From nobody Thu Feb 12 04:48:14 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 42490C77B61 for ; Fri, 28 Apr 2023 20:29:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346610AbjD1U3Y (ORCPT ); Fri, 28 Apr 2023 16:29:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346624AbjD1U3F (ORCPT ); Fri, 28 Apr 2023 16:29:05 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 88F8B2728 for ; Fri, 28 Apr 2023 13:28:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1682713693; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=41KUBQaFistzCqjFah0QVDYkKS+WNIdy9b94n5s+HCs=; b=M1xAVGJqhnDUlT4M8Y6sE/HjHtCRL8wf7J6gLkI+C0EBD78PhTB+hvnCTVAKrVXCFIlgjq GdlElXEcvfIGWqZu7BUqkZ9EZe1jhwzn4mZ8tspkvR+17e8Iu2EdHcKVYS3lBwJu9nWAV2 W2I3EIsutAeuccsGBFRpWyqpUgII3a8= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-158-hO9dkLOQO523hDB9GezRGw-1; Fri, 28 Apr 2023 16:28:07 -0400 X-MC-Unique: hO9dkLOQO523hDB9GezRGw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AFD4FA0F385; Fri, 28 Apr 2023 20:28:06 +0000 (UTC) Received: from warthog.procyon.org.uk.com (unknown [10.42.28.174]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9D9002166B4F; Fri, 28 Apr 2023 20:28:05 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , Marc Dionne , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH net 3/3] rxrpc: Fix timeout of a call that hasn't yet been granted a channel Date: Fri, 28 Apr 2023 21:27:56 +0100 Message-Id: <20230428202756.1186269-4-dhowells@redhat.com> In-Reply-To: <20230428202756.1186269-1-dhowells@redhat.com> References: <20230428202756.1186269-1-dhowells@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" afs_make_call() calls rxrpc_kernel_begin_call() to begin a call (which may get stalled in the background waiting for a connection to become available); it then calls rxrpc_kernel_set_max_life() to set the timeouts - but that starts the call timer so the call timer might then expire before we get a connection assigned - leading to the following oops if the call stalled: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... CPU: 1 PID: 5111 Comm: krxrpcio/0 Not tainted 6.3.0-rc7-build3+ #701 RIP: 0010:rxrpc_alloc_txbuf+0xc0/0x157 ... Call Trace: rxrpc_send_ACK+0x50/0x13b rxrpc_input_call_event+0x16a/0x67d rxrpc_io_thread+0x1b6/0x45f ? _raw_spin_unlock_irqrestore+0x1f/0x35 ? rxrpc_input_packet+0x519/0x519 kthread+0xe7/0xef ? kthread_complete_and_exit+0x1b/0x1b ret_from_fork+0x22/0x30 Fix this by noting the timeouts in struct rxrpc_call when the call is created. The timer will be started when the first packet is transmitted. It shouldn't be possible to trigger this directly from userspace through AF_RXRPC as sendmsg() will return EBUSY if the call is in the waiting-for-conn state if it dropped out of the wait due to a signal. Fixes: 9d35d880e0e4 ("rxrpc: Move client call connection to the I/O thread") Reported-by: Marc Dionne Signed-off-by: David Howells cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: linux-kernel@vger.kernel.org --- fs/afs/afs.h | 4 ++-- fs/afs/internal.h | 2 +- fs/afs/rxrpc.c | 8 +++----- include/net/af_rxrpc.h | 21 +++++++++++---------- net/rxrpc/af_rxrpc.c | 3 +++ net/rxrpc/ar-internal.h | 1 + net/rxrpc/call_object.c | 9 ++++++++- net/rxrpc/sendmsg.c | 1 + 8 files changed, 30 insertions(+), 19 deletions(-) diff --git a/fs/afs/afs.h b/fs/afs/afs.h index 432cb4b23961..81815724db6c 100644 --- a/fs/afs/afs.h +++ b/fs/afs/afs.h @@ -19,8 +19,8 @@ #define AFSPATHMAX 1024 /* Maximum length of a pathname plus NUL */ #define AFSOPAQUEMAX 1024 /* Maximum length of an opaque field */ =20 -#define AFS_VL_MAX_LIFESPAN (120 * HZ) -#define AFS_PROBE_MAX_LIFESPAN (30 * HZ) +#define AFS_VL_MAX_LIFESPAN 120 +#define AFS_PROBE_MAX_LIFESPAN 30 =20 typedef u64 afs_volid_t; typedef u64 afs_vnodeid_t; diff --git a/fs/afs/internal.h b/fs/afs/internal.h index ad8523d0d038..68ae91d21b57 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -128,7 +128,7 @@ struct afs_call { spinlock_t state_lock; int error; /* error code */ u32 abort_code; /* Remote abort ID or 0 */ - unsigned int max_lifespan; /* Maximum lifespan to set if not 0 */ + unsigned int max_lifespan; /* Maximum lifespan in secs to set if not 0 */ unsigned request_size; /* size of request data */ unsigned reply_max; /* maximum size of reply */ unsigned count2; /* count used in unmarshalling */ diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c index e08b850c3e6d..ed1644e7683f 100644 --- a/fs/afs/rxrpc.c +++ b/fs/afs/rxrpc.c @@ -335,7 +335,9 @@ void afs_make_call(struct afs_addr_cursor *ac, struct a= fs_call *call, gfp_t gfp) /* create a call */ rxcall =3D