Comment 0 for bug 1656259

  bash -c 'ulimit -f 1024; yes | head -n2097152' >/path/on/filesystem/under/test

On ext4, this test case prints something along the lines of:

  bash: line 1: 11274 Broken pipe yes
       11275 File size limit exceeded(core dumped) | head -n2097152

On ZFS, this test case incorrectly exits zero with no output, demonstrating that ZFS does not respect RLIMIT_FSIZE.

I asked a friend to run this on Solaris 5.10 and FreeBSD 10.0-CURRENT, and on those systems this test case correctly generates SIGXFSZ; so it seems that this is a bug in the Linux port of ZFS.

(This was discovered while tracking down Launchpad test suite failures under LXD on ZFS. Launchpad uses RLIMIT_FSIZE in one place to guard against bugs that cause debdiff to generate arbitrarily large amounts of output and fill the disk.)

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.4.0-57-generic 4.4.0-57.78
ProcVersionSignature: Ubuntu 4.4.0-57.78-generic 4.4.35
Uname: Linux 4.4.0-57-generic x86_64
NonfreeKernelModules: zfs zunicode zcommon znvpair zavl
ApportVersion: 2.20.1-0ubuntu2.4
Architecture: amd64
CurrentDesktop: Unity
Date: Fri Jan 13 10:01:36 2017
EcryptfsInUse: Yes
HibernationDevice: RESUME=UUID=139ad421-b014-4c34-ae8c-dd1d15205875
InstallationDate: Installed on 2013-03-01 (1413 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130223.1)
MachineType: LENOVO 20BXCTO1WW
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-57-generic.efi.signed root=UUID=12c52021-a1ab-4984-9dd7-63cf0dcaac16 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-4.4.0-57-generic N/A
 linux-backports-modules-4.4.0-57-generic N/A
 linux-firmware 1.157.6
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/21/2015
dmi.bios.vendor: LENOVO
dmi.bios.version: JBET49WW (1.14 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20BXCTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: SDK0E50512 STD
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrJBET49WW(1.14):bd05/21/2015:svnLENOVO:pn20BXCTO1WW:pvrThinkPadT450s:rvnLENOVO:rn20BXCTO1WW:rvrSDK0E50512STD:cvnLENOVO:ct10:cvrNone:
dmi.product.name: 20BXCTO1WW
dmi.product.version: ThinkPad T450s
dmi.sys.vendor: LENOVO