[pbs-devel] [PATCH proxmox-rrd] cache: skip non-utf8 lines in rrd journal

[Christian Ebner]

In certain situations garbage might be written to the rrd journal,
e.g. by a hard crash of the host.
Therefore, skip not only non-parsable lines, as is already the case,
but also skip over lines containing non-utf8 contents.

Reported in the community forum:
https://forum.proxmox.com/threads/149542/

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
Tested by writing garbage to the `rrd.journal` located at
`/var/lib/proxmox-backup/rrdb` via `dd`.

Not only does this lead to the summary graphs in the WebUI not being
updated anymore, but also the systemd journal is being spammed with
apply old journal messages after a reboot, potentially filling up the
available disk space.

 proxmox-rrd/src/cache.rs | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/proxmox-rrd/src/cache.rs b/proxmox-rrd/src/cache.rs
index 5b123a6b..96c92fd8 100644
--- a/proxmox-rrd/src/cache.rs
+++ b/proxmox-rrd/src/cache.rs
@@ -280,11 +280,21 @@ fn apply_journal_lines(
     loop {
         linenr += 1;
         let mut line = String::new();
-        let len = if lock_read_line {
+        let result = if lock_read_line {
             let _lock = state.read().unwrap(); // make sure we read entire lines
-            reader.read_line(&mut line)?
+            reader.read_line(&mut line)
         } else {
-            reader.read_line(&mut line)?
+            reader.read_line(&mut line)
+        };
+
+        let len = match result {
+            Ok(len) => len,
+            Err(err) => {
+                log::warn!(
+                    "unable to parse rrd journal '{journal_name}' line {linenr} (skip) - {err}",
+                );
+                continue;
+            }
         };
 
         if len == 0 {
-- 
2.39.2