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From:   Tedd Ho-Jeong An <hj.tedd.an@gmail.com>
To:     linux-bluetooth@vger.kernel.org
Subject: [BlueZ PATCH] monitor/sdp: Fixes out-of-bounds array access
Date:   Wed,  9 Feb 2022 22:09:17 -0800
Message-Id: <20220210060917.50156-1-hj.tedd.an@gmail.com>
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From: Tedd Ho-Jeong An <tedd.an@intel.com>

This patch fixes the out-of-bounds array access caught by the ASAN.

monitor/sdp.c:497:19: runtime error: index 8 out of bounds for type 'cont_data [8]'
=================================================================
==4180==ERROR: AddressSanitizer: global-buffer-overflow on address 0x7fe2d271a542 at pc 0x7fe2d174a57d bp 0x7ffc6dcac1d0 sp 0x7ffc6dcab978
WRITE of size 9 at 0x7fe2d271a542 thread T0
    #0 0x7fe2d174a57c  (/lib/x86_64-linux-gnu/libasan.so.5+0x9b57c)
    #1 0x7fe2d23bae85 in search_attr_rsp monitor/sdp.c:692
    #2 0x7fe2d23be3f1 in sdp_packet monitor/sdp.c:771
    #3 0x7fe2d23b004c in l2cap_frame monitor/l2cap.c:3247
    #4 0x7fe2d23b3d9c in l2cap_packet monitor/l2cap.c:3312
    #5 0x7fe2d237d5c3 in packet_hci_acldata monitor/packet.c:11638
    #6 0x7fe2d2381876 in packet_monitor monitor/packet.c:3967
    #7 0x7fe2d230b285 in data_callback monitor/control.c:973
    #8 0x7fe2d2447029 in mainloop_run src/shared/mainloop.c:106
    #9 0x7fe2d2449306 in mainloop_run_with_signal src/shared/mainloop-notify.c:188
    #10 0x7fe2d230324a in main monitor/main.c:290
    #11 0x7fe2d0b440b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
    #12 0x7fe2d2303b7d in _start (/home/han1/work/dev/bluez/monitor/btmon+0x1dbb7d)

0x7fe2d271a542 is located 30 bytes to the left of global variable 'tid_list' defined in 'monitor/sdp.c:43:24' (0x7fe2d271a560) of size 384
0x7fe2d271a542 is located 2 bytes to the right of global variable 'cont_list' defined in 'monitor/sdp.c:424:25' (0x7fe2d271a400) of size 320
SUMMARY: AddressSanitizer: global-buffer-overflow (/lib/x86_64-linux-gnu/libasan.so.5+0x9b57c)
...
==4180==ABORTING
---
 monitor/sdp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/monitor/sdp.c b/monitor/sdp.c
index 10bc0a121..daf9a9da8 100644
--- a/monitor/sdp.c
+++ b/monitor/sdp.c
@@ -494,7 +494,7 @@ static void handle_continuation(struct tid_data *tid, bool nested,
 		cont_list[n].data = NULL;
 		cont_list[n].size = 0;
 	} else
-		memcpy(cont_list[i].cont, data + bytes, data[bytes] + 1);
+		memcpy(cont_list[n].cont, data + bytes, data[bytes] + 1);
 }
 
 static uint16_t common_rsp(const struct l2cap_frame *frame,
-- 
2.25.1