linux-kernel - [PATCH] iommu: fix integer truncation

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-next>] [day] [month] [year] [list]

Message-Id: <20190617133101.2817807-1-arnd@arndb.de>
Date:   Mon, 17 Jun 2019 15:30:54 +0200
From:   Arnd Bergmann <arnd@...db.de>
To:     Joerg Roedel <joro@...tes.org>
Cc:     Christoph Hellwig <hch@....de>, Arnd Bergmann <arnd@...db.de>,
        Srinath Mannam <srinath.mannam@...adcom.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Oza Pawandeep <poza@...eaurora.org>,
        Robin Murphy <robin.murphy@....com>,
        Eric Auger <eric.auger@...hat.com>,
        Julien Grall <julien.grall@....com>,
        Marc Zyngier <marc.zyngier@....com>,
        iommu@...ts.linux-foundation.org, linux-kernel@...r.kernel.org
Subject: [PATCH] iommu: fix integer truncation

On 32-bit architectures, phys_addr_t may be different from dma_add_t,
both smaller and bigger. This can lead to an overflow during an assignment
that clang warns about:

drivers/iommu/dma-iommu.c:230:10: error: implicit conversion from 'dma_addr_t' (aka 'unsigned long long') to
      'phys_addr_t' (aka 'unsigned int') changes value from 18446744073709551615 to 4294967295 [-Werror,-Wconstant-conversion]

Use phys_addr_t here because that is the type that the variable was
declared as.

Fixes: aadad097cd46 ("iommu/dma: Reserve IOVA for PCIe inaccessible DMA address")
Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
 drivers/iommu/dma-iommu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index cc0613c83d71..a9f13313a22f 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -226,8 +226,8 @@ static int iova_reserve_pci_windows(struct pci_dev *dev,
 		start = window->res->end - window->offset + 1;
 		/* If window is last entry */
 		if (window->node.next == &bridge->dma_ranges &&
-		    end != ~(dma_addr_t)0) {
-			end = ~(dma_addr_t)0;
+		    end != ~(phys_addr_t)0) {
+			end = ~(phys_addr_t)0;
 			goto resv_iova;
 		}
 	}
-- 
2.20.0