Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: fix crash in automatic module unloading
  firewire: potentially invalid pointers used in fw_card_bm_work
  firewire: fw-sbp2: better fix for NULL pointer dereference in scsi_remove_device

6 files changed, 97 insertions, 54 deletions

diff --git a/drivers/firewire/fw-card.c b/drivers/firewire/fw-card.c
index 3e97199..a034627 100644
--- a/drivers/firewire/fw-card.c
+++ b/drivers/firewire/fw-card.c
@@ -18,6 +18,7 @@
 
 #include <linux/module.h>
 #include <linux/errno.h>
+#include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/mutex.h>
 #include <linux/crc-itu-t.h>
@@ -214,17 +215,29 @@ static void
 fw_card_bm_work(struct work_struct *work)
 {
 	struct fw_card *card = container_of(work, struct fw_card, work.work);
-	struct fw_device *root;
+	struct fw_device *root_device;
+	struct fw_node *root_node, *local_node;
 	struct bm_data bmd;
 	unsigned long flags;
 	int root_id, new_root_id, irm_id, gap_count, generation, grace;
 	int do_reset = 0;
 
 	spin_lock_irqsave(&card->lock, flags);
+	local_node = card->local_node;
+	root_node  = card->root_node;
+
+	if (local_node == NULL) {
+		spin_unlock_irqrestore(&card->lock, flags);
+		return;
+	}
+	fw_node_get(local_node);
+	fw_node_get(root_node);
 
 	generation = card->generation;
-	root = card->root_node->data;
-	root_id = card->root_node->node_id;
+	root_device = root_node->data;
+	if (root_device)
+		fw_device_get(root_device);
+	root_id = root_node->node_id;
 	grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 10));
 
 	if (card->bm_generation + 1 == generation ||
@@ -243,14 +256,14 @@ fw_card_bm_work(struct work_struct *work)
 
 		irm_id = card->irm_node->node_id;
 		if (!card->irm_node->link_on) {
-			new_root_id = card->local_node->node_id;
+			new_root_id = local_node->node_id;
 			fw_notify("IRM has link off, making local node (%02x) root.\n",
 				  new_root_id);
 			goto pick_me;
 		}
 
 		bmd.lock.arg = cpu_to_be32(0x3f);
-		bmd.lock.data = cpu_to_be32(card->local_node->node_id);
+		bmd.lock.data = cpu_to_be32(local_node->node_id);
 
 		spin_unlock_irqrestore(&card->lock, flags);
 
@@ -267,12 +280,12 @@ fw_card_bm_work(struct work_struct *work)
 			 * Another bus reset happened. Just return,
 			 * the BM work has been rescheduled.
 			 */
-			return;
+			goto out;
 		}
 
 		if (bmd.rcode == RCODE_COMPLETE && bmd.old != 0x3f)
 			/* Somebody else is BM, let them do the work. */
-			return;
+			goto out;
 
 		spin_lock_irqsave(&card->lock, flags);
 		if (bmd.rcode != RCODE_COMPLETE) {
@@ -282,7 +295,7 @@ fw_card_bm_work(struct work_struct *work)
 			 * do a bus reset and pick the local node as
 			 * root, and thus, IRM.
 			 */
-			new_root_id = card->local_node->node_id;
+			new_root_id = local_node->node_id;
 			fw_notify("BM lock failed, making local node (%02x) root.\n",
 				  new_root_id);
 			goto pick_me;
@@ -295,7 +308,7 @@ fw_card_bm_work(struct work_struct *work)
 		 */
 		spin_unlock_irqrestore(&card->lock, flags);
 		schedule_delayed_work(&card->work, DIV_ROUND_UP(HZ, 10));
-		return;
+		goto out;
 	}
 
 	/*
@@ -305,20 +318,20 @@ fw_card_bm_work(struct work_struct *work)
 	 */
 	card->bm_generation = generation;
 
