summaryrefslogtreecommitdiffstats
path: root/drivers/video
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-26 10:58:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-26 10:58:20 -0700
commit15bc20c6af4ceee97a1f90b43c0e386643c071b4 (patch)
tree9d17d72e80a14552eda45027faaa2330ef6a2857 /drivers/video
parent27563ab6ef75abc64b7da2c7a321b7edd89dfcf7 (diff)
parentea1fc02e12b647d8dd7515d1dba137847d8e951d (diff)
downloadlinux-15bc20c6af4ceee97a1f90b43c0e386643c071b4.tar.bz2
Merge tag 'tty-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH: "Here are a few small TTY/Serial/vt fixes for 5.9-rc3 Included in here are: - qcom serial fixes - vt ioctl and core bugfixes - pl011 serial driver fixes - 8250 serial driver fixes - other misc serial driver fixes and for good measure: - fbcon fix for syzbot found problem. All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: tty: serial: imx: add dependence and build for earlycon serial: samsung: Removes the IRQ not found warning serial: 8250: change lock order in serial8250_do_startup() serial: stm32: avoid kernel warning on absence of optional IRQ serial: pl011: Fix oops on -EPROBE_DEFER serial: pl011: Don't leak amba_ports entry on driver register error serial: 8250_exar: Fix number of ports for Commtech PCIe cards tty: serial: qcom_geni_serial: Drop __init from qcom_geni_console_setup serial: qcom_geni_serial: Fix recent kdb hang vt_ioctl: change VT_RESIZEX ioctl to check for error return from vc_resize() fbcon: prevent user font height or width change from causing potential out-of-bounds access vt: defer kfree() of vc_screenbuf in vc_do_resize()
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/fbdev/core/fbcon.c25
1 files changed, 23 insertions, 2 deletions
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 8a31fc2b2258..66167830fefd 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2191,6 +2191,9 @@ static void updatescrollmode(struct fbcon_display *p,
}
}
+#define PITCH(w) (((w) + 7) >> 3)
+#define CALC_FONTSZ(h, p, c) ((h) * (p) * (c)) /* size = height * pitch * charcount */
+
static int fbcon_resize(struct vc_data *vc, unsigned int width,
unsigned int height, unsigned int user)
{
@@ -2200,6 +2203,24 @@ static int fbcon_resize(struct vc_data *vc, unsigned int width,
struct fb_var_screeninfo var = info->var;
int x_diff, y_diff, virt_w, virt_h, virt_fw, virt_fh;
+ if (ops->p && ops->p->userfont && FNTSIZE(vc->vc_font.data)) {
+ int size;
+ int pitch = PITCH(vc->vc_font.width);
+
+ /*
+ * If user font, ensure that a possible change to user font
+ * height or width will not allow a font data out-of-bounds access.
+ * NOTE: must use original charcount in calculation as font
+ * charcount can change and cannot be used to determine the
+ * font data allocated size.
+ */
+ if (pitch <= 0)
+ return -EINVAL;
+ size = CALC_FONTSZ(vc->vc_font.height, pitch, FNTCHARCNT(vc->vc_font.data));
+ if (size > FNTSIZE(vc->vc_font.data))
+ return -EINVAL;
+ }
+
virt_w = FBCON_SWAP(ops->rotate, width, height);
virt_h = FBCON_SWAP(ops->rotate, height, width);
virt_fw = FBCON_SWAP(ops->rotate, vc->vc_font.width,
@@ -2652,7 +2673,7 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font,
int size;
int i, csum;
u8 *new_data, *data = font->data;
- int pitch = (font->width+7) >> 3;
+ int pitch = PITCH(font->width);
/* Is there a reason why fbconsole couldn't handle any charcount >256?
* If not this check should be changed to charcount < 256 */
@@ -2668,7 +2689,7 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font,
if (fbcon_invalid_charcount(info, charcount))
return -EINVAL;
- size = h * pitch * charcount;
+ size = CALC_FONTSZ(h, pitch, charcount);
new_data = kmalloc(FONT_EXTRA_WORDS * sizeof(int) + size, GFP_USER);