diff options
author | Borislav Petkov <bp@suse.de> | 2022-12-19 22:06:56 +0100 |
---|---|---|
committer | Borislav Petkov (AMD) <bp@alien8.de> | 2022-12-26 06:41:05 +0100 |
commit | ba73e369b706a853cdafa60570854fecec9f9fdd (patch) | |
tree | df0719b9f157101112b315aaeb636dc11e10c366 /arch/x86/kernel/cpu/microcode | |
parent | 61de9b7036f26448a1916291c456f62dd6bf07ea (diff) |
x86/microcode/AMD: Handle multiple glued containers properly
It can happen that - especially during testing - the microcode
blobs of all families are all glued together in the initrd. The
current code doesn't check whether the current container matched
a microcode patch and continues to the next one, which leads to
save_microcode_in_initrd_amd() to look at the next and thus wrong one:
microcode: parse_container: ucode: 0xffff88807e9d9082
microcode: verify_patch: buf: 0xffff88807e9d90ce, buf_size: 26428
microcode: verify_patch: proc_id: 0x8082, patch_fam: 0x17, this family: 0x17
microcode: verify_patch: buf: 0xffff88807e9d9d56, buf_size: 23220
microcode: verify_patch: proc_id: 0x8012, patch_fam: 0x17, this family: 0x17
microcode: parse_container: MATCH: eq_id: 0x8012, patch proc_rev_id: 0x8012
<-- matching patch found
microcode: verify_patch: buf: 0xffff88807e9da9de, buf_size: 20012
microcode: verify_patch: proc_id: 0x8310, patch_fam: 0x17, this family: 0x17
microcode: verify_patch: buf: 0xffff88807e9db666, buf_size: 16804
microcode: Invalid type field (0x414d44) in container file section header.
microcode: Patch section fail
<-- checking chokes on the microcode magic value of the next container.
microcode: parse_container: saving container 0xffff88807e9d9082
microcode: save_microcode_in_initrd_amd: scanned containers, data: 0xffff88807e9d9082, size: 9700a
and now if there's a next (and last container) it'll use that in
save_microcode_in_initrd_amd() and not find a proper patch, ofc.
Fix that by moving the out: label up, before the desc->mc check which
jots down the pointer of the matching patch and is used to signal to the
caller that it has found a matching patch in the current container.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20221219210656.5140-2-bp@alien8.de
Diffstat (limited to 'arch/x86/kernel/cpu/microcode')
-rw-r--r-- | arch/x86/kernel/cpu/microcode/amd.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 339c9666c8bc..d144f918a896 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -330,8 +330,9 @@ static size_t parse_container(u8 *ucode, size_t size, struct cont_desc *desc) ret = verify_patch(x86_family(desc->cpuid_1_eax), buf, size, &patch_size, true); if (ret < 0) { /* - * Patch verification failed, skip to the next - * container, if there's one: + * Patch verification failed, skip to the next container, if + * there is one. Before exit, check whether that container has + * found a patch already. If so, use it. */ goto out; } else if (ret > 0) { @@ -350,6 +351,7 @@ skip: size -= patch_size + SECTION_HDR_SIZE; } +out: /* * If we have found a patch (desc->mc), it means we're looking at the * container which has a patch for this CPU so return 0 to mean, @ucode @@ -364,7 +366,6 @@ skip: return 0; } -out: return orig_size - size; } |