Segmentation fault in FileSystemWatcher::updateWatchedDirectories on Fedora 42 - appimagelauncherd crashes repeatedly #735
Description
Pre-submit checks
- I checked for similar issues beforehand, but could not find any, not even closed ones. I could not add my bug report to any existing issue.
- I am going to take the time to to fill in all the required details. I know that the bug report will be dismissed otherwise.
Describe the bug
The appimagelauncherd service crashes repeatedly with a segmentation fault (signal 11) in the FileSystemWatcher::updateWatchedDirectories function. The crash occurs consistently every time the service attempts to start, creating a restart loop.
Expected behavior
The appimagelauncherd service should start and run without crashing, monitoring directories for AppImage files.
Steps to reproduce the issue
- Install AppImageLauncher on Fedora 42
- The service starts automatically via systemd
- Service crashes immediately with segmentation fault
- systemd attempts to restart the service (restart counter reaches 6+)
- Process repeats indefinitely
Screenshots
Journalctl logs
Can you figure out what is the issue?
---------------------------
Aug 12 09:42:05 fedora appimagelauncherd[6555]: Watching directories: /home/ankk98/Applications /home/ankk98/Downloads
Aug 12 09:42:34 fedora audit[6555]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=3 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=6555 comm="appimagelaunche" exe="/usr/bin/appimagelauncherd" sig=11 res=1
Aug 12 09:42:34 fedora kernel: traps: appimagelaunche[6555] general protection fault ip:7fee9bc368a4 sp:7ffd9bd48188 error:0 in libstdc++.so.6.0.34[368a4,7fee9bc00000+141000]
Aug 12 09:42:34 fedora systemd-coredump[6594]: Process 6555 (appimagelaunche) of user 1000 terminated abnormally with signal 11/SEGV, processing...
Aug 12 09:42:34 fedora audit: BPF prog-id=95 op=LOAD
Aug 12 09:42:34 fedora audit: BPF prog-id=96 op=LOAD
Aug 12 09:42:34 fedora audit: BPF prog-id=97 op=LOAD
Aug 12 09:42:34 fedora systemd[1]: Started [email protected] - Process Core Dump (PID 6594/UID 0).
Aug 12 09:42:34 fedora audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=systemd-coredump@5-6594-0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Aug 12 09:42:34 fedora systemd-coredump[6595]: Removed old coredump core.appimagelaunche.1000.4586c4627f3d4eb685da88737b6e1b98.12170.1754453719000000.zst.
Aug 12 09:42:34 fedora systemd-coredump[6595]: [🡕] Process 6555 (appimagelaunche) of user 1000 dumped core.
Module libdatrie.so.1 from rpm libdatrie-0.2.13-11.fc42.x86_64
Module libblkid.so.1 from rpm util-linux-2.40.4-7.fc42.x86_64
Module libcrypt.so.2 from rpm libxcrypt-4.4.38-7.fc42.x86_64
Module libXau.so.6 from rpm libXau-1.0.12-2.fc42.x86_64
Module libthai.so.0 from rpm libthai-0.1.29-10.fc42.x86_64
Module libfribidi.so.0 from rpm fribidi-1.0.16-2.fc42.x86_64
Module libpangoft2-1.0.so.0 from rpm pango-1.56.4-1.fc42.x86_64
Module liblzma.so.5 from rpm xz-5.8.1-2.fc42.x86_64
Module libjpeg.so.62 from rpm libjpeg-turbo-3.1.0-2.fc42.x86_64
