whois: fdsan: attempted to close file descriptor

[Dmole]

Problem description
Steps to reproduce

whois 127.0.0.1 > /dev/null
fdsan: attempted to close file descriptor 3, expected to be unowned, actually owned by FILE* 0x7130a40578
Aborted

Expected behavior

whois 127.0.0.1 > /dev/null

Additional information

termux-info
Packages CPU architecture:
aarch64
Subscribed repositories:
# sources.list
deb https://termux.org/packages/ stable main
# game-repo (sources.list.d/game.list)
deb https://dl.bintray.com/grimler/game-packages-24 games stable
# science-repo (sources.list.d/science.list)
deb https://dl.bintray.com/grimler/science-packages-24 science stable
Updatable packages:
All packages up to date
Android version:
11
Kernel build information:
Linux localhost 4.4.223-ga176abe6ae2a-ab6713882 #1 SMP PREEMPT Tue Jul 28 04:51:17 UTC 2020 aarch64 Android
Device manufacturer:
Google
Device model:
Pixel 2

[ghost]

Same as #5790, related to https://developer.android.com/about/versions/11/behavior-changes-all.

[Grimler91]

gdb --args whois 127.0.0.1 with debug build of inetutils give

[...]

fdsan: attempted to close file descriptor 3, expected to be unowned, actually owned by FILE* 0xb6c7b00c

Program received signal SIGABRT, Aborted.
0xb6b959e8 in fdsan_error(char const*, ...) () from /apex/com.android.runtime/lib/bionic/libc.so
(gdb) bt
#0  0xb6b959e8 in fdsan_error(char const*, ...) () from /apex/com.android.runtime/lib/bionic/libc.so
#1  0xb6b956fe in android_fdsan_close_with_tag () from /apex/com.android.runtime/lib/bionic/libc.so
#2  0xb6b95d6e in close () from /apex/com.android.runtime/lib/bionic/libc.so
#3  0x7f55866a in closeconn (fd=3) at /home/builder/.termux-build/inetutils/src/whois/whois.c:601
#4  0x7f55816a in main (argc=-1, argv=0xbefff50c) at /home/builder/.termux-build/inetutils/src/whois/whois.c:294

whois.c is smaller than emacs and texlive so a bit easier to dig into.

How the file descriptor is handled looks reasonable in the main function. Maybe the sanitizer does not like that the fd is obtained/replaced multiple times in a for loop in openconn.

[ghost]

Fixed in 1.9.4-11.