linux-kernel - [PATCH AUTOSEL 5.2 27/44] dma-direct: don't truncate dma_required

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 20 Aug 2019 09:40:11 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Lucas Stach <l.stach@...gutronix.de>,
        Atish Patra <atish.patra@....com>,
        Christoph Hellwig <hch@....de>,
        Sasha Levin <sashal@...nel.org>,
        iommu@...ts.linux-foundation.org
Subject: [PATCH AUTOSEL 5.2 27/44] dma-direct: don't truncate dma_required_mask to bus addressing capabilities

From: Lucas Stach <l.stach@...gutronix.de>

[ Upstream commit d8ad55538abe443919e20e0bb996561bca9cad84 ]

The dma required_mask needs to reflect the actual addressing capabilities
needed to handle the whole system RAM. When truncated down to the bus
addressing capabilities dma_addressing_limited() will incorrectly signal
no limitations for devices which are restricted by the bus_dma_mask.

Fixes: b4ebe6063204 (dma-direct: implement complete bus_dma_mask handling)
Signed-off-by: Lucas Stach <l.stach@...gutronix.de>
Tested-by: Atish Patra <atish.patra@....com>
Signed-off-by: Christoph Hellwig <hch@....de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 kernel/dma/direct.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 2c2772e9702ab..9912be7a970de 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -55,9 +55,6 @@ u64 dma_direct_get_required_mask(struct device *dev)
 {
 	u64 max_dma = phys_to_dma_direct(dev, (max_pfn - 1) << PAGE_SHIFT);
 
-	if (dev->bus_dma_mask && dev->bus_dma_mask < max_dma)
-		max_dma = dev->bus_dma_mask;
-
 	return (1ULL << (fls64(max_dma) - 1)) * 2 - 1;
 }
 
-- 
2.20.1