This is a note to let you know that I've just added the patch titled

vt_ioctl: change VT_RESIZEX ioctl to check for error return from

to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From bc5269ca765057a1b762e79a1cfd267cd7bf1c46 Mon Sep 17 00:00:00 2001

From: George Kennedy george.kennedy@oracle.com Date: Fri, 31 Jul 2020 12:33:12 -0400 Subject: vt_ioctl: change VT_RESIZEX ioctl to check for error return from vc_resize()

vc_resize() can return with an error after failure. Change VT_RESIZEX ioctl to save struct vc_data values that are modified and restore the original values in case of error.

Signed-off-by: George Kennedy george.kennedy@oracle.com Cc: stable stable@vger.kernel.org Reported-by: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/1596213192-6635-2-git-send-email-george.kennedy@or... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/vt/vt_ioctl.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c index 91c301775047..a4e520bdd521 100644 --- a/drivers/tty/vt/vt_ioctl.c +++ b/drivers/tty/vt/vt_ioctl.c @@ -806,12 +806,22 @@ static int vt_resizex(struct vc_data *vc, struct vt_consize __user *cs) console_lock(); vcp = vc_cons[i].d; if (vcp) { + int ret; + int save_scan_lines = vcp->vc_scan_lines; + int save_font_height = vcp->vc_font.height; + if (v.v_vlin) vcp->vc_scan_lines = v.v_vlin; if (v.v_clin) vcp->vc_font.height = v.v_clin; vcp->vc_resize_user = 1; - vc_resize(vcp, v.v_cols, v.v_rows); + ret = vc_resize(vcp, v.v_cols, v.v_rows); + if (ret) { + vcp->vc_scan_lines = save_scan_lines; + vcp->vc_font.height = save_font_height; + console_unlock(); + return ret; + } } console_unlock(); }