[PATCH] infiniband: ulp: srpt: Use flex array destination for memcpy()

[PATCH] infiniband: ulp: srpt: Use flex array destination for memcpy()

[Hangyu Hua]

In preparation for FORTIFY_SOURCE performing run-time destination buffer
bounds checking for memcpy(), specify the destination output buffer
explicitly, instead of asking memcpy() to write past the end of what looked
like a fixed-size object.

Notice that srp_rsp[] is a pointer to a structure that contains
flexible-array member data[]:

struct srp_rsp {
	...
	__be32	sense_data_len;
	__be32	resp_data_len;
	u8	data[];
};

link: https://github.com/KSPP/linux/issues/201
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---
 drivers/infiniband/ulp/srpt/ib_srpt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 21cbe30d526f..8c29e14150d3 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -1421,7 +1421,7 @@ static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,
 
 		srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;
 		srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);
-		memcpy(srp_rsp + 1, sense_data, sense_data_len);
+		memcpy(srp_rsp->data, sense_data, sense_data_len);
 	}
 
 	return sizeof(*srp_rsp) + sense_data_len;
-- 
2.34.1

Re: [PATCH] infiniband: ulp: srpt: Use flex array destination for memcpy()

[Gustavo A. R. Silva]

On Fri, Sep 09, 2022 at 10:29:43AM +0800, Hangyu Hua wrote:
> In preparation for FORTIFY_SOURCE performing run-time destination buffer
> bounds checking for memcpy(), specify the destination output buffer
> explicitly, instead of asking memcpy() to write past the end of what looked
> like a fixed-size object.
> 
> Notice that srp_rsp[] is a pointer to a structure that contains
> flexible-array member data[]:
> 
> struct srp_rsp {
> 	...
> 	__be32	sense_data_len;
> 	__be32	resp_data_len;
> 	u8	data[];
> };
> 
> link: https://github.com/KSPP/linux/issues/201
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks
--
Gustavo

> ---
>  drivers/infiniband/ulp/srpt/ib_srpt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
> index 21cbe30d526f..8c29e14150d3 100644
> --- a/drivers/infiniband/ulp/srpt/ib_srpt.c
> +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
> @@ -1421,7 +1421,7 @@ static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,
>  
>  		srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;
>  		srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);
> -		memcpy(srp_rsp + 1, sense_data, sense_data_len);
> +		memcpy(srp_rsp->data, sense_data, sense_data_len);
>  	}
>  
>  	return sizeof(*srp_rsp) + sense_data_len;
> -- 
> 2.34.1
> 

Re: [PATCH] infiniband: ulp: srpt: Use flex array destination for memcpy()

[Bart Van Assche]

On 9/8/22 19:29, Hangyu Hua wrote:
> In preparation for FORTIFY_SOURCE performing run-time destination buffer
> bounds checking for memcpy(), specify the destination output buffer
> explicitly, instead of asking memcpy() to write past the end of what looked
> like a fixed-size object.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH] infiniband: ulp: srpt: Use flex array destination for memcpy()

[Leon Romanovsky]

On Fri, 9 Sep 2022 10:29:43 +0800, Hangyu Hua wrote:
> In preparation for FORTIFY_SOURCE performing run-time destination buffer
> bounds checking for memcpy(), specify the destination output buffer
> explicitly, instead of asking memcpy() to write past the end of what looked
> like a fixed-size object.
> 
> Notice that srp_rsp[] is a pointer to a structure that contains
> flexible-array member data[]:
> 
> [...]

Applied, thanks!

[1/1] infiniband: ulp: srpt: Use flex array destination for memcpy()
      https://git.kernel.org/rdma/rdma/c/4b46a6079d2f8a

Best regards,
-- 
Leon Romanovsky <leon@kernel.org>