shadow/libmisc
Alejandro Colomar 5c5dc75641 libmisc: agetpass(): Fix bug detecting truncation
On 2/19/23 18:09, David Mudrich wrote:
> I am working on a RAM based Linux OS from source, and try to use
> latest versions of all software.  I found shadow needs libbsd's
> readpassphrase(3) as superior alternative to getpass(3).  While
> considering if I a) include libbsd, or include libbsd's code of
> readpassphrase(3) into shadow, found, that libbsd's readpassphrase(3)
> never returns \n or \r
> <https://cgit.freedesktop.org/libbsd/tree/src/readpassphrase.c>
> line 122, while agetpass() uses a check for \n in agetpass.c line 108.
> I assume it always fails.

Indeed, it always failed.  I made a mistake when writing agetpass(),
assuming that readpassphrase(3) would keep newlines.

>
> I propose a check of len == PASS_MAX - 1, with false positive error for
> exactly PASS_MAX - 1 long passwords.

Instead, I added an extra byte to the allocation to allow a maximum
password length of PASS_MAX (which is the maximum for getpass(3), which
we're replacing.

While doing that, I notice that my previous implementation also had
another bug (minor): The maximum password length was PASS_MAX - 1
instead of PASS_MAX.  That's also fixed in this commit.

Reported-by: David Mudrich <dmudrich@gmx.de>
Fixes: 155c9421b9 ("libmisc: agetpass(), erase_pass(): Add functions for getting passwords safely")
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2023-02-20 12:16:01 +01:00
..
.indent.pro Commit the last version from the PLD CVS repository. 2007-10-07 14:36:51 +00:00
addgrps.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
age.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
agetpass.c libmisc: agetpass(): Fix bug detecting truncation 2023-02-20 12:16:01 +01:00
audit_help.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
basename.c Update licensing info 2021-12-23 19:36:50 -06:00
bit.c Add bit manipulation functions 2023-01-30 18:24:15 +01:00
btrfs.c Declare read-only data const 2022-08-06 11:27:56 -05:00
chkname.c shadow: use relaxed usernames 2022-09-02 20:27:14 -05:00
chkname.h Update licensing info 2021-12-23 19:36:50 -06:00
chowndir.c Avoid races in chown_tree() 2022-08-17 12:34:01 -05:00
chowntty.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
cleanup_group.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
cleanup_user.c Fix typos 2023-02-16 13:23:08 -06:00
cleanup.c Update licensing info 2021-12-23 19:36:50 -06:00
console.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
copydir.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
csrand.c Unoptimize the higher part of the domain of csrand_uniform() 2023-01-30 18:24:15 +01:00
date_to_str.c Use strlcpy(3) instead of its pattern 2022-12-22 18:03:39 -06:00
entry.c Call NULL by its name 2023-02-02 13:08:30 -06:00
env.c Call NULL by its name 2023-02-02 13:08:30 -06:00
failure.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
failure.h Disable utmpx permanently 2022-12-22 10:31:43 +01:00
find_new_gid.c find_new_[gu]id(): Skip over IDs that are reserved for legacy reasons 2023-02-20 12:10:02 +01:00
find_new_sub_gids.c Don't redefine errno(3) 2022-12-22 11:43:29 +01:00
find_new_sub_uids.c Don't redefine errno(3) 2022-12-22 11:43:29 +01:00
find_new_uid.c find_new_[gu]id(): Skip over IDs that are reserved for legacy reasons 2023-02-20 12:10:02 +01:00
getdate.h Update licensing info 2021-12-23 19:36:50 -06:00
getdate.y Use isdigit(3) instead of a reimplementation of it 2021-12-29 02:41:09 +01:00
getgr_nam_gid.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
getrange.c Declare read-only parameters const 2022-08-06 11:27:56 -05:00
gettime.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
hushed.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
idmapping.c Use stpeprintf() where appropriate 2023-02-16 11:29:33 +01:00
idmapping.h Add include for uid_t 2022-08-06 11:27:56 -05:00
isexpired.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
limits.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
list.c Call NULL by its name 2023-02-02 13:08:30 -06:00
log.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
loginprompt.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
mail.c Update licensing info 2021-12-23 19:36:50 -06:00
Makefile.am Add stpecpy() 2023-02-16 11:29:33 +01:00
mempcpy.c Add mempcpy(3) 2023-02-16 11:29:33 +01:00
motd.c Drop register keyword 2022-08-06 11:27:56 -05:00
myname.c Update licensing info 2021-12-23 19:36:50 -06:00
obscure.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
pam_pass_non_interactive.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
pam_pass.c Don't redefine errno(3) 2022-12-22 11:43:29 +01:00
prefix_flag.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
pwd2spwd.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
pwd_init.c Assume SIGTTOU is defined 2022-12-15 16:22:05 -06:00
pwdcheck.c Call NULL by its name 2023-02-02 13:08:30 -06:00
remove_tree.c Avoid races in remove_tree() 2022-08-17 12:34:01 -05:00
rlogin.c Assume B[0-9]* macros are defined 2022-12-15 16:22:05 -06:00
root_flag.c libmisc/root_flag: add tips for --root flag only support abspath 2022-08-06 15:04:06 -05:00
salt.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
setugid.c Update licensing info 2021-12-23 19:36:50 -06:00
setupenv.c Merge pull request #451 from hallyn/2021-12-05/license 2022-01-02 18:38:42 -06:00
shell.c Call NULL by its name 2023-02-02 13:08:30 -06:00
stpecpy.c Add stpecpy() 2023-02-16 11:29:33 +01:00
stpeprintf.c Add stpeprintf() 2023-02-16 11:29:33 +01:00
strtoday.c strtoday.c: remove unused defines.h inclusion 2022-12-22 10:39:45 -06:00
sub.c Update licensing info 2021-12-23 19:36:50 -06:00
sulog.c Call NULL by its name 2023-02-02 13:08:30 -06:00
ttytype.c ttytype(): Fix race 2023-02-09 10:03:03 -06:00
tz.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
ulimit.c Remove comments that survived the Helicoprion 2022-12-15 16:22:05 -06:00
user_busy.c Fix typo 2023-02-16 13:23:08 -06:00
utmp.c Remove superfluous casts 2023-02-09 10:03:03 -06:00
valid.c Update licensing info 2021-12-23 19:36:50 -06:00
xgetgrgid.c Fix comments 2023-02-16 13:23:08 -06:00
xgetgrnam.c Fix comments 2023-02-16 13:23:08 -06:00
xgetpwnam.c libmisc: fix grammar 2023-01-26 22:44:39 -06:00
xgetpwuid.c Fix comments 2023-02-16 13:23:08 -06:00
xgetspnam.c Fix comments 2023-02-16 13:23:08 -06:00
xgetXXbyYY.c Fix comments 2023-02-16 13:23:08 -06:00
xmalloc.c Don't test for NULL before calling free(3) 2022-09-29 16:03:53 +02:00
yesno.c Remove superfluous casts 2023-02-09 10:03:03 -06:00