From: Zhongqiu Han <quic_zhonhan(a)quicinc.com>
stable inclusion
from stable-v6.6.31
commit 95ca7c90eaf5ea8a8460536535101e3e81160e2a
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9UG5Z
CVE: CVE-2024-36899
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id…
--------------------------------
[ Upstream commit 02f6b0e1ec7e0e7d059dddc893645816552039da ]
The use-after-free issue occurs as follows: when the GPIO chip device file
is being closed by invoking gpio_chrdev_release(), watched_lines is freed
by bitmap_free(), but the unregistration of lineinfo_changed_nb notifier
chain failed due to waiting write rwsem. Additionally, one of the GPIO
chip's lines is also in the release process and holds the notifier chain's
read rwsem. Consequently, a race condition leads to the use-after-free of
watched_lines.
Here is the typical stack when issue happened:
[free]
gpio_chrdev_release()
--> bitmap_free(cdev->watched_lines) <-- freed
--> blocking_notifier_chain_unregister()
--> down_write(&nh->rwsem) <-- waiting rwsem
--> __down_write_common()
--> rwsem_down_write_slowpath()
--> schedule_preempt_disabled()
--> schedule()
[use]
st54spi_gpio_dev_release()
--> gpio_free()
--> gpiod_free()
--> gpiod_free_commit()
--> gpiod_line_state_notify()
--> blocking_notifier_call_chain()
--> down_read(&nh->rwsem); <-- held rwsem
--> notifier_call_chain()
--> lineinfo_changed_notify()
--> test_bit(xxxx, cdev->watched_lines) <-- use after free
The side effect of the use-after-free issue is that a GPIO line event is
being generated for userspace where it shouldn't. However, since the chrdev
is being closed, userspace won't have the chance to read that event anyway.
To fix the issue, call the bitmap_free() function after the unregistration
of lineinfo_changed_nb notifier chain.
Fixes: 51c1064e82e7 ("gpiolib: add new ioctl() for monitoring changes in line info")
Signed-off-by: Zhongqiu Han <quic_zhonhan(a)quicinc.com>
Link: https://lore.kernel.org/r/20240505141156.2944912-1-quic_zhonhan@quicinc.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski(a)linaro.org>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
Signed-off-by: Ma Wupeng <mawupeng1(a)huawei.com>
---
drivers/gpio/gpiolib-cdev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index 84125e55de10..ebf5b8ef3b5d 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -2816,11 +2816,11 @@ static int gpio_chrdev_release(struct inode *inode, struct file *file)
struct gpio_chardev_data *cdev = file->private_data;
struct gpio_device *gdev = cdev->gdev;
- bitmap_free(cdev->watched_lines);
blocking_notifier_chain_unregister(&gdev->device_notifier,
&cdev->device_unregistered_nb);
blocking_notifier_chain_unregister(&gdev->line_state_notifier,
&cdev->lineinfo_changed_nb);
+ bitmap_free(cdev->watched_lines);
gpio_device_put(gdev);
kfree(cdev);
--
2.25.1
From: Thadeu Lima de Souza Cascardo <cascardo(a)igalia.com>
stable inclusion
from stable-v4.19.314
commit 3cdc34d76c4f777579e28ad373979d36c030cfd3
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9TMCC
CVE: CVE-2024-36883
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id…
--------------------------------
commit a26ff37e624d12e28077e5b24d2b264f62764ad6 upstream.
net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.
It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.
Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo(a)igalia.com>
Fixes: 073862ba5d24 ("netns: fix net_alloc_generic()")
Reviewed-by: Eric Dumazet <edumazet(a)google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu(a)amazon.com>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20240502132006.3430840-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni <pabeni(a)redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com>
---
net/core/net_namespace.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 975cf8cebc34..94dc7e99e200 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -63,12 +63,15 @@ static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS;
static struct net_generic *net_alloc_generic(void)
{
+ unsigned int gen_ptrs = READ_ONCE(max_gen_ptrs);
+ unsigned int generic_size;
struct net_generic *ng;
- unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
+
+ generic_size = offsetof(struct net_generic, ptr[gen_ptrs]);
ng = kzalloc(generic_size, GFP_KERNEL);
if (ng)
- ng->s.len = max_gen_ptrs;
+ ng->s.len = gen_ptrs;
return ng;
}
@@ -1018,7 +1021,11 @@ static int register_pernet_operations(struct list_head *list,
if (error < 0)
return error;
*ops->id = error;
- max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1);
+ /* This does not require READ_ONCE as writers already hold
+ * pernet_ops_rwsem. But WRITE_ONCE is needed to protect
+ * net_alloc_generic.
