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 2E61523B613; Mon, 11 Aug 2025 08:48:38 +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=1754902118; cv=none; b=gJMP11DrkUQ7XuUBpm7lm2yW7a2t0yXMqBwEmKfvWU1Ohz8dAtTFy3hnyolN7GVbM+ZGqnoF1hj5PXAi0RORrszeVIEOoj63cCUzR5T+0ivarsxSBthhMBN2qbEXloFzYjF3qn3XzYxnFPKJXGwMDhaE+KhYB+w5buYvS+j9Lp0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754902118; c=relaxed/simple; bh=J/tvAeenWY6r2kQMuQLExQzNUGVbJ5Td0cTgbLYekrA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=MRIlTP6hEy0ymg7m5CFeHDO9SseIIp/aumYWiv7TERg12qWzIj0GzWlMKaF5RY1LoQayibLqbXpGbZw1470CT6toKWKFXL+5OrdTuaP2nKhk2VqVfqjH5SH2oLsUJ9MMlvfDzKeJMfYaFmB5eUP7y3cLO3OYVWWocK1KIBUdMWY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jWN7MfRp; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jWN7MfRp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EB8DDC4CEF1; Mon, 11 Aug 2025 08:48:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754902118; bh=J/tvAeenWY6r2kQMuQLExQzNUGVbJ5Td0cTgbLYekrA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jWN7MfRpqyxbN8Qra7VPZbbaSlsQ5woOMzZZKkCN+c2embl/N2yGINIJ/tjsuHibB o5AFcHHdGCIID4ndaZXMZtE+1kr9TfRnJZ8iA7pefXJ1RiMZhVMhpvYFpicsbuwNoM KuM+qQDyN0NbAfqBmZ5KRtD8+rztH7pWTrZ5tFIPMU3JNlNxAVZI57YlKh2F6p6mS1 QctExT95vObBAiYQYHjH2bwZJyWQDZ/WM7yUFGxTaKxeREO9ckyvaGMO/LBHQvuup9 6nNH/U4yMxynYS+SWF9nMjXZ6CquUI/luxp/WVl/OEGBpilK4aZcBTJpXb7qLysrFQ WX0JG96IP4G9A== Date: Mon, 11 Aug 2025 11:48:29 +0300 From: Mike Rapoport To: Shanker Donthineni Cc: Catalin Marinas , Will Deacon , Marek Szyprowski , Suzuki K Poulose , Steven Price , linux-arm-kernel@lists.infradead.org, Robin Murphy , Gavin Shan , Vikram Sethi , Jason Sequeira , Dev Jain , David Rientjes , linux-kernel@vger.kernel.org, iommu@lists.linux.dev Subject: Re: [RESEND PATCH 1/2] dma/pool: Use vmap() address for memory encryption helpers on ARM64 Message-ID: References: <20250811005036.714274-1-sdonthineni@nvidia.com> <20250811005036.714274-2-sdonthineni@nvidia.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250811005036.714274-2-sdonthineni@nvidia.com> On Sun, Aug 10, 2025 at 07:50:34PM -0500, Shanker Donthineni wrote: > In atomic_pool_expand(), set_memory_encrypted()/set_memory_decrypted() > are currently called with page_to_virt(page). On ARM64 with > CONFIG_DMA_DIRECT_REMAP=y, the atomic pool is mapped via vmap(), so > page_to_virt(page) does not reference the actual mapped region. > > Using this incorrect address can cause encryption attribute updates to > be applied to the wrong memory region. On ARM64 systems with memory > encryption enabled (e.g. CCA), this can lead to data corruption or > crashes. > > Fix this by using the vmap() address ('addr') on ARM64 when invoking > the memory encryption helpers, while retaining the existing > page_to_virt(page) usage for other architectures. > > Fixes: 76a19940bd62 ("dma-direct: atomic allocations must come from atomic coherent pools") > Signed-off-by: Shanker Donthineni > --- > kernel/dma/pool.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c > index 7b04f7575796b..ba08a301590fd 100644 > --- a/kernel/dma/pool.c > +++ b/kernel/dma/pool.c > @@ -81,6 +81,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, > { > unsigned int order; > struct page *page = NULL; > + void *vaddr; > void *addr; > int ret = -ENOMEM; > > @@ -113,8 +114,8 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, > * Memory in the atomic DMA pools must be unencrypted, the pools do not > * shrink so no re-encryption occurs in dma_direct_free(). > */ > - ret = set_memory_decrypted((unsigned long)page_to_virt(page), > - 1 << order); > + vaddr = IS_ENABLED(CONFIG_ARM64) ? addr : page_to_virt(page); There's address calculation just before this code: #ifdef CONFIG_DMA_DIRECT_REMAP addr = dma_common_contiguous_remap(page, pool_size, pgprot_dmacoherent(PAGE_KERNEL), __builtin_return_address(0)); if (!addr) goto free_page; #else addr = page_to_virt(page); #endif It should be enough to s/page_to_virt(page)/addr in the call to set_memory_decrypted(). > + ret = set_memory_decrypted((unsigned long)vaddr, 1 << order); > if (ret) > goto remove_mapping; > ret = gen_pool_add_virt(pool, (unsigned long)addr, page_to_phys(page), > @@ -126,8 +127,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, > return 0; > > encrypt_mapping: > - ret = set_memory_encrypted((unsigned long)page_to_virt(page), > - 1 << order); > + ret = set_memory_encrypted((unsigned long)vaddr, 1 << order); > if (WARN_ON_ONCE(ret)) { > /* Decrypt succeeded but encrypt failed, purposely leak */ > goto out; > -- > 2.25.1 > -- Sincerely yours, Mike.