linux-kernel - [PATCH v3] isp1760: Flush the D-cache for the pipe-in transfer buffers

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]

Date:	Tue, 02 Feb 2010 15:31:02 +0000
From:	Catalin Marinas <catalin.marinas@....com>
To:	linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:	Greg KH <greg@...ah.com>,
	Matthew Dharm <mdharm-kernel@...-eyed-alien.net>,
	Oliver Neukum <oliver@...kum.org>,
	Sebastian Siewior <bigeasy@...utronix.de>
Subject: [PATCH v3] isp1760: Flush the D-cache for the pipe-in transfer buffers

When the HDC driver writes the data to the transfer buffers it pollutes
the D-cache (unlike DMA drivers where the device writes the data). If
the corresponding pages get mapped into user space, there are no
additional cache flushing operations performed and this causes random
user space faults on architectures with separate I and D caches
(Harvard) or those with aliasing D-cache.

Signed-off-by: Catalin Marinas <catalin.marinas@....com>
Cc: Matthew Dharm <mdharm-kernel@...-eyed-alien.net>
Cc: Greg KH <greg@...ah.com>
Cc: Sebastian Siewior <bigeasy@...utronix.de>
Cc: Oliver Neukum <oliver@...kum.org>
---

The changes in the third version of this patch include flushing the
transfer buffer for all in-pipes except the PIPE_CONTROL ones.


 drivers/usb/host/isp1760-hcd.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/host/isp1760-hcd.c b/drivers/usb/host/isp1760-hcd.c
index 27b8f7c..9f01293 100644
--- a/drivers/usb/host/isp1760-hcd.c
+++ b/drivers/usb/host/isp1760-hcd.c
@@ -17,7 +17,9 @@
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/io.h>
+#include <linux/mm.h>
 #include <asm/unaligned.h>
+#include <asm/cacheflush.h>
 
 #include "../core/hcd.h"
 #include "isp1760-hcd.h"
@@ -904,6 +906,14 @@ __acquires(priv->lock)
 			status = 0;
 	}
 
+	if (usb_pipein(urb->pipe) && usb_pipetype(urb->pipe) != PIPE_CONTROL) {
+		void *ptr;
+		for (ptr = urb->transfer_buffer;
+		     ptr < urb->transfer_buffer + urb->transfer_buffer_length;
+		     ptr += PAGE_SIZE)
+			flush_dcache_page(virt_to_page(ptr));
+	}
+
 	/* complete() can reenter this HCD */
 	usb_hcd_unlink_urb_from_ep(priv_to_hcd(priv), urb);
 	spin_unlock(&priv->lock);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/