2014-04-10 00:28:08

by Devesh Sharma

[permalink] [raw]
Subject: [PATCH V2] NFS-RDMA: fix qp pointer validation checks

If the rdma_create_qp fails to create qp due to device firmware being in invalid state
xprtrdma still tries to destroy the non-existant qp and ends up in a NULL pointer reference
crash.
Adding proper checks for vaidating QP pointer avoids this to happen.

V0: Using IS_ERR() to check validity of qp pointer.
V1: Use of IS_ERR() will not be able to catch NULL QP pointers as rdma_create_qp() returnes NULL in case
ib_create_qp verb is failed. Therefore, changed from usage of IS_ERR to null pointer check.
V2: ib_post_send() should not abort after DECR_CQCOUNT() checking for NULL pointer was causing exit from functions
after decrementing CQCOUNT(). Fixed this in V2.

Signed-off-by: Devesh Sharma <[email protected]>
---
net/sunrpc/xprtrdma/verbs.c | 92 ++++++++++++++++++++++++++-----------------
1 files changed, 56 insertions(+), 36 deletions(-)

diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 9372656..9e56baf 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -831,10 +831,12 @@ rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
if (ep->rep_connected != 0) {
struct rpcrdma_xprt *xprt;
retry:
- rc = rpcrdma_ep_disconnect(ep, ia);
- if (rc && rc != -ENOTCONN)
- dprintk("RPC: %s: rpcrdma_ep_disconnect"
+ if (ia->ri_id->qp) {
+ rc = rpcrdma_ep_disconnect(ep, ia);
+ if (rc && rc != -ENOTCONN)
+ dprintk("RPC: %s: rpcrdma_ep_disconnect"
" status %i\n", __func__, rc);
+ }
rpcrdma_clean_cq(ep->rep_cq);

xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
@@ -859,7 +861,8 @@ retry:
goto out;
}
/* END TEMP */
- rdma_destroy_qp(ia->ri_id);
+ if (ia->ri_id->qp)
+ rdma_destroy_qp(ia->ri_id);
rdma_destroy_id(ia->ri_id);
ia->ri_id = id;
}
@@ -1555,22 +1558,30 @@ rpcrdma_register_frmr_external(struct rpcrdma_mr_seg *seg,
IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
IB_ACCESS_REMOTE_READ);
frmr_wr.wr.fast_reg.rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
- DECR_CQCOUNT(&r_xprt->rx_ep);

- rc = ib_post_send(ia->ri_id->qp, post_wr, &bad_wr);
+ if (!ia->ri_id->qp) {
+ DECR_CQCOUNT(&r_xprt->rx_ep);
+ rc = ib_post_send(ia->ri_id->qp, post_wr, &bad_wr);

- if (rc) {
- dprintk("RPC: %s: failed ib_post_send for register,"
- " status %i\n", __func__, rc);
- while (i--)
- rpcrdma_unmap_one(ia, --seg);
+ if (rc) {
+ dprintk("RPC: %s: failed ib_post_send for register,"
+ " status %i\n", __func__, rc);
+ goto out;
+ } else {
+ seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
+ seg1->mr_base = seg1->mr_dma + pageoff;
+ seg1->mr_nsegs = i;
+ seg1->mr_len = len;
+ }
} else {
- seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
- seg1->mr_base = seg1->mr_dma + pageoff;
- seg1->mr_nsegs = i;
- seg1->mr_len = len;
+ rc = -EINVAL;
+ goto out;
}
+
*nsegs = i;
+out:
+ while (i--)
+ rpcrdma_unmap_one(ia, --seg);
return rc;
}

@@ -1590,12 +1601,16 @@ rpcrdma_deregister_frmr_external(struct rpcrdma_mr_seg *seg,
invalidate_wr.opcode = IB_WR_LOCAL_INV;
invalidate_wr.send_flags = IB_SEND_SIGNALED;
invalidate_wr.ex.invalidate_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
- DECR_CQCOUNT(&r_xprt->rx_ep);

