On Sun, Aug 25, 2024 at 03:36:02PM GMT, Thorsten Blum wrote: > 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.
The nr_devs changes are pretty gross - please add a helper for that > > 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 >
