From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9A0E5581229 for ; Fri, 11 Sep 2026 19:50:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156250; cv=none; b=FCUJpR4VuAZCflMGAdcXbqbZkGWUDQOZrgRm0iTaMkh0E1ZmSBPwW31yhuJW7ZPUShPnhW8/UCNJvLeNQlp5JAw81jwnNdFilTPXO4NW8lMmJAjq3wuSjz5LxejGF+9Tz6Yfv3FfFX2OSdjA32pBj5o7eLMW2gtdswomWlov7ZE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156250; c=relaxed/simple; bh=p120lklY/dbTtMmPOGxjKAGvxj3HUlS/NyLZWD3+ho8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=rf8+5iyYf2tqUKj1nysxN1+UkWbJPIpuUli9/NJm+hdzngW4l/5+touOBWzDo/VwNQZwZOU3VNOBKXJUiAWbLo9eWpYXQ+3AyzKUZ/1GesHABydccmym2+uc9VoE723FN4xx6MPDCciMhBYxT8toP/2BYWP5JGML25ETPevhbCY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WcxWOEOw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="WcxWOEOw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E937F1F00893; Fri, 11 Sep 2026 19:50:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156236; bh=Zt3nvW8o4mFONQ/jZv2nsyAGmrEaWOZY6UB3T8QRdYE=; h=From:To:Cc:Subject:Date:Reply-To; b=WcxWOEOwfb3f/i64KkZZOPsXu4bM1qTXH3nnHvHUGbnLHbRn7WhOOs5Pc6cJ8fwOK Mza8NAcfTYm83KY9vCsxVhn0B4vsDhAn+u/++lHz8Dq1k+oCjsBxRH+jzSOyEgqFXN /hPadaoif9YUb2rk4+bkfh+tTbC34FaR8g9eW1fs= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89450: iommu/tegra241-cmdqv: Reject a vSID wider than the SID_MATCH field Date: Fri, 11 Sep 2026 21:42:19 +0200 Message-ID: <2026091158-CVE-2026-89450-db6c@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2731; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=dwbJ9WQwq5M82sPyR0RzIYs7CL/WSktT5Ce5a9FNqE0=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIr2KElI6fvFw+jXVzVdxEzn97MWPfKfXDCpfl5vVb HOulCrqiGVhEGRikBVTZPmyjefo/opDil6Gtqdh5rAygQxh4OIUgIn8WsAwV/x10wXrcrGlu+Ml vkZ17ltyZ5WxDMOCM/vrFwj4BEfN41pl8ObSM5s2Bq4XAA== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: iommu/tegra241-cmdqv: Reject a vSID wider than the SID_MATCH field tegra241_vintf_init_vsid() programs the guest-provided vSID into SID_MATCH, whose VIRT_SID field spans bits [20:1] with bit 0 as the match-enable flag. The HW therefore matches only a 20-bit Stream ID. The bound check rejects only virt_sid > UINT_MAX, which admits a value far wider than the field. The write "virt_sid << 1 | 0x1" then drops every bit above 20: a virt_sid of 0x80000000 lands as SID_MATCH = 0x1, a valid match on vSID 0, so the entry aliases the wrong Stream ID. Because vdev->virt_id is guest-controlled, a VMM can trigger it. Validate virt_sid against the field width with FIELD_MAX(), and program the register with FIELD_PREP() so the value and the field stay consistent. The Linux kernel CVE team has assigned CVE-2026-89450 to this issue. Affected and fixed versions =========================== Issue introduced in 6.17 with commit 4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7 and fixed in 6.18.50 with commit d903d99ffd22b0180bd745a43f221c21bcdd8d7c Issue introduced in 6.17 with commit 4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7 and fixed in 7.2.4 with commit 445204550f894ca325ac80a21e3df177ad073798 Issue introduced in 6.17 with commit 4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7 and fixed in 7.3-rc1 with commit 4379610c79bd88ddbea10e7f6c21e16d4b338c6b 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-2026-89450 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: drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c 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/d903d99ffd22b0180bd745a43f221c21bcdd8d7c https://git.kernel.org/stable/c/445204550f894ca325ac80a21e3df177ad073798 https://git.kernel.org/stable/c/4379610c79bd88ddbea10e7f6c21e16d4b338c6b