Module libselinux.so.1 from rpm libselinux-3.8-2.fc42.x86_64
Module libmount.so.1 from rpm util-linux-2.40.4-7.fc42.x86_64
Module libgmodule-2.0.so.0 from rpm glib2-2.84.3-1.fc42.x86_64
Module libbz2.so.1 from rpm bzip2-1.0.8-20.fc42.x86_64
Module libbrotlicommon.so.1 from rpm brotli-1.1.0-6.fc42.x86_64
Module libsasl2.so.3 from rpm cyrus-sasl-2.1.28-30.fc42.x86_64
Module libevent-2.1.so.7 from rpm libevent-2.1.12-15.fc42.x86_64
Module libkeyutils.so.1 from rpm keyutils-1.6.3-5.fc42.x86_64
Module libkrb5support.so.0 from rpm krb5-1.21.3-6.fc42.x86_64
Module libcom_err.so.2 from rpm e2fsprogs-1.47.2-3.fc42.x86_64
Module libk5crypto.so.3 from rpm krb5-1.21.3-6.fc42.x86_64
Module libkrb5.so.3 from rpm krb5-1.21.3-6.fc42.x86_64
Module libunistring.so.5 from rpm libunistring-1.1-9.fc42.x86_64
Module libicudata.so.76 from rpm icu-76.1-4.fc42.x86_64
Module libcap.so.2 from rpm libcap-2.73-2.fc42.x86_64
Module libpixman-1.so.0 from rpm pixman-0.46.2-1.fc42.x86_64
Module libxcb-shm.so.0 from rpm libxcb-1.17.0-5.fc42.x86_64
Module libxcb-render.so.0 from rpm libxcb-1.17.0-5.fc42.x86_64
Module libxcb.so.1 from rpm libxcb-1.17.0-5.fc42.x86_64
Module libXrender.so.1 from rpm libXrender-0.9.12-2.fc42.x86_64
Module libfontconfig.so.1 from rpm fontconfig-2.16.0-2.fc42.x86_64
Module libffi.so.8 from rpm libffi-3.4.6-5.fc42.x86_64
Module libpango-1.0.so.0 from rpm pango-1.56.4-1.fc42.x86_64
Module libpangocairo-1.0.so.0 from rpm pango-1.56.4-1.fc42.x86_64
Module libxml2.so.2 from rpm libxml2-2.12.10-1.fc42.x86_64
Module libdav1d.so.7 from rpm dav1d-1.5.1-1.fc42.x86_64
Module libcairo-gobject.so.2 from rpm cairo-1.18.2-3.fc42.x86_64
Module libgdk_pixbuf-2.0.so.0 from rpm gdk-pixbuf2-2.42.12-12.fc42.x86_64
Module libgio-2.0.so.0 from rpm glib2-2.84.3-1.fc42.x86_64
Module libgraphite2.so.3 from rpm graphite2-1.3.14-18.fc42.x86_64
Module libfreetype.so.6 from rpm freetype-2.13.3-2.fc42.x86_64
Module libGLdispatch.so.0 from rpm libglvnd-1.7.0-7.fc42.x86_64
Module libXext.so.6 from rpm libXext-1.3.6-3.fc42.x86_64
Module libX11.so.6 from rpm libX11-1.8.12-1.fc42.x86_64
Module libGLX.so.0 from rpm libglvnd-1.7.0-7.fc42.x86_64
Module libbrotlidec.so.1 from rpm brotli-1.1.0-6.fc42.x86_64
Module libgssapi_krb5.so.2 from rpm krb5-1.21.3-6.fc42.x86_64
Module libcrypto.so.3 from rpm openssl-3.2.4-4.fc42.x86_64
Module libssl.so.3 from rpm openssl-3.2.4-4.fc42.x86_64
Module libpsl.so.5 from rpm libpsl-0.21.5-5.fc42.x86_64
Module libssh.so.4 from rpm libssh-0.11.2-1.fc42.x86_64
Module libidn2.so.0 from rpm libidn2-2.3.8-1.fc42.x86_64
Module libnghttp2.so.14 from rpm nghttp2-1.64.0-3.fc42.x86_64
Module libzstd.so.1 from rpm zstd-1.5.7-1.fc42.x86_64
Module libpcre2-16.so.0 from rpm pcre2-10.45-1.fc42.x86_64
Module libicuuc.so.76 from rpm icu-76.1-4.fc42.x86_64
Module libicui18n.so.76 from rpm icu-76.1-4.fc42.x86_64
Module libdouble-conversion.so.3 from rpm double-conversion-3.3.1-1.fc42.x86_64
Module libsystemd.so.0 from rpm systemd-257.7-1.fc42.x86_64
Module libcairo.so.2 from rpm cairo-1.18.2-3.fc42.x86_64
Module libgobject-2.0.so.0 from rpm glib2-2.84.3-1.fc42.x86_64
