git: 3a9010c98b3d - stable/13 - calendar: don't setlogin(2) in the -a user handlers

The branch stable/13 has been updated by kevans:

URL: https://cgit.FreeBSD.org/src/commit/?id=3a9010c98b3d9676307fac20d42cdd3cfd4bc46d

commit 3a9010c98b3d9676307fac20d42cdd3cfd4bc46d
Author:     Kyle Evans <kevans@FreeBSD.org>
AuthorDate: 2024-08-05 18:43:56 +0000
Commit:     Kyle Evans <kevans@FreeBSD.org>
CommitDate: 2024-08-08 20:00:40 +0000

    calendar: don't setlogin(2) in the -a user handlers
    
    As of e67975d331 ("Fix 'calendar -a' in several ways."), `calendar -a`
    will now fork off a new process for each user and do all of its own
    processing in the user's own context.
    
    As a side-effect, calendar(1) started calling setlogin(2) in each of the
    forked processes and inadvertently hijacked the login name for the
    session it was running under, which was typically not a fresh session
    but rather that of whatever cron/periodic run spawned it.  Thus, daily
    and security e-mails started coming from completely arbitrary user.
    
    We could create a new session, but it appears that nothing calendar(1)
    does really needs the login name to be clobbered; opt to just avoid the
    setlogin(2) call entirely rather than incur the overhead of a new
    session for each process.
    
    PR:             280418
    Reviewed by:    des, olce
    Fixes:          e67975d331 ("Fix 'calendar -a' in several ways.")
    
    (cherry picked from commit 6cb8b61efe8899ee9194563108d0ae90c1eb89e3)
---
 usr.bin/calendar/calendar.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/usr.bin/calendar/calendar.c b/usr.bin/calendar/calendar.c
index 476c0495d218..2e3baee7d57f 100644
--- a/usr.bin/calendar/calendar.c
+++ b/usr.bin/calendar/calendar.c
@@ -224,7 +224,7 @@ main(int argc, char *argv[])
 
 				lc = login_getpwclass(pw);
 				if (setusercontext(lc, pw, pw->pw_uid,
-				    LOGIN_SETALL) != 0)
+				    LOGIN_SETALL & ~LOGIN_SETLOGIN) != 0)
 					errx(1, "setusercontext");
 				setenv("HOME", pw->pw_dir, 1);
 				cal();