Commit 57ddfecc authored by Daniel Jordan's avatar Daniel Jordan Committed by Herbert Xu
Browse files

padata: Fix list iterator in padata_do_serial() 



list_for_each_entry_reverse() assumes that the iterated list is nonempty
and that every list_head is embedded in the same type, but its use in
padata_do_serial() breaks both rules.

This doesn't cause any issues now because padata_priv and padata_list
happen to have their list fields at the same offset, but we really
shouldn't be relying on that.

Fixes: bfde23ce ("padata: unbind parallel jobs from specific CPUs")
Signed-off-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 34c3a47d

kernel/padata.c

+5 −2
Original line number Diff line number Diff line
@@ -390,13 +390,16 @@ void padata_do_serial(struct padata_priv *padata) 
	int hashed_cpu = padata_cpu_hash(pd, padata->seq_nr);

	struct padata_list *reorder = per_cpu_ptr(pd->reorder_list, hashed_cpu);

	struct padata_priv *cur;

	struct list_head *pos;



	spin_lock(&reorder->lock);

	/* Sort in ascending order of sequence number. */

	list_for_each_entry_reverse(cur, &reorder->list, list)

	list_for_each_prev(pos, &reorder->list) {

		cur = list_entry(pos, struct padata_priv, list);

		if (cur->seq_nr < padata->seq_nr)

			break;

	list_add(&padata->list, &cur->list);

	}

	list_add(&padata->list, pos);

	spin_unlock(&reorder->lock);



	/*