{"id":2226108,"url":"http://patchwork.ozlabs.org/api/patches/2226108/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260422092910.444997-3-kraxel@redhat.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260422092910.444997-3-kraxel@redhat.com>","list_archive_url":null,"date":"2026-04-22T09:29:05","name":"[2/6] hw/uefi: verify pio_xfer_offset before calculating buffer checksum","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"acc7c565ed4ca650ac12e2465658642b38c49b46","submitter":{"id":589,"url":"http://patchwork.ozlabs.org/api/people/589/?format=json","name":"Gerd Hoffmann","email":"kraxel@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260422092910.444997-3-kraxel@redhat.com/mbox/","series":[{"id":500953,"url":"http://patchwork.ozlabs.org/api/series/500953/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=500953","date":"2026-04-22T09:29:03","name":"hw/uefi: a batch of security fixes","version":1,"mbox":"http://patchwork.ozlabs.org/series/500953/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2226108/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2226108/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=AutiqrrH;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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Wed, 22 Apr 2026 05:29:22 -0400","from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com\n (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by\n relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3,\n cipher=TLS_AES_256_GCM_SHA384) id us-mta-400-XpRkL6RqNv6DjlFUpPZfbQ-1; Wed,\n 22 Apr 2026 05:29:16 -0400","from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com\n (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111])\n (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest\n SHA256)\n (No client certificate requested)\n by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS\n id 50CC3180036E; Wed, 22 Apr 2026 09:29:15 +0000 (UTC)","from sirius.home.kraxel.org (unknown [10.44.48.53])\n by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with\n ESMTPS\n id D784E180045E; Wed, 22 Apr 2026 09:29:14 +0000 (UTC)","by sirius.home.kraxel.org (Postfix, from userid 1000)\n id 3BE4C1801027; Wed, 22 Apr 2026 11:29:10 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1776850160;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:cc:mime-version:mime-version:\n content-transfer-encoding:content-transfer-encoding:\n in-reply-to:in-reply-to:references:references;\n bh=iAIhx+eknpPypj9xxQeslr/Qb9BEK/gelulIMZV9Ehc=;\n b=AutiqrrH9LJ/ZzRGkecA4SGpARz/jXuKJ2Fqi4NCGUHVHANa9AZ2mWrvhdvcirUg3jT+hW\n gcaTuvwimP2m7CceBEcdI7TJcqyoWUcD82Dq4ysZJOWNrqPaS8cSe77v8l8DOEg3MxbPX+\n F9amVkJv8NcKKqCj7FoAwg1REk63QX0=","X-MC-Unique":"XpRkL6RqNv6DjlFUpPZfbQ-1","X-Mimecast-MFC-AGG-ID":"XpRkL6RqNv6DjlFUpPZfbQ_1776850155","From":"Gerd Hoffmann ","To":"qemu-devel@nongnu.org","Cc":"Gerd Hoffmann ,\n Katherine Leaver ","Subject":"[PATCH 2/6] hw/uefi: verify pio_xfer_offset before calculating buffer\n checksum","Date":"Wed, 22 Apr 2026 11:29:05 +0200","Message-ID":"<20260422092910.444997-3-kraxel@redhat.com>","In-Reply-To":"<20260422092910.444997-1-kraxel@redhat.com>","References":"<20260422092910.444997-1-kraxel@redhat.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Scanned-By":"MIMEDefang 3.4.1 on 10.30.177.111","Received-SPF":"pass client-ip=170.10.133.124; envelope-from=kraxel@redhat.com;\n helo=us-smtp-delivery-124.mimecast.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001,\n DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_PASS=-0.001,\n SPF_PASS=-0.001 autolearn=ham autolearn_force=no","X-Spam_action":"no action","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"Without that it is possible to do trigger OOB reads by first\nadvancing offset, then making the buffer smaller, finally\nasking for a checksum.\n\nFixes: CVE-2026-41436\nFixes: 90ca4e03c27d (\"hw/uefi: add var-service-core.c\")\nReported-by: Katherine Leaver \nSigned-off-by: Gerd Hoffmann \n---\n hw/uefi/var-service-core.c | 4 ++++\n 1 file changed, 4 insertions(+)","diff":"diff --git a/hw/uefi/var-service-core.c b/hw/uefi/var-service-core.c\nindex 68d7594c0dd6..828d76007318 100644\n--- a/hw/uefi/var-service-core.c\n+++ b/hw/uefi/var-service-core.c\n@@ -235,6 +235,10 @@ static uint64_t uefi_vars_read(void *opaque, hwaddr addr, unsigned size)\n uv->pio_xfer_offset += size;\n break;\n case UEFI_VARS_REG_PIO_BUFFER_CRC32C:\n+ if (uv->pio_xfer_offset > uv->buf_size) {\n+ retval = 0;\n+ break;\n+ }\n retval = crc32c(0xffffffff, uv->pio_xfer_buffer, uv->pio_xfer_offset);\n break;\n case UEFI_VARS_REG_FLAGS:\n","prefixes":["2/6"]}