| Message ID | 20201012165229.59257-1-alex.dewar90@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | RDMA/rxe: Fix possible NULL pointer dereference | expand |
On Wed, Oct 14, 2020 at 8:34 AM Yanjun Zhu <yanjunz@nvidia.com> wrote: > > > > -----Original Message----- > From: Alex Dewar <alex.dewar90@gmail.com> > Sent: Tuesday, October 13, 2020 12:53 AM > Cc: Alex Dewar <alex.dewar90@gmail.com>; Yanjun Zhu <yanjunz@nvidia.com>; Doug Ledford <dledford@redhat.com>; Jason Gunthorpe <jgg@ziepe.ca>; Bob Pearson <rpearsonhpe@gmail.com>; linux-rdma@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: [PATCH] RDMA/rxe: Fix possible NULL pointer dereference > > skb_clone() is called without checking if the returned pointer is NULL before it is dereferenced. Fix by adding an additional error check. > > Fixes: e7ec96fc7932 ("RDMA/rxe: Fix skb lifetime in rxe_rcv_mcast_pkt()") > Addresses-Coverity-ID: 1497804: Null pointer dereferences (NULL_RETURNS) > Signed-off-by: Alex Dewar <alex.dewar90@gmail.com> Thanks a lot. Zhu Yanjun > --- > drivers/infiniband/sw/rxe/rxe_recv.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c > index 11f3daf20768..a65936e12f89 100644 > --- a/drivers/infiniband/sw/rxe/rxe_recv.c > +++ b/drivers/infiniband/sw/rxe/rxe_recv.c > @@ -266,10 +266,13 @@ static void rxe_rcv_mcast_pkt(struct rxe_dev *rxe, struct sk_buff *skb) > /* for all but the last qp create a new clone of the > * skb and pass to the qp. > */ > - if (mce->qp_list.next != &mcg->qp_list) > + if (mce->qp_list.next != &mcg->qp_list) { > per_qp_skb = skb_clone(skb, GFP_ATOMIC); > - else > + if (!per_qp_skb) > + goto err2; > + } else { > per_qp_skb = skb; > + } > > per_qp_pkt = SKB_TO_PKT(per_qp_skb); > per_qp_pkt->qp = qp; > @@ -283,6 +286,10 @@ static void rxe_rcv_mcast_pkt(struct rxe_dev *rxe, struct sk_buff *skb) > > return; > > +err2: > + spin_unlock_bh(&mcg->mcg_lock); > + rxe_drop_ref(mcg); /* drop ref from rxe_pool_get_key. */ > + > err1: > kfree_skb(skb); > } > -- > 2.28.0 >
On Mon, Oct 12, 2020 at 05:52:30PM +0100, Alex Dewar wrote: > skb_clone() is called without checking if the returned pointer is NULL > before it is dereferenced. Fix by adding an additional error check. > > Fixes: e7ec96fc7932 ("RDMA/rxe: Fix skb lifetime in rxe_rcv_mcast_pkt()") > Addresses-Coverity-ID: 1497804: Null pointer dereferences (NULL_RETURNS) > Signed-off-by: Alex Dewar <alex.dewar90@gmail.com> > --- > drivers/infiniband/sw/rxe/rxe_recv.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) I took Bob's version of this since it is a little bit simpler Thanks, Jason
diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c index 11f3daf20768..a65936e12f89 100644 --- a/drivers/infiniband/sw/rxe/rxe_recv.c +++ b/drivers/infiniband/sw/rxe/rxe_recv.c @@ -266,10 +266,13 @@ static void rxe_rcv_mcast_pkt(struct rxe_dev *rxe, struct sk_buff *skb) /* for all but the last qp create a new clone of the * skb and pass to the qp. */ - if (mce->qp_list.next != &mcg->qp_list) + if (mce->qp_list.next != &mcg->qp_list) { per_qp_skb = skb_clone(skb, GFP_ATOMIC); - else + if (!per_qp_skb) + goto err2; + } else { per_qp_skb = skb; + } per_qp_pkt = SKB_TO_PKT(per_qp_skb); per_qp_pkt->qp = qp; @@ -283,6 +286,10 @@ static void rxe_rcv_mcast_pkt(struct rxe_dev *rxe, struct sk_buff *skb) return; +err2: + spin_unlock_bh(&mcg->mcg_lock); + rxe_drop_ref(mcg); /* drop ref from rxe_pool_get_key. */ + err1: kfree_skb(skb); }
skb_clone() is called without checking if the returned pointer is NULL before it is dereferenced. Fix by adding an additional error check. Fixes: e7ec96fc7932 ("RDMA/rxe: Fix skb lifetime in rxe_rcv_mcast_pkt()") Addresses-Coverity-ID: 1497804: Null pointer dereferences (NULL_RETURNS) Signed-off-by: Alex Dewar <alex.dewar90@gmail.com> --- drivers/infiniband/sw/rxe/rxe_recv.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)