linux-kernel - [PATCH v2 02/17] firewire: core: use guard macro to maintain the list of card

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240805085408.251763-3-o-takashi@sakamocchi.jp>
Date: Mon,  5 Aug 2024 17:53:53 +0900
From: Takashi Sakamoto <o-takashi@...amocchi.jp>
To: linux1394-devel@...ts.sourceforge.net
Cc: linux-kernel@...r.kernel.org
Subject: [PATCH v2 02/17] firewire: core: use guard macro to maintain the list of card

The core function maintains registered cards by list. The concurrent
access to the list is protected by static mutex.

This commit uses guard macro to maintain the mutex.

Signed-off-by: Takashi Sakamoto <o-takashi@...amocchi.jp>
---
 drivers/firewire/core-card.c | 44 +++++++++++++++---------------------
 1 file changed, 18 insertions(+), 26 deletions(-)

diff --git a/drivers/firewire/core-card.c b/drivers/firewire/core-card.c
index f8b99dd6cd82..79a5b19e9d18 100644
--- a/drivers/firewire/core-card.c
+++ b/drivers/firewire/core-card.c
@@ -168,7 +168,6 @@ static size_t required_space(struct fw_descriptor *desc)
 int fw_core_add_descriptor(struct fw_descriptor *desc)
 {
 	size_t i;
-	int ret;
 
 	/*
 	 * Check descriptor is valid; the length of all blocks in the
@@ -182,29 +181,25 @@ int fw_core_add_descriptor(struct fw_descriptor *desc)
 	if (i != desc->length)
 		return -EINVAL;
 
-	mutex_lock(&card_mutex);
+	guard(mutex)(&card_mutex);
 
-	if (config_rom_length + required_space(desc) > 256) {
-		ret = -EBUSY;
-	} else {
-		list_add_tail(&desc->link, &descriptor_list);
-		config_rom_length += required_space(desc);
-		descriptor_count++;
-		if (desc->immediate > 0)
-			descriptor_count++;
-		update_config_roms();
-		ret = 0;
-	}
+	if (config_rom_length + required_space(desc) > 256)
+		return -EBUSY;
 
-	mutex_unlock(&card_mutex);
+	list_add_tail(&desc->link, &descriptor_list);
+	config_rom_length += required_space(desc);
+	descriptor_count++;
+	if (desc->immediate > 0)
+		descriptor_count++;
+	update_config_roms();
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(fw_core_add_descriptor);
 
 void fw_core_remove_descriptor(struct fw_descriptor *desc)
 {
-	mutex_lock(&card_mutex);
+	guard(mutex)(&card_mutex);
 
 	list_del(&desc->link);
 	config_rom_length -= required_space(desc);
@@ -212,8 +207,6 @@ void fw_core_remove_descriptor(struct fw_descriptor *desc)
 	if (desc->immediate > 0)
 		descriptor_count--;
 	update_config_roms();
-
-	mutex_unlock(&card_mutex);
 }
 EXPORT_SYMBOL(fw_core_remove_descriptor);
 
@@ -587,16 +580,16 @@ int fw_card_add(struct fw_card *card,
 	card->link_speed = link_speed;
 	card->guid = guid;
 
-	mutex_lock(&card_mutex);
+	guard(mutex)(&card_mutex);
 
 	generate_config_rom(card, tmp_config_rom);
 	ret = card->driver->enable(card, tmp_config_rom, config_rom_length);
-	if (ret == 0)
-		list_add_tail(&card->link, &card_list);
+	if (ret < 0)
+		return ret;
 
-	mutex_unlock(&card_mutex);
+	list_add_tail(&card->link, &card_list);
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(fw_card_add);
 
@@ -720,9 +713,8 @@ void fw_core_remove_card(struct fw_card *card)
 				     PHY_LINK_ACTIVE | PHY_CONTENDER, 0);
 	fw_schedule_bus_reset(card, false, true);
 
-	mutex_lock(&card_mutex);
-	list_del_init(&card->link);
-	mutex_unlock(&card_mutex);
+	scoped_guard(mutex, &card_mutex)
+		list_del_init(&card->link);
 
 	/* Switch off most of the card driver interface. */
 	dummy_driver.free_iso_context	= card->driver->free_iso_context;
-- 
2.43.0