Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755867AbbLGMd4 (ORCPT ); Mon, 7 Dec 2015 07:33:56 -0500 Received: from mail-wm0-f49.google.com ([74.125.82.49]:33814 "EHLO mail-wm0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753450AbbLGMdz (ORCPT ); Mon, 7 Dec 2015 07:33:55 -0500 From: LABBE Corentin To: airlied@linux.ie Cc: LABBE Corentin , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm: modes: fix DRM modes analysis regression Date: Mon, 7 Dec 2015 13:33:45 +0100 Message-Id: <1449491626-5894-1-git-send-email-clabbe.montjoie@gmail.com> X-Mailer: git-send-email 2.4.10 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3477 Lines: 114 My latest commit introduce some case where a valid mode, could be rejected. simple_strtox functions stop at first non-digit character, but kstrtox not. So args like "video=HDMI-A-1:720x480-16@60" will be reject when checking 16@. The proper solution is to store digits in a specific buffer. Fixes: 52157a4ca396 ("drm: modes: replace simple_strtoul by kstrtouint") Reported-by: Kuninori Morimoto Signed-off-by: LABBE Corentin --- drivers/gpu/drm/drm_modes.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index bde9b29..3b5e9a5 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -1225,13 +1225,14 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option, struct drm_cmdline_mode *mode) { const char *name; - unsigned int namelen; + unsigned int namelen, digit_i; bool res_specified = false, bpp_specified = false, refresh_specified = false; unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0; bool yres_specified = false, cvt = false, rb = false; bool interlace = false, margins = false, was_digit = false; int i, err; enum drm_connector_force force = DRM_FORCE_UNSPECIFIED; + char *digits; #ifdef CONFIG_FB if (!mode_option) @@ -1245,42 +1246,53 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option, name = mode_option; namelen = strlen(name); + + digits = kzalloc(namelen, GFP_KERNEL); + if (!digits) + return false; + /* The last character must be the last 0 */ + digit_i = namelen; + for (i = namelen-1; i >= 0; i--) { switch (name[i]) { case '@': if (!refresh_specified && !bpp_specified && !yres_specified && !cvt && !rb && was_digit) { - err = kstrtouint(&name[i + 1], 10, &refresh); + err = kstrtouint(&digits[digit_i], 10, &refresh); if (err) return false; refresh_specified = true; was_digit = false; + digit_i = namelen; } else goto done; break; case '-': if (!bpp_specified && !yres_specified && !cvt && !rb && was_digit) { - err = kstrtouint(&name[i + 1], 10, &bpp); + err = kstrtouint(&digits[digit_i], 10, &bpp); if (err) return false; bpp_specified = true; was_digit = false; + digit_i = namelen; } else goto done; break; case 'x': if (!yres_specified && was_digit) { - err = kstrtouint(&name[i + 1], 10, &yres); + err = kstrtouint(&digits[digit_i], 10, &yres); if (err) return false; yres_specified = true; was_digit = false; + digit_i = namelen; } else goto done; break; case '0' ... '9': was_digit = true; + digits[--digit_i] = name[i]; break; case 'M': if (yres_specified || cvt || was_digit) @@ -1349,6 +1361,7 @@ done: "parse error at position %i in video mode '%s'\n", i, name); mode->specified = false; + kfree(digits); return false; } @@ -1373,6 +1386,7 @@ done: mode->margins = margins; mode->force = force; + kfree(digits); return true; } EXPORT_SYMBOL(drm_mode_parse_command_line_for_connector); -- 2.4.10 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/