From 8ed11b21e54417a450c64914a3898ce75c243c7f Mon Sep 17 00:00:00 2001 From: Ed Maste Date: Tue, 26 May 2026 12:19:47 -0400 Subject: vt: Avoid integer overflow in CONS_HISTORY ioctl Approved by: re (cperciva) Approved by: so Security: FreeBSD-SA-26:34.vt Security: CVE-2026-49416 Reviewed by: markj, vexeduxr Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D57250 (cherry picked from commit 0ae946e7223df5ef3f7980af1d774d7f593f6421) (cherry picked from commit deaaddf1d3c4283649945553ad7e3208c8424308) --- sys/dev/vt/vt_buf.c | 9 ++++----- sys/dev/vt/vt_core.c | 6 ++++-- 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/sys/dev/vt/vt_buf.c b/sys/dev/vt/vt_buf.c index e1e4ebc23491..43657fcecbdc 100644 --- a/sys/dev/vt/vt_buf.c +++ b/sys/dev/vt/vt_buf.c @@ -499,7 +499,6 @@ vtbuf_grow(struct vt_buf *vb, const term_pos_t *p, unsigned int history_size) { term_char_t *old, *new, **rows, **oldrows, **copyrows, *row, *oldrow; unsigned int w, h, c, r, old_history_size; - size_t bufsize, rowssize; int history_full; const teken_attr_t *a; term_char_t ch; @@ -510,10 +509,10 @@ vtbuf_grow(struct vt_buf *vb, const term_pos_t *p, unsigned int history_size) history_size = MAX(history_size, p->tp_row); /* Allocate new buffer. */ - bufsize = history_size * p->tp_col * sizeof(term_char_t); - new = malloc(bufsize, M_VTBUF, M_WAITOK | M_ZERO); - rowssize = history_size * sizeof(term_pos_t *); - rows = malloc(rowssize, M_VTBUF, M_WAITOK | M_ZERO); + new = mallocarray(history_size, p->tp_col * sizeof(term_char_t), + M_VTBUF, M_WAITOK | M_ZERO); + rows = mallocarray(history_size, sizeof(term_pos_t *), M_VTBUF, + M_WAITOK | M_ZERO); /* Toggle it. */ VTBUF_LOCK(vb); diff --git a/sys/dev/vt/vt_core.c b/sys/dev/vt/vt_core.c index 8360f0b80fb5..922b44028a23 100644 --- a/sys/dev/vt/vt_core.c +++ b/sys/dev/vt/vt_core.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include #include @@ -2798,8 +2799,9 @@ skip_thunk: /* XXX */ return (0); case CONS_HISTORY: - if (*(int *)data < 0) - return EINVAL; + if (*(int *)data < 0 || + *(int *)data > UINT_MAX / USHRT_MAX / sizeof(term_char_t)) + return (EINVAL); if (*(int *)data != vw->vw_buf.vb_history_size) vtbuf_sethistory_size(&vw->vw_buf, *(int *)data); return (0); -- cgit v1.3