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 3e9719948a8e..a03462750b95 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 2ab13e0f3469..870125a3638e 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 43808c02793e..78ecd3991b7f 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 5259491580fc..03069a454c07 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 172c1867e9aa..e47bb040197a 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 fa7967b57408..09cb72870454 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;