Previously, capability was checked using capable(), which verified that the
caller of the ioctl system call had the required capability. In addition,
the result of the check would be stored in the HCI_SOCK_TRUSTED flag,
making it persistent for the socket.
However, malicious programs can abuse this approach by deliberately sharing
an HCI socket with a privileged task. The HCI socket will be marked as
trusted when the privileged task occasionally makes an ioctl call.
This problem can be solved by using sk_capable() to check capability, which
ensures that not only the current task but also the socket opener has the
specified capability, thus reducing the risk of privilege escalation
through the previously identified vulnerability.
Cc: stable(a)vger.kernel.org
Fixes: f81f5b2db869 ("Bluetooth: Send control open and close messages for HCI raw sockets")
Signed-off-by: Ruihan Li <lrh2000(a)pku.edu.cn>
---
net/bluetooth/hci_sock.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 065812232..f597fe0db 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -1003,7 +1003,14 @@ static int hci_sock_ioctl(struct socket *sock, unsigned int cmd,
if (hci_sock_gen_cookie(sk)) {
struct sk_buff *skb;
- if (capable(CAP_NET_ADMIN))
+ /* Perform careful checks before setting the HCI_SOCK_TRUSTED
+ * flag. Make sure that not only the current task but also
+ * the socket opener has the required capability, since
+ * privileged programs can be tricked into making ioctl calls
+ * on HCI sockets, and the socket should not be marked as
+ * trusted simply because the ioctl caller is privileged.
+ */
+ if (sk_capable(sk, CAP_NET_ADMIN))
hci_sock_set_flag(sk, HCI_SOCK_TRUSTED);
/* Send event to monitor */
--
2.40.0
commit ba9182a89626d5f83c2ee4594f55cb9c1e60f0e2 upstream.
After a successful cpuset_can_attach() call which increments the
attach_in_progress flag, either cpuset_cancel_attach() or cpuset_attach()
will be called later. In cpuset_attach(), tasks in cpuset_attach_wq,
if present, will be woken up at the end. That is not the case in
cpuset_cancel_attach(). So missed wakeup is possible if the attach
operation is somehow cancelled. Fix that by doing the wakeup in
cpuset_cancel_attach() as well.
Fixes: e44193d39e8d ("cpuset: let hotplug propagation work wait for task attaching")
Signed-off-by: Waiman Long <longman(a)redhat.com>
Reviewed-by: Michal Koutný <mkoutny(a)suse.com>
Cc: stable(a)vger.kernel.org # v3.11+
Signed-off-by: Tejun Heo <tj(a)kernel.org>
---
kernel/cgroup/cpuset.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 0b82e3857d33..20c1ccc6a0bb 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1508,7 +1508,9 @@ static void cpuset_cancel_attach(struct cgroup_taskset *tset)
cs = css_cs(css);
mutex_lock(&cpuset_mutex);
- css_cs(css)->attach_in_progress--;
+ cs->attach_in_progress--;
+ if (!cs->attach_in_progress)
+ wake_up(&cpuset_attach_wq);
mutex_unlock(&cpuset_mutex);
}
--
2.31.1
commit ba9182a89626d5f83c2ee4594f55cb9c1e60f0e2 upstream.
After a successful cpuset_can_attach() call which increments the
attach_in_progress flag, either cpuset_cancel_attach() or cpuset_attach()
will be called later. In cpuset_attach(), tasks in cpuset_attach_wq,
if present, will be woken up at the end. That is not the case in
cpuset_cancel_attach(). So missed wakeup is possible if the attach
operation is somehow cancelled. Fix that by doing the wakeup in
cpuset_cancel_attach() as well.
Fixes: e44193d39e8d ("cpuset: let hotplug propagation work wait for task attaching")
Signed-off-by: Waiman Long <longman(a)redhat.com>
Reviewed-by: Michal Koutný <mkoutny(a)suse.com>
Cc: stable(a)vger.kernel.org # v3.11+
Signed-off-by: Tejun Heo <tj(a)kernel.org>
---
kernel/cgroup/cpuset.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index c6d412cebc43..3067d3e5a51d 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1504,7 +1504,9 @@ static void cpuset_cancel_attach(struct cgroup_taskset *tset)
cs = css_cs(css);
mutex_lock(&cpuset_mutex);
- css_cs(css)->attach_in_progress--;
+ cs->attach_in_progress--;
+ if (!cs->attach_in_progress)
+ wake_up(&cpuset_attach_wq);
mutex_unlock(&cpuset_mutex);
}
--
2.31.1
Hi,
please pick
1e020e1b96afd ("ubi: Fix failure attaching when vid_hdr offset equals to (sub)page size")
from linux-next to stable trees.
