From 2512e40e48d21d8bac09f7e91d2c3ceb2d3b50b2 Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Wed, 22 Aug 2018 12:08:13 -0500 Subject: ipmi: Rework SMI registration failure There were certain situations where ipmi_register_smi() would return a failure, but the interface would still be registered and would need to be unregistered. This is obviously a bad design and resulted in an oops in certain failure cases. If the interface is started up in ipmi_register_smi(), then an error occurs, shut down the interface there so the cleanup can be done properly. Fix the various smi users, too. Signed-off-by: Corey Minyard Reported-by: Justin Ernst Tested-by: Justin Ernst Cc: Andrew Banman Cc: Russ Anderson Cc: # 4.18.x --- drivers/char/ipmi/ipmi_msghandler.c | 53 +++++++++++++++++++++---------------- drivers/char/ipmi/ipmi_si_intf.c | 17 +++--------- drivers/char/ipmi/ipmi_ssif.c | 13 +++------ 3 files changed, 37 insertions(+), 46 deletions(-) (limited to 'drivers/char/ipmi') diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index 51832b8a2c62..7fc9612070a1 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -3381,39 +3381,45 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers, rv = handlers->start_processing(send_info, intf); if (rv) - goto out; + goto out_err; rv = __bmc_get_device_id(intf, NULL, &id, NULL, NULL, i); if (rv) { dev_err(si_dev, "Unable to get the device id: %d\n", rv); - goto out; + goto out_err_started; } mutex_lock(&intf->bmc_reg_mutex); rv = __scan_channels(intf, &id); mutex_unlock(&intf->bmc_reg_mutex); + if (rv) + goto out_err_bmc_reg; - out: - if (rv) { - ipmi_bmc_unregister(intf); - list_del_rcu(&intf->link); - mutex_unlock(&ipmi_interfaces_mutex); - synchronize_srcu(&ipmi_interfaces_srcu); - cleanup_srcu_struct(&intf->users_srcu); - kref_put(&intf->refcount, intf_free); - } else { - /* - * Keep memory order straight for RCU readers. Make - * sure everything else is committed to memory before - * setting intf_num to mark the interface valid. - */ - smp_wmb(); - intf->intf_num = i; - mutex_unlock(&ipmi_interfaces_mutex); + /* + * Keep memory order straight for RCU readers. Make + * sure everything else is committed to memory before + * setting intf_num to mark the interface valid. + */ + smp_wmb(); + intf->intf_num = i; + mutex_unlock(&ipmi_interfaces_mutex); - /* After this point the interface is legal to use. */ - call_smi_watchers(i, intf->si_dev); - } + /* After this point the interface is legal to use. */ + call_smi_watchers(i, intf->si_dev); + + return 0; + + out_err_bmc_reg: + ipmi_bmc_unregister(intf); + out_err_started: + if (intf->handlers->shutdown) + intf->handlers->shutdown(intf->send_info); + out_err: + list_del_rcu(&intf->link); + mutex_unlock(&ipmi_interfaces_mutex); + synchronize_srcu(&ipmi_interfaces_srcu); + cleanup_srcu_struct(&intf->users_srcu); + kref_put(&intf->refcount, intf_free); return rv; } @@ -3504,7 +3510,8 @@ void ipmi_unregister_smi(struct ipmi_smi *intf) } srcu_read_unlock(&intf->users_srcu, index); - intf->handlers->shutdown(intf->send_info); + if (intf->handlers->shutdown) + intf->handlers->shutdown(intf->send_info); cleanup_smi_msgs(intf); diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c index 90ec010bffbd..5faa917df1b6 100644 --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -2083,18 +2083,9 @@ static int try_smi_init(struct smi_info *new_smi) si_to_str[new_smi->io.si_type]); WARN_ON(new_smi->io.dev->init_name != NULL); - kfree(init_name); - - return 0; - -out_err: - if (new_smi->intf) { - ipmi_unregister_smi(new_smi->intf); - new_smi->intf = NULL; - } + out_err: kfree(init_name); - return rv; } @@ -2227,6 +2218,8 @@ static void shutdown_smi(void *send_info) kfree(smi_info->si_sm); smi_info->si_sm = NULL; + + smi_info->intf = NULL; } /* @@ -2240,10 +2233,8 @@ static void cleanup_one_si(struct smi_info *smi_info) list_del(&smi_info->link); - if (smi_info->intf) { + if (smi_info->intf) ipmi_unregister_smi(smi_info->intf); - smi_info->intf = NULL; - } if (smi_info->pdev) { if (smi_info->pdev_registered) diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c index 18e4650c233b..c12edc8e91df 100644 --- a/drivers/char/ipmi/ipmi_ssif.c +++ b/drivers/char/ipmi/ipmi_ssif.c @@ -1214,18 +1214,11 @@ static void shutdown_ssif(void *send_info) complete(&ssif_info->wake_thread); kthread_stop(ssif_info->thread); } - - /* - * No message can be outstanding now, we have removed the - * upper layer and it permitted us to do so. - */ - kfree(ssif_info); } static int ssif_remove(struct i2c_client *client) { struct ssif_info *ssif_info = i2c_get_clientdata(client); - struct ipmi_smi *intf; struct ssif_addr_info *addr_info; if (!ssif_info) @@ -1235,9 +1228,7 @@ static int ssif_remove(struct i2c_client *client) * After this point, we won't deliver anything asychronously * to the message handler. We can unregister ourself. */ - intf = ssif_info->intf; - ssif_info->intf = NULL; - ipmi_unregister_smi(intf); + ipmi_unregister_smi(ssif_info->intf); list_for_each_entry(addr_info, &ssif_infos, link) { if (addr_info->client == client) { @@ -1246,6 +1237,8 @@ static int ssif_remove(struct i2c_client *client) } } + kfree(ssif_info); + return 0; } -- cgit v1.2.3