Bug#1003257: screen: segfaults ("screen caught signal 11. (core dumped)])") when run with no arguments/-r

[Axel Beckert]

Control: tag -1 + moreinfo

Dear наб,

наб wrote:
> Subject: screen: segfaults ("screen caught signal 11. (core
> dumped)])") when run with no arguments/-r
>
> I freshly installed screen. I don't think I have any pre-existing
> configuration on this machine.

Not for screen, the strace output confirms that.

> I also don't think I have any weird system config.

I nevertheless suspect from the strace (thanks for that!) that this is
cause as screen seems to choke on the file /etc/terminfo/s/st-256color:

> 498447 access("/etc/terminfo/s/st-256color", R_OK) = 0
> 498447 openat(AT_FDCWD, "/etc/terminfo/s/st-256color", O_RDONLY) = 5
> 498447 fstat(5, {st_mode=S_IFREG|0644, st_size=2559, ...}) = 0
> 498447 read(5, "\32\1(\0\35\0\17\0i\1W\6st-256color| simplet"..., 30720) = 2559
> 498447 read(5, "", 28160) = 0
> 498447 close(5) = 0
> 498447 ioctl(2, TCGETS, 0x7ffd960a2290) = -1 ENOTTY (Inappropriate ioctl for device)
> 498447 ioctl(2, TCGETS, 0x7ffd960a2220) = -1 ENOTTY (Inappropriate ioctl for device)
> 498447 geteuid() = 1000
> 498447 getegid() = 100
> 498447 ioctl(3, TIOCGWINSZ, {ws_row=54, ws_col=172, ws_xpixel=1204, ws_ypixel=810}) = 0
> 498447 --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=NULL} ---

But /etc/terminfo/README says:

This directory is for system-local terminfo descriptions. By default,
ncurses will search ${HOME}/.terminfo first, then /etc/terminfo (this
directory), then /lib/terminfo, and last not least
/usr/share/terminfo.

And I can't find any Debian package shipping any file in that
directory besides ncurses-base which ships the above mentioned
/etc/terminfo/README file.

Can you please check if moving away this file (and potentially further
files in the same directory) temporarily (e.g. to
/root/terminfo-backup/ or so) solves the issue?

If this helps, I'd be happy if you could post
/etc/terminfo/s/st-256color to this bug report (or send it me in
private if you don't want to have it publically archived) so that I
can figure out what part of the terminal definitions makes screen
crash and report that part to the upstream developers.

Regards, Axel
--
,''`. | Axel Beckert <a...@debian.org>, https://people.debian.org/~abe/
: :' : | Debian Developer, ftp.ch.debian.org Admin
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