The "cplen" result used by the memcpy() into struct rvt_swqe "wqe" may
be sized to 80 for struct rvt_ud_wr (which is member "ud_wr", not "wr"
which is only 40 bytes in size). Change the destination union member so
the compiler can use the correct bounds check.
struct rvt_swqe {
union {
struct ib_send_wr wr; /* don't use wr.sg_list */
struct rvt_ud_wr ud_wr;
...
};
...
};
Silences false positive memcpy() run-time warning:
memcpy: detected field-spanning write (size 80) of single field "&wqe->wr" at drivers/infiniband/sw/rdmavt/qp.c:2043 (size 40)
Reported-by: Zhang Yi <[email protected]>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216561
Cc: Dennis Dalessandro <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Leon Romanovsky <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/infiniband/sw/rdmavt/qp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c
index 3acab569fbb9..3f707e1fa517 100644
--- a/drivers/infiniband/sw/rdmavt/qp.c
+++ b/drivers/infiniband/sw/rdmavt/qp.c
@@ -2040,7 +2040,7 @@ static int rvt_post_one_wr(struct rvt_qp *qp,
wqe = rvt_get_swqe_ptr(qp, qp->s_head);
/* cplen has length from above */
- memcpy(&wqe->wr, wr, cplen);
+ memcpy(&wqe->ud_wr, wr, cplen);
wqe->length = 0;
j = 0;
--
2.34.1
On 2/18/23 1:57 PM, Kees Cook wrote:
> The "cplen" result used by the memcpy() into struct rvt_swqe "wqe" may
> be sized to 80 for struct rvt_ud_wr (which is member "ud_wr", not "wr"
> which is only 40 bytes in size). Change the destination union member so
> the compiler can use the correct bounds check.
>
> struct rvt_swqe {
> union {
> struct ib_send_wr wr; /* don't use wr.sg_list */
> struct rvt_ud_wr ud_wr;
> ...
> };
> ...
> };
>
> Silences false positive memcpy() run-time warning:
>
> memcpy: detected field-spanning write (size 80) of single field "&wqe->wr" at drivers/infiniband/sw/rdmavt/qp.c:2043 (size 40)
>
> Reported-by: Zhang Yi <[email protected]>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216561
> Cc: Dennis Dalessandro <[email protected]>
> Cc: Jason Gunthorpe <[email protected]>
> Cc: Leon Romanovsky <[email protected]>
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> ---
> drivers/infiniband/sw/rdmavt/qp.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c
> index 3acab569fbb9..3f707e1fa517 100644
> --- a/drivers/infiniband/sw/rdmavt/qp.c
> +++ b/drivers/infiniband/sw/rdmavt/qp.c
> @@ -2040,7 +2040,7 @@ static int rvt_post_one_wr(struct rvt_qp *qp,
> wqe = rvt_get_swqe_ptr(qp, qp->s_head);
>
> /* cplen has length from above */
> - memcpy(&wqe->wr, wr, cplen);
> + memcpy(&wqe->ud_wr, wr, cplen);
>
> wqe->length = 0;
> j = 0;
Thanks for the patch. We've been debating this issue internally since last week.
The problem I have is this makes it look like everything is a "UD" req when it
could be a different QP type. Maybe we just need a comment explaining.
-Denny
On 2/21/23 8:00 AM, Dennis Dalessandro wrote:
> On 2/18/23 1:57 PM, Kees Cook wrote:
>> The "cplen" result used by the memcpy() into struct rvt_swqe "wqe" may
>> be sized to 80 for struct rvt_ud_wr (which is member "ud_wr", not "wr"
>> which is only 40 bytes in size). Change the destination union member so
>> the compiler can use the correct bounds check.
>>
>> struct rvt_swqe {
>> union {
>> struct ib_send_wr wr; /* don't use wr.sg_list */
>> struct rvt_ud_wr ud_wr;
>> ...
>> };
>> ...
>> };
>>
>> Silences false positive memcpy() run-time warning:
>>
>> memcpy: detected field-spanning write (size 80) of single field "&wqe->wr" at drivers/infiniband/sw/rdmavt/qp.c:2043 (size 40)
>>
>> Reported-by: Zhang Yi <[email protected]>
>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216561
>> Cc: Dennis Dalessandro <[email protected]>
>> Cc: Jason Gunthorpe <[email protected]>
>> Cc: Leon Romanovsky <[email protected]>
>> Cc: [email protected]
>> Signed-off-by: Kees Cook <[email protected]>
>> ---
>> drivers/infiniband/sw/rdmavt/qp.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c
>> index 3acab569fbb9..3f707e1fa517 100644
>> --- a/drivers/infiniband/sw/rdmavt/qp.c
>> +++ b/drivers/infiniband/sw/rdmavt/qp.c
>> @@ -2040,7 +2040,7 @@ static int rvt_post_one_wr(struct rvt_qp *qp,
>> wqe = rvt_get_swqe_ptr(qp, qp->s_head);
>>
>> /* cplen has length from above */
>> - memcpy(&wqe->wr, wr, cplen);
>> + memcpy(&wqe->ud_wr, wr, cplen);
>>
>> wqe->length = 0;
>> j = 0;
>
> Thanks for the patch. We've been debating this issue internally since last week.
> The problem I have is this makes it look like everything is a "UD" req when it
> could be a different QP type. Maybe we just need a comment explaining.
For what it's worth I did test this patch. If you could add the comment that'd
be great. If not I can touch it up later.
Reviewed-by: Dennis Dalessandro <[email protected]>
On Sat, 18 Feb 2023 10:57:05 -0800, Kees Cook wrote:
> The "cplen" result used by the memcpy() into struct rvt_swqe "wqe" may
> be sized to 80 for struct rvt_ud_wr (which is member "ud_wr", not "wr"
> which is only 40 bytes in size). Change the destination union member so
> the compiler can use the correct bounds check.
>
> struct rvt_swqe {
> union {
> struct ib_send_wr wr; /* don't use wr.sg_list */
> struct rvt_ud_wr ud_wr;
> ...
> };
> ...
> };
>
> [...]
Applied, thanks!
[1/1] IB/rdmavt: Fix target union member for rvt_post_one_wr()
https://git.kernel.org/rdma/rdma/c/f2f6e1661d38fb
Best regards,
--
Leon Romanovsky <[email protected]>