HW unhash within mutex for registered tls devices cause sleep
when called from tcp_set_state for TCP_CLOSE. Release lock and
re-acquire after function call with ref count incr/dec.
defined kref and fp release for tls_device to ensure device
is not released outside lock.
BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:748
in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/7
INFO: lockdep is turned off.
CPU: 7 PID: 0 Comm: swapper/7 Tainted: G W O
Call Trace:
<IRQ>
dump_stack+0x5e/0x8b
___might_sleep+0x222/0x260
__mutex_lock+0x5c/0xa50
? vprintk_emit+0x1f3/0x440
? kmem_cache_free+0x22d/0x2a0
? tls_hw_unhash+0x2f/0x80
? printk+0x52/0x6e
? tls_hw_unhash+0x2f/0x80
tls_hw_unhash+0x2f/0x80
tcp_set_state+0x5f/0x180
tcp_done+0x2e/0xe0
tcp_rcv_state_process+0x92c/0xdd3
? lock_acquire+0xf5/0x1f0
? tcp_v4_rcv+0xa7c/0xbe0
? tcp_v4_do_rcv+0x70/0x1e0
Signed-off-by: Atul Gupta <[email protected]>
---
drivers/crypto/chelsio/chtls/chtls_main.c | 55 ++++++++++++++++++-------------
include/net/tls.h | 6 ++++
net/tls/tls_main.c | 36 ++++++++++++--------
3 files changed, 61 insertions(+), 36 deletions(-)
diff --git a/drivers/crypto/chelsio/chtls/chtls_main.c b/drivers/crypto/chelsio/chtls/chtls_main.c
index f472c51..db40ab6 100644
--- a/drivers/crypto/chelsio/chtls/chtls_main.c
+++ b/drivers/crypto/chelsio/chtls/chtls_main.c
@@ -149,6 +149,30 @@ static void chtls_destroy_hash(struct tls_device *dev, struct sock *sk)
chtls_stop_listen(sk);
}
+static void chtls_free_uld(struct chtls_dev *cdev)
+{
+ int i;
+
+ tls_unregister_device(&cdev->tlsdev);
+ kvfree(cdev->kmap.addr);
+ idr_destroy(&cdev->hwtid_idr);
+ for (i = 0; i < (1 << RSPQ_HASH_BITS); i++)
+ kfree_skb(cdev->rspq_skb_cache[i]);
+ kfree(cdev->lldi);
+ kfree_skb(cdev->askb);
+ kfree(cdev);
+}
+
+static inline void chtls_dev_release(struct kref *kref)
+{
+ struct chtls_dev *cdev;
+ struct tls_device *dev;
+
+ dev = container_of(kref, struct tls_device, kref);
+ cdev = to_chtls_dev(dev);
+ chtls_free_uld(cdev);
+}
+
static void chtls_register_dev(struct chtls_dev *cdev)
{
struct tls_device *tlsdev = &cdev->tlsdev;
@@ -159,15 +183,12 @@ static void chtls_register_dev(struct chtls_dev *cdev)
tlsdev->feature = chtls_inline_feature;
tlsdev->hash = chtls_create_hash;
tlsdev->unhash = chtls_destroy_hash;
- tls_register_device(&cdev->tlsdev);
+ tlsdev->release = chtls_dev_release;
+ kref_init(&tlsdev->kref);
+ tls_register_device(tlsdev);
cdev->cdev_state = CHTLS_CDEV_STATE_UP;
}
-static void chtls_unregister_dev(struct chtls_dev *cdev)
-{
- tls_unregister_device(&cdev->tlsdev);
-}
-
static void process_deferq(struct work_struct *task_param)
{
struct chtls_dev *cdev = container_of(task_param,
@@ -262,28 +283,16 @@ static void *chtls_uld_add(const struct cxgb4_lld_info *info)
return NULL;
}
-static void chtls_free_uld(struct chtls_dev *cdev)
-{
- int i;
-
- chtls_unregister_dev(cdev);
- kvfree(cdev->kmap.addr);
- idr_destroy(&cdev->hwtid_idr);
- for (i = 0; i < (1 << RSPQ_HASH_BITS); i++)
- kfree_skb(cdev->rspq_skb_cache[i]);
- kfree(cdev->lldi);
- kfree_skb(cdev->askb);
- kfree(cdev);
-}
-
static void chtls_free_all_uld(void)
{
struct chtls_dev *cdev, *tmp;
mutex_lock(&cdev_mutex);
list_for_each_entry_safe(cdev, tmp, &cdev_list, list) {
- if (cdev->cdev_state == CHTLS_CDEV_STATE_UP)
- chtls_free_uld(cdev);
+ if (cdev->cdev_state == CHTLS_CDEV_STATE_UP) {
+ list_del(&cdev->list);
+ kref_put(&cdev->tlsdev.kref, cdev->tlsdev.release);
+ }
}
mutex_unlock(&cdev_mutex);
}
@@ -304,7 +313,7 @@ static int chtls_uld_state_change(void *handle, enum cxgb4_state new_state)
mutex_lock(&cdev_mutex);
list_del(&cdev->list);
mutex_unlock(&cdev_mutex);
- chtls_free_uld(cdev);
+ kref_put(&cdev->tlsdev.kref, cdev->tlsdev.release);
