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From:   Gopal Tiwari <gopalkrishna.tiwari@gmail.com>
To:     linux-bluetooth@vger.kernel.org
Cc:     luiz.dentz@gmail.com, gtiwari@redhat.com
Subject: [Bluez 10/13] Fixing use after free in src/device.c
Date:   Mon, 30 May 2022 13:42:06 +0530
Message-Id: <20220530081209.560465-11-gopalkrishna.tiwari@gmail.com>
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From: Gopal Tiwari <gtiwari@redhat.com>

Following traces reported by covirty tool

Error: USE_AFTER_FREE (CWE-416):
bluez-5.64/src/device.c:2962: path: Condition "!dbus_message_get_args(msg, NULL, 0 /* (int)0 */)", taking false branch.
bluez-5.64/src/device.c:2965: path: Condition "device->bonding", taking false branch.
bluez-5.64/src/device.c:2968: path: Condition "device->bredr_state.bonded", taking true branch.
bluez-5.64/src/device.c:2969: path: Falling through to end of if statement.
bluez-5.64/src/device.c:2977: path: Condition "state->bonded", taking false branch.
bluez-5.64/src/device.c:2983: path: Condition "agent", taking true branch.
bluez-5.64/src/device.c:2984: path: Falling through to end of if statement.
bluez-5.64/src/device.c:2990: path: Condition "agent", taking true branch.
bluez-5.64/src/device.c:3005: path: Condition "bdaddr_type != 0", taking true branch.
bluez-5.64/src/device.c:3006: path: Condition "!state->connected", taking true branch.
bluez-5.64/src/device.c:3006: path: Condition "btd_le_connect_before_pairing()", taking true branch.
bluez-5.64/src/device.c:3007: freed_arg: "device_connect_le" frees "device->bonding".
bluez-5.64/src/device.c:3007: path: Falling through to end of if statement.
bluez-5.64/src/device.c:3012: path: Falling through to end of if statement.
bluez-5.64/src/device.c:3017: path: Condition "err < 0", taking true branch.
bluez-5.64/src/device.c:3018: double_free: Calling "bonding_request_free" frees pointer "device->bonding" which has already been freed.

Signed-off-by: Gopal Tiwari <gtiwari@redhat.com>
---
 src/device.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/device.c b/src/device.c
index 8dc12d026..a0e5d40db 100644
--- a/src/device.c
+++ b/src/device.c
@@ -2942,6 +2942,7 @@ static void bonding_request_free(struct bonding_req *bonding)
 		bonding->device->bonding = NULL;
 
 	g_free(bonding);
+	bonding = NULL;
 }
 
 static DBusMessage *pair_device(DBusConnection *conn, DBusMessage *msg,
-- 
2.26.2