From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.240 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793966555; b=xcwovJSxuV8EIv22Yvh6yoge/CdVzBlC3C4mgmQO8QYlH7Yyb1RdCw3tCzx+WZzaGVaE 3olv1dLfYxbndBTCml7V2yDcD/09BuJYWyqG62nTsedwBwiQrCzWFDHseZ9HujRouXF1f I8rl7YShZijg+tEaeXuhyfK22BEP4Exv5YFfwHUm6V0Bft/P4EA+6pNQnwdFX/upZ3v63 2uFcePXqPCrGw/1XxS1Z+qpP/B7JzN8xBPqUpCE3ROP+OjD3rAqLhQwz+N36wPr2digQ7 H2HS36xnO46XRdGnhaGfUy4nYrypcbD9JnAPYLi5DXH1Ebm6isp13GazhxIvu718tqg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793966555; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=b32C5Yk9u4T7M0pDjYb1nHa0EfPn+C/TBJuye6XXKRU=; b=0Sao6UDZOjth11U6mvqi1oj0Nz6z5ZVMV4ijercgPyrdc4A28rIqXSZ9rTHLR6lIXI4d EJe3A8C4xvWWLZw1/r8/MUpdMPTx8Kk10tsjHaAv+tPUietSSQYhfOb5edhJkioH2R9RJ x0/0XiYY3gQRb1Q97VyxJkXGE+Ejzk9hKrER5d2QcIL7DXkhy8SzmmMcrw3vG0Vd8WH8d 3rAjcDPP2AQ4vVVGAMRn3IScpOhIPvSIF8IYHicVOjFo6A/SZZexw242yVxpRphYwE9X+ z/f70cweC+4SytzID/lVbMqxF8yHQ4jeWvQCN5dl2q5G3U5PmF9qgqv6bczcUNxjTQw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=XIW4+VP5; arc=none smtp.remote-ip=95.215.58.240 Received: from mta1.migadu.com (out-240.mta1.migadu.com [95.215.58.240]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 270CA606D81C for ; Fri, 6 Nov 2026 12:02:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 270CA606D81C Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; 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 X-Envelope-To: linux-kernel@vger.kernel.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-kernel@vger.kernel.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-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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