From: Alejandro Colomar <alx@kernel.org>
Date: Mon, 5 Feb 2024 12:54:25 +0000 (+0100)
Subject: src/login.c: Fix off-by-one bugss
X-Git-Tag: 4.15.0-rc2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=15882a5f904b3c277d73254a6953c1051db55df4;p=thirdparty%2Fshadow.git

src/login.c: Fix off-by-one bugss

These functions expect a size, not a length.  Don't subtract 1 to the
size.

Link: <https://github.com/shadow-maint/shadow/pull/935>
Link: <https://github.com/shadow-maint/shadow/issues/920#issuecomment-1926002209>
Link: <https://github.com/shadow-maint/shadow/pull/757>
Link: <https://github.com/shadow-maint/shadow/issues/674>
See-also: 0656a90bfd0d ("src/login.c: Fix off-by-one buggs")
See-also: 403a2e3771be ("lib/chkname.c: Take NUL byte into account")
Fixes: 3b7cc053872c ("lib: replace `USER_NAME_MAX_LENGTH` macro")
Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Tobias Stoeckmann <tobias@stoeckmann.org>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
---

diff --git a/src/login.c b/src/login.c
index c1bc5633d..9ae86a7fd 100644
--- a/src/login.c
+++ b/src/login.c
@@ -577,7 +577,7 @@ int main (int argc, char **argv)
 		assert (NULL == username);
 		username = XMALLOC(max_size, char);
 		username[max_size - 1] = '\0';
-		if (do_rlogin(hostname, username, max_size - 1, term, sizeof(term)))
+		if (do_rlogin(hostname, username, max_size, term, sizeof(term)))
 		{
 			preauth_flag = true;
 		} else {
@@ -890,7 +890,7 @@ int main (int argc, char **argv)
 			preauth_flag = false;
 			username = XMALLOC(max_size, char);
 			username[max_size - 1] = '\0';
-			login_prompt(username, max_size - 1);
+			login_prompt(username, max_size);
 
 			if ('\0' == username[0]) {
 				/* Prompt for a new login */