- rc = ib_post_send(ia->ri_id->qp, &invalidate_wr, &bad_wr);
- if (rc)
- dprintk("RPC: %s: failed ib_post_send for invalidate,"
- " status %i\n", __func__, rc);
+ if (ia->ri_id->qp) {
+ DECR_CQCOUNT(&r_xprt->rx_ep);
+ rc = ib_post_send(ia->ri_id->qp, &invalidate_wr, &bad_wr);
+ if (rc)
+ dprintk("RPC: %s: failed ib_post_send for invalidate,"
+ " status %i\n", __func__, rc);
+ } else
+ rc = -EINVAL;
+
return rc;
}

@@ -1916,17 +1931,19 @@ rpcrdma_ep_post(struct rpcrdma_ia *ia,
req->rl_send_iov[0].addr, req->rl_send_iov[0].length,
DMA_TO_DEVICE);

- if (DECR_CQCOUNT(ep) > 0)
- send_wr.send_flags = 0;
- else { /* Provider must take a send completion every now and then */
- INIT_CQCOUNT(ep);
- send_wr.send_flags = IB_SEND_SIGNALED;
- }
-
- rc = ib_post_send(ia->ri_id->qp, &send_wr, &send_wr_fail);
- if (rc)
- dprintk("RPC: %s: ib_post_send returned %i\n", __func__,
- rc);
+ if (ia->ri_id->qp) {
+ if (DECR_CQCOUNT(ep) > 0)
+ send_wr.send_flags = 0;
+ else { /* Provider must take a send completion every now and then */
+ INIT_CQCOUNT(ep);
+ send_wr.send_flags = IB_SEND_SIGNALED
+ }
+ rc = ib_post_send(ia->ri_id->qp, &send_wr, &send_wr_fail);
+ if (rc)
+ dprintk("RPC: %s: ib_post_send returned %i\n", __func__,
+ rc);
+ } else
+ rc = -EINVAL;
out:
return rc;
}
@@ -1950,11 +1967,14 @@ rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
ib_dma_sync_single_for_cpu(ia->ri_id->device,
rep->rr_iov.addr, rep->rr_iov.length, DMA_BIDIRECTIONAL);

- DECR_CQCOUNT(ep);
- rc = ib_post_recv(ia->ri_id->qp, &recv_wr, &recv_wr_fail);
+ if (ia->ri_id->qp) {
+ DECR_CQCOUNT(ep);
+ rc = ib_post_recv(ia->ri_id->qp, &recv_wr, &recv_wr_fail);
+ if (rc)
+ dprintk("RPC: %s: ib_post_recv returned %i\n", __func__,
+ rc);
+ } else
+ rc = -EINVAL;

- if (rc)
- dprintk("RPC: %s: ib_post_recv returned %i\n", __func__,
- rc);
return rc;
}
--
1.7.1



2014-04-10 00:35:23

by Chuck Lever

[permalink] [raw]
Subject: Re: [PATCH V2] NFS-RDMA: fix qp pointer validation checks

Hi Devesh-


On Apr 9, 2014, at 7:54 PM, Devesh Sharma <[email protected]> wrote:

