The branch stable/13 has been updated by des:
URL:
https://cgit.FreeBSD.org/src/commit/?id=1501ecebf5af7b47fde0020b888cfb4e4df1074e
commit 1501ecebf5af7b47fde0020b888cfb4e4df1074e
Author: Ed Maste <ema...@freebsd.org>
AuthorDate: 2024-11-27 20:36:46 +0000
Commit: Dag-Erling Smørgrav <d...@freebsd.org>
CommitDate: 2025-08-05 11:52:26 +0000
comsat: Improve use of setuid()
Just return from jkfprintf if either (a) user lookup fails (that is,
getpwnam fails) or (b) setuid() to the user's uid fails. If comsat is
invoked from inetd using the default of tty:tty we will now return due
to setuid() failing rather than fopen() failing.
PR: 270404
Reviewed by: kevans
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D47823
(cherry picked from commit 062b69ba045dc0fef3d9b8d73365d2798c05a480)
comsat: Use initgroups and setgid not just setuid
PR: 270404
Reviewed by: jlduran
Obtained from: NetBSD
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D47828
(cherry picked from commit d4dd9e22c13896e6b5e2a6fc78dad4f8496cc14d)
comsat: move uid/gid setting earlier
It's good to reduce privilege as early as possible.
Suggested by: jlduran
Reviewed by: jlduran
Obtained from: NetBSD
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D47869
(cherry picked from commit 91629228e3df14997df12ffc6e7be6b9964e5463)
---
libexec/comsat/comsat.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
diff --git a/libexec/comsat/comsat.c b/libexec/comsat/comsat.c
index 138881db9e4a..2358336be61a 100644
--- a/libexec/comsat/comsat.c
+++ b/libexec/comsat/comsat.c
@@ -71,7 +71,7 @@ static int debug = 0;
static char hostname[MAXHOSTNAMELEN];
-static void jkfprintf(FILE *, char[], char[], off_t);
+static void jkfprintf(FILE *, char[], off_t);
static void mailfor(char *);
static void notify(struct utmpx *, char[], off_t, int);
static void reapchildren(int);
@@ -159,6 +159,7 @@ notify(struct utmpx *utp, char file[], off_t offset, int
folder)
FILE *tp;
struct stat stb;
struct termios tio;
+ struct passwd *p;
char tty[20];
const char *s = utp->ut_line;
@@ -192,6 +193,14 @@ notify(struct utmpx *utp, char file[], off_t offset, int
folder)
}
(void)tcgetattr(fileno(tp), &tio);
cr = ((tio.c_oflag & (OPOST|ONLCR)) == (OPOST|ONLCR)) ? "\n" : "\n\r";
+
+ /* Set uid/gid/groups to user's in case mail drop is on nfs */
+ if ((p = getpwnam(utp->ut_user)) == NULL ||
+ initgroups(p->pw_name, p->pw_gid) == -1 ||
+ setgid(p->pw_gid) == -1 ||
+ setuid(p->pw_uid) == -1)
+ return;
+
switch (stb.st_mode & (S_IXUSR | S_IXGRP)) {
case S_IXUSR:
case (S_IXUSR | S_IXGRP):
@@ -200,7 +209,7 @@ notify(struct utmpx *utp, char file[], off_t offset, int
folder)
cr, utp->ut_user, (int)sizeof(hostname), hostname,
folder ? cr : "", folder ? "to " : "", folder ? file : "",
cr, cr);
- jkfprintf(tp, utp->ut_user, file, offset);
+ jkfprintf(tp, file, offset);
break;
case S_IXGRP:
(void)fprintf(tp, "\007");
@@ -216,18 +225,13 @@ notify(struct utmpx *utp, char file[], off_t offset, int
folder)
}
static void
-jkfprintf(FILE *tp, char user[], char file[], off_t offset)
+jkfprintf(FILE *tp, char file[], off_t offset)
{
unsigned char *cp, ch;
FILE *fi;
int linecnt, charcnt, inheader;
- struct passwd *p;
unsigned char line[BUFSIZ];
- /* Set effective uid to user in case mail drop is on nfs */
- if ((p = getpwnam(user)) != NULL)
- (void) setuid(p->pw_uid);
-
if ((fi = fopen(file, "r")) == NULL)
return;
