From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
[ Upstream commit 799acb9347915bfe4eac0ff2345b468f0a1ca207 ]
This fixes parsing of LTV entries when the length is 0.
Found with:
tools/mgmt-tester -s "Add Advertising - Success (ScRsp only)"
Add Advertising - Success (ScRsp only) - run Sending Add Advertising (0x003e) Test condition added, total 1 [ 11.004577] ================================================================== [ 11.005292] BUG: KASAN: slab-out-of-bounds in tlv_data_is_valid+0x87/0xe0 [ 11.005984] Read of size 1 at addr ffff888002c695b0 by task mgmt-tester/87 [ 11.006711] [ 11.007176] [ 11.007429] Allocated by task 87: [ 11.008151] [ 11.008438] The buggy address belongs to the object at ffff888002c69580 [ 11.008438] which belongs to the cache kmalloc-64 of size 64 [ 11.010526] The buggy address is located 48 bytes inside of [ 11.010526] 64-byte region [ffff888002c69580, ffff888002c695c0) [ 11.012423] The buggy address belongs to the page: [ 11.013291