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 A7AD240DFD4; Mon, 4 May 2026 14:08:31 +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=1777903711; cv=none; b=WTV0fX3kjFLc7ekCHk6Wc9zZov1o/G3YeeSLAPIOpfFNxlfLS79yPmbjwvnxgVX1eFOjm6HtNANgGVIrdmdhDSAMF5EGJWArOlHf7EZVdWynijamToRO8jerhIYQ2GWlqdvx+gylCVaFxZx1lSB2uCu3REGm3QxcZs4zSkCyDnE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777903711; c=relaxed/simple; bh=Ehi6DzPATBas1TWud/jYamJ7jKk2Qg9awB0Nz43fKKg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ewEE7HbO7FNfAA6zOpMNd/F1cl4i6uayPLjGqDut0P4Bu2Uv2xnD2U/N5s2JJOYkshgvI6uiCmtkf7dp4i7AN2r3/pjvhZhCvE8D7PK7sV4qFEbX9Xrnpa3J9SYLL3ydA7tl19mqs4kPsmgriY9xZ7lfTbqqaCr+CTVqXqY72MM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=rIkTf7CR; 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="rIkTf7CR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E5CFC2BCB8; Mon, 4 May 2026 14:08:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1777903711; bh=Ehi6DzPATBas1TWud/jYamJ7jKk2Qg9awB0Nz43fKKg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rIkTf7CRJnsxAXWaHWjq6Y1ScUNgM+qvnZkOFD0ZAanJgpurRTfhZ8Bk/tXk8/vdB qo4Gj4oY3Q8Ryf4BbhESeDTtpci06u2hi05/3kvQG8zACgiezeNJ59rC0fb69X9brm Otrs2s6dUCf+u+MwTatGWUF/ob2naQayVq2KCQLY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Prasanna Kumar T S M , Nipun Gupta , Alex Williamson , Nikhil Agarwal , Alex Williamson Subject: [PATCH 6.18 033/275] vfio/cdx: Fix NULL pointer dereference in interrupt trigger path Date: Mon, 4 May 2026 15:49:33 +0200 Message-ID: <20260504135144.169278741@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260504135142.929052779@linuxfoundation.org> References: <20260504135142.929052779@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Prasanna Kumar T S M commit 5ea5880764cbb164afb17a62e76ca75dc371409d upstream. Add validation to ensure MSI is configured before accessing cdx_irqs array in vfio_cdx_set_msi_trigger(). Without this check, userspace can trigger a NULL pointer dereference by calling VFIO_DEVICE_SET_IRQS with VFIO_IRQ_SET_DATA_BOOL or VFIO_IRQ_SET_DATA_NONE flags before ever setting up interrupts via VFIO_IRQ_SET_DATA_EVENTFD. The vfio_cdx_msi_enable() function allocates the cdx_irqs array and sets config_msi to 1 only when called through the EVENTFD path. The trigger loop (for DATA_BOOL/DATA_NONE) assumed this had already been done, but there was no enforcement of this call ordering. This matches the protection used in the PCI VFIO driver where vfio_pci_set_msi_trigger() checks irq_is() before the trigger loop. Fixes: 848e447e000c ("vfio/cdx: add interrupt support") Cc: stable@vger.kernel.org Signed-off-by: Prasanna Kumar T S M Acked-by: Nipun Gupta Signed-off-by: Alex Williamson Acked-by: Nikhil Agarwal Link: https://lore.kernel.org/r/20260417202800.88287-2-alex.williamson@nvidia.com Signed-off-by: Alex Williamson Signed-off-by: Greg Kroah-Hartman --- drivers/vfio/cdx/intr.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/vfio/cdx/intr.c +++ b/drivers/vfio/cdx/intr.c @@ -177,6 +177,10 @@ static int vfio_cdx_set_msi_trigger(stru return ret; } + /* Ensure MSI is configured before accessing cdx_irqs */ + if (!vdev->config_msi) + return -EINVAL; + for (i = start; i < start + count; i++) { if (!vdev->cdx_irqs[i].trigger) continue;