Commit 253ba178 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Fix ca->oldest_gen allocation 



The ca->oldest_gen array needs to be the same size as the bucket_gens
array; ca->mi.nbuckets is updated with only state_lock held, not
gc_lock, so bch2_gc_gens() could race with device resize and allocate
too small of an oldest_gens array.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent a1d97d84

fs/bcachefs/btree_gc.c

+2 −4
Original line number Diff line number Diff line
@@ -1954,19 +1954,17 @@ int bch2_gc_gens(struct bch_fs *c) 
	trans = bch2_trans_get(c);



	for_each_member_device(ca, c, i) {

		struct bucket_gens *gens;

		struct bucket_gens *gens = bucket_gens(ca);



		BUG_ON(ca->oldest_gen);



		ca->oldest_gen = kvmalloc(ca->mi.nbuckets, GFP_KERNEL);

		ca->oldest_gen = kvmalloc(gens->nbuckets, GFP_KERNEL);

		if (!ca->oldest_gen) {

			percpu_ref_put(&ca->ref);

			ret = -BCH_ERR_ENOMEM_gc_gens;

			goto err;

		}



		gens = bucket_gens(ca);



		for (b = gens->first_bucket;

		     b < gens->nbuckets; b++)

			ca->oldest_gen[b] = gens->b[b];