break;
default:
break;
diff --git a/include/net/tls.h b/include/net/tls.h
index bab5627..3cbcd12 100644
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -76,6 +76,10 @@
*
* void (*unhash)(struct tls_device *device, struct sock *sk);
* This function cleans listen state set by Inline TLS driver
+ *
+ * void (*release)(struct kref *kref);
+ * Release the registered device and allocated resources
+ * @kref: Number of reference to tls_device
*/
struct tls_device {
char name[TLS_DEVICE_NAME_MAX];
@@ -83,6 +87,8 @@ struct tls_device {
int (*feature)(struct tls_device *device);
int (*hash)(struct tls_device *device, struct sock *sk);
void (*unhash)(struct tls_device *device, struct sock *sk);
+ void (*release)(struct kref *kref);
+ struct kref kref;
};
enum {
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index 4920803..1428bd7 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -56,7 +56,7 @@ enum {
static struct proto *saved_tcpv6_prot;
static DEFINE_MUTEX(tcpv6_prot_mutex);
static LIST_HEAD(device_list);
-static DEFINE_MUTEX(device_mutex);
+static DEFINE_SPINLOCK(device_spinlock);
static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
static struct proto_ops tls_sw_proto_ops;
@@ -555,7 +555,7 @@ static int tls_hw_prot(struct sock *sk)
struct tls_device *dev;
int rc = 0;
- mutex_lock(&device_mutex);
+ spin_lock_bh(&device_spinlock);
list_for_each_entry(dev, &device_list, dev_list) {
if (dev->feature && dev->feature(dev)) {
ctx = create_ctx(sk);
@@ -573,7 +573,7 @@ static int tls_hw_prot(struct sock *sk)
}
}
out:
- mutex_unlock(&device_mutex);
+ spin_unlock_bh(&device_spinlock);
return rc;
}
@@ -582,12 +582,17 @@ static void tls_hw_unhash(struct sock *sk)
struct tls_context *ctx = tls_get_ctx(sk);
struct tls_device *dev;
- mutex_lock(&device_mutex);
+ spin_lock_bh(&device_spinlock);
list_for_each_entry(dev, &device_list, dev_list) {
- if (dev->unhash)
+ if (dev->unhash) {
+ kref_get(&dev->kref);
+ spin_unlock_bh(&device_spinlock);
dev->unhash(dev, sk);
+ kref_put(&dev->kref, dev->release);
+ spin_lock_bh(&device_spinlock);
+ }
}
- mutex_unlock(&device_mutex);
+ spin_unlock_bh(&device_spinlock);
ctx->unhash(sk);
}
@@ -598,12 +603,17 @@ static int tls_hw_hash(struct sock *sk)
int err;
err = ctx->hash(sk);
- mutex_lock(&device_mutex);
+ spin_lock_bh(&device_spinlock);
list_for_each_entry(dev, &device_list, dev_list) {
- if (dev->hash)
+ if (dev->hash) {
+ kref_get(&dev->kref);
+ spin_unlock_bh(&device_spinlock);
err |= dev->hash(dev, sk);
+ kref_put(&dev->kref, dev->release);
+ spin_lock_bh(&device_spinlock);
+ }
}
- mutex_unlock(&device_mutex);
+ spin_unlock_bh(&device_spinlock);
if (err)
tls_hw_unhash(sk);
@@ -699,17 +709,17 @@ static int tls_init(struct sock *sk)
void tls_register_device(struct tls_device *device)
{
- mutex_lock(&device_mutex);
+ spin_lock_bh(&device_spinlock);
list_add_tail(&device->dev_list, &device_list);
- mutex_unlock(&device_mutex);
+ spin_unlock_bh(&device_spinlock);
}
EXPORT_SYMBOL(tls_register_device);
void tls_unregister_device(struct tls_device *device)
{
- mutex_lock(&device_mutex);
+ spin_lock_bh(&device_spinlock);
list_del(&device->dev_list);
- mutex_unlock(&device_mutex);
+ spin_unlock_bh(&device_spinlock);
}
EXPORT_SYMBOL(tls_unregister_device);
--
1.8.3.1
From: Atul Gupta <[email protected]>
Date: Tue, 11 Dec 2018 02:20:09 -0800
> HW unhash within mutex for registered tls devices cause sleep
> when called from tcp_set_state for TCP_CLOSE. Release lock and
> re-acquire after function call with ref count incr/dec.
> defined kref and fp release for tls_device to ensure device
> is not released outside lock.
...
> Signed-off-by: Atul Gupta <[email protected]>
Applied.