[3.8.y.z extended stable] Patch "IB/umad: Fix use-after-free on close" has been added to staging queue
Kamal Mostafa
kamal at canonical.com
Mon Jul 21 21:21:42 UTC 2014
This is a note to let you know that I have just added a patch titled
IB/umad: Fix use-after-free on close
to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree
which can be found at:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue
This patch is scheduled to be released in version 3.8.13.27.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
------
>From 0daa99d147c139aa139ae424cddcc74b960d1663 Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche at acm.org>
Date: Fri, 6 Jun 2014 18:25:04 +0200
Subject: IB/umad: Fix use-after-free on close
commit 60e1751cb52cc6d1ae04b6bd3c2b96e770b5823f upstream.
Avoid that closing /dev/infiniband/umad<n> or /dev/infiniband/issm<n>
triggers a use-after-free. __fput() invokes f_op->release() before it
invokes cdev_put(). Make sure that the ib_umad_device structure is
freed by the cdev_put() call instead of f_op->release(). This avoids
that changing the port mode from IB into Ethernet and back to IB
followed by restarting opensmd triggers the following kernel oops:
general protection fault: 0000 [#1] PREEMPT SMP
RIP: 0010:[<ffffffff810cc65c>] [<ffffffff810cc65c>] module_put+0x2c/0x170
Call Trace:
[<ffffffff81190f20>] cdev_put+0x20/0x30
[<ffffffff8118e2ce>] __fput+0x1ae/0x1f0
[<ffffffff8118e35e>] ____fput+0xe/0x10
[<ffffffff810723bc>] task_work_run+0xac/0xe0
[<ffffffff81002a9f>] do_notify_resume+0x9f/0xc0
[<ffffffff814b8398>] int_signal+0x12/0x17
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=75051
Signed-off-by: Bart Van Assche <bvanassche at acm.org>
Reviewed-by: Yann Droneaud <ydroneaud at opteya.com>
Signed-off-by: Roland Dreier <roland at purestorage.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
drivers/infiniband/core/user_mad.c | 30 +++++++++++++++++++-----------
1 file changed, 19 insertions(+), 11 deletions(-)
diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c
index 9bdf576..1acb991 100644
--- a/drivers/infiniband/core/user_mad.c
+++ b/drivers/infiniband/core/user_mad.c
@@ -98,7 +98,7 @@ struct ib_umad_port {
struct ib_umad_device {
int start_port, end_port;
- struct kref ref;
+ struct kobject kobj;
struct ib_umad_port port[0];
};
@@ -134,14 +134,18 @@ static DECLARE_BITMAP(dev_map, IB_UMAD_MAX_PORTS);
static void ib_umad_add_one(struct ib_device *device);
static void ib_umad_remove_one(struct ib_device *device);
-static void ib_umad_release_dev(struct kref *ref)
+static void ib_umad_release_dev(struct kobject *kobj)
{
struct ib_umad_device *dev =
- container_of(ref, struct ib_umad_device, ref);
+ container_of(kobj, struct ib_umad_device, kobj);
kfree(dev);
}
+static struct kobj_type ib_umad_dev_ktype = {
+ .release = ib_umad_release_dev,
+};
+
static int hdr_size(struct ib_umad_file *file)
{
return file->use_pkey_index ? sizeof (struct ib_user_mad_hdr) :
@@ -812,7 +816,7 @@ static int ib_umad_open(struct inode *inode, struct file *filp)
goto out;
}
- kref_get(&port->umad_dev->ref);
+ kobject_get(&port->umad_dev->kobj);
out:
mutex_unlock(&port->file_mutex);
@@ -851,7 +855,7 @@ static int ib_umad_close(struct inode *inode, struct file *filp)
mutex_unlock(&file->port->file_mutex);
kfree(file);
- kref_put(&dev->ref, ib_umad_release_dev);
+ kobject_put(&dev->kobj);
return 0;
}
@@ -902,7 +906,7 @@ static int ib_umad_sm_open(struct inode *inode, struct file *filp)
if (ret)
goto err_clr_sm_cap;
- kref_get(&port->umad_dev->ref);
+ kobject_get(&port->umad_dev->kobj);
return 0;
@@ -932,7 +936,7 @@ static int ib_umad_sm_close(struct inode *inode, struct file *filp)
up(&port->sm_sem);
- kref_put(&port->umad_dev->ref, ib_umad_release_dev);
+ kobject_put(&port->umad_dev->kobj);
return ret;
}
@@ -1000,6 +1004,7 @@ static int find_overflow_devnum(void)
}
static int ib_umad_init_port(struct ib_device *device, int port_num,
+ struct ib_umad_device *umad_dev,
struct ib_umad_port *port)
{
int devnum;
@@ -1032,6 +1037,7 @@ static int ib_umad_init_port(struct ib_device *device, int port_num,
cdev_init(&port->cdev, &umad_fops);
port->cdev.owner = THIS_MODULE;
+ port->cdev.kobj.parent = &umad_dev->kobj;
kobject_set_name(&port->cdev.kobj, "umad%d", port->dev_num);
if (cdev_add(&port->cdev, base, 1))
goto err_cdev;
@@ -1050,6 +1056,7 @@ static int ib_umad_init_port(struct ib_device *device, int port_num,
base += IB_UMAD_MAX_PORTS;
cdev_init(&port->sm_cdev, &umad_sm_fops);
port->sm_cdev.owner = THIS_MODULE;
+ port->sm_cdev.kobj.parent = &umad_dev->kobj;
kobject_set_name(&port->sm_cdev.kobj, "issm%d", port->dev_num);
if (cdev_add(&port->sm_cdev, base, 1))
goto err_sm_cdev;
@@ -1143,7 +1150,7 @@ static void ib_umad_add_one(struct ib_device *device)
if (!umad_dev)
return;
- kref_init(&umad_dev->ref);
+ kobject_init(&umad_dev->kobj, &ib_umad_dev_ktype);
umad_dev->start_port = s;
umad_dev->end_port = e;
@@ -1151,7 +1158,8 @@ static void ib_umad_add_one(struct ib_device *device)
for (i = s; i <= e; ++i) {
umad_dev->port[i - s].umad_dev = umad_dev;
- if (ib_umad_init_port(device, i, &umad_dev->port[i - s]))
+ if (ib_umad_init_port(device, i, umad_dev,
+ &umad_dev->port[i - s]))
goto err;
}
@@ -1163,7 +1171,7 @@ err:
while (--i >= s)
ib_umad_kill_port(&umad_dev->port[i - s]);
- kref_put(&umad_dev->ref, ib_umad_release_dev);
+ kobject_put(&umad_dev->kobj);
}
static void ib_umad_remove_one(struct ib_device *device)
@@ -1177,7 +1185,7 @@ static void ib_umad_remove_one(struct ib_device *device)
for (i = 0; i <= umad_dev->end_port - umad_dev->start_port; ++i)
ib_umad_kill_port(&umad_dev->port[i]);
- kref_put(&umad_dev->ref, ib_umad_release_dev);
+ kobject_put(&umad_dev->kobj);
}
static char *umad_devnode(struct device *dev, umode_t *mode)
--
1.9.1
More information about the kernel-team
mailing list