From a40e7cf8f06b4e322ba902e4e9f6a6b0c2daa907 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Fri, 8 Mar 2013 12:43:32 -0800 Subject: [PATCH] dmi_scan: fix missing check for _DMI_ signature in smbios_present() Commit 9f9c9cbb6057 ("drivers/firmware/dmi_scan.c: fetch dmi version from SMBIOS if it exists") hoisted the check for "_DMI_" into dmi_scan_machine(), which means that we don't bother to check for "_DMI_" at offset 16 in an SMBIOS entry. smbios_present() may also call dmi_present() for an address where we found "_SM_", if it failed further validation. Check for "_DMI_" in smbios_present() before calling dmi_present(). [akpm@linux-foundation.org: fix build] Signed-off-by: Ben Hutchings Reported-by: Tim McGrath Tested-by: Tim Mcgrath Cc: Zhenzhong Duan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/firmware/dmi_scan.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index 982f1f5f5742..4cd392dbf115 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -442,7 +442,6 @@ static int __init dmi_present(const char __iomem *p) static int __init smbios_present(const char __iomem *p) { u8 buf[32]; - int offset = 0; memcpy_fromio(buf, p, 32); if ((buf[5] < 32) && dmi_checksum(buf, buf[5])) { @@ -461,9 +460,9 @@ static int __init smbios_present(const char __iomem *p) dmi_ver = 0x0206; break; } - offset = 16; + return memcmp(p + 16, "_DMI_", 5) || dmi_present(p + 16); } - return dmi_present(buf + offset); + return 1; } void __init dmi_scan_machine(void) -- 2.20.1