-	if (root == NULL) {
+	if (root_device == NULL) {
 		/*
 		 * Either link_on is false, or we failed to read the
 		 * config rom.  In either case, pick another root.
 		 */
-		new_root_id = card->local_node->node_id;
-	} else if (atomic_read(&root->state) != FW_DEVICE_RUNNING) {
+		new_root_id = local_node->node_id;
+	} else if (atomic_read(&root_device->state) != FW_DEVICE_RUNNING) {
 		/*
 		 * If we haven't probed this device yet, bail out now
 		 * and let's try again once that's done.
 		 */
 		spin_unlock_irqrestore(&card->lock, flags);
-		return;
-	} else if (root->config_rom[2] & BIB_CMC) {
+		goto out;
+	} else if (root_device->config_rom[2] & BIB_CMC) {
 		/*
 		 * FIXME: I suppose we should set the cmstr bit in the
 		 * STATE_CLEAR register of this node, as described in
@@ -332,7 +345,7 @@ fw_card_bm_work(struct work_struct *work)
 		 * successfully read the config rom, but it's not
 		 * cycle master capable.
 		 */
-		new_root_id = card->local_node->node_id;
+		new_root_id = local_node->node_id;
 	}
 
  pick_me:
@@ -341,8 +354,8 @@ fw_card_bm_work(struct work_struct *work)
 	 * the typically much larger 1394b beta repeater delays though.
 	 */
 	if (!card->beta_repeaters_present &&
-	    card->root_node->max_hops < ARRAY_SIZE(gap_count_table))
-		gap_count = gap_count_table[card->root_node->max_hops];
+	    root_node->max_hops < ARRAY_SIZE(gap_count_table))
+		gap_count = gap_count_table[root_node->max_hops];
 	else
 		gap_count = 63;
 
@@ -364,6 +377,11 @@ fw_card_bm_work(struct work_struct *work)
 		fw_send_phy_config(card, new_root_id, generation, gap_count);
 		fw_core_initiate_bus_reset(card, 1);
 	}
+ out:
+	if (root_device)
+		fw_device_put(root_device);
+	fw_node_put(root_node);
+	fw_node_put(local_node);
 }
 
 static void
@@ -381,6 +399,7 @@ fw_card_initialize(struct fw_card *card, const struct fw_card_driver *driver,
 	static atomic_t index = ATOMIC_INIT(-1);
 
 	kref_init(&card->kref);
+	atomic_set(&card->device_count, 0);
 	card->index = atomic_inc_return(&index);
 	card->driver = driver;
 	card->device = device;
@@ -511,8 +530,14 @@ fw_core_remove_card(struct fw_card *card)
 	card->driver = &dummy_driver;
 
 	fw_destroy_nodes(card);
-	flush_scheduled_work();
+	/*
+	 * Wait for all device workqueue jobs to finish.  Otherwise the
+	 * firewire-core module could be unloaded before the jobs ran.
+	 */
+	while (atomic_read(&card->device_count) > 0)
+		msleep(100);
 
+	cancel_delayed_work_sync(&card->work);
 	fw_flush_transactions(card);
 	del_timer_sync(&card->flush_timer);
 
diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index 2ab13e0..870125a 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -150,21 +150,10 @@ struct bus_type fw_bus_type = {
 };
 EXPORT_SYMBOL(fw_bus_type);
 
-struct fw_device *fw_device_get(struct fw_device *device)
-{
-	get_device(&device->device);
-
-	return device;
-}
-
-void fw_device_put(struct fw_device *device)
-{
-	put_device(&device->device);
-}
-
 static void fw_device_release(struct device *dev)
 {
 	struct fw_device *device = fw_device(dev);
+	struct fw_card *card = device->card;
 	unsigned long flags;
 
