apport information ** Tags added: apport-collected
** Description changed: I have a file located on ext4 mounted with "dax". When I call mmap on that file with protection flag different than PROT_NONE and pass the returned address to mprotect(..., PROT_NONE) it fails with: mprotect: Permission denied This bug affects PMDK (https://github.com/pmem/pmdk) and seems to be Ubuntu kernel-specific. Problem was observer on kernel 4.15.0-36-generic and 4.15.0-34-generic Below is a code which can be used to reproduce the issue. #include <sys/stat.h> #include <sys/types.h> #include <sys/mman.h> #include <stdlib.h> #include <stdio.h> #include <fcntl.h> int main(int argc, char *argv[]) { if (argc < 3) { fprintf(stderr, "usage %s file size\n", argv[0]); return 1; } int size = atoi(argv[2]); int fd = open(argv[1], O_RDWR); if (fd < 0) { perror("open"); return 1; } void *addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); if (addr == MAP_FAILED) { perror("mmap"); return 1; } if(mprotect(addr, size, PROT_NONE)) { perror("mprotect"); return 1; } return 0; } + --- + ProblemType: Bug + ApportVersion: 2.20.9-0ubuntu7.4 + Architecture: amd64 + AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: + CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found. + CurrentDesktop: ubuntu:GNOME + DistroRelease: Ubuntu 18.04 + InstallationDate: Installed on 2018-10-23 (0 days ago) + InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725) + IwConfig: + lo no wireless extensions. + + enp0s3 no wireless extensions. + Lsusb: + Bus 001 Device 002: ID 80ee:0021 VirtualBox USB Tablet + Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub + MachineType: innotek GmbH VirtualBox + Package: linux (not installed) + ProcFB: + + ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-36-generic root=UUID=48e87c4c-3028-4252-b7bb-e1e6091ff7f6 ro quiet splash + ProcVersionSignature: Ubuntu 4.15.0-36.39-generic 4.15.18 + RelatedPackageVersions: + linux-restricted-modules-4.15.0-36-generic N/A + linux-backports-modules-4.15.0-36-generic N/A + linux-firmware 1.173.1 + RfKill: + + Tags: bionic + Uname: Linux 4.15.0-36-generic x86_64 + UpgradeStatus: No upgrade log present (probably fresh install) + UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo + _MarkForUpload: True + dmi.bios.date: 12/01/2006 + dmi.bios.vendor: innotek GmbH + dmi.bios.version: VirtualBox + dmi.board.name: VirtualBox + dmi.board.vendor: Oracle Corporation + dmi.board.version: 1.2 + dmi.chassis.type: 1 + dmi.chassis.vendor: Oracle Corporation + dmi.modalias: dmi:bvninnotekGmbH:bvrVirtualBox:bd12/01/2006:svninnotekGmbH:pnVirtualBox:pvr1.2:rvnOracleCorporation:rnVirtualBox:rvr1.2:cvnOracleCorporation:ct1:cvr: + dmi.product.family: Virtual Machine + dmi.product.name: VirtualBox + dmi.product.version: 1.2 + dmi.sys.vendor: innotek GmbH ** Attachment added: "AlsaInfo.txt" https://bugs.launchpad.net/bugs/1799237/+attachment/5204640/+files/AlsaInfo.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1799237 Title: mprotect fails on ext4 with dax To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1799237/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