Module librsvg-2.so.2 from rpm librsvg2-2.60.0-1.fc42.x86_64
Module libharfbuzz.so.0 from rpm harfbuzz-10.4.0-1.fc42.x86_64
Module libz.so.1 from rpm zlib-ng-2.2.4-3.fc42.x86_64
Module libpng16.so.16 from rpm libpng-1.6.44-2.fc42.x86_64
Module libGL.so.1 from rpm libglvnd-1.7.0-7.fc42.x86_64
Module libcurl.so.4 from rpm curl-8.11.1-5.fc42.x86_64
Module libdbus-1.so.3 from rpm dbus-1.16.0-3.fc42.x86_64
Module libpcre2-8.so.0 from rpm pcre2-10.45-1.fc42.x86_64
Module libQt5Core.so.5 from rpm qt5-qtbase-5.15.17-1.fc42.x86_64
Module libQt5Gui.so.5 from rpm qt5-qtbase-5.15.17-1.fc42.x86_64
Module libQt5Widgets.so.5 from rpm qt5-qtbase-5.15.17-1.fc42.x86_64
Module libQt5DBus.so.5 from rpm qt5-qtbase-5.15.17-1.fc42.x86_64
Module libglib-2.0.so.0 from rpm glib2-2.84.3-1.fc42.x86_64
Stack trace of thread 6555:
#0 0x00007fee9bc368a4 _ZSt18_Rb_tree_incrementPSt18_Rb_tree_node_base (libstdc++.so.6 + 0x368a4)
#1 0x000000000041cd58 _ZN17FileSystemWatcher24updateWatchedDirectoriesESt3setI4QDir14QDirComparatorSaIS1_EE (/usr/bin/appimagelauncherd + 0x1cd58)
#2 0x000000000040bc00 _ZN9QtPrivate18QFunctorSlotObjectIZ4mainEUlvE1_Li0ENS_4ListIJEEEvE4implEiPNS_15QSlotObjectBaseEP7QObjectPPvPb (/usr/bin/appimagelauncherd + 0xbc00)
#3 0x00007fee9c254c35 _Z10doActivateILb0EEvP7QObjectiPPv (libQt5Core.so.5 + 0x254c35)
#4 0x00007fee9c25900d _ZN6QTimer7timeoutENS_14QPrivateSignalE (libQt5Core.so.5 + 0x25900d)
#5 0x00007fee9c24c57f _ZN7QObject5eventEP6QEvent (libQt5Core.so.5 + 0x24c57f)
#6 0x00007fee9c21f226 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x21f226)
#7 0x00007fee9c273b7c _ZN14QTimerInfoList14activateTimersEv (libQt5Core.so.5 + 0x273b7c)
#8 0x00007fee9c2744e1 _ZL23idleTimerSourceDispatchP8_GSourcePFiPvES1_ (libQt5Core.so.5 + 0x2744e1)
#9 0x00007fee9de62880 g_main_context_dispatch_unlocked.lto_priv.0 (libglib-2.0.so.0 + 0x40880)
#10 0x00007fee9de6b7c8 g_main_context_iterate_unlocked.isra.0 (libglib-2.0.so.0 + 0x497c8)
#11 0x00007fee9de6b973 g_main_context_iteration (libglib-2.0.so.0 + 0x49973)
#12 0x00007fee9c274867 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x274867)
#13 0x00007fee9c21dbc2 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x21dbc2)
#14 0x00007fee9c225fa4 _ZN16QCoreApplication4execEv (libQt5Core.so.5 + 0x225fa4)
#15 0x000000000040a620 main (/usr/bin/appimagelauncherd + 0xa620)
#16 0x00007fee9ba12575 __libc_start_call_main (libc.so.6 + 0x3575)
#17 0x00007fee9ba12628 __libc_start_main@@GLIBC_2.34 (libc.so.6 + 0x3628)
#18 0x000000000040ac49 _start (/usr/bin/appimagelauncherd + 0xac49)
ELF object binary architecture: AMD x86-64
Aug 12 09:42:34 fedora systemd[1]: [email protected]: Deactivated successfully.
Aug 12 09:42:34 fedora audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=systemd-coredump@5-6594-0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Aug 12 09:42:34 fedora systemd[3864]: appimagelauncherd.service: Main process exited, code=dumped, status=11/SEGV
Aug 12 09:42:34 fedora systemd[3864]: appimagelauncherd.service: Failed with result 'core-dump'.
