Add the __counted_by compiler attribute to the flexible array members devs to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE.
Increment nr_devs before adding a new device to the devs array and adjust the array indexes accordingly. In bch2_journal_read(), explicitly set nr_devs to 0. Signed-off-by: Thorsten Blum <[email protected]> --- fs/bcachefs/buckets.c | 3 ++- fs/bcachefs/journal_io.c | 3 ++- fs/bcachefs/replicas.c | 6 +++--- fs/bcachefs/replicas_format.h | 4 ++-- 4 files changed, 9 insertions(+), 7 deletions(-) diff --git a/fs/bcachefs/buckets.c b/fs/bcachefs/buckets.c index be2bbd248631..1e6badf9ddd2 100644 --- a/fs/bcachefs/buckets.c +++ b/fs/bcachefs/buckets.c @@ -740,7 +740,8 @@ static int __trigger_extent(struct btree_trans *trans, return ret; } else if (!p.has_ec) { replicas_sectors += disk_sectors; - acc_replicas_key.replicas.devs[acc_replicas_key.replicas.nr_devs++] = p.ptr.dev; + acc_replicas_key.replicas.nr_devs++; + acc_replicas_key.replicas.devs[acc_replicas_key.replicas.nr_devs - 1] = p.ptr.dev; } else { ret = bch2_trigger_stripe_ptr(trans, k, p, data_type, disk_sectors, flags); if (ret) diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c index 7664b68e6a15..d1bd883c2c55 100644 --- a/fs/bcachefs/journal_io.c +++ b/fs/bcachefs/journal_io.c @@ -1353,6 +1353,7 @@ int bch2_journal_read(struct bch_fs *c, genradix_for_each(&c->journal_entries, radix_iter, _i) { struct bch_replicas_padded replicas = { .e.data_type = BCH_DATA_journal, + .e.nr_devs = 0, .e.nr_required = 1, }; @@ -1379,7 +1380,7 @@ int bch2_journal_read(struct bch_fs *c, goto err; darray_for_each(i->ptrs, ptr) - replicas.e.devs[replicas.e.nr_devs++] = ptr->dev; + replicas.e.devs[++replicas.e.nr_devs - 1] = ptr->dev; bch2_replicas_entry_sort(&replicas.e); diff --git a/fs/bcachefs/replicas.c b/fs/bcachefs/replicas.c index 1223b710755d..90d9b7d761bc 100644 --- a/fs/bcachefs/replicas.c +++ b/fs/bcachefs/replicas.c @@ -122,7 +122,7 @@ static void extent_to_replicas(struct bkey_s_c k, continue; if (!p.has_ec) - r->devs[r->nr_devs++] = p.ptr.dev; + r->devs[++r->nr_devs - 1] = p.ptr.dev; else r->nr_required = 0; } @@ -139,7 +139,7 @@ static void stripe_to_replicas(struct bkey_s_c k, for (ptr = s.v->ptrs; ptr < s.v->ptrs + s.v->nr_blocks; ptr++) - r->devs[r->nr_devs++] = ptr->dev; + r->devs[++r->nr_devs - 1] = ptr->dev; } void bch2_bkey_to_replicas(struct bch_replicas_entry_v1 *e, @@ -180,7 +180,7 @@ void bch2_devlist_to_replicas(struct bch_replicas_entry_v1 *e, e->nr_required = 1; darray_for_each(devs, i) - e->devs[e->nr_devs++] = *i; + e->devs[++e->nr_devs - 1] = *i; bch2_replicas_entry_sort(e); } diff --git a/fs/bcachefs/replicas_format.h b/fs/bcachefs/replicas_format.h index b97208195d06..d2e080d0ecb7 100644 --- a/fs/bcachefs/replicas_format.h +++ b/fs/bcachefs/replicas_format.h @@ -5,7 +5,7 @@ struct bch_replicas_entry_v0 { __u8 data_type; __u8 nr_devs; - __u8 devs[]; + __u8 devs[] __counted_by(nr_devs); } __packed; struct bch_sb_field_replicas_v0 { @@ -17,7 +17,7 @@ struct bch_replicas_entry_v1 { __u8 data_type; __u8 nr_devs; __u8 nr_required; - __u8 devs[]; + __u8 devs[] __counted_by(nr_devs); } __packed; struct bch_sb_field_replicas { -- 2.46.0
