diff options
author | Helge Deller <deller@gmx.de> | 2022-07-30 21:50:18 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-09-08 12:11:37 +0300 |
commit | 989201bb8c00b222235aff04e6200230d29dc7bb (patch) | |
tree | af83ac990d597483ba3a948aa7cc614ead08acf0 /drivers/tty/vt | |
parent | 7fd8d33adbba124c7032121b082031384f91d3eb (diff) | |
download | linux-989201bb8c00b222235aff04e6200230d29dc7bb.tar.xz |
vt: Clear selection before changing the font
commit 566f9c9f89337792070b5a6062dff448b3e7977f upstream.
When changing the console font with ioctl(KDFONTOP) the new font size
can be bigger than the previous font. A previous selection may thus now
be outside of the new screen size and thus trigger out-of-bounds
accesses to graphics memory if the selection is removed in
vc_do_resize().
Prevent such out-of-memory accesses by dropping the selection before the
various con_font_set() console handlers are called.
Reported-by: syzbot+14b0e8f3fd1612e35350@syzkaller.appspotmail.com
Cc: stable <stable@kernel.org>
Tested-by: Khalid Masum <khalid.masum.92@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/r/YuV9apZGNmGfjcor@p100
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/vt')
-rw-r--r-- | drivers/tty/vt/vt.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index a4d005fa2569..0252c0562dbc 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -4671,9 +4671,11 @@ static int con_font_set(struct vc_data *vc, struct console_font_op *op) console_lock(); if (vc->vc_mode != KD_TEXT) rc = -EINVAL; - else if (vc->vc_sw->con_font_set) + else if (vc->vc_sw->con_font_set) { + if (vc_is_sel(vc)) + clear_selection(); rc = vc->vc_sw->con_font_set(vc, &font, op->flags); - else + } else rc = -ENOSYS; console_unlock(); kfree(font.data); @@ -4700,9 +4702,11 @@ static int con_font_default(struct vc_data *vc, struct console_font_op *op) console_unlock(); return -EINVAL; } - if (vc->vc_sw->con_font_default) + if (vc->vc_sw->con_font_default) { + if (vc_is_sel(vc)) + clear_selection(); rc = vc->vc_sw->con_font_default(vc, &font, s); - else + } else rc = -ENOSYS; console_unlock(); if (!rc) { |