pvrdma: check return value from pvrdma_idx_ring_has_ routines

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>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
This commit is contained in:
Prasad J Pandit 2018-12-13 01:00:39 +05:30 committed by Marcel Apfelbaum
parent 7be3a21325
commit f1e2e38ee0

View File

@ -73,23 +73,16 @@ out:
void *pvrdma_ring_next_elem_read(PvrdmaRing *ring)
{
int e;
unsigned int idx = 0, offset;
/*
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)) {
e = pvrdma_idx_ring_has_data(ring->ring_state, ring->max_elems, &idx);
if (e <= 0) {
pr_dbg("No more data in ring\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 +98,20 @@ 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);