From a4d1779b5ee28b1c27c509a1baebf881943cad1b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Wed, 5 Dec 2018 22:52:53 +0100
Subject: [PATCH] =?UTF-8?q?journald:=20lower=20the=20maximum=20entry=20siz?=
 =?UTF-8?q?e=20limit=20to=20=C2=BD=20for=20non-sealed=20fds?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

We immediately read the whole contents into memory, making thigs much more
expensive. Sealed fds should be used instead since they are more efficient
on our side.

(cherry-picked from commit 6670c9de196c8e2d5e84a8890cbb68f70c4db6e3)

Related: #1664977
---
 src/journal/journald-native.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/journal/journald-native.c b/src/journal/journald-native.c
index 110ab3641c..da62448ca6 100644
--- a/src/journal/journald-native.c
+++ b/src/journal/journald-native.c
@@ -380,8 +380,10 @@ void server_process_native_file(
         if (st.st_size <= 0)
                 return;
 
-        if (st.st_size > ENTRY_SIZE_MAX) {
-                log_error("File passed too large. Ignoring.");
+        /* When !sealed, set a lower memory limit. We have to read the file,
+         * effectively doubling memory use. */
+        if (st.st_size > ENTRY_SIZE_MAX / (sealed ? 1 : 2)) {
+                log_error("File passed too large (%"PRIu64" bytes). Ignoring.", (uint64_t) st.st_size);
                 return;
         }