diff options
| author | Ed Maste <emaste@FreeBSD.org> | 2024-02-26 15:38:45 +0000 |
|---|---|---|
| committer | Gordon Tetlow <gordon@FreeBSD.org> | 2024-03-28 03:12:16 +0000 |
| commit | a3ec3054762f0e7bf2381a7939e62c5e43fde935 (patch) | |
| tree | 9a2785e80f3e65511efb1cd0c782a463c8c3ec39 | |
| parent | adfda3c395faf108d76ef7772db3804bee5b228f (diff) | |
kern: fix panic with disabled ttys
PR: 277240, 277329
Reviewed by: kib (earlier version)
Fixes: f1d0a0cbecf2 ("jail: Fix information leak.")
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D44086
Approved by: so
Security: FreeBSD-EN-24:05.tty
(cherry picked from commit 975d7730828a8bde28c2a0092b6e95c4c4e22f34)
(cherry picked from commit 8d22744f5be165a2a82a2a204789e44bbdc5a2ee)
| -rw-r--r-- | sys/kern/tty.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sys/kern/tty.c b/sys/kern/tty.c index 673904570b86..df42c08d949e 100644 --- a/sys/kern/tty.c +++ b/sys/kern/tty.c @@ -1312,7 +1312,8 @@ sysctl_kern_ttys(SYSCTL_HANDLER_ARGS) struct xtty *xtlist, *xt; struct tty *tp; struct proc *p; - int cansee, error; + int error; + bool cansee; sx_slock(&tty_list_sx); lsize = tty_list_count * sizeof(struct xtty); @@ -1325,8 +1326,8 @@ sysctl_kern_ttys(SYSCTL_HANDLER_ARGS) TAILQ_FOREACH(tp, &tty_list, t_list) { tty_lock(tp); - if (tp->t_session != NULL) { - p = tp->t_session->s_leader; + if (tp->t_session != NULL && + (p = atomic_load_ptr(&tp->t_session->s_leader)) != NULL) { PROC_LOCK(p); cansee = (p_cansee(td, p) == 0); PROC_UNLOCK(p); |