From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (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 4836222F14C for ; Sun, 12 Oct 2025 20:39:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760301553; cv=none; b=uHi5d1UWrKjZ1jONKm2cAm8ysPzCorNO9EWsLm/sWZEiW7M26X0fJHReqIbtN9i+0n7BgSBBma9PdnmgH75N0MbX4N1jy9VjS6hqA6FYo8MGkmaWZbCXl7exhgKX+BoKWYMPa4kW9hrxcmlqa+bALbBZr/RBxrqQ8AIjTQrYIB4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760301553; c=relaxed/simple; bh=YIkTgYn9i2yw0iFaIALqYXIa9CMh1bynZaoWnsC+ihU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=IY+o3omlIkIHkxjcLs4KWzWpFS+NTG3DzNgDHrlYcUUsquvt8Qm6Oclgf0TzrUJExGcRrgmmmNFuJ+S5gYNg3/IE5fkj+NmyfUyL+s/h92Cjx68MiZpDzMFifTGbdEfJI72HxmtTbtBgm8L59WY88jj1vXWLwR8Lfq9AbGEmdRg= 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=ve1Cgubv; arc=none smtp.client-ip=91.218.175.185 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="ve1Cgubv" 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=1760301538; 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=FKhJ/WufXxLbU2grf7XLNEYhgrmN020loyUIXPWxv7U=; b=ve1Cgubv0YcbugdHFD/N9LGuipVUBqST1XmwsuU84PKVu2uM3x+m1bkJTcWy2AAarJi8+l c7hO7tTAUiGx2wGD4AH7FzxgTuboVUdpgh7uNLpfzF6T5/ZIpDTGqrojsT0uGVSiGDBRvD JCcCTaLZvjt7DEBEcWZn77cEA2mT55U= From: Thorsten Blum To: David Howells , Lukas Wunner , Ignat Korchagin , Herbert Xu , "David S. Miller" , Vivek Goyal Cc: Thorsten Blum , stable@vger.kernel.org, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/2] crypto: asymmetric_keys - prevent overflow in asymmetric_key_generate_id Date: Sun, 12 Oct 2025 22:38:40 +0200 Message-ID: <20251012203841.60230-1-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Use check_add_overflow() to guard against a potential integer overflow when adding the binary blob lengths in asymmetric_key_generate_id() and return -EOVERFLOW accordingly. This prevents a possible buffer overflow when copying data from potentially malicious X.509 fields that can be arbitrarily large, such as ASN.1 INTEGER serial numbers, issuer names, etc. Also use struct_size() to calculate the number of bytes to allocate for the new asymmetric key id. Cc: stable@vger.kernel.org Fixes: 7901c1a8effb ("KEYS: Implement binary asymmetric key ID handling") Signed-off-by: Thorsten Blum --- Changes in v2: - Use check_add_overflow() and error out as suggested by Lukas - Update patch description - Add Fixes: tag and @stable for backporting - Link to v1: https://lore.kernel.org/lkml/20251007185220.234611-2-thorsten.blum@linux.dev/ --- crypto/asymmetric_keys/asymmetric_type.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c index ba2d9d1ea235..bd96f799757d 100644 --- a/crypto/asymmetric_keys/asymmetric_type.c +++ b/crypto/asymmetric_keys/asymmetric_type.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -141,12 +142,14 @@ struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1, size_t len_2) { struct asymmetric_key_id *kid; + size_t len; - kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2, - GFP_KERNEL); + if (check_add_overflow(len_1, len_2, &len)) + return ERR_PTR(-EOVERFLOW); + kid = kmalloc(struct_size(kid, data, len), GFP_KERNEL); if (!kid) return ERR_PTR(-ENOMEM); - kid->len = len_1 + len_2; + kid->len = len; memcpy(kid->data, val_1, len_1); memcpy(kid->data + len_1, val_2, len_2); return kid; -- 2.51.0