linux-kernel - [PATCH 01/13] x86/microcode/intel: Check if microcode was found before applying

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

Date:	Tue, 24 Feb 2015 11:37:00 +0100
From:	Borislav Petkov <bp@...en8.de>
To:	X86 ML <x86@...nel.org>
Cc:	LKML <linux-kernel@...r.kernel.org>,
	Quentin Casasnovas <quentin.casasnovas@...cle.com>
Subject: [PATCH 01/13] x86/microcode/intel: Check if microcode was found before applying

From: Borislav Petkov <bp@...e.de>

We should check the return value of the routines fishing out the proper
microcode and not try to apply if we haven't found a suitable blob.

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/microcode/intel_early.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/microcode/intel_early.c b/arch/x86/kernel/cpu/microcode/intel_early.c
index 420eb933189c..b3cb1568cd9a 100644
--- a/arch/x86/kernel/cpu/microcode/intel_early.c
+++ b/arch/x86/kernel/cpu/microcode/intel_early.c
@@ -729,9 +729,10 @@ _load_ucode_intel_bsp(struct mc_saved_data *mc_saved_data,
 
 	ret = load_microcode(mc_saved_data, mc_saved_in_initrd,
 			     initrd_start_early, uci);
+	if (ret != UCODE_OK)
+		return;
 
-	if (ret == UCODE_OK)
-		apply_microcode_early(uci, true);
+	apply_microcode_early(uci, true);
 }
 
 void __init
@@ -771,6 +772,7 @@ void load_ucode_intel_ap(void)
 	struct ucode_cpu_info uci;
 	unsigned long *mc_saved_in_initrd_p;
 	unsigned long initrd_start_addr;
+	enum ucode_state ret;
 #ifdef CONFIG_X86_32
 	unsigned long *initrd_start_p;
 
@@ -793,8 +795,12 @@ void load_ucode_intel_ap(void)
 		return;
 
 	collect_cpu_info_early(&uci);
-	load_microcode(mc_saved_data_p, mc_saved_in_initrd_p,
-		       initrd_start_addr, &uci);
+	ret = load_microcode(mc_saved_data_p, mc_saved_in_initrd_p,
+			     initrd_start_addr, &uci);
+
+	if (ret != UCODE_OK)
+		return;
+
 	apply_microcode_early(&uci, true);
 }
 
-- 
2.2.0.33.gc18b867

--
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/