Aug 12 09:42:35 fedora audit: BPF prog-id=97 op=UNLOAD
Aug 12 09:42:35 fedora audit: BPF prog-id=96 op=UNLOAD
Aug 12 09:42:35 fedora audit: BPF prog-id=95 op=UNLOAD
Aug 12 09:42:35 fedora abrt-dump-journal-core[2080]: Failed to obtain all required information from journald
Aug 12 09:42:35 fedora abrt-dump-journal-core[2080]: Failed to obtain all required information from journald
Aug 12 09:42:35 fedora abrt-server[6605]: Package 'appimagelauncher' isn't signed with proper key
Aug 12 09:42:35 fedora abrt-server[6605]: 'post-create' on '/var/spool/abrt/ccpp-2025-08-12-09:42:35.301102-6555' exited with 1
Aug 12 09:42:35 fedora abrt-server[6605]: Deleting problem directory '/var/spool/abrt/ccpp-2025-08-12-09:42:35.301102-6555'
Aug 12 09:42:36 fedora abrt-dump-journal-oops[2082]: abrt-dump-journal-oops: Found oopses: 1
Aug 12 09:42:36 fedora abrt-dump-journal-oops[2082]: abrt-dump-journal-oops: Creating problem directories
Aug 12 09:42:36 fedora abrt-server[6608]: Package 'kernel-core' isn't signed with proper key
Aug 12 09:42:36 fedora abrt-server[6608]: 'post-create' on '/var/spool/abrt/oops-2025-08-12-09:42:36-2082-0' exited with 1
Aug 12 09:42:36 fedora abrt-server[6608]: Deleting problem directory '/var/spool/abrt/oops-2025-08-12-09:42:36-2082-0'
Aug 12 09:42:37 fedora abrt-dump-journal-oops[2082]: Reported 1 kernel oopses to Abrt
Aug 12 09:42:45 fedora systemd[3864]: appimagelauncherd.service: Scheduled restart job, restart counter is at 6.
Distribution and desktop environment
ankk98@fedora:~$ fastfetch
.',;::::;,'. ankk98@fedora
.';:cccccccccccc:;,. -------------
.;cccccccccccccccccccccc;. OS: Fedora Linux 42 (Workstation Edition) x86_64
.:cccccccccccccccccccccccccc:. Host: ROG Flow Z13 GZ302EA_GZ302EA (1.0)
.;ccccccccccccc;.:dddl:.;ccccccc;. Kernel: Linux 6.16.0-264.vanilla.fc42.x86_64
.:ccccccccccccc;OWMKOOXMWd;ccccccc:. Uptime: 14 mins
.:ccccccccccccc;KMMc;cc;xMMc;ccccccc:. Packages: 2885 (rpm), 23 (flatpak)
,cccccccccccccc;MMM.;cc;;WW:;cccccccc, Shell: bash 5.2.37
:cccccccccccccc;MMM.;cccccccccccccccc: Display (TL134ADXP03): 2560x1600 @ 180 Hz (as 1464x915) in 13" [Built-in]
:ccccccc;oxOOOo;MMM000k.;cccccccccccc: Display (C24F390): 1920x1080 @ 60 Hz in 23" [External] *
cccccc;0MMKxdd:;MMMkddc.;cccccccccccc; DE: GNOME 48.4
ccccc;XMO';cccc;MMM.;cccccccccccccccc' WM: Mutter (Wayland)
ccccc;MMo;ccccc;MMW.;ccccccccccccccc; WM Theme: Adwaita
ccccc;0MNc.ccc.xMMd;ccccccccccccccc; Theme: Adwaita [GTK2/3/4]
cccccc;dNMWXXXWM0:;cccccccccccccc:, Icons: Adwaita [GTK2/3/4]
cccccccc;.:odl:.;cccccccccccccc:,. Font: Adwaita Sans (11pt) [GTK2/3/4]
ccccccccccccccccccccccccccccc:'. Cursor: Adwaita (24px)
:ccccccccccccccccccccccc:;,.. Terminal: Ptyxis 48.5
':cccccccccccccccc::;,. Terminal Font: Adwaita Mono (11pt)
CPU: AMD RYZEN AI MAX 390 (24) @ 5.06 GHz
GPU: AMD Radeon 8050S Graphics [Integrated]
Memory: 3.16 GiB / 22.85 GiB (14%)
Swap: 0 B / 48.00 GiB (0%)
Disk (/): 165.39 GiB / 389.62 GiB (42%) - btrfs
Disk (/run/media/ankk98/Ankk98 SSD): 127.61 GiB / 232.77 GiB (55%) - vfat
Disk (/run/media/ankk98/Ankk98 SSD Part 3): 314.06 GiB / 465.82 GiB (67%) - fuseblk
Local IP (wlp194s0): 192.168.0.113/24
Battery (ASUS Battery): 100% [AC Connected]
Locale: en_US.UTF-8
Installed AppImageLauncher version
2.2.0-travis995~0f91801
List of AppImages you tried
No response
Additional context
Additional context
- The crash occurs in the C++ standard library's red-black tree implementation (
std::_Rb_tree_increment) - This suggests memory corruption or iterator invalidation in a
std::maporstd::setcontainer - The issue appears to be in the directory watching functionality when updating watched directories
- The crash is consistent and prevents the daemon from functioning at all
- Similar issues have been reported for other distributions but not specifically this crash location