From df9d4a1780223c3ddd4bf0810079b5a75251554e Mon Sep 17 00:00:00 2001 From: Atul Gupta Date: Tue, 11 Dec 2018 02:20:09 -0800 Subject: 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: 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 Signed-off-by: David S. Miller --- net/tls/tls_main.c | 36 +++++++++++++++++++++++------------- 1 file changed, 23 insertions(+), 13 deletions(-) (limited to 'net/tls') diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c index 492080306edc..1428bd74638c 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 @@ out: 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); -- cgit v1.2.3-59-g8ed1b