diff --git a/cpp/src/arrow/compute/exec/key_map.cc b/cpp/src/arrow/compute/exec/key_map.cc
index f06a090cf85..bff352e0155 100644
--- a/cpp/src/arrow/compute/exec/key_map.cc
+++ b/cpp/src/arrow/compute/exec/key_map.cc
@@ -510,7 +510,7 @@ void SwissTable::find(const int num_keys, const uint32_t* hashes,
     return;
   }
 
-  auto slot_ids_buf = util::TempVectorHolder<uint32_t>(temp_stack_, num_ids);
+  auto slot_ids_buf = util::TempVectorHolder<uint32_t>(temp_stack_, num_keys);
   uint32_t* slot_ids = slot_ids_buf.mutable_data();
   init_slot_ids(num_ids, ids, hashes, local_slots, inout_match_bitvector, slot_ids);
 
diff --git a/cpp/src/arrow/compute/exec/util.h b/cpp/src/arrow/compute/exec/util.h
index ed89bece6a3..55f9a7e14c9 100644
--- a/cpp/src/arrow/compute/exec/util.h
+++ b/cpp/src/arrow/compute/exec/util.h
@@ -89,24 +89,35 @@ class TempVectorStack {
     // using SIMD when number of vector elements is not divisible
     // by the number of SIMD lanes.
     //
-    return ::arrow::BitUtil::RoundUp(num_bytes, sizeof(int64_t)) + padding;
+    return ::arrow::BitUtil::RoundUp(num_bytes, sizeof(int64_t)) + kPadding;
   }
   void alloc(uint32_t num_bytes, uint8_t** data, int* id) {
     int64_t old_top = top_;
-    top_ += PaddedAllocationSize(num_bytes);
+    top_ += PaddedAllocationSize(num_bytes) + 2 * sizeof(uint64_t);
     // Stack overflow check
     ARROW_DCHECK(top_ <= buffer_size_);
-    *data = buffer_->mutable_data() + old_top;
+    *data = buffer_->mutable_data() + old_top + sizeof(uint64_t);
+    // We set 8 bytes before the beginning of the allocated range and
+    // 8 bytes after the end to check for stack overflow (which would
+    // result in those known bytes being corrupted).
+    reinterpret_cast<uint64_t*>(buffer_->mutable_data() + old_top)[0] = kGuard1;
+    reinterpret_cast<uint64_t*>(buffer_->mutable_data() + top_)[-1] = kGuard2;
     *id = num_vectors_++;
   }
   void release(int id, uint32_t num_bytes) {
     ARROW_DCHECK(num_vectors_ == id + 1);
-    int64_t size = PaddedAllocationSize(num_bytes);
+    int64_t size = PaddedAllocationSize(num_bytes) + 2 * sizeof(uint64_t);
+    ARROW_DCHECK(reinterpret_cast<const uint64_t*>(buffer_->mutable_data() + top_)[-1] ==
+                 kGuard2);
     ARROW_DCHECK(top_ >= size);
     top_ -= size;
+    ARROW_DCHECK(reinterpret_cast<const uint64_t*>(buffer_->mutable_data() + top_)[0] ==
+                 kGuard1);
     --num_vectors_;
   }
-  static constexpr int64_t padding = 64;
+  static constexpr uint64_t kGuard1 = 0x3141592653589793ULL;
+  static constexpr uint64_t kGuard2 = 0x0577215664901532ULL;
+  static constexpr int64_t kPadding = 64;
   int num_vectors_;
   int64_t top_;
   std::unique_ptr<Buffer> buffer_;