[tip: x86/urgent] x86/microcode/AMD: Fix __apply_microcode_amd()'s return value

From: tip-bot2 for Boris Ostrovsky
Date: Fri Mar 28 2025 - 08:29:52 EST


The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: 31ab12df723543047c3fc19cb8f8c4498ec6267f
Gitweb: https://git.kernel.org/tip/31ab12df723543047c3fc19cb8f8c4498ec6267f
Author: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
AuthorDate: Thu, 27 Mar 2025 19:05:02 -04:00
Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Fri, 28 Mar 2025 12:49:02 +01:00

x86/microcode/AMD: Fix __apply_microcode_amd()'s return value

When verify_sha256_digest() fails, __apply_microcode_amd() should propagate
the failure by returning false (and not -1 which is promoted to true).

Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches")
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20250327230503.1850368-2-boris.ostrovsky@xxxxxxxxxx
---
arch/x86/kernel/cpu/microcode/amd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 138689b..b61028c 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -600,7 +600,7 @@ static bool __apply_microcode_amd(struct microcode_amd *mc, u32 *cur_rev,
unsigned long p_addr = (unsigned long)&mc->hdr.data_code;

if (!verify_sha256_digest(mc->hdr.patch_id, *cur_rev, (const u8 *)p_addr, psize))
- return -1;
+ return false;

native_wrmsrl(MSR_AMD64_PATCH_LOADER, p_addr);