bcachefs: Initialize journal pad data in bch_replica_entry objects.

Running the filesystem under valgrind exposed some garbage data being
written to disk in bch2_journal_super_entries_add_common(), in the
portion which encodes bch_replica_entry objects.

Signed-off-by: Justin Husted <sigstop@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
index af6fb90413e95cc7f2e27fb2b16ab9e911e69f94..14ff191ad702402149985768c13783010fd1ff05 100644 (file)
--- a/fs/bcachefs/super-io.c
+++ b/fs/bcachefs/super-io.c
@@ -1030,9 +1030,10 @@ bch2_journal_super_entries_add_common(struct bch_fs *c,
                struct jset_entry_data_usage *u =
                        container_of(entry, struct jset_entry_data_usage, entry);
 
-               memset(u, 0, sizeof(*u));
-               u->entry.u64s   = DIV_ROUND_UP(sizeof(*u) + e->nr_devs,
-                                              sizeof(u64)) - 1;
+               int u64s = DIV_ROUND_UP(sizeof(*u) + e->nr_devs,
+                                       sizeof(u64)) - 1;
+               memset(u, 0, u64s * sizeof(u64));
+               u->entry.u64s   = u64s;
                u->entry.type   = BCH_JSET_ENTRY_data_usage;
                u->v            = cpu_to_le64(c->usage_base->replicas[i]);
                unsafe_memcpy(&u->r, e, replicas_entry_bytes(e),