dmaengine: idxd: Fix possible Use-After-Free in irq_process_work_list

Use list_for_each_entry_safe() to allow iterating through the list and
deleting the entry in the iteration process. The descriptor is freed via
idxd_desc_complete() and there's a slight chance may cause issue for
the list iterator when the descriptor is reused by another thread
without it being deleted from the list.

Fixes: 16e19e11228b ("dmaengine: idxd: Fix list corruption in description completion")
Signed-off-by: Li RongQing <[email protected]>
Reviewed-by: Dave Jiang <[email protected]>
Reviewed-by: Fenghua Yu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

diff --git a/drivers/dma/idxd/irq.c b/drivers/dma/idxd/irq.c
index 8dc029c8655151a1a47d7849e6fae313c4130add..fc049c9c9892e66302929afd9b0f99b881feca92 100644 (file)
--- a/drivers/dma/idxd/irq.c
+++ b/drivers/dma/idxd/irq.c
@@ -611,11 +611,13 @@ static void irq_process_work_list(struct idxd_irq_entry *irq_entry)
 
        spin_unlock(&irq_entry->list_lock);
 
-       list_for_each_entry(desc, &flist, list) {
+       list_for_each_entry_safe(desc, n, &flist, list) {
                /*
                 * Check against the original status as ABORT is software defined
                 * and 0xff, which DSA_COMP_STATUS_MASK can mask out.
                 */
+               list_del(&desc->list);
+
                if (unlikely(desc->completion->status == IDXD_COMP_DESC_ABORT)) {
                        idxd_desc_complete(desc, IDXD_COMPLETE_ABORT, true);
                        continue;