[PATCH v2 1/5] drm/modes: parse_cmdline: Handle empty mode name part

From: Geert Uytterhoeven
Date: Thu Jul 14 2022 - 06:39:20 EST


If no mode name part was specified, mode_end is zero, and the "ret ==
mode_end" check does the wrong thing.

Fix this by skipping all named mode handling when mode_end is zero.

Fixes: 7b1cce760afe38b4 ("drm/modes: parse_cmdline: Allow specifying stand-alone options")
Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Acked-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
v2:
- Add Reviewed-by, Acked-by,
- Keep "ret == mode_end" check.
---
drivers/gpu/drm/drm_modes.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 14b746f7ba975954..67773740c74c9ba0 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1823,7 +1823,7 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
}

/* First check for a named mode */
- for (i = 0; i < ARRAY_SIZE(drm_named_modes_whitelist); i++) {
+ for (i = 0; mode_end && i < ARRAY_SIZE(drm_named_modes_whitelist); i++) {
ret = str_has_prefix(name, drm_named_modes_whitelist[i]);
if (ret == mode_end) {
if (refresh_ptr)
--
2.25.1