Public bug reported: When a program is running in an overlayfs, /proc/self/maps reports the wrong path. Notably, it lacks a prefix equal to the mountpoint of the overlayfs. This only happens on linux-gcp-5.13, it does not reproduce on non-gcp kernels.
Small repro: cat > repro.sh <<EOF #!/usr/bin/env bash mkdir -p /tmp/overlay mkdir -p /tmp/work mkdir -p /tmp/upper mkdir -p /tmp/lower mount -t overlay overlay /tmp/overlay -o lowerdir=/tmp/lower,upperdir=/tmp/upper,workdir=/tmp/work cp $(which cat) /tmp/overlay /tmp/overlay/cat /proc/self/maps | grep '\/tmp\/overlay\/cat' if [ $? -ne 0 ]; then echo 'Bug!' else echo 'No bug!' fi umount /tmp/overlay EOF sudo bash repro.sh ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: linux-image-5.13.0-1019-gcp 5.13.0-1019.23~20.04.1 ProcVersionSignature: Ubuntu 5.13.0-1019.23~20.04.1-gcp 5.13.19 Uname: Linux 5.13.0-1019-gcp x86_64 ApportVersion: 2.20.11-0ubuntu27.21 Architecture: amd64 CasperMD5CheckResult: skip Date: Thu Mar 10 01:49:37 2022 ProcEnviron: TERM=alacritty PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=C.UTF-8 SHELL=/bin/bash SourcePackage: linux-signed-gcp-5.13 UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: linux-signed-gcp-5.13 (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug focal uec-images -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1964426 Title: Wrong path reported in /proc/self/maps with overlayfs To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed-gcp-5.13/+bug/1964426/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs