diff options
| author | George Kennedy <george.kennedy@oracle.com> | 2020-07-31 18:33:12 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-18 13:22:56 +0200 |
| commit | bc5269ca765057a1b762e79a1cfd267cd7bf1c46 (patch) | |
| tree | 9ed7a7d56752ac10910a56dc51505f0b1d2d8c65 /drivers/tty/vt | |
| parent | fbcon: prevent user font height or width change from causing potential out-of... (diff) | |
| download | linux-bc5269ca765057a1b762e79a1cfd267cd7bf1c46.tar.xz linux-bc5269ca765057a1b762e79a1cfd267cd7bf1c46.zip | |
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@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/vt')
| -rw-r--r-- | drivers/tty/vt/vt_ioctl.c | 12 |
1 files changed, 11 insertions, 1 deletions
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(); } |