+ */
+ WRITE_ONCE(max_gen_ptrs, max(max_gen_ptrs, *ops->id + 1));
}
error = __register_pernet_operations(list, ops);
if (error) {
--
2.34.1
From: Thadeu Lima de Souza Cascardo <cascardo(a)igalia.com>
stable inclusion
from stable-v5.10.217
commit 0c3248bc708a7797be573214065cf908ff1f54c7
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9TMCC
CVE: CVE-2024-36883
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id…
--------------------------------
commit a26ff37e624d12e28077e5b24d2b264f62764ad6 upstream.
net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.
It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.
Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo(a)igalia.com>
Fixes: 073862ba5d24 ("netns: fix net_alloc_generic()")
Reviewed-by: Eric Dumazet <edumazet(a)google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu(a)amazon.com>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20240502132006.3430840-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni <pabeni(a)redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com>
---
net/core/net_namespace.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index cbff7d94b993..15995cbe6b74 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -86,12 +86,15 @@ u64 __net_gen_cookie(struct net *net)
static struct net_generic *net_alloc_generic(void)
{
+ unsigned int gen_ptrs = READ_ONCE(max_gen_ptrs);
+ unsigned int generic_size;
struct net_generic *ng;
- unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
+
+ generic_size = offsetof(struct net_generic, ptr[gen_ptrs]);
ng = kzalloc(generic_size, GFP_KERNEL);
if (ng)
- ng->s.len = max_gen_ptrs;
+ ng->s.len = gen_ptrs;
return ng;
}
@@ -1234,7 +1237,11 @@ static int register_pernet_operations(struct list_head *list,
if (error < 0)
return error;
*ops->id = error;
- max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1);
+ /* This does not require READ_ONCE as writers already hold
+ * pernet_ops_rwsem. But WRITE_ONCE is needed to protect
+ * net_alloc_generic.
+ */
+ WRITE_ONCE(max_gen_ptrs, max(max_gen_ptrs, *ops->id + 1));
}
error = __register_pernet_operations(list, ops);
if (error) {
--
2.34.1
From: Thadeu Lima de Souza Cascardo <cascardo(a)igalia.com>
stable inclusion
from stable-v5.10.217
commit 0c3248bc708a7797be573214065cf908ff1f54c7
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9TMCC
CVE: CVE-2024-36883
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id…
--------------------------------
commit a26ff37e624d12e28077e5b24d2b264f62764ad6 upstream.
net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.
It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.
Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo(a)igalia.com>
Fixes: 073862ba5d24 ("netns: fix net_alloc_generic()")
Reviewed-by: Eric Dumazet <edumazet(a)google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu(a)amazon.com>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20240502132006.3430840-1-cascardo@igalia.com
Signed-off-by: Paolo Abeni <pabeni(a)redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com>
---
net/core/net_namespace.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 20a0fc4d059b..cd867cb408c9 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -74,12 +74,15 @@ DEFINE_COOKIE(net_cookie);
static struct net_generic *net_alloc_generic(void)
{
+ unsigned int gen_ptrs = READ_ONCE(max_gen_ptrs);
+ unsigned int generic_size;
struct net_generic *ng;
- unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
+
+ generic_size = offsetof(struct net_generic, ptr[gen_ptrs]);
ng = kzalloc(generic_size, GFP_KERNEL);
if (ng)
- ng->s.len = max_gen_ptrs;
+ ng->s.len = gen_ptrs;
return ng;
}
@@ -1228,7 +1231,11 @@ static int register_pernet_operations(struct list_head *list,
if (error < 0)
return error;
*ops->id = error;
- max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1);
+ /* This does not require READ_ONCE as writers already hold
+ * pernet_ops_rwsem. But WRITE_ONCE is needed to protect
+ * net_alloc_generic.
+ */
+ WRITE_ONCE(max_gen_ptrs, max(max_gen_ptrs, *ops->id + 1));
}
error = __register_pernet_operations(list, ops);
if (error) {
--
2.34.1