> If the rdma_create_qp fails to create qp due to device firmware being in invalid state
> xprtrdma still tries to destroy the non-existant qp and ends up in a NULL pointer reference
> crash.
> Adding proper checks for vaidating QP pointer avoids this to happen.
>
> V0: Using IS_ERR() to check validity of qp pointer.
> V1: Use of IS_ERR() will not be able to catch NULL QP pointers as rdma_create_qp() returnes NULL in case
> ib_create_qp verb is failed. Therefore, changed from usage of IS_ERR to null pointer check.
> V2: ib_post_send() should not abort after DECR_CQCOUNT() checking for NULL pointer was causing exit from functions
> after decrementing CQCOUNT(). Fixed this in V2.
>
> Signed-off-by: Devesh Sharma <[email protected]>
> ---
> net/sunrpc/xprtrdma/verbs.c | 92 ++++++++++++++++++++++++++-----------------
> 1 files changed, 56 insertions(+), 36 deletions(-)
>
> diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
> index 9372656..9e56baf 100644
> --- a/net/sunrpc/xprtrdma/verbs.c
> +++ b/net/sunrpc/xprtrdma/verbs.c
> @@ -831,10 +831,12 @@ rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
> if (ep->rep_connected != 0) {
> struct rpcrdma_xprt *xprt;
> retry:
> - rc = rpcrdma_ep_disconnect(ep, ia);
> - if (rc && rc != -ENOTCONN)
> - dprintk("RPC: %s: rpcrdma_ep_disconnect"
> + if (ia->ri_id->qp) {
> + rc = rpcrdma_ep_disconnect(ep, ia);
> + if (rc && rc != -ENOTCONN)
> + dprintk("RPC: %s: rpcrdma_ep_disconnect"
> " status %i\n", __func__, rc);
> + }
> rpcrdma_clean_cq(ep->rep_cq);
>
> xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
> @@ -859,7 +861,8 @@ retry:
> goto out;
> }
> /* END TEMP */
> - rdma_destroy_qp(ia->ri_id);
> + if (ia->ri_id->qp)
> + rdma_destroy_qp(ia->ri_id);
> rdma_destroy_id(ia->ri_id);
> ia->ri_id = id;
> }

Does your set up still panic if rpcrdma_ep_connect() is fixed as above, but the rest of these hunks are left unapplied?


> @@ -1555,22 +1558,30 @@ rpcrdma_register_frmr_external(struct rpcrdma_mr_seg *seg,
> IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
> IB_ACCESS_REMOTE_READ);
> frmr_wr.wr.fast_reg.rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
> - DECR_CQCOUNT(&r_xprt->rx_ep);
>
> - rc = ib_post_send(ia->ri_id->qp, post_wr, &bad_wr);
> + if (!ia->ri_is->qp) {

You mean ?if (ia->ri_id->qp) {?

