bcachefs: fix bch2_journal_keys_peek_prev_min() underflow

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2025-06-24 16:04:32 -04:00
parent f5109c201c
commit 1f8aede70d

View File

@ -137,12 +137,15 @@ struct bkey_i *bch2_journal_keys_peek_prev_min(struct bch_fs *c, enum btree_id b
struct journal_key *k;
BUG_ON(*idx > keys->nr);
if (!keys->nr)
return NULL;
search:
if (!*idx)
*idx = __bch2_journal_key_search(keys, btree_id, level, pos);
while (*idx < keys->nr &&
__journal_key_cmp(btree_id, level, end_pos, idx_to_key(keys, *idx - 1)) >= 0) {
__journal_key_cmp(btree_id, level, end_pos, idx_to_key(keys, *idx)) >= 0) {
(*idx)++;
iters++;
if (iters == 10) {
@ -151,18 +154,23 @@ search:
}
}
if (*idx == keys->nr)
--(*idx);
struct bkey_i *ret = NULL;
rcu_read_lock(); /* for overwritten_ranges */
while ((k = *idx < keys->nr ? idx_to_key(keys, *idx) : NULL)) {
while (true) {
k = idx_to_key(keys, *idx);
if (__journal_key_cmp(btree_id, level, end_pos, k) > 0)
break;
if (k->overwritten) {
if (k->overwritten_range)
*idx = rcu_dereference(k->overwritten_range)->start - 1;
else
*idx -= 1;
*idx = rcu_dereference(k->overwritten_range)->start;
if (!*idx)
break;
--(*idx);
continue;
}
@ -171,6 +179,8 @@ search:
break;
}
if (!*idx)
break;
--(*idx);
iters++;
if (iters == 10) {