| Message ID | 20130725170409.GB7026@elgon.mountain (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 7/25/2013 12:04 PM, Dan Carpenter wrote: > The "uresp.reserved" field isn't initialized. It's at the end, of the > struct here so we don't need to copy it to the user. > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > > diff --git a/drivers/infiniband/hw/cxgb3/iwch_provider.c b/drivers/infiniband/hw/cxgb3/iwch_provider.c > index e87f220..b8e26f2 100644 > --- a/drivers/infiniband/hw/cxgb3/iwch_provider.c > +++ b/drivers/infiniband/hw/cxgb3/iwch_provider.c > @@ -226,7 +226,7 @@ static struct ib_cq *iwch_create_cq(struct ib_device *ibdev, int entries, int ve > mm->len = PAGE_ALIGN(((1UL << uresp.size_log2) + 1) * > sizeof(struct t3_cqe)); > uresp.memsize = mm->len; > - resplen = sizeof uresp; > + resplen = sizeof uresp - sizeof uresp.reserved; > } > if (ib_copy_to_udata(udata, &uresp, resplen)) { > kfree(mm); How did you find this? What if, in the future, the iwch_create_cq_resp struct is changed and stuff added to the end? I'm not sure this optimization is worth it? -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jul 25, 2013 at 01:43:28PM -0500, Steve Wise wrote: > On 7/25/2013 12:04 PM, Dan Carpenter wrote: > >The "uresp.reserved" field isn't initialized. It's at the end, of the > >struct here so we don't need to copy it to the user. > > > >Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > > > >diff --git a/drivers/infiniband/hw/cxgb3/iwch_provider.c b/drivers/infiniband/hw/cxgb3/iwch_provider.c > >index e87f220..b8e26f2 100644 > >--- a/drivers/infiniband/hw/cxgb3/iwch_provider.c > >+++ b/drivers/infiniband/hw/cxgb3/iwch_provider.c > >@@ -226,7 +226,7 @@ static struct ib_cq *iwch_create_cq(struct ib_device *ibdev, int entries, int ve > > mm->len = PAGE_ALIGN(((1UL << uresp.size_log2) + 1) * > > sizeof(struct t3_cqe)); > > uresp.memsize = mm->len; > >- resplen = sizeof uresp; > >+ resplen = sizeof uresp - sizeof uresp.reserved; > > } > > if (ib_copy_to_udata(udata, &uresp, resplen)) { > > kfree(mm); > > How did you find this? This is some incoming Smatch stuff. > > What if, in the future, the iwch_create_cq_resp struct is changed > and stuff added to the end? I'm not sure this optimization is worth > it? Yeah. I'm not sure either. I wouldn't do it outside infiniband code because I was copying other code from there. I can redo this. regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/infiniband/hw/cxgb3/iwch_provider.c b/drivers/infiniband/hw/cxgb3/iwch_provider.c index e87f220..b8e26f2 100644 --- a/drivers/infiniband/hw/cxgb3/iwch_provider.c +++ b/drivers/infiniband/hw/cxgb3/iwch_provider.c @@ -226,7 +226,7 @@ static struct ib_cq *iwch_create_cq(struct ib_device *ibdev, int entries, int ve mm->len = PAGE_ALIGN(((1UL << uresp.size_log2) + 1) * sizeof(struct t3_cqe)); uresp.memsize = mm->len; - resplen = sizeof uresp; + resplen = sizeof uresp - sizeof uresp.reserved; } if (ib_copy_to_udata(udata, &uresp, resplen)) { kfree(mm);
The "uresp.reserved" field isn't initialized. It's at the end, of the struct here so we don't need to copy it to the user. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html