued = true;
 
 			trace_rxrpc_notify_socket(call->debug_id, sp->hdr.serial);
 			if (rx->app_ops)
@@ -56,11 +58,12 @@ void rxrpc_notify_socket_oob(struct rxrpc_call *call, struct sk_buff *skb)
 		}
 
 		spin_unlock_irq(&rx->recvmsg_lock);
-		if (!rx->app_ops && !sock_flag(sk, SOCK_DEAD))
+		if (queued && !rx->app_ops && !sock_flag(sk, SOCK_DEAD))
 			sk->sk_data_ready(sk);
 	}
 
 	rcu_read_unlock();
+	return queued;
 }
 
 /*

[PATCH net v2 08/10] rxrpc: Fix potential infinite loop in rxrpc_recvmsg()

[David Howells]

Fix the wait in rxrpc_recvmsg() also take check the oob queue.

Fixes: 5800b1cf3fd8 ("rxrpc: Allow CHALLENGEs to the passed to the app for a RESPONSE")
Link: https://sashiko.dev/#/patchset/20260616155749.2125907-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/recvmsg.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 39a03684432d..f382a47c6eb0 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -438,7 +438,8 @@ int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 		return -EAGAIN;
 	}
 
-	if (list_empty(&rx->recvmsg_q)) {
+	if (list_empty(&rx->recvmsg_q) &&
+	    skb_queue_empty_lockless(&rx->recvmsg_oobq)) {
 		ret = -EWOULDBLOCK;
 		if (timeo == 0) {
 			call = NULL;

[PATCH net v2 09/10] rxrpc: Fix socket notification race

[David Howells]

There's a race between rxrpc_recvmsg() and rxrpc_notify_socket(), whereby
the latter's attempt to avoid disabling interrupts and taking the socket's
recvmsg_lock if the call is already queued may happen simultaneously with
the former's discarding of a call that has nothing queued.

Fix this by removing the shortcut.  Note that this only affects userspace's
use of AF_RXRPC; the AFS filesystem driver doesn't use the socket queue.

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Link: https://sashiko.dev/#/patchset/20260616155749.2125907-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/recvmsg.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index f382a47c6eb0..9962e135cb73 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -27,8 +27,6 @@ void rxrpc_notify_socket(struct rxrpc_call *call)
 
 	_enter("%d", call->debug_id);
 
-	if (!list_empty(&call->recvmsg_link))
-		return;
 	if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) {
 		rxrpc_see_call(call, rxrpc_call_see_notify_released);
 		return;

[PATCH net v2 10/10] rxrpc: Fix leak of released call in recvmsg(MSG_PEEK)

[David Howells]

Fix rxrpc_recvmsg() to also drop the ref it holds on an already-released
call if MSG_PEEK is in force (the function holds a ref on the call
irrespective of whether MSG_PEEK is specified or not).

Link: https://sashiko.dev/#/patchset/20260616155749.2125907-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Fixes: 962fb1f651c2 ("rxrpc: Fix recv-recv race of completed call")
---
 net/rxrpc/recvmsg.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 9962e135cb73..efcba4b2e74f 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -529,8 +529,7 @@ int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) {
 		rxrpc_see_call(call, rxrpc_call_see_already_released);
 		mutex_unlock(&call->user_mutex);
-		if (!(flags & MSG_PEEK))
-			rxrpc_put_call(call, rxrpc_call_put_recvmsg);
+		rxrpc_put_call(call, rxrpc_call_put_recvmsg);
 		goto try_again;
 	}