From 552aa585faff19ceead7aa840d4ce11830ce34a9 Mon Sep 17 00:00:00 2001 From: Elena Reshetova Date: Tue, 28 Mar 2017 11:56:42 +0300 Subject: [PATCH] hostap: convert hostap_cmd_queue.usecnt from atomic_t to refcount_t refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: Kalle Valo --- drivers/net/wireless/intersil/hostap/hostap_hw.c | 12 ++++++------ drivers/net/wireless/intersil/hostap/hostap_wlan.h | 3 ++- 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/net/wireless/intersil/hostap/hostap_hw.c b/drivers/net/wireless/intersil/hostap/hostap_hw.c index 04dfd040a650..d4f0b730796e 100644 --- a/drivers/net/wireless/intersil/hostap/hostap_hw.c +++ b/drivers/net/wireless/intersil/hostap/hostap_hw.c @@ -190,7 +190,7 @@ static inline void __hostap_cmd_queue_free(local_info_t *local, } } - if (atomic_dec_and_test(&entry->usecnt) && entry->del_req) + if (refcount_dec_and_test(&entry->usecnt) && entry->del_req) kfree(entry); } @@ -228,7 +228,7 @@ static void prism2_clear_cmd_queue(local_info_t *local) spin_lock_irqsave(&local->cmdlock, flags); list_for_each_safe(ptr, n, &local->cmd_queue) { entry = list_entry(ptr, struct hostap_cmd_queue, list); - atomic_inc(&entry->usecnt); + refcount_inc(&entry->usecnt); printk(KERN_DEBUG "%s: removed pending cmd_queue entry " "(type=%d, cmd=0x%04x, param0=0x%04x)\n", local->dev->name, entry->type, entry->cmd, @@ -350,7 +350,7 @@ static int hfa384x_cmd(struct net_device *dev, u16 cmd, u16 param0, if (entry == NULL) return -ENOMEM; - atomic_set(&entry->usecnt, 1); + refcount_set(&entry->usecnt, 1); entry->type = CMD_SLEEP; entry->cmd = cmd; entry->param0 = param0; @@ -516,7 +516,7 @@ static int hfa384x_cmd_callback(struct net_device *dev, u16 cmd, u16 param0, if (entry == NULL) return -ENOMEM; - atomic_set(&entry->usecnt, 1); + refcount_set(&entry->usecnt, 1); entry->type = CMD_CALLBACK; entry->cmd = cmd; entry->param0 = param0; @@ -666,7 +666,7 @@ static void prism2_cmd_ev(struct net_device *dev) if (!list_empty(&local->cmd_queue)) { entry = list_entry(local->cmd_queue.next, struct hostap_cmd_queue, list); - atomic_inc(&entry->usecnt); + refcount_inc(&entry->usecnt); list_del_init(&entry->list); local->cmd_queue_len--; @@ -718,7 +718,7 @@ static void prism2_cmd_ev(struct net_device *dev) entry = NULL; } if (entry) - atomic_inc(&entry->usecnt); + refcount_inc(&entry->usecnt); } spin_unlock(&local->cmdlock); diff --git a/drivers/net/wireless/intersil/hostap/hostap_wlan.h b/drivers/net/wireless/intersil/hostap/hostap_wlan.h index ca25283e1c92..5352adb94d50 100644 --- a/drivers/net/wireless/intersil/hostap/hostap_wlan.h +++ b/drivers/net/wireless/intersil/hostap/hostap_wlan.h @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -557,7 +558,7 @@ struct hostap_cmd_queue { u16 resp0, res; volatile int issued, issuing; - atomic_t usecnt; + refcount_t usecnt; int del_req; }; -- 2.20.1