rxrpc_kernel_begin_call(call->net->socket, srx, call->key, (unsigned long)call, - tx_total_len, gfp, + tx_total_len, + call->max_lifespan, + gfp, (call->async ? afs_wake_up_async_call : afs_wake_up_call_waiter), @@ -350,10 +352,6 @@ void afs_make_call(struct afs_addr_cursor *ac, struct = afs_call *call, gfp_t gfp) } =20 call->rxcall =3D rxcall; - - if (call->max_lifespan) - rxrpc_kernel_set_max_life(call->net->socket, rxcall, - call->max_lifespan); call->issue_time =3D ktime_get_real(); =20 /* send the request */ diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h index 01a35e113ab9..5531dd08061e 100644 --- a/include/net/af_rxrpc.h +++ b/include/net/af_rxrpc.h @@ -40,16 +40,17 @@ typedef void (*rxrpc_user_attach_call_t)(struct rxrpc_c= all *, unsigned long); void rxrpc_kernel_new_call_notification(struct socket *, rxrpc_notify_new_call_t, rxrpc_discard_new_call_t); -struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *, - struct sockaddr_rxrpc *, - struct key *, - unsigned long, - s64, - gfp_t, - rxrpc_notify_rx_t, - bool, - enum rxrpc_interruptibility, - unsigned int); +struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock, + struct sockaddr_rxrpc *srx, + struct key *key, + unsigned long user_call_ID, + s64 tx_total_len, + u32 hard_timeout, + gfp_t gfp, + rxrpc_notify_rx_t notify_rx, + bool upgrade, + enum rxrpc_interruptibility interruptibility, + unsigned int debug_id); int rxrpc_kernel_send_data(struct socket *, struct rxrpc_call *, struct msghdr *, size_t, rxrpc_notify_end_tx_t); diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c index c32b164206f9..31f738d65f1c 100644 --- a/net/rxrpc/af_rxrpc.c +++ b/net/rxrpc/af_rxrpc.c @@ -265,6 +265,7 @@ static int rxrpc_listen(struct socket *sock, int backlo= g) * @key: The security context to use (defaults to socket setting) * @user_call_ID: The ID to use * @tx_total_len: Total length of data to transmit during the call (or -1) + * @hard_timeout: The maximum lifespan of the call in sec * @gfp: The allocation constraints * @notify_rx: Where to send notifications instead of socket queue * @upgrade: Request service upgrade for call @@ -283,6 +284,7 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socke= t *sock, struct key *key, unsigned long user_call_ID, s64 tx_total_len, + u32 hard_timeout, gfp_t gfp, rxrpc_notify_rx_t notify_rx, bool upgrade, @@ -313,6 +315,7 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socke= t *sock, p.tx_total_len =3D tx_total_len; p.interruptibility =3D interruptibility; p.kernel =3D true; + p.timeouts.hard =3D hard_timeout; =20 memset(&cp, 0, sizeof(cp)); cp.local =3D rx->local; diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index 67b0a894162d..5d44dc08f66d 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -616,6 +616,7 @@ struct rxrpc_call { unsigned long expect_term_by; /* When we expect call termination by */ u32 next_rx_timo; /* Timeout for next Rx packet (jif) */ u32 next_req_timo; /* Timeout for next Rx request packet (jif) */ + u32 hard_timo; /* Maximum lifetime or 0 (jif) */ struct timer_list timer; /* Combined event timer */ struct work_struct destroyer; /* In-process-context destroyer */ rxrpc_notify_rx_t notify_rx; /* kernel service Rx notification function */ diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c index e9f1f49d18c2..fecbc73054bc 100644 --- a/net/rxrpc/call_object.c +++ b/net/rxrpc/call_object.c @@ -226,6 +226,13 @@ static struct rxrpc_call *rxrpc_alloc_client_call(stru= ct rxrpc_sock *rx, if (cp->exclusive) __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags); =20 + if (p->timeouts.normal) + call->next_rx_timo =3D min(msecs_to_jiffies(p->timeouts.normal), 1UL); + if (p->timeouts.idle) + call->next_req_timo =3D min(msecs_to_jiffies(p->timeouts.idle), 1UL); + if (p->timeouts.hard) + call->hard_timo =3D p->timeouts.hard * HZ; + ret =3D rxrpc_init_client_call_security(call); if (ret < 0) { rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret); @@ -257,7 +264,7 @@ void rxrpc_start_call_timer(struct rxrpc_call *call) call->keepalive_at =3D j; call->expect_rx_by =3D j; call->expect_req_by =3D j; - call->expect_term_by =3D j; + call->expect_term_by =3D j + call->hard_timo; call->timer.expires =3D now; } =20 diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c index c1b074c17b33..8e0b94714e84 100644 --- a/net/rxrpc/sendmsg.c +++ b/net/rxrpc/sendmsg.c @@ -651,6 +651,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msgh= dr *msg, size_t len) if (IS_ERR(call)) return PTR_ERR(call); /* ... and we have the call lock. */ + p.call.nr_timeouts =3D 0; ret =3D 0; if (rxrpc_call_is_complete(call)) goto out_put_unlock;