Re: Re: [PATCH] RDMA/siw: Fix missing check in siw_get_hdr
From: dinghao . liu
Date: Fri Feb 26 2021 - 07:33:57 EST
"Bernard Metzler" <BMT@xxxxxxxxxxxxxx>写道：
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-----"Dinghao Liu" <dinghao.liu@xxxxxxxxxx> wrote: -----
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>To: dinghao.liu@xxxxxxxxxx, kjlu@xxxxxxx
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>From: "Dinghao Liu" <dinghao.liu@xxxxxxxxxx>
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>Date: 02/26/2021 08:56AM
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>Cc: "Bernard Metzler" <bmt@xxxxxxxxxxxxxx>, "Doug Ledford"
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><dledford@xxxxxxxxxx>, "Jason Gunthorpe" <jgg@xxxxxxxx>,
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>linux-rdma@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
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>Subject: [EXTERNAL] [PATCH] RDMA/siw: Fix missing check in
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>siw_get_hdr
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>
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>We should also check the range of opcode after calling
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>__rdmap_get_opcode() in the else branch to prevent potential
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>overflow.
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Hi Dinghao,
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No this is not needed. We always first read the minimum
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header information (MPA len, DDP flags, RDMAP opcode,
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STag, target offset). Only if we have received that
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into local buffer, we check for the opcode this one time.
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Now the opcode determines the remaining length of the
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variably sized part of the header to be received.
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We do not have to check the opcode again, since we
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already received and checked it.
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It's clear to me, thanks!
Regards,
Dinghao