x86/microcode/AMD: Extend the SHA check to Zen5, block loading of any unreleased...
authorBorislav Petkov (AMD) <bp@alien8.de>
Thu, 10 Apr 2025 11:42:22 +0000 (13:42 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 25 Apr 2025 08:47:55 +0000 (10:47 +0200)
commit 805b743fc163f1abef7ce1bea8eca8dfab5b685b upstream.

All Zen5 machines out there should get BIOS updates which update to the
correct microcode patches addressing the microcode signature issue.
However, silly people carve out random microcode blobs from BIOS
packages and think are doing other people a service this way...

Block loading of any unreleased standalone Zen5 microcode patches.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Cc: Nikolay Borisov <nik.borisov@suse.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20250410114222.32523-1-bp@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/cpu/microcode/amd.c

index 5cd735728fa02807164a4d11f1fa1b74eace7e25..093d3ca43c4674f994b8d7ab58546fb7c6dbab39 100644 (file)
@@ -199,6 +199,12 @@ static bool need_sha_check(u32 cur_rev)
        case 0xa70c0: return cur_rev <= 0xa70C009; break;
        case 0xaa001: return cur_rev <= 0xaa00116; break;
        case 0xaa002: return cur_rev <= 0xaa00218; break;
+       case 0xb0021: return cur_rev <= 0xb002146; break;
+       case 0xb1010: return cur_rev <= 0xb101046; break;
+       case 0xb2040: return cur_rev <= 0xb204031; break;
+       case 0xb4040: return cur_rev <= 0xb404031; break;
+       case 0xb6000: return cur_rev <= 0xb600031; break;
+       case 0xb7000: return cur_rev <= 0xb700031; break;
        default: break;
        }
 
@@ -214,8 +220,7 @@ static bool verify_sha256_digest(u32 patch_id, u32 cur_rev, const u8 *data, unsi
        struct sha256_state s;
        int i;
 
-       if (x86_family(bsp_cpuid_1_eax) < 0x17 ||
-           x86_family(bsp_cpuid_1_eax) > 0x19)
+       if (x86_family(bsp_cpuid_1_eax) < 0x17)
                return true;
 
        if (!need_sha_check(cur_rev))