The commit fixes a problem with another recent commit
1b42b1a36fc94 ("ubi: ensure that VID header offset ... size")
which has already made it to stable trees and thereby broke attaching
UBI and hence renders devices unbootable.
As a temporary fix I have applied this patch downstream in OpenWrt.
Thank you!
Best regards
Daniel
----- Forwarded message from Daniel Golle <daniel(a)makrotopia.org> -----
Date: Sat, 15 Apr 2023 00:12:46 +0100
From: Daniel Golle <daniel(a)makrotopia.org>
To: Richard Weinberger <richard(a)nod.at>
Cc: Miquel Raynal <miquel.raynal(a)bootlin.com>, chengzhihao1 <chengzhihao1(a)huawei.com>, Nicolas Schichan <nschichan(a)freebox.fr>, George Kennedy <george.kennedy(a)oracle.com>, linux-kernel <linux-kernel(a)vger.kernel.org>, linux-mtd
<linux-mtd(a)lists.infradead.org>, Sascha Hauer <s.hauer(a)pengutronix.de>, yi zhang <yi.zhang(a)huawei.com>
Subject: Re: [PATCH -next v3] ubi: Fix failure attaching when vid_hdr offset equals to (sub)page size
Hi Richard,
On Wed, Mar 29, 2023 at 11:33:40PM +0200, Richard Weinberger wrote:
> ----- Ursprüngliche Mail -----
> > Von: "Miquel Raynal" <miquel.raynal(a)bootlin.com>
> >> Thanks for testing.
> >>
> >> > Tested-by: Nicolas Schichan <nschichan(a)freebox.fr>
> >
> > Same here.
> >
> > Tested-by: Miquel Raynal <miquel.raynal(a)bootlin.com> # v5.10, v4.19
>
> Applied to next, PR will follow soon.
As stable linux trees are affected I wonder when this will hit
linux-stable, ie. will it be part of 5.15.108, for example?
Cheers
Daniel
----- End forwarded message -----
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x eee87853794187f6adbe19533ed79c8b44b36a91
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041705-gauze-elated-d7c7@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
eee878537941 ("cgroup/cpuset: Add cpuset_can_fork() and cpuset_cancel_fork() methods")
42a11bf5c543 ("cgroup/cpuset: Make cpuset_fork() handle CLONE_INTO_CGROUP properly")
18f9a4d47527 ("cgroup/cpuset: Skip spread flags update on v2")
e2d59900d936 ("cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective")
18065ebe9b33 ("cgroup/cpuset: Miscellaneous cleanups & add helper functions")
f9da322e864e ("cgroup: cleanup comments")
8ca1b5a49885 ("mm/page_alloc: detect allocation forbidden by cpuset and bail out early")
b94f9ac79a73 ("cgroup/cpuset: Change references of cpuset_mutex to cpuset_rwsem")
69dc8010b8fc ("Merge branch 'for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From eee87853794187f6adbe19533ed79c8b44b36a91 Mon Sep 17 00:00:00 2001
From: Waiman Long <longman(a)redhat.com>
Date: Tue, 11 Apr 2023 09:35:59 -0400
Subject: [PATCH] cgroup/cpuset: Add cpuset_can_fork() and cpuset_cancel_fork()
methods
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
In the case of CLONE_INTO_CGROUP, not all cpusets are ready to accept
new tasks. It is too late to check that in cpuset_fork(). So we need
to add the cpuset_can_fork() and cpuset_cancel_fork() methods to
pre-check it before we can allow attachment to a different cpuset.
We also need to set the attach_in_progress flag to alert other code
that a new task is going to be added to the cpuset.
Fixes: ef2c41cf38a7 ("clone3: allow spawning processes into cgroups")
Suggested-by: Michal Koutný <mkoutny(a)suse.com>
Signed-off-by: Waiman Long <longman(a)redhat.com>
Cc: stable(a)vger.kernel.org # v5.7+
Signed-off-by: Tejun Heo <tj(a)kernel.org>
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 2ccfae74acf9..166a45019f66 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -2453,6 +2453,20 @@ static int fmeter_getrate(struct fmeter *fmp)
static struct cpuset *cpuset_attach_old_cs;
+/*
+ * Check to see if a cpuset can accept a new task
+ * For v1, cpus_allowed and mems_allowed can't be empty.
