Your message dated Mon, 8 Dec 2025 19:15:03 +1100
with message-id
<caly8cw7neqfgibcfh4xeb6luqtm17itghsz-vh+my5cbmta...@mail.gmail.com>
and subject line procps: [w] no "from" data and segfault with parameter -s
has caused the Debian Bug report #1053706,
regarding w: crashes because of the systemd support
to be marked as done.
This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.
(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact [email protected]
immediately.)
--
1053706: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1053706
Debian Bug Tracking System
Contact [email protected] with problems
--- Begin Message ---
Package: procps
Version: 2:4.0.4-4
Severity: normal
I noticed that w is segfaulting sometimes. Backtracing it showed the
issue. Running `w -hs` crashes. The main function passes NULL utmp entry
together with the systemd session, while later print_from expects to be
able to access the utmp data.
(gdb) r
Starting program: /tmp/procps-4.0.4/src/.libs/w -hs
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
print_host (host=host@entry=0x4c <error: Cannot access memory at address 0x4c>,
len=16, len@entry=256, fromlen=fromlen@entry=16) at src/w.c:112
112 if (*host == '\0') break;
(gdb) bt
#0 print_host (host=host@entry=0x4c <error: Cannot access memory at address
0x4c>, len=16, len@entry=256, fromlen=fromlen@entry=16) at src/w.c:112
#1 0x0000555555557371 in print_from (session=session@entry=0x0, u=u@entry=0x0,
ip_addresses=ip_addresses@entry=0, fromlen=fromlen@entry=16) at src/w.c:264
#2 0x0000555555557e6e in showinfo (session=0x5555555654d0 "1794",
name=name@entry=0x55555555d800 "lumag", u=u@entry=0x0,
formtype=formtype@entry=0, maxcmd=maxcmd@entry=156, from=from@entry=1,
userlen=8, fromlen=16, ip_addresses=0, pids=0) at src/w.c:622
#3 0x000055555555671f in main (argc=<optimized out>, argv=<optimized out>) at
src/w.c:831
(gdb) list src/w.c:831
826 if (!strcmp(name, user))
827
showinfo(sessions_list[i], name, NULL, longform,
828 maxcmd, from,
userlen, fromlen,
829 ip_addresses,
pids);
830 } else {
831 showinfo(sessions_list[i],
name, NULL, longform, maxcmd,
832 from, userlen,
fromlen, ip_addresses, pids);
833 }
834 free(name);
835 free(sessions_list[i]);
(gdb) l src/w.c:264
259 if (len) { /* IP address is non-empty, print it (and
concatenate with display, if present) */
260 fputs(buf, stdout);
261 /* show the display part of the host or IPv6
link addr. interface, if present */
262 print_display_or_interface(u->ut_host,
UT_HOSTSIZE, fromlen - len);
263 } else { /* IP address is empty, print the host instead
*/
264 print_host(u->ut_host, UT_HOSTSIZE, fromlen);
265 }
266 } else { /* -i switch NOT used */
267 print_host(u->ut_host, UT_HOSTSIZE, fromlen);
268 }
-- System Information:
Debian Release: trixie/sid
APT prefers testing
APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 6.6.15-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE,
TAINT_UNSIGNED_MODULE
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8),
LANGUAGE=en_GB:en
Shell: /bin/sh linked to /usr/bin/bash
Init: systemd (via /run/systemd/system)
Versions of packages procps depends on:
ii init-system-helpers 1.66
ii libc6 2.37-15
ii libncursesw6 6.4+20240113-1
ii libproc2-0 2:4.0.4-4
ii libsystemd0 255.4-1
ii libtinfo6 6.4+20240113-1
Versions of packages procps recommends:
ii psmisc 23.7-1
procps suggests no packages.
-- no debconf information
--- End Message ---
--- Begin Message ---
Package: procps
Version: 2:4.0.4-9
4.0.4-8 and 4.0.4-9 had fixes for w to stop it crashing on some sessions.
- Craig
--- End Message ---
