From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 5C5B8146D6C for ; Tue, 21 May 2024 15:40:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716306002; cv=none; b=SrOsOEKrWcdgsl3XONDjPjQm8jxvgFVsU2hwFIsQHi7Mmo+p/eA34J6iviSemyl85hAdACdU4yiWr4gxgAUx2xxRtEcCRuJ8nZk4vZa9qVKtAk9PdVTrW24+RJDO81qSjNK3smK418zD/RqU3kwAQ1RmeOpG6iUFbcIWranWZvQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716306002; c=relaxed/simple; bh=ZRoK15xs8iOkZa6I/DwBq9F3eztAd1r3biNG8kNIcqU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=jENbixhhldf3koU18+3SykGYUJQhb1Sw4xAYBY+qvwvXTX21OA13tzbieoKYESafbehdcyIK7Z00VW9/JyWSSi+7VSLqAaetEQx2Y8ztIXyKbTg9jYUKdYP9X3SxVTbsP3Do3dYKfK/N8Gv2bhOGg1UqT+Q1g6W/+7qATD/tM8I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tPusdFFd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="tPusdFFd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6290C2BD11; Tue, 21 May 2024 15:40:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1716306002; bh=ZRoK15xs8iOkZa6I/DwBq9F3eztAd1r3biNG8kNIcqU=; h=From:To:Cc:Subject:Date:Reply-to:From; b=tPusdFFdqODCJeihqZiqALfgYhK6DLyip/ys2DW3RuC4lIUeX4wVRNqM/Jr4ZUoLo /E8HjUYVTOHJGiuoN3L3fdJSsNi8RkBHpmkaJ+T+7iuu/1n2MpdoBdTXgzO1aaF2lA jCisZ20rq7hWAS70qXg8FxE4JAYeHkP7v/9pdPzs= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2023-52874: x86/tdx: Zero out the missing RSI in TDX_HYPERCALL macro Date: Tue, 21 May 2024 17:32:50 +0200 Message-ID: <2024052121-CVE-2023-52874-2fda@gregkh> X-Mailer: git-send-email 2.45.1 Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reply-to: , X-Developer-Signature: v=1; a=openpgp-sha256; l=2664; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=ZRoK15xs8iOkZa6I/DwBq9F3eztAd1r3biNG8kNIcqU=; b=owGbwMvMwCRo6H6F97bub03G02pJDGk++zy/2myTqjFvCahZVLF7stMZX/NHAXpGLQJqr44IN WxinDG3I5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACbyaTfD/Jopr564iUzM3VoQ /SMn//wt+RWsMxnmCvI1/J42I0t18nz+jqXNHmK/lgjvBwA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit Description =========== In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Zero out the missing RSI in TDX_HYPERCALL macro In the TDX_HYPERCALL asm, after the TDCALL instruction returns from the untrusted VMM, the registers that the TDX guest shares to the VMM need to be cleared to avoid speculative execution of VMM-provided values. RSI is specified in the bitmap of those registers, but it is missing when zeroing out those registers in the current TDX_HYPERCALL. It was there when it was originally added in commit 752d13305c78 ("x86/tdx: Expand __tdx_hypercall() to handle more arguments"), but was later removed in commit 1e70c680375a ("x86/tdx: Do not corrupt frame-pointer in __tdx_hypercall()"), which was correct because %rsi is later restored in the "pop %rsi". However a later commit 7a3a401874be ("x86/tdx: Drop flags from __tdx_hypercall()") removed that "pop %rsi" but forgot to add the "xor %rsi, %rsi" back. Fix by adding it back. The Linux kernel CVE team has assigned CVE-2023-52874 to this issue. Affected and fixed versions =========================== Issue introduced in 6.4 with commit 7a3a401874be and fixed in 6.5.12 with commit 2191950d35d8 Issue introduced in 6.4 with commit 7a3a401874be and fixed in 6.6.2 with commit de4c5bacca4f Issue introduced in 6.4 with commit 7a3a401874be and fixed in 6.7 with commit 5d092b66119d Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2023-52874 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: arch/x86/coco/tdx/tdcall.S Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/2191950d35d8f81620ea8d4e04d983f664fe3a8a https://git.kernel.org/stable/c/de4c5bacca4f50233f1f791bec9eeb4dee1b14cd https://git.kernel.org/stable/c/5d092b66119d774853cc9308522620299048a662