Dear Maintainer,
the attached file in message #5 contains
a backtrace with this part [1].
I am quite sure that the call to __fdelt_chk in g_spawn_sync is
at this source location [2] in gspawn.c line 442.
Because __fdelt_chk checks if the fd outpipe is either
negative or below FD_SETSIZE, and outpipe is just checked
before to be greater or equal to zero, I would assume that
this process did run out of file descriptors.
If that is really the case might be visible if one checks
the output of 'lsof | grep $(pidof pidgin)'.
Upstream glib has fixed this FD_SETSIZE limitation in [4].
The last link shows a backtrace with the same
g_spawn_sync/__fdelt_chk combination.
Therefore I would assume current testing should not show this fault.
Kind regards,
Bernhard
[1]
...
#5 0x00007fe1c2aca940 in __GI___chk_fail () at chk_fail.c:28
#6 0x00007fe1c2acc737 in __fdelt_chk (d=<optimized out>) at fdelt_chk.c:25
#7 0x00007fe1c2f021c5 in g_spawn_sync () from
/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#8 0x00007fe1c2f02997 in g_spawn_command_line_sync () from
/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#9 0x00007fe1c2db1794 in purple_gnome_proxy_get_parameter
(parameter=parameter@entry=0 '\000', gnome_version=gnome_version@entry=1
'\001') at ././libpurple/proxy.c:270
#10 0x00007fe1c2db1e2b in purple_gnome_proxy_get_parameter
(gnome_version=<optimized out>, parameter=0 '\000') at ././libpurple/proxy.c:307
...
[2]
(gdb) list gspawn.c:360,450
...
440 FD_ZERO (&fds);
441 if (outpipe >= 0)
442 FD_SET (outpipe, &fds); <<<<<<<<<<<<
443 if (errpipe >= 0)
444 FD_SET (errpipe, &fds);
...
https://sources.debian.org/src/glib2.0/2.58.3-2+deb10u2/glib/gspawn.c/#L442
[3]
long int
__fdelt_chk (long int d)
{
if (d < 0 || d >= FD_SETSIZE)
__chk_fail ();
return d / __NFDBITS;
}
[4]
https://gitlab.gnome.org/GNOME/glib/-/issues/954
https://gitlab.gnome.org/GNOME/glib/-/commit/a7242d4a5e5e5875699bcff2749beac19864943b
https://gitlab.gnome.org/GNOME/glib/-/issues/2079
# Buster/stable amd64 qemu VM 2020-08-20
apt update
apt dist-upgrade
apt install systemd-coredump sddm xserver-xorg openbox xterm mc dpkg-dev
devscripts gdb pidgin
reboot
cat /proc/sys/kernel/randomize_va_space
echo 0 > /proc/sys/kernel/randomize_va_space
wget
https://snapshot.debian.org/archive/debian/20190822T033017Z/pool/main/g/glib2.0/libglib2.0-data_2.58.3-2%2Bdeb10u1_all.deb
wget
https://snapshot.debian.org/archive/debian/20190822T033017Z/pool/main/g/glib2.0/libglib2.0-0_2.58.3-2%2Bdeb10u1_amd64.deb
wget
https://snapshot.debian.org/archive/debian-debug/20190928T162431Z/pool/main/g/glib2.0/libglib2.0-0-dbgsym_2.58.3-2%2Bdeb10u1_amd64.deb
dpkg -i *.deb
mkdir /home/benutzer/source/libglib2.0-0/orig -p
cd /home/benutzer/source/libglib2.0-0/orig
dget
https://snapshot.debian.org/archive/debian/20190821T220217Z/pool/main/g/glib2.0/glib2.0_2.58.3-2%2Bdeb10u1.dsc
cd
mkdir /home/benutzer/source/pidgin/orig -p
cd /home/benutzer/source/pidgin/orig
apt source pidgin
cd
mkdir /home/benutzer/source/glibc/orig -p
cd /home/benutzer/source/glibc/orig
apt source glibc
cd
export DISPLAY=:0
pidgin
gdb -q --pid $(pidof pidgin)
set width 0
set pagination off
directory /home/benutzer/source/libglib2.0-0/orig/glib2.0-2.58.3/glib
disassemble g_spawn_sync
b *0x00007ffff71221c0
(gdb) b *0x00007ffff71221c0
Breakpoint 1 at 0x7ffff71221c0: file ../../../glib/gspawn.c, line 442.
(gdb) list gspawn.c:360,450
360 gboolean
361 g_spawn_sync (const gchar *working_directory,
362 gchar **argv,
363 gchar **envp,
364 GSpawnFlags flags,
365 GSpawnChildSetupFunc child_setup,
366 gpointer user_data,
367 gchar **standard_output,
368 gchar **standard_error,
369 gint *exit_status,
370 GError **error)
371 {
372 gint outpipe = -1;
373 gint errpipe = -1;
374 GPid pid;
375 fd_set fds;
376 gint ret;
377 GString *outstr = NULL;
378 GString *errstr = NULL;
379 gboolean failed;
380 gint status;
381
382 g_return_val_if_fail (argv != NULL, FALSE);
383 g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE);
384 g_return_val_if_fail (standard_output == NULL ||
385 !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE);
386 g_return_val_if_fail (standard_error == NULL ||
387 !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE);
388
389 /* Just to ensure segfaults if callers try to use
390 * these when an error is reported.
391 */
392 if (standard_output)
393 *standard_output = NULL;
394
395 if (standard_error)
396 *standard_error = NULL;
397
398 if (!fork_exec_with_pipes (FALSE,
399 working_directory,
400 argv,
401 envp,
402 !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
403 (flags & G_SPAWN_SEARCH_PATH) != 0,
404 (flags & G_SPAWN_SEARCH_PATH_FROM_ENVP) !=
0,
405 (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
406 (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
407 (flags & G_SPAWN_CHILD_INHERITS_STDIN) !=
0,
408 (flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
409 (flags & G_SPAWN_CLOEXEC_PIPES) != 0,
410 child_setup,
411 user_data,
412 &pid,
413 NULL,
414 standard_output ? &outpipe : NULL,
415 standard_error ? &errpipe : NULL,
416 error))
417 return FALSE;
418
419 /* Read data from child. */
420
421 failed = FALSE;
422
423 if (outpipe >= 0)
424 {
425 outstr = g_string_new (NULL);
426 }
427
428 if (errpipe >= 0)
429 {
430 errstr = g_string_new (NULL);
431 }
432
433 /* Read data until we get EOF on both pipes. */
434 while (!failed &&
435 (outpipe >= 0 ||
436 errpipe >= 0))
437 {
438 ret = 0;
439
440 FD_ZERO (&fds);
441 if (outpipe >= 0)
442 FD_SET (outpipe, &fds); <<<<<<<<<<<<
443 if (errpipe >= 0)
444 FD_SET (errpipe, &fds);
445
446 ret = select (MAX (outpipe, errpipe) + 1,
447 &fds,
448 NULL, NULL,
449 NULL /* no timeout */);
450
