On Mon, Aug 23, 2021 at 12:37 PM yangx.jy@xxxxxxxxxxx
<yangx.jy@xxxxxxxxxxx> wrote:
>
> On 2021/8/21 15:21, Zhu Yanjun wrote:
> > On Fri, Aug 20, 2021 at 6:44 PM Xiao Yang<yangx.jy@xxxxxxxxxxx> wrote:
> >> 1) New index member of struct rxe_queue is introduced but not zeroed
> >> so the initial value of index may be random.
> >> 2) Current index is not masked off to index_mask.
> >> In such case, producer_addr() and consumer_addr() will get an invalid
> >> address by the random index and then accessing the invalid address
> >> triggers the following panic:
> >> "BUG: unable to handle page fault for address: ffff9ae2c07a1414"
> >>
> >> Fix the issue by using kzalloc() to zero out index member.
> >>
> >> Fixes: 5bcf5a59c41e ("RDMA/rxe: Protext kernel index from user space")
> >> Signed-off-by: Xiao Yang<yangx.jy@xxxxxxxxxxx>
> >> ---
> >> drivers/infiniband/sw/rxe/rxe_queue.c | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/infiniband/sw/rxe/rxe_queue.c b/drivers/infiniband/sw/rxe/rxe_queue.c
> >> index 85b812586ed4..72d95398e604 100644
> >> --- a/drivers/infiniband/sw/rxe/rxe_queue.c
> >> +++ b/drivers/infiniband/sw/rxe/rxe_queue.c
> >> @@ -63,7 +63,7 @@ struct rxe_queue *rxe_queue_init(struct rxe_dev *rxe, int *num_elem,
> >> if (*num_elem< 0)
> >> goto err1;
> >>
> >> - q = kmalloc(sizeof(*q), GFP_KERNEL);
> >> + q = kzalloc(sizeof(*q), GFP_KERNEL);
> > Perhaps this is why I can not reproduce this problem in the local host.
> Hi Yanjun,
>
> I forgot to say that I reproduced the issue on my local vm.
Which OS are you using to reproduce this problem?
Zhu Yanjun
>
> Best Regards,
> Xiao Yang
> > Zhu Yanjun
> >
> >> if (!q)
> >> goto err1;
> >>
> >> --
> >> 2.25.1
> >>
> >>
> >>