+ * For v2, effective_cpus can't be empty.
+ * Note that in v1, effective_cpus = cpus_allowed.
+ */
+static int cpuset_can_attach_check(struct cpuset *cs)
+{
+ if (cpumask_empty(cs->effective_cpus) ||
+ (!is_in_v2_mode() && nodes_empty(cs->mems_allowed)))
+ return -ENOSPC;
+ return 0;
+}
+
/* Called by cgroups to determine if a cpuset is usable; cpuset_rwsem held */
static int cpuset_can_attach(struct cgroup_taskset *tset)
{
@@ -2467,16 +2481,9 @@ static int cpuset_can_attach(struct cgroup_taskset *tset)
percpu_down_write(&cpuset_rwsem);
- /* allow moving tasks into an empty cpuset if on default hierarchy */
- ret = -ENOSPC;
- if (!is_in_v2_mode() &&
- (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
- goto out_unlock;
-
- /*
- * Task cannot be moved to a cpuset with empty effective cpus.
- */
- if (cpumask_empty(cs->effective_cpus))
+ /* Check to see if task is allowed in the cpuset */
+ ret = cpuset_can_attach_check(cs);
+ if (ret)
goto out_unlock;
cgroup_taskset_for_each(task, css, tset) {
@@ -2493,7 +2500,6 @@ static int cpuset_can_attach(struct cgroup_taskset *tset)
* changes which zero cpus/mems_allowed.
*/
cs->attach_in_progress++;
- ret = 0;
out_unlock:
percpu_up_write(&cpuset_rwsem);
return ret;
@@ -3264,6 +3270,68 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css)
percpu_up_write(&cpuset_rwsem);
}
+/*
+ * In case the child is cloned into a cpuset different from its parent,
+ * additional checks are done to see if the move is allowed.
+ */
+static int cpuset_can_fork(struct task_struct *task, struct css_set *cset)
+{
+ struct cpuset *cs = css_cs(cset->subsys[cpuset_cgrp_id]);
+ bool same_cs;
+ int ret;
+
+ rcu_read_lock();
+ same_cs = (cs == task_cs(current));
+ rcu_read_unlock();
+
+ if (same_cs)
+ return 0;
+
+ lockdep_assert_held(&cgroup_mutex);
+ percpu_down_write(&cpuset_rwsem);
+
+ /* Check to see if task is allowed in the cpuset */
+ ret = cpuset_can_attach_check(cs);
+ if (ret)
+ goto out_unlock;
+
+ ret = task_can_attach(task, cs->effective_cpus);
+ if (ret)
+ goto out_unlock;
+
+ ret = security_task_setscheduler(task);
+ if (ret)
+ goto out_unlock;
+
+ /*
+ * Mark attach is in progress. This makes validate_change() fail
+ * changes which zero cpus/mems_allowed.
+ */
+ cs->attach_in_progress++;
+out_unlock:
+ percpu_up_write(&cpuset_rwsem);
+ return ret;
+}
+
+static void cpuset_cancel_fork(struct task_struct *task, struct css_set *cset)
+{
+ struct cpuset *cs = css_cs(cset->subsys[cpuset_cgrp_id]);
+ bool same_cs;
+
+ rcu_read_lock();
+ same_cs = (cs == task_cs(current));
+ rcu_read_unlock();
+
+ if (same_cs)
+ return;
+
+ percpu_down_write(&cpuset_rwsem);
+ cs->attach_in_progress--;
+ if (!cs->attach_in_progress)
+ wake_up(&cpuset_attach_wq);
+ percpu_up_write(&cpuset_rwsem);
+}
+
/*
* Make sure the new task conform to the current state of its parent,
* which could have been changed by cpuset just after it inherits the
@@ -3292,6 +3360,11 @@ static void cpuset_fork(struct task_struct *task)
percpu_down_write(&cpuset_rwsem);
guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
cpuset_attach_task(cs, task);
+
+ cs->attach_in_progress--;
+ if (!cs->attach_in_progress)
+ wake_up(&cpuset_attach_wq);
+
percpu_up_write(&cpuset_rwsem);
}
@@ -3305,6 +3378,8 @@ struct cgroup_subsys cpuset_cgrp_subsys = {
.attach = cpuset_attach,
.post_attach = cpuset_post_attach,
.bind = cpuset_bind,
+ .can_fork = cpuset_can_fork,
+ .cancel_fork = cpuset_cancel_fork,
.fork = cpuset_fork,
.legacy_cftypes = legacy_files,
.dfl_cftypes = dfl_files,