> + DECR_CQCOUNT(&r_xprt->rx_ep);
> + rc = ib_post_send(ia->ri_id->qp, post_wr, &bad_wr);
>
> - if (rc) {
> - dprintk("RPC: %s: failed ib_post_send for register,"
> - " status %i\n", __func__, rc);
> - while (i--)
> - rpcrdma_unmap_one(ia, --seg);
> + if (rc) {
> + dprintk("RPC: %s: failed ib_post_send for register,"
> + " status %i\n", __func__, rc);
> + goto out;
> + } else {
> + seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
> + seg1->mr_base = seg1->mr_dma + pageoff;
> + seg1->mr_nsegs = i;
> + seg1->mr_len = len;
> + }
> } else {
> - seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
> - seg1->mr_base = seg1->mr_dma + pageoff;
> - seg1->mr_nsegs = i;
> - seg1->mr_len = len;
> + rc = -EINVAL;
> + goto out;
> }
> +
> *nsegs = i;
> +out:
> + while (i--)
> + rpcrdma_unmap_one(ia, --seg);
> return rc;
> }
>
> @@ -1590,12 +1601,16 @@ rpcrdma_deregister_frmr_external(struct rpcrdma_mr_seg *seg,
> invalidate_wr.opcode = IB_WR_LOCAL_INV;
> invalidate_wr.send_flags = IB_SEND_SIGNALED;
> invalidate_wr.ex.invalidate_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey;
> - DECR_CQCOUNT(&r_xprt->rx_ep);
>
> - rc = ib_post_send(ia->ri_id->qp, &invalidate_wr, &bad_wr);
> - if (rc)
> - dprintk("RPC: %s: failed ib_post_send for invalidate,"
> - " status %i\n", __func__, rc);
> + if (ia->ri_id->qp) {
> + DECR_CQCOUNT(&r_xprt->rx_ep);
> + rc = ib_post_send(ia->ri_id->qp, &invalidate_wr, &bad_wr);
> + if (rc)
> + dprintk("RPC: %s: failed ib_post_send for invalidate,"
> + " status %i\n", __func__, rc);
> + } else
> + rc = -EINVAL;
> +
> return rc;
> }
>
> @@ -1916,17 +1931,19 @@ rpcrdma_ep_post(struct rpcrdma_ia *ia,
> req->rl_send_iov[0].addr, req->rl_send_iov[0].length,
> DMA_TO_DEVICE);
>
> - if (DECR_CQCOUNT(ep) > 0)
> - send_wr.send_flags = 0;
> - else { /* Provider must take a send completion every now and then */
> - INIT_CQCOUNT(ep);
> - send_wr.send_flags = IB_SEND_SIGNALED;
> - }
> -
> - rc = ib_post_send(ia->ri_id->qp, &send_wr, &send_wr_fail);
> - if (rc)
> - dprintk("RPC: %s: ib_post_send returned %i\n", __func__,
> - rc);
> + if (ia->ri_id->qp) {
> + if (DECR_CQCOUNT(ep) > 0)
> + send_wr.send_flags = 0;
> + else { /* Provider must take a send completion every now and then */
> + INIT_CQCOUNT(ep);
> + send_wr.send_flags = IB_SEND_SIGNALED
> + }
> + rc = ib_post_send(ia->ri_id->qp, &send_wr, &send_wr_fail);
> + if (rc)
> + dprintk("RPC: %s: ib_post_send returned %i\n", __func__,
> + rc);
> + } else
> + rc = -EINVAL;
> out:
> return rc;
> }
> @@ -1950,11 +1967,14 @@ rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
> ib_dma_sync_single_for_cpu(ia->ri_id->device,
> rep->rr_iov.addr, rep->rr_iov.length, DMA_BIDIRECTIONAL);
>
> - DECR_CQCOUNT(ep);
> - rc = ib_post_recv(ia->ri_id->qp, &recv_wr, &recv_wr_fail);
> + if (ia->ri_id->qp) {
> + DECR_CQCOUNT(ep);
> + rc = ib_post_recv(ia->ri_id->qp, &recv_wr, &recv_wr_fail);
> + if (rc)
> + dprintk("RPC: %s: ib_post_recv returned %i\n", __func__,
> + rc);
> + } else
> + rc = -EINVAL;
>
> - if (rc)
> - dprintk("RPC: %s: ib_post_recv returned %i\n", __func__,
> - rc);
> return rc;
> }
> --
> 1.7.1
>
> --
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--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com




2014-04-10 07:54:36

by Or Gerlitz

[permalink] [raw]
Subject: Re: [PATCH V2] NFS-RDMA: fix qp pointer validation checks

On 10/04/2014 02:56, Devesh Sharma wrote:
> If the rdma_create_qp fails to create qp due to device firmware being in invalid state
> xprtrdma still tries to destroy the non-existant qp and ends up in a NULL pointer reference
> crash.
> Adding proper checks for vaidating QP pointer avoids this to happen.
>
> V0: Using IS_ERR() to check validity of qp pointer.
> V1: Use of IS_ERR() will not be able to catch NULL QP pointers as rdma_create_qp() returnes NULL in case
> ib_create_qp verb is failed. Therefore, changed from usage of IS_ERR to null pointer check.
> V2: ib_post_send() should not abort after DECR_CQCOUNT() checking for NULL pointer was causing exit from functions
> after decrementing CQCOUNT(). Fixed this in V2.
>
> Signed-off-by: Devesh Sharma<[email protected]>
> ---
> net/sunrpc/xprtrdma/verbs.c | 92 ++++++++++++++++++++++++++-----------------
> 1 files changed, 56 insertions(+), 36 deletions(-)
The V0/V1/V2/etc history should be below the "---" such that it's
stripped out by git am when the maintain picks the patch