net/tls: sleeping function from invalid context
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 <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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);