From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-172.mta1.migadu.com (out-172.mta1.migadu.com [95.215.58.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 35B32473C6A for ; Thu, 23 Jul 2026 13:37:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784813861; cv=none; b=nCgbXdfZzRmY71YydLwAG8oAXGn3WM358jYtrYXEyLGWqOrlgZY4cwAKb0CDVaOiYRcQGxzyS4TGApzribtpJmOnc1qlxdstn4+wxeSYxpKCRwlH354MB5fTJpPmtVgbZQUKAM3pd1hoUaH418bd1/vCg28QclVbAHHVHddehk0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784813861; c=relaxed/simple; bh=EoOsFO6jmbt6FHNb6fzSNaYX7wdEhpIgEPWusKpqvvI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=GdZbPidyDZPDOoz+OI13Og7W1vxY7hGtz5JHXQn56BZRfJql2KXTGakQ+blrWTFQ/fUD+Uc6hZR/CG4c4FBCYJkWSvlsURIH69NlQ95f/WwdC1L1DCXhjUBZx77F/mNSrU31DdIQOr4pyYll/6KXIiixdEKjNUoo0279j5+imgc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=u8vCzSXm; arc=none smtp.client-ip=95.215.58.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="u8vCzSXm" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1784813846; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=bQbw3ijXJXpM7DdNzVKHQkDlJ5kgWeHFVGQBkZwPxBU=; b=u8vCzSXmmwqDXJC1ESue5tKE48p86pztSM5wJTSvwcqsNdK/NbtAneamPxGNJCA87Icl0Y YSIVN1CPS2Lxy53jEhK17RnwdRHYVmFH80i9QsUiIDTqSh9bUYXiJF7qSMKLZrtChbeUZ6 tUl7qjncrJH4VGFTS86qIeEkREMfFxE= From: Thorsten Blum To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" Cc: Thorsten Blum , linux-kernel@vger.kernel.org Subject: [PATCH v2] x86/purgatory: Return bool from verify_sha256_digest() Date: Thu, 23 Jul 2026 15:36:34 +0200 Message-ID: <20260723133634.161598-3-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1852; i=thorsten.blum@linux.dev; h=from:subject; bh=EoOsFO6jmbt6FHNb6fzSNaYX7wdEhpIgEPWusKpqvvI=; b=owGbwMvMwCUWt7pQ4caZUj3G02pJDFlJEo9tSl8XpVTN7lnzkK+eeznfNp042/KWU8dWpAdxN 9zNWjSro5SFQYyLQVZMkeXBrB8zfEtrKjeZROyEmcPKBDKEgYtTACbSos3wPz2/1jtH31wk2lib qTGj8jXDDa6UWcYPvivUyKjvsuTmZvifYFMV159n7vXrt6DM9RdcLYtOpvzLZZe5Uzjb6NLJhWc 5AQ== X-Developer-Key: i=thorsten.blum@linux.dev; a=openpgp; fpr=1D60735E8AEF3BE473B69D84733678FD8DFEEAD4 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Change the function's return type from int to bool and return the result of memcmp() directly to simplify the code. While at it, cast ->start to const u8 * to better match the expected type. Also inline the verify_sha256_digest() check and remove the redundant local ret variable in purgatory(). Signed-off-by: Thorsten Blum --- Changes in v2: - Return !memcmp() as suggested by Ingo - v1: https://lore.kernel.org/r/20260722162245.156368-2-thorsten.blum@linux.dev/ --- arch/x86/purgatory/purgatory.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c index 655139dd0532..45836aca1a4b 100644 --- a/arch/x86/purgatory/purgatory.c +++ b/arch/x86/purgatory/purgatory.c @@ -21,7 +21,7 @@ u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(".kexec-purgatory"); struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(".kexec-purgatory"); -static int verify_sha256_digest(void) +static bool verify_sha256_digest(void) { struct kexec_sha_region *ptr, *end; u8 digest[SHA256_DIGEST_SIZE]; @@ -31,22 +31,16 @@ static int verify_sha256_digest(void) end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions); for (ptr = purgatory_sha_regions; ptr < end; ptr++) - sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len); + sha256_update(&sctx, (const u8 *)(ptr->start), ptr->len); sha256_final(&sctx, digest); - if (memcmp(digest, purgatory_sha256_digest, sizeof(digest))) - return 1; - - return 0; + return !memcmp(digest, purgatory_sha256_digest, sizeof(digest)); } void purgatory(void) { - int ret; - - ret = verify_sha256_digest(); - if (ret) { + if (!verify_sha256_digest()) { /* loop forever */ for (;;) ;