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From:   Tedd Ho-Jeong An <hj.tedd.an@gmail.com>
To:     linux-bluetooth@vger.kernel.org
Subject: [BlueZ PATCH 2/4] device: Fix the reusing gerror without re-initialization
Date:   Thu, 10 Feb 2022 16:18:38 -0800
Message-Id: <20220211001840.22566-2-hj.tedd.an@gmail.com>
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From: Tedd Ho-Jeong An <tedd.an@intel.com>

When the GError variable is freeed with g_error_free(), it is not set to
NULL and reusing the same variable again can cause the seg_fault because
it is still pointing the old memory address which is freed.

This patch relaces the g_error_free() to g_clear_error() which frees the
variable and set it to NULL if the variable is used in the function
again.

Fixes: 6a154cd08000b ("device: Fix unchecked return value")
---
 src/device.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/device.c b/src/device.c
index 6d29eb896..6a7bdd207 100644
--- a/src/device.c
+++ b/src/device.c
@@ -543,7 +543,7 @@ void device_store_cached_name(struct btd_device *dev, const char *name)
 	if (!g_key_file_load_from_file(key_file, filename, 0, &gerr)) {
 		error("Unable to load key file from %s: (%s)", filename,
 								gerr->message);
-		g_error_free(gerr);
+		g_clear_error(&gerr);
 	}
 
 	data_old = g_key_file_to_data(key_file, &length_old, NULL);
@@ -556,7 +556,7 @@ void device_store_cached_name(struct btd_device *dev, const char *name)
 		if (!g_file_set_contents(filename, data, length, &gerr)) {
 			error("Unable set contents for %s: (%s)", filename,
 								gerr->message);
-			g_error_free(gerr);
+			g_clear_error(&gerr);
 		}
 	}
 	g_free(data);
@@ -592,7 +592,7 @@ static void device_store_cached_name_resolve(struct btd_device *dev)
 	if (!g_key_file_load_from_file(key_file, filename, 0, &gerr)) {
 		error("Unable to load key file from %s: (%s)", filename,
 								gerr->message);
-		g_error_free(gerr);
+		g_clear_error(&gerr);
 	}
 
 	failed_time = (uint64_t) dev->name_resolve_failed_time;
@@ -2666,7 +2666,7 @@ static void store_gatt_db(struct btd_device *device)
 	if (!g_key_file_load_from_file(key_file, filename, 0, &gerr)) {
 		error("Unable to load key file from %s: (%s)", filename,
 								gerr->message);
-		g_error_free(gerr);
+		g_clear_error(&gerr);
 	}
 
 	/* Remove current attributes since it might have changed */
@@ -3635,7 +3635,7 @@ static void load_att_info(struct btd_device *device, const char *local,
 	if (!g_key_file_load_from_file(key_file, filename, 0, &gerr)) {
 		error("Unable to load key file from %s: (%s)", filename,
 								gerr->message);
-		g_error_free(gerr);
+		g_clear_error(&gerr);
 	}
 	groups = g_key_file_get_groups(key_file, NULL);
 
@@ -6163,7 +6163,7 @@ void device_store_svc_chng_ccc(struct btd_device *device, uint8_t bdaddr_type,
 	if (!g_key_file_load_from_file(key_file, filename, 0, &gerr)) {
 		error("Unable to load key file from %s: (%s)", filename,
 								gerr->message);
-		g_error_free(gerr);
+		g_clear_error(&gerr);
 	}
 
 	/* for bonded devices this is done on every connection so limit writes
-- 
2.25.1