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From 67d9c2d11508b2523445cc5f65bdbb2c32e52688 Mon Sep 17 00:00:00 2001 |
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From: Sasha Levin <sashal@kernel.org> |
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Date: Tue, 1 Mar 2022 23:28:22 +0100 |
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Subject: sfc: extend the locking on mcdi->seqno |
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From: Niels Dossche <dossche.niels@gmail.com> |
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[ Upstream commit f1fb205efb0ccca55626fd4ef38570dd16b44719 ] |
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|
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seqno could be read as a stale value outside of the lock. The lock is |
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already acquired to protect the modification of seqno against a possible |
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race condition. Place the reading of this value also inside this locking |
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to protect it against a possible race condition. |
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|
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Signed-off-by: Niels Dossche <dossche.niels@gmail.com> |
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Acked-by: Martin Habets <habetsm.xilinx@gmail.com> |
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Signed-off-by: David S. Miller <davem@davemloft.net> |
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Signed-off-by: Sasha Levin <sashal@kernel.org> |
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--- |
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drivers/net/ethernet/sfc/mcdi.c | 2 +- |
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1 file changed, 1 insertion(+), 1 deletion(-) |
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|
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diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c |
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index be6bfd6b7ec7..50baf62b2cbc 100644 |
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--- a/drivers/net/ethernet/sfc/mcdi.c |
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+++ b/drivers/net/ethernet/sfc/mcdi.c |
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@@ -163,9 +163,9 @@ static void efx_mcdi_send_request(struct efx_nic *efx, unsigned cmd, |
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/* Serialise with efx_mcdi_ev_cpl() and efx_mcdi_ev_death() */ |
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spin_lock_bh(&mcdi->iface_lock); |
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++mcdi->seqno; |
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+ seqno = mcdi->seqno & SEQ_MASK; |
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spin_unlock_bh(&mcdi->iface_lock); |
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|
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- seqno = mcdi->seqno & SEQ_MASK; |
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xflags = 0; |
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if (mcdi->mode == MCDI_MODE_EVENTS) |
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xflags |= MCDI_HEADER_XFLAGS_EVREQ; |
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-- |
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2.34.1 |
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