| Message ID | 20181212114726.24060-6-ppandit@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | rdma: various issues in rdma/pvrdma backend | expand |
On Wed, Dec 12, 2018 at 05:17:25PM +0530, P J P wrote: > From: Prasad J Pandit <pjp@fedoraproject.org> > > pvrdma_idx_ring_has_[data/space] routines also return invalid > index PVRDMA_INVALID_IDX[=-1], if ring has no data/space. Check > return value from these routines to avoid plausible infinite loops. > > Reported-by: Li Qiang <liq3ea@163.com> > Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> > --- > hw/rdma/vmw/pvrdma_dev_ring.c | 37 +++++++++++++++++------------------ > 1 file changed, 18 insertions(+), 19 deletions(-) > > Update v1: receive error code in idx variable, remove comments > -> https://lists.gnu.org/archive/html/qemu-devel/2018-12/msg02342.html > > diff --git a/hw/rdma/vmw/pvrdma_dev_ring.c b/hw/rdma/vmw/pvrdma_dev_ring.c > index 01247fc041..2dccac8442 100644 > --- a/hw/rdma/vmw/pvrdma_dev_ring.c > +++ b/hw/rdma/vmw/pvrdma_dev_ring.c > @@ -73,23 +73,22 @@ out: > > void *pvrdma_ring_next_elem_read(PvrdmaRing *ring) > { > - unsigned int idx = 0, offset; > + int idx; > + unsigned int offset, head; > > - /* > - pr_dbg("%s: t=%d, h=%d\n", ring->name, ring->ring_state->prod_tail, > - ring->ring_state->cons_head); > - */ > - > - if (!pvrdma_idx_ring_has_data(ring->ring_state, ring->max_elems, &idx)) { > + idx = pvrdma_idx_ring_has_data(ring->ring_state, ring->max_elems, &head); > + if (idx <= 0) { > pr_dbg("No more data in ring\n"); > return NULL; > } > > + idx = pvrdma_idx(&ring->ring_state->cons_head, ring->max_elems); > + if (idx < 0 || head != idx) { > + pr_dbg("invalid idx\n"); > + return NULL; > + } > + Sorry, i mislead you here, idx was already populated by pvrdma_idx_ring_has_data so call to pvrdma_idx just to retrieve the index is waste. Please revert back to using another variable to check the return value from pvrdma_idx_ring_has_data and drop this call to pvrdma_idx. > offset = idx * ring->elem_sz; > - /* > - pr_dbg("idx=%d\n", idx); > - pr_dbg("offset=%d\n", offset); > - */ > return ring->pages[offset / TARGET_PAGE_SIZE] + (offset % TARGET_PAGE_SIZE); > } > > @@ -105,20 +104,20 @@ void pvrdma_ring_read_inc(PvrdmaRing *ring) > > void *pvrdma_ring_next_elem_write(PvrdmaRing *ring) > { > - unsigned int idx, offset, tail; > + int idx; > + unsigned int offset, tail; > > - /* > - pr_dbg("%s: t=%d, h=%d\n", ring->name, ring->ring_state->prod_tail, > - ring->ring_state->cons_head); > - */ > - > - if (!pvrdma_idx_ring_has_space(ring->ring_state, ring->max_elems, &tail)) { > + idx = pvrdma_idx_ring_has_space(ring->ring_state, ring->max_elems, &tail); > + if (idx <= 0) { > pr_dbg("CQ is full\n"); > return NULL; > } > > idx = pvrdma_idx(&ring->ring_state->prod_tail, ring->max_elems); > - /* TODO: tail == idx */ > + if (idx < 0 || tail != idx) { > + pr_dbg("invalid idx\n"); > + return NULL; > + } > > offset = idx * ring->elem_sz; > return ring->pages[offset / TARGET_PAGE_SIZE] + (offset % TARGET_PAGE_SIZE); > -- > 2.19.2 >
diff --git a/hw/rdma/vmw/pvrdma_dev_ring.c b/hw/rdma/vmw/pvrdma_dev_ring.c index 01247fc041..2dccac8442 100644 --- a/hw/rdma/vmw/pvrdma_dev_ring.c +++ b/hw/rdma/vmw/pvrdma_dev_ring.c @@ -73,23 +73,22 @@ out: void *pvrdma_ring_next_elem_read(PvrdmaRing *ring) { - unsigned int idx = 0, offset; + int idx; + unsigned int offset, head; - /* - pr_dbg("%s: t=%d, h=%d\n", ring->name, ring->ring_state->prod_tail, - ring->ring_state->cons_head); - */ - - if (!pvrdma_idx_ring_has_data(ring->ring_state, ring->max_elems, &idx)) { + idx = pvrdma_idx_ring_has_data(ring->ring_state, ring->max_elems, &head); + if (idx <= 0) { pr_dbg("No more data in ring\n"); return NULL; } + idx = pvrdma_idx(&ring->ring_state->cons_head, ring->max_elems); + if (idx < 0 || head != idx) { + pr_dbg("invalid idx\n"); + return NULL; + } + offset = idx * ring->elem_sz; - /* - pr_dbg("idx=%d\n", idx); - pr_dbg("offset=%d\n", offset); - */ return ring->pages[offset / TARGET_PAGE_SIZE] + (offset % TARGET_PAGE_SIZE); } @@ -105,20 +104,20 @@ void pvrdma_ring_read_inc(PvrdmaRing *ring) void *pvrdma_ring_next_elem_write(PvrdmaRing *ring) { - unsigned int idx, offset, tail; + int idx; + unsigned int offset, tail; - /* - pr_dbg("%s: t=%d, h=%d\n", ring->name, ring->ring_state->prod_tail, - ring->ring_state->cons_head); - */ - - if (!pvrdma_idx_ring_has_space(ring->ring_state, ring->max_elems, &tail)) { + idx = pvrdma_idx_ring_has_space(ring->ring_state, ring->max_elems, &tail); + if (idx <= 0) { pr_dbg("CQ is full\n"); return NULL; } idx = pvrdma_idx(&ring->ring_state->prod_tail, ring->max_elems); - /* TODO: tail == idx */ + if (idx < 0 || tail != idx) { + pr_dbg("invalid idx\n"); + return NULL; + } offset = idx * ring->elem_sz; return ring->pages[offset / TARGET_PAGE_SIZE] + (offset % TARGET_PAGE_SIZE);