linux-kernel - [PATCH] toshiba_acpi: Fix regression caused by backlight extra check code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1415073514-12555-1-git-send-email-coproscefalo@gmail.com>
Date:	Mon,  3 Nov 2014 20:58:34 -0700
From:	Azael Avalos <coproscefalo@...il.com>
To:	Darren Hart <dvhart@...radead.org>,
	platform-driver-x86@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:	Nuno Lopes <nunoplopes@...o.pt>,
	Azael Avalos <coproscefalo@...il.com>
Subject: [PATCH] toshiba_acpi: Fix regression caused by backlight extra  check code

Bug 86521 uncovered that some TOS6208 devices also return
non zero values on a write call to the backlight method,
thus getting caught and bailed out by the extra check code.

This patch makes sure that the extra check is being done
on a TOS1900 device and then make the check for the broken
backlight code.

Signed-off-by: Azael Avalos <coproscefalo@...il.com>
---
 drivers/platform/x86/toshiba_acpi.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index ef3a190..e3fed12 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -944,9 +944,13 @@ static int set_lcd_brightness(struct toshiba_acpi_dev *dev, int value)
 	/* Extra check for "incomplete" backlight method, where the AML code
 	 * doesn't check for HCI_SET or HCI_GET and returns TOS_SUCCESS,
 	 * the actual brightness, and in some cases the max brightness.
+	 * Use the SPFC method as an indicator that we're on a TOS1900 device,
+	 * otherwise some TOS6208 devices might get bailed out, see bug 86521
 	 */
-	if (out[2] > 0  || out[3] == 0xE000)
-		return -ENODEV;
+	if (acpi_has_method(dev->acpi_dev->handle, "SPFC")) {
+		if (out[2] > 0  || out[3] == 0xE000)
+			return -ENODEV;
+	}
 
 	return out[0] == TOS_SUCCESS ? 0 : -EIO;
 }
-- 
2.1.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/