> -----Original Message----- > From: linux-rdma-owner@xxxxxxxxxxxxxxx [mailto:linux-rdma- > owner@xxxxxxxxxxxxxxx] On Behalf Of Dan Carpenter > Sent: Tuesday, January 9, 2018 3:04 PM > To: Marciniszyn, Mike <mike.marciniszyn@xxxxxxxxx> > Cc: Dalessandro, Dennis <dennis.dalessandro@xxxxxxxxx>; Doug Ledford > <dledford@xxxxxxxxxx>; Jason Gunthorpe <jgg@xxxxxxxx>; linux- > rdma@xxxxxxxxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx > Subject: [PATCH v2] IB/hfi1: Prevent a NULL dereference > > In the original code, we set "fd->uctxt" to NULL and then dereference it > which will cause an Oops. > > Fixes: f2a3bc00a03c ("IB/hfi1: Protect context array set/clear with spinlock") > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > --- > v2: In v1, I accidentally moved the __clear_bit() out from under the > spin_lock(). Thanks for the review, Michael! > > diff --git a/drivers/infiniband/hw/hfi1/file_ops.c > b/drivers/infiniband/hw/hfi1/file_ops.c > index 82086241aac3..bd6f03cc5ee0 100644 > --- a/drivers/infiniband/hw/hfi1/file_ops.c > +++ b/drivers/infiniband/hw/hfi1/file_ops.c > @@ -763,11 +763,11 @@ static int complete_subctxt(struct hfi1_filedata *fd) > } > > if (ret) { > - hfi1_rcd_put(fd->uctxt); > - fd->uctxt = NULL; > spin_lock_irqsave(&fd->dd->uctxt_lock, flags); > __clear_bit(fd->subctxt, fd->uctxt->in_use_ctxts); > spin_unlock_irqrestore(&fd->dd->uctxt_lock, flags); > + hfi1_rcd_put(fd->uctxt); > + fd->uctxt = NULL; > } > > return ret; > -- Cc: <stable@xxxxxxxxxxxxxxx> # 4.14.x Reviewed-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx> Looks good. Adding tag for stable too. Thanks, Mike > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
