In order to compact tables we need at least two tables. Bail out early from `reftable_stack_auto_compact()` in case we have less than two tables. This is mostly defense in depth: `stack_table_sizes_for_compaction()` may try to allocate a zero-byte object when there aren't any readers, and that may lead to a `NULL` pointer on some platforms like NonStop which causes us to bail out with an out-of-memory error. Signed-off-by: Patrick Steinhardt <ps@xxxxxx> --- reftable/stack.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/reftable/stack.c b/reftable/stack.c index 59fd695a12c2033ed589a21ef1c9155eeecc4641..6ca21965d8e1135d986043113d465abd14cd532c 100644 --- a/reftable/stack.c +++ b/reftable/stack.c @@ -1627,6 +1627,9 @@ int reftable_stack_auto_compact(struct reftable_stack *st) struct segment seg; uint64_t *sizes; + if (st->merged->readers_len < 2) + return 0; + sizes = stack_table_sizes_for_compaction(st); if (!sizes) return REFTABLE_OUT_OF_MEMORY_ERROR; -- 2.48.0.rc0.184.g0fc57dec57.dirty
