Path: csiph.com!aioe.org!bofh.it!news.nic.it!robomod From: Greg Kroah-Hartman Newsgroups: linux.kernel Subject: [PATCH 4.0 117/148] firmware: dmi_scan: Fix ordering of product_uuid Date: Wed, 03 Jun 2015 14:50:02 +0200 Message-ID: References: X-Original-To: linux-kernel@vger.kernel.org X-Mailer: git-send-email 2.4.2 User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 74 Organization: linux.* mail to news gateway X-Original-Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jean Delvare , Zhenzhong Duan , Ben Hutchings , Artem Savkov , Ivan Khoronzhuk , Matt Fleming X-Original-Date: Wed, 3 Jun 2015 21:09:47 +0900 X-Original-Message-ID: <20150603114210.474996729@linuxfoundation.org> X-Original-References: <20150603114205.337615117@linuxfoundation.org> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: aioe.org linux.kernel:1157547 4.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jean Delvare commit 5c1ac56b51b9d222ab202dec1ac2f4215346129d upstream. In function dmi_present(), dmi_walk_early() calls dmi_table(), which calls dmi_decode(), which ultimately calls dmi_save_uuid(). This last function makes a decision based on the value of global variable dmi_ver. The problem is that this variable is set right _after_ dmi_walk_early() returns. So dmi_save_uuid() always sees dmi_ver == 0 regardless of the actual version implemented. This causes /sys/class/dmi/id/product_uuid to always use the old ordering even on systems implementing DMI/SMBIOS 2.6 or later, which should use the new ordering. This is broken since kernel v3.8 for legacy DMI implementations and since kernel v3.10 for SMBIOS 2 implementations. SMBIOS 3 implementations with the 64-bit entry point are not affected. The first breakage does not matter much as in practice legacy DMI implementations are always for versions older than 2.6, which is when the UUID ordering changed. The second breakage is more problematic as it affects the vast majority of x86 systems manufactured since 2009. Signed-off-by: Jean Delvare Fixes: 9f9c9cbb6057 ("drivers/firmware/dmi_scan.c: fetch dmi version from SMBIOS if it exists") Fixes: 79bae42d51a5 ("dmi_scan: refactor dmi_scan_machine(), {smbios,dmi}_present()") Acked-by: Zhenzhong Duan Cc: Ben Hutchings Cc: Artem Savkov Cc: Ivan Khoronzhuk Cc: Matt Fleming Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/dmi_scan.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -499,18 +499,19 @@ static int __init dmi_present(const u8 * buf += 16; if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) { + if (smbios_ver) + dmi_ver = smbios_ver; + else + dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F); dmi_num = get_unaligned_le16(buf + 12); dmi_len = get_unaligned_le16(buf + 6); dmi_base = get_unaligned_le32(buf + 8); if (dmi_walk_early(dmi_decode) == 0) { if (smbios_ver) { - dmi_ver = smbios_ver; pr_info("SMBIOS %d.%d present.\n", dmi_ver >> 8, dmi_ver & 0xFF); } else { - dmi_ver = (buf[14] & 0xF0) << 4 | - (buf[14] & 0x0F); pr_info("Legacy DMI %d.%d present.\n", dmi_ver >> 8, dmi_ver & 0xFF); } -- 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/