 	/*
@@ -176,9 +165,9 @@ static void fw_device_release(struct device *dev)
 	spin_unlock_irqrestore(&device->card->lock, flags);
 
 	fw_node_put(device->node);
-	fw_card_put(device->card);
 	kfree(device->config_rom);
 	kfree(device);
+	atomic_dec(&card->device_count);
 }
 
 int fw_device_enable_phys_dma(struct fw_device *device)
@@ -668,7 +657,8 @@ static void fw_device_init(struct work_struct *work)
 	 */
 
 	if (read_bus_info_block(device, device->generation) < 0) {
-		if (device->config_rom_retries < MAX_RETRIES) {
+		if (device->config_rom_retries < MAX_RETRIES &&
+		    atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
 			device->config_rom_retries++;
 			schedule_delayed_work(&device->work, RETRY_DELAY);
 		} else {
@@ -805,7 +795,8 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 		 */
 		device_initialize(&device->device);
 		atomic_set(&device->state, FW_DEVICE_INITIALIZING);
-		device->card = fw_card_get(card);
+		atomic_inc(&card->device_count);
+		device->card = card;
 		device->node = fw_node_get(node);
 		device->node_id = node->node_id;
 		device->generation = card->generation;
diff --git a/drivers/firewire/fw-device.h b/drivers/firewire/fw-device.h
index 43808c0..78ecd39 100644
--- a/drivers/firewire/fw-device.h
+++ b/drivers/firewire/fw-device.h
@@ -76,9 +76,21 @@ fw_device_is_shutdown(struct fw_device *device)
 	return atomic_read(&device->state) == FW_DEVICE_SHUTDOWN;
 }
 
-struct fw_device *fw_device_get(struct fw_device *device);
+static inline struct fw_device *
+fw_device_get(struct fw_device *device)
+{
+	get_device(&device->device);
+
+	return device;
+}
+
+static inline void
+fw_device_put(struct fw_device *device)
+{
+	put_device(&device->device);
+}
+
 struct fw_device *fw_device_get_by_devt(dev_t devt);
-void fw_device_put(struct fw_device *device);
 int fw_device_enable_phys_dma(struct fw_device *device);
 
 void fw_device_cdev_update(struct fw_device *device);
diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index 5259491..03069a4 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -122,7 +122,6 @@ static const char sbp2_driver_name[] = "sbp2";
 struct sbp2_logical_unit {
 	struct sbp2_target *tgt;
 	struct list_head link;
-	struct scsi_device *sdev;
 	struct fw_address_handler address_handler;
 	struct list_head orb_list;
 
@@ -139,6 +138,7 @@ struct sbp2_logical_unit {
 	int generation;
 	int retries;
 	struct delayed_work work;
+	bool has_sdev;
 	bool blocked;
 };
 
@@ -751,20 +751,34 @@ static void sbp2_unblock(struct sbp2_target *tgt)
 	scsi_unblock_requests(shost);
 }
 
+static int sbp2_lun2int(u16 lun)
+{
+	struct scsi_lun eight_bytes_lun;
+
+	memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
+	eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
+	eight_bytes_lun.scsi_lun[1] = lun & 0xff;
+
+	return scsilun_to_int(&eight_bytes_lun);
+}
+
 static void sbp2_release_target(struct kref *kref)
 {
 	struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 	struct sbp2_logical_unit *lu, *next;
 	struct Scsi_Host *shost =
 		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
+	struct scsi_device *sdev;
+	struct fw_device *device = fw_device(tgt->unit->device.parent);
 
 	/* prevent deadlocks */
 	sbp2_unblock(tgt);
 
 	list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
-		if (lu->sdev) {
-			scsi_remove_device(lu->sdev);
-			scsi_device_put(lu->sdev);
+		sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
+		if (sdev) {
+			scsi_remove_device(sdev);
+			scsi_device_put(sdev);
 		}
 		sbp2_send_management_orb(lu, tgt->node_id, lu->generation,
 				SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
@@ -778,6 +792,7 @@ static void sbp2_release_target(struct kref *kref)
 
 	put_device(&tgt->unit->device);
 	scsi_host_put(shost);
+	fw_device_put(device);
 }
 
 static struct workqueue_struct *sbp2_wq;
@@ -807,7 +822,6 @@ static void sbp2_login(struct work_struct *work)
 	struct fw_device *device = fw_device(tgt->unit->device.parent);
 	struct Scsi_Host *shost;
 	struct scsi_device *sdev;
-	struct scsi_lun eight_bytes_lun;
 	struct sbp2_login_response response;
 	int generation, node_id, local_node_id;
 
@@ -820,7 +834,7 @@ static void sbp2_login(struct work_struct *work)
 	local_node_id = device->card->node_id;
 
 	/* If this is a re-login attempt, log out, or we might be rejected. */
-	if (lu->sdev)
+	if (lu->has_sdev)
 		sbp2_send_management_orb(lu, device->node_id, generation,
 				SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 
@@ -859,7 +873,7 @@ static void sbp2_login(struct work_struct *work)
 	sbp2_agent_reset(lu);
 
 	/* This was a re-login. */
-	if (lu->sdev) {
+	if (lu->has_sdev) {
 		sbp2_cancel_orbs(lu);
 		sbp2_conditionally_unblock(lu);
 		goto out;
@@ -868,13 +882,8 @@ static void sbp2_login(struct work_struct *work)
 	if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 		ssleep(SBP2_INQUIRY_DELAY);
 
-	memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
-	eight_bytes_lun.scsi_lun[0] = (lu->lun >> 8) & 0xff;
-	eight_bytes_lun.scsi_lun[1] = lu->lun & 0xff;
 	shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
-
-	sdev = __scsi_add_device(shost, 0, 0,
-				 scsilun_to_int(&eight_bytes_lun), lu);
+	sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 	/*
 	 * FIXME:  We are unable to perform reconnects while in sbp2_login().
 	 * Therefore __scsi_add_device() will get into trouble if a bus reset
@@ -896,7 +905,8 @@ static void sbp2_login(struct work_struct *work)
 	}
 
 	/* No error during __scsi_add_device() */
-	lu->sdev = sdev;
+	lu->has_sdev = true;
+	scsi_device_put(sdev);
 	sbp2_allow_block(lu);
 	goto out;
 
@@ -934,11 +944,11 @@ static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 		return -ENOMEM;
 	}
 
-	lu->tgt  = tgt;
-	lu->sdev = NULL;
-	lu->lun  = lun_entry & 0xffff;
-	lu->retries = 0;
-	lu->blocked = false;
+	lu->tgt      = tgt;
+	lu->lun      = lun_entry & 0xffff;
+	lu->retries  = 0;
+	lu->has_sdev = false;
+	lu->blocked  = false;
 	++tgt->dont_block;
 	INIT_LIST_HEAD(&lu->orb_list);
 	INIT_DELAYED_WORK(&lu->work, sbp2_login);
@@ -1080,6 +1090,8 @@ static int sbp2_probe(struct device *dev)
 	if (scsi_add_host(shost, &unit->device) < 0)
 		goto fail_shost_put;
 
+	fw_device_get(device);
+
 	/* Initialize to values that won't match anything in our table. */
 	firmware_revision = 0xff000000;
 	model = 0xff000000;
diff --git a/drivers/firewire/fw-topology.c b/drivers/firewire/fw-topology.c
index 172c186..e47bb04 100644
--- a/drivers/firewire/fw-topology.c
+++ b/drivers/firewire/fw-topology.c
@@ -383,6 +383,7 @@ void fw_destroy_nodes(struct fw_card *card)
 	card->color++;
 	if (card->local_node != NULL)
 		for_each_fw_node(card, card->local_node, report_lost_node);
+	card->local_node = NULL;
 	spin_unlock_irqrestore(&card->lock, flags);
 }
 
diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h
index fa7967b..09cb728 100644
--- a/drivers/firewire/fw-transaction.h
+++ b/drivers/firewire/fw-transaction.h
@@ -26,6 +26,7 @@
 #include <linux/fs.h>
 #include <linux/dma-mapping.h>
 #include <linux/firewire-constants.h>
+#include <asm/atomic.h>
 
 #define TCODE_IS_READ_REQUEST(tcode)	(((tcode) & ~1) == 4)
 #define TCODE_IS_BLOCK_PACKET(tcode)	(((tcode) &  1) != 0)
@@ -219,6 +220,7 @@ extern struct bus_type fw_bus_type;
 struct fw_card {
 	const struct fw_card_driver *driver;
 	struct device *device;
+	atomic_t device_count;
 	struct kref kref;
 
 	int node_id;