From 490462c2686df6e35c21d1efe935e0b4a3bddb39 Mon Sep 17 00:00:00 2001
From: Bryan O'Sullivan <bos@pathscale.com>
Date: Thu, 15 Mar 2007 14:45:10 -0700
Subject: [PATCH] IB/ipath: Prevent random program use of diags interface
To prevent random utility reads and writes of the diag interface to the
chip, we first require a handshake of reading from offset 0 and writing
to offset 0 before any other reads or writes can be done through the
diags device. Otherwise chip errors can be triggered.
Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
---
drivers/infiniband/hw/ipath/ipath_diag.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/hw/ipath/ipath_diag.c b/drivers/infiniband/hw/ipath/ipath_diag.c
index 0f13a2182c..63e8368b0e 100644
--- a/drivers/infiniband/hw/ipath/ipath_diag.c
+++ b/drivers/infiniband/hw/ipath/ipath_diag.c
@@ -296,7 +296,7 @@ static int ipath_diag_open(struct inode *in, struct file *fp)
}
fp->private_data = dd;
- ipath_diag_inuse = 1;
+ ipath_diag_inuse = -2;
diag_set_link = 0;
ret = 0;
@@ -461,6 +461,8 @@ static ssize_t ipath_diag_read(struct file *fp, char __user *data,
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
+ else if (ipath_diag_inuse < 1 && (*off || count != 8))
+ ret = -EINVAL; /* prevent cat /dev/ipath_diag* */
else if ((count % 8) || (*off % 8))
/* address or length not 64-bit aligned; do 32-bit reads */
ret = ipath_read_umem32(dd, data, kreg_base + *off, count);
@@ -470,6 +472,8 @@ static ssize_t ipath_diag_read(struct file *fp, char __user *data,
if (ret >= 0) {
*off += count;
ret = count;
+ if (ipath_diag_inuse == -2)
+ ipath_diag_inuse++;
}
return ret;
@@ -489,6 +493,9 @@ static ssize_t ipath_diag_write(struct file *fp, const char __user *data,
else if ((count % 4) || (*off % 4))
/* address or length is not 32-bit aligned, hence invalid */
ret = -EINVAL;
+ else if ((ipath_diag_inuse == -1 && (*off || count != 8)) ||
+ ipath_diag_inuse == -2) /* read qw off 0, write qw off 0 */
+ ret = -EINVAL; /* before any other write allowed */
else if ((count % 8) || (*off % 8))
/* address or length not 64-bit aligned; do 32-bit writes */
ret = ipath_write_umem32(dd, kreg_base + *off, data, count);
@@ -498,6 +505,8 @@ static ssize_t ipath_diag_write(struct file *fp, const char __user *data,
if (ret >= 0) {
*off += count;
ret = count;
+ if (ipath_diag_inuse == -1)
+ ipath_diag_inuse = 1; /* all read/write OK now */
}
return ret;
--
2.25.4