From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E8E6B606D813 for ; Fri, 6 Nov 2026 12:02:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=hMqwliy1; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=XIW4+VP5 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=b32C5Yk9u4T7M0pDjYb1nHa0EfPn+C/TBJuye6XXKRU=; b=hMqwliy1mwSKf3 4+VUhOG7EynAwrDkD1Tn0KR3stWlO/AcVCLXwm5FmoCZ0p+OzYzmiORtipsvWbG/7DM5TBtlo1ueu QjNC01zbBFmdIaMyTAzOl/RB78e8FeRmumKLgfvR4RUZCG/BRGj5UWox+VTFfxSNUOw0F+UH56klD SJbFfT/7gIQQua5OoE5uVgbdVAuEkLcuKjDvf7f0tLZUaZ4yLTd8P9QBDGhmfddpmJnedbOclvv+U v+oyyBvnyMfA0V99oLjuFjr0bo0mekgM3FEraukscwpofL+bs41hSv562sl/LpUXYIdZ5/RPWf5DY R+jP0SjY98Q4mzkHcqKg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xPIeR-0000000CFMe-3s5G; Fri, 06 Nov 2026 12:02:35 +0000 Received: from out-7.mta0.migadu.com ([2001:41d0:1004:224b::7] helo=mta0.migadu.com) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xPIeQ-0000000CFLN-1GXC for linux-arm-kernel@lists.infradead.org; Fri, 06 Nov 2026 12:02:35 +0000 X-Envelope-To: linux-arm-kernel@lists.infradead.org DKIM-Signature: a=rsa-sha256; bh=q3JqZ19Rhc6bQOGntufhM8h8GdVro+mBU1Hah1TvlB4=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793966552; v=1; x=1794571352; b=XIW4+VP5VgX2Y4/JM5ow8B05ruRJMttgx7KgFpzCoF+yEJUG3wxEpRAolZbw9cbTcV8l0Bl9 HKRH/tDQeSiOA2Y1WDTB4jCHrl0E6Dr8OWisb/GWEcgYhfuCJunYczH/ScytjjxCPg9OeHzLgf9 8ARBFuoz/+nHasXcZA/WQs3k= X-Envelope-To: linux-arm-kernel@lists.infradead.org Received: by smtp.migadu.com with ESMTPS id a5ec145303592f44; Fri, 06 Nov 2026 12:02:32 +0000 X-Mizu-Trace-ID: a5ec145303592f44 X-Migadu-Flow: FLOW_OUT From: Fuad Tabba To: maz@kernel.org, tglx@kernel.org Cc: radu@rendec.net, lpieralisi@kernel.org, steven.price@arm.com, suzuki.poulose@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, will@kernel.org, tabba@google.com, stable@vger.kernel.org Subject: [PATCH 1/3] irqchip/gic-v3-its: Zero ITS pages before sharing them with the host Date: Fri, 6 Nov 2026 12:02:19 +0000 Message-ID: <20261106120221.347309-2-fuad.tabba@linux.dev> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261106120221.347309-1-fuad.tabba@linux.dev> References: <20261106120221.347309-1-fuad.tabba@linux.dev> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261106_040234_489410_E1B18606 X-CRM114-Status: GOOD ( 10.55 ) X-Spam-Score: -2.1 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 In a pKVM protected guest, the ITS driver shares every page it allocates for the GIC with the host, through set_memory_decrypted() in its_alloc_pages_node(). its_allocate_prop_table() is the only caller that doesn't pass __GFP_ZERO. It fills the table after the call returns, so until then the host can read the page's previous contents, at least 64KiB of guest memory. Zero every page in its_alloc_pages_node() before it is shared. Every caller except the property table already passes __GFP_ZERO. Fixes: b08e2f42e86b5 ("irqchip/gic-v3-its: Share ITS tables with a non-trusted hypervisor") Cc: stable@vger.kernel.org Signed-off-by: Fuad Tabba --- drivers/irqchip/irq-gic-v3-its.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 282e4bafb084f..de1f1b1f26623 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -218,7 +218,8 @@ static struct page *its_alloc_pages_node(int node, gfp_t gfp, struct page *page; int ret = 0; - page = alloc_pages_node(node, gfp | gfp_flags_quirk, order); + /* Zeroed, as set_memory_decrypted() may share the page with the host */ + page = alloc_pages_node(node, gfp | gfp_flags_quirk | __GFP_ZERO, order); if (!page) return NULL; -- 2.47.3