Cache: reset c->body_start when reading a variant on Vary mismatch.
Previously, a variant not present in shared memory and stored on disk using a
secondary key was read using c->body_start from a variant stored with a main
key. This could result in critical errors "cache file .. has too long header".
diff --git a/src/http/ngx_http_cache.h b/src/http/ngx_http_cache.h
index cd0b4bb..d010a4e 100644
--- a/src/http/ngx_http_cache.h
+++ b/src/http/ngx_http_cache.h
@@ -80,6 +80,7 @@
ngx_str_t vary;
u_char variant[NGX_HTTP_CACHE_KEY_LEN];
+ size_t buffer_size;
size_t header_start;
size_t body_start;
off_t length;
diff --git a/src/http/ngx_http_file_cache.c b/src/http/ngx_http_file_cache.c
index e985f27..7a5b4ca 100644
--- a/src/http/ngx_http_file_cache.c
+++ b/src/http/ngx_http_file_cache.c
@@ -294,6 +294,8 @@
cln->data = c;
}
+ c->buffer_size = c->body_start;
+
rc = ngx_http_file_cache_exists(cache, c);
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
@@ -1230,7 +1232,7 @@
c->secondary = 1;
c->file.name.len = 0;
- c->body_start = c->buf->end - c->buf->start;
+ c->body_start = c->buffer_size;
ngx_memcpy(c->key, c->variant, NGX_HTTP_CACHE_KEY_LEN);