From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 4.20 053/117] IB/hfi1: Incorrect sizing of sge for PIO will OOPs Date: Tue, 8 Jan 2019 14:25:21 -0500 Message-ID: <20190108192628.121270-53-sashal@kernel.org> References: <20190108192628.121270-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190108192628.121270-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Michael J. Ruhl" , Dennis Dalessandro , Jason Gunthorpe , Sasha Levin , linux-rdma@vger.kernel.org List-Id: linux-rdma@vger.kernel.org From: "Michael J. Ruhl" [ Upstream commit dbc2970caef74e8ff41923d302aa6fb5a4812d0e ] An incorrect sge sizing in the HFI PIO path will cause an OOPs similar to this: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] hfi1_verbs_send_pio+0x3d8/0x530 [hfi1] PGD 0 Oops: 0000 1 SMP Call Trace: ? hfi1_verbs_send_dma+0xad0/0xad0 [hfi1] hfi1_verbs_send+0xdf/0x250 [hfi1] ? make_rc_ack+0xa80/0xa80 [hfi1] hfi1_do_send+0x192/0x430 [hfi1] hfi1_do_send_from_rvt+0x10/0x20 [hfi1] rvt_post_send+0x369/0x820 [rdmavt] ib_uverbs_post_send+0x317/0x570 [ib_uverbs] ib_uverbs_write+0x26f/0x420 [ib_uverbs] ? security_file_permission+0x21/0xa0 vfs_write+0xbd/0x1e0 ? mntput+0x24/0x40 SyS_write+0x7f/0xe0 system_call_fastpath+0x16/0x1b Fix by adding the missing sizing check to correctly determine the sge length. Fixes: 7724105686e7 ("IB/hfi1: add driver files") Reviewed-by: Mike Marciniszyn Signed-off-by: Michael J. Ruhl Signed-off-by: Dennis Dalessandro Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/hw/hfi1/verbs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/infiniband/hw/hfi1/verbs.c b/drivers/infiniband/hw/hfi1/verbs.c index a365089a9305..b7257d7dd925 100644 --- a/drivers/infiniband/hw/hfi1/verbs.c +++ b/drivers/infiniband/hw/hfi1/verbs.c @@ -919,6 +919,8 @@ int hfi1_verbs_send_pio(struct rvt_qp *qp, struct hfi1_pkt_state *ps, if (slen > len) slen = len; + if (slen > ss->sge.sge_length) + slen = ss->sge.sge_length; rvt_update_sge(ss, slen, false); seg_pio_copy_mid(pbuf, addr, slen); len -= slen; -- 2.19.1