From: David Howells dhowells@redhat.com
[ Upstream commit db099c625b13a74d462521a46d98a8ce5b53af5d ]
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: <TASK> 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 marc.dionne@auristor.com Signed-off-by: David Howells dhowells@redhat.com cc: "David S. Miller" davem@davemloft.net cc: Eric Dumazet edumazet@google.com cc: Jakub Kicinski kuba@kernel.org cc: Paolo Abeni pabeni@redhat.com cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@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 432cb4b239614..81815724db6c9 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 */
-#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
typedef u64 afs_volid_t; typedef u64 afs_vnodeid_t; diff --git a/fs/afs/internal.h b/fs/afs/internal.h index ad8523d0d0386..68ae91d21b578 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 7817e2b860e5e..6862e3dde364b 100644 --- a/fs/afs/rxrpc.c +++ b/fs/afs/rxrpc.c @@ -334,7 +334,9 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) /* create a call */ rxcall = 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), @@ -349,10 +351,6 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp) }
call->rxcall = rxcall; - - if (call->max_lifespan) - rxrpc_kernel_set_max_life(call->net->socket, rxcall, - call->max_lifespan); call->issue_time = ktime_get_real();
/* send the request */ diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h index ba717eac0229a..73644bd42a3f9 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_call *, 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 102f5cbff91a3..a6f0d29f35ef9 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 backlog) * @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 socket *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 socket *sock, p.tx_total_len = tx_total_len; p.interruptibility = interruptibility; p.kernel = true; + p.timeouts.hard = hard_timeout;
memset(&cp, 0, sizeof(cp)); cp.local = rx->local; diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index 67b0a894162d7..5d44dc08f66d0 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 e9f1f49d18c2a..fecbc73054bc2 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(struct rxrpc_sock *rx, if (cp->exclusive) __set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
+ if (p->timeouts.normal) + call->next_rx_timo = min(msecs_to_jiffies(p->timeouts.normal), 1UL); + if (p->timeouts.idle) + call->next_req_timo = min(msecs_to_jiffies(p->timeouts.idle), 1UL); + if (p->timeouts.hard) + call->hard_timo = p->timeouts.hard * HZ; + ret = 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 = j; call->expect_rx_by = j; call->expect_req_by = j; - call->expect_term_by = j; + call->expect_term_by = j + call->hard_timo; call->timer.expires = now; }
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c index c1b074c17b33e..8e0b94714e849 100644 --- a/net/rxrpc/sendmsg.c +++ b/net/rxrpc/sendmsg.c @@ -651,6 +651,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len) if (IS_ERR(call)) return PTR_ERR(call); /* ... and we have the call lock. */ + p.call.nr_timeouts = 0; ret = 0; if (rxrpc_call_is_complete(call)) goto out_put_unlock;