[pve-devel] [PATCH common] safe_read_from: bump default size limit to 512k

[Fabian Grünbichler]

this is (via file_get_contents and file_copy) used for reading from
pmxcfs, which has a file size limit of 512k. since quite a number of
call sites would need to explicitly override this (and then get updated
if we bump the limit on the pmxcfs side again in the future), making our
default file reader compatible by default seems the better solution.

Signed-off-by: Fabian Grünbichler <f.gruenbichler at proxmox.com>
---

Notes:
    actual real-world example of hitting this issue:
    
    https://forum.proxmox.com/threads/backup-failed-file-etc-pve-firewall-100-fw-too-long-aborting.74348/

 src/PVE/Tools.pm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/PVE/Tools.pm b/src/PVE/Tools.pm
index 4399b2f..5d53127 100644
--- a/src/PVE/Tools.pm
+++ b/src/PVE/Tools.pm
@@ -288,7 +288,8 @@ sub file_read_firstline {
 sub safe_read_from {
     my ($fh, $max, $oneline, $filename) = @_;
 
-    $max = 32768 if !$max;
+    # pmxcfs file size limit
+    $max = 512*1024 if !$max;
 
     my $subject = defined($filename) ? "file '$filename'" : 'input';
 
-- 
2.20.1