From: Niels Dossche dossche.niels@gmail.com
[ Upstream commit f1fb205efb0ccca55626fd4ef38570dd16b44719 ]
seqno could be read as a stale value outside of the lock. The lock is already acquired to protect the modification of seqno against a possible race condition. Place the reading of this value also inside this locking to protect it against a possible race condition.
Signed-off-by: Niels Dossche dossche.niels@gmail.com Acked-by: Martin Habets habetsm.xilinx@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/sfc/mcdi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c index 2713300343c7..ec551def5835 100644 --- a/drivers/net/ethernet/sfc/mcdi.c +++ b/drivers/net/ethernet/sfc/mcdi.c @@ -163,9 +163,9 @@ static void efx_mcdi_send_request(struct efx_nic *efx, unsigned cmd, /* Serialise with efx_mcdi_ev_cpl() and efx_mcdi_ev_death() */ spin_lock_bh(&mcdi->iface_lock); ++mcdi->seqno; + seqno = mcdi->seqno & SEQ_MASK; spin_unlock_bh(&mcdi->iface_lock);
- seqno = mcdi->seqno & SEQ_MASK; xflags = 0; if (mcdi->mode == MCDI_MODE_EVENTS) xflags |= MCDI_HEADER_XFLAGS_EVREQ;