video: omapfb: Use scnprintf() for avoiding potential buffer overflow

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311093230.24900-2-tiwai@suse.de
This commit is contained in:
Takashi Iwai 2020-03-11 10:32:28 +01:00 committed by Bartlomiej Zolnierkiewicz
parent 0666a8d7f6
commit bf1b615ad9

View File

@ -1247,7 +1247,7 @@ static ssize_t omapfb_show_caps_num(struct device *dev,
size = 0;
while (size < PAGE_SIZE && plane < OMAPFB_PLANE_NUM) {
omapfb_get_caps(fbdev, plane, &caps);
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
"plane#%d %#010x %#010x %#010x\n",
plane, caps.ctrl, caps.plane_color, caps.wnd_color);
plane++;
@ -1268,28 +1268,28 @@ static ssize_t omapfb_show_caps_text(struct device *dev,
size = 0;
while (size < PAGE_SIZE && plane < OMAPFB_PLANE_NUM) {
omapfb_get_caps(fbdev, plane, &caps);
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
"plane#%d:\n", plane);
for (i = 0; i < ARRAY_SIZE(ctrl_caps) &&
size < PAGE_SIZE; i++) {
if (ctrl_caps[i].flag & caps.ctrl)
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
" %s\n", ctrl_caps[i].name);
}
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
" plane colors:\n");
for (i = 0; i < ARRAY_SIZE(color_caps) &&
size < PAGE_SIZE; i++) {
if (color_caps[i].flag & caps.plane_color)
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
" %s\n", color_caps[i].name);
}
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
" window colors:\n");
for (i = 0; i < ARRAY_SIZE(color_caps) &&
size < PAGE_SIZE; i++) {
if (color_caps[i].flag & caps.wnd_color)
size += snprintf(&buf[size], PAGE_SIZE - size,
size += scnprintf(&buf[size], PAGE_SIZE - size,
" %s\n", color_caps[i].name);
}