Public bug reported:
When running `sudo update-grub`, os-prober fails with a shared library
error, preventing Windows detection in dual-boot systems.
1) Release of Ubuntu: Ubuntu 26.04 LTS
2) Package version:
libgcc-s1: 16-20260322-1ubuntu1
os-prober: 1.84ubuntu1
coreutils: 9.5-1ubuntu2+0.0.0~ubuntu25
3) What I expected to happen:
Running `sudo update-grub` should detect all bootable operating systems
(including Windows) and add them to the GRUB boot menu.
4) What happened instead:
The command produced the following errors:
```
mktemp: error while loading shared libraries: libgcc_s.so.1: failed to map
segment from shared object
/usr/bin/os-prober: 17: cannot create /dmraid-map: Permission denied
```
Windows was not detected and does not appear in the GRUB menu.
Steps to reproduce:
1. Have a dual-boot system with Ubuntu and Windows installed (UEFI mode)
(Windows installed first)
2. Run `sudo update-grub`
3. Observe the `libgcc_s.so.1` mapping error in the output
4. Windows does not appear in the GRUB menu
Workaround attempted:
- Reinstalled libgcc-s1, coreutils, and os-prober (did not resolve)
- Remounted /tmp with exec (already had exec by default)
- Manually added Windows entry to /etc/grub.d/40_custom (this worked)
Additional info:
- /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi exists and is accessible
- /tmp is mounted as tmpfs with rw,nosuid,nodev (no noexec flag)
This appears to be a dynamic linker or library mapping issue affecting
mktemp within os-prober.
ProblemType: Bug
DistroRelease: Ubuntu 26.04
Package: os-prober 1.84ubuntu1
ProcVersionSignature: Ubuntu 7.0.0-28.28-generic 7.0.12
Uname: Linux 7.0.0-28-generic x86_64
ApportVersion: 2.34.1-0ubuntu0.1
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Tue Aug 4 00:12:49 2026
InstallationDate: Installed on 2026-06-29 (35 days ago)
InstallationMedia: Ubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423.1)
ProcEnviron:
LANG=en_US.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
SourcePackage: os-prober
UpgradeStatus: No upgrade log present (probably fresh install)
** Affects: os-prober (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug resolute wayland-session
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https://bugs.launchpad.net/bugs/2162775
Title:
`os-prober` crashes with `libgcc_s.so.1: failed to map segment error`,
preventing Windows detection in GRUB
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