[PATCH] ipmi: ipmi_devintf: compat_ioctl method failes to take ipmi_mutex

From: Benjamin LaHaise
Date: Mon May 13 2013 - 15:39:39 EST


When a 32 bit version of ipmitool is used on a 64 bit kernel, the
ipmi_devintf code fails to correctly acquire ipmi_mutex. This results in
incomplete data being retrieved in some cases, or other possible failures.
Add a wrapper around compat_ipmi_ioctl() to take ipmi_mutex to fix this.
This is probably a candidate for -stable as well.

Signed-off-by: Benjamin LaHaise <bcrl@xxxxxxxxx>
---
drivers/char/ipmi/ipmi_devintf.c | 14 +++++++++++++-
1 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_devintf.c b/drivers/char/ipmi/ipmi_devintf.c
index 9eb360f..d5a5f02 100644
--- a/drivers/char/ipmi/ipmi_devintf.c
+++ b/drivers/char/ipmi/ipmi_devintf.c
@@ -837,13 +837,25 @@ static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
return ipmi_ioctl(filep, cmd, arg);
}
}
+
+static long unlocked_compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret;
+
+ mutex_lock(&ipmi_mutex);
+ ret = compat_ipmi_ioctl(filep, cmd, arg);
+ mutex_unlock(&ipmi_mutex);
+
+ return ret;
+}
#endif

static const struct file_operations ipmi_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = ipmi_unlocked_ioctl,
#ifdef CONFIG_COMPAT
- .compat_ioctl = compat_ipmi_ioctl,
+ .compat_ioctl = unlocked_compat_ipmi_ioctl,
#endif
.open = ipmi_open,
.release = ipmi_release,
--
1.7.4.1


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