linux-kernel - [PATCH V2] scsi: lpfc: Switch memcpy_fromio() to __read32

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>] [day] [month] [year] [list]

Message-Id: <1545208274-13736-1-git-send-email-chenhc@lemote.com>
Date:   Wed, 19 Dec 2018 16:31:14 +0800
From:   Huacai Chen <chenhc@...ote.com>
To:     "James E . J . Bottomley" <jejb@...ux.vnet.ibm.com>
Cc:     "Martin K . Petersen" <martin.petersen@...cle.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Fuxin Zhang <zhangfx@...ote.com>, linux-scsi@...r.kernel.org,
        linux-kernel@...r.kernel.org, Huacai Chen <chenhc@...ote.com>,
        stable@...r.kernel.org
Subject: [PATCH V2] scsi: lpfc: Switch memcpy_fromio() to __read32_copy()

In commit bc73905abf770192 ("[SCSI] lpfc 8.3.16: SLI Additions, updates,
and code cleanup"), lpfc_memcpy_to_slim() have switched memcpy_toio() to
__write32_copy() in order to prevent unaligned 64 bit copy. Recently, we
found that lpfc_memcpy_from_slim() have similar issues, so let it switch
memcpy_fromio() to __read32_copy().

As maintainer says, it seems that we can hardly see a real "unaligned 64
bit copy", but this patch is still useful. Because in our tests we found
that lpfc doesn't support 128 bit access, but some optimized memcpy()
use 128 bit access (at lease on Loongson).

Cc: stable@...r.kernel.org
Signed-off-by: Huacai Chen <chenhc@...ote.com>
---
V2: Update commit message.

 drivers/scsi/lpfc/lpfc_compat.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_compat.h b/drivers/scsi/lpfc/lpfc_compat.h
index 43cf46a..0cd1e3c 100644
--- a/drivers/scsi/lpfc/lpfc_compat.h
+++ b/drivers/scsi/lpfc/lpfc_compat.h
@@ -91,8 +91,8 @@ lpfc_memcpy_to_slim( void __iomem *dest, void *src, unsigned int bytes)
 static inline void
 lpfc_memcpy_from_slim( void *dest, void __iomem *src, unsigned int bytes)
 {
-	/* actually returns 1 byte past dest */
-	memcpy_fromio( dest, src, bytes);
+	/* convert bytes in argument list to word count for copy function */
+	__ioread32_copy(dest, src, bytes / sizeof(uint32_t));
 }
 
 #endif	/* __BIG_ENDIAN */
-- 
2.7.0