out_s3: fix NULL dereference when upload_id is unset

When upload_id is not set in create_multipart_upload() (which can occur in some failure modes), subsequent retries will segfault when checking this ID in complete_multipart_upload(). This commit simply checks that the upload ID has been set and returns the usual error code instead of crashing if not. It also logs an error message for the user. Discussed in #3838. Signed-off-by: Aaron Jacobs <[email protected]>
fluent · Aug 4, 2021 · 1a0fc10 · 1a0fc10
1 parent a7a8d21
commit 1a0fc10
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/plugins/out_s3/s3_multipart.c b/plugins/out_s3/s3_multipart.c
@@ -431,6 +431,12 @@ int complete_multipart_upload(struct flb_s3 *ctx,
     struct flb_http_client *c = NULL;
     struct flb_aws_client *s3_client;
 
+    if (!m_upload->upload_id) {
+        flb_plg_error(ctx->ins, "Cannot complete multipart upload for key %s: "
+                      "upload ID is unset ", m_upload->s3_key);
+        return -1;
+    }
+
     uri = flb_sds_create_size(flb_sds_len(m_upload->s3_key) + 11 +
                               flb_sds_len(m_upload->upload_id));
     if (!uri) {