Crash after editor exit and updating panels at display_mini_info

[alex2172]

(1) mc --version
GNU Midnight Commander 4.8.15
Built with GLib 2.47.3

(2) How to reproduce:

• F4 to enter editor (vim), edit some, exit.
• crash with probability ~0.01..0.1

(3) Detailed info:

(gdb) where
#0  0x000055a508be31c5 in display_mini_info (panel=0x55a509457800) at panel.c:1024
#1  0x000055a508be8c87 in panel_callback (w=0x55a509457800, sender=<optimized out>, msg=<optimized out>, parm=<optimized out>, data=<optimized out>) at panel.c:3630
#2  0x000055a508bc78ed in send_message (data=0x0, parm=0, msg=MSG_DRAW, sender=0x0, w=<optimized out>) at ../../lib/widget/widget-common.h:167
...

(4) More detailed info: bug is here

else if (DIR_IS_DOTDOT (panel->dir.list[panel->selected].fname))
(gdb) print panel->dir.list[panel->selected].fname
$12 = 0x0

(gdb) print panel->dir.list[panel->selected]
$13 = {fnamelen = 7, fname = 0x0, st = {st_dev = 2066, st_ino = 104334693, st_nlink = 4, st_mode = 16893, st_uid = 1000, st_gid = 1000, __pad0 = 0, st_rdev = 0, st_size = 4096, st_blksize = 4096,
    st_blocks = 8, st_atim = {tv_sec = 1551612512, tv_nsec = 718435921}, st_mtim = {tv_sec = 1492950780, tv_nsec = 791025993}, st_ctim = {tv_sec = 1492950780, tv_nsec = 791025993},
    __glibc_reserved = {0, 0, 0}}, sort_key = 0x0, second_sort_key = 0x0, f = {marked = 0, link_to_dir = 0, stale_link = 0, dir_size_computed = 0}}

[andrew_b]

Replying to alex2172:

GNU Midnight Commander 4.8.15

Recent version is 4.8.22.

Perhaps, this is fixed in #3943.

[zaytsev]

Ubuntu bug with full backtraces:

​https://bugs.launchpad.net/mc/+bug/1601999

Indeed fixed in #3943 and released in 4.8.22.