** Description changed: == SRU Justification == - Currently, when writing + Currently, when writing 2^64-1 or 2^63 into file-max: echo 18446744073709551616 > /proc/sys/fs/file-max - /proc/sys/fs/file-max will overflow and be set to 0 and make the system - stuck with "Too many open files in system" error within seconds. + Will make the system stuck with "Too many open files in system" error + within seconds. The upper and lower limit need to be defined properly to avoid this. + (The case for passing 2^64 will be addressed in bug 1833935) This failure was reported by the case 2 and 3 of the sysctl02 test in LTP: sysctl02 2 TFAIL: /proc/sys/fs/file-max overflows and set to 18446744073709551615 sysctl02 3 TFAIL: /proc/sys/fs/file-max overflows and set to 9223372036854775808 == Fix == * 32a5ad9c sysctl: handle overflow for file-max * 9002b214 kernel/sysctl.c: fix out-of-bounds access when setting file-max These patches can be cherry-picked into B/C. They have already been applied in X/D from stable update process. == Test == Test kernel could be found here: https://people.canonical.com/~phlin/kernel/lp-1834310-file-max/ Tested OK on KVM nodes with the following command (extracted from the sysctl02 test case in LTP): $ cat /proc/sys/fs/file-max $ sudo sysctl -w -q fs.file-max=18446744073709551615 $ cat /proc/sys/fs/file-max $ sudo sysctl -w -q fs.file-max=9223372036854775808 $ cat /proc/sys/fs/file-max All three file-max output should be identical with the patched kernel. This is because the file-max value is parsed via __do_proc_doulongvec_minmax(), which does not report error when min or max are exceeded but it will just keep the old value instead. == Regression Potential == Low, just adding boundaries to the file-max. And it's been applied in some of our kernels for a while. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: linux-image-4.15.0-52-generic 4.15.0-52.56 ProcVersionSignature: User Name 4.15.0-52.56-generic 4.15.18 Uname: Linux 4.15.0-52-generic x86_64 AlsaDevices: total 0 crw-rw---- 1 root audio 116, 1 Jun 25 11:03 seq crw-rw---- 1 root audio 116, 33 Jun 25 11:03 timer AplayDevices: Error: [Errno 2] No such file or directory: 'aplay': 'aplay' ApportVersion: 2.20.9-0ubuntu7.6 Architecture: amd64 ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord': 'arecord' AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: Date: Tue Jun 25 11:04:55 2019 IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig': 'iwconfig' Lsusb: Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub MachineType: QEMU Standard PC (i440FX + PIIX, 1996) PciMultimedia: ProcFB: 0 cirrusdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-52-generic root=UUID=6f08d1c2-d443-47ee-97ca-2aeb1bf53f35 ro RelatedPackageVersions: linux-restricted-modules-4.15.0-52-generic N/A linux-backports-modules-4.15.0-52-generic N/A linux-firmware 1.173.6 RfKill: Error: [Errno 2] No such file or directory: 'rfkill': 'rfkill' SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 04/01/2014 dmi.bios.vendor: SeaBIOS dmi.bios.version: Ubuntu-1.8.2-1ubuntu1 dmi.chassis.type: 1 dmi.chassis.vendor: QEMU dmi.chassis.version: pc-i440fx-xenial dmi.modalias: dmi:bvnSeaBIOS:bvrUbuntu-1.8.2-1ubuntu1:bd04/01/2014:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-xenial:cvnQEMU:ct1:cvrpc-i440fx-xenial: dmi.product.name: Standard PC (i440FX + PIIX, 1996) dmi.product.version: pc-i440fx-xenial dmi.sys.vendor: QEMU
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1834310 Title: Handle overflow for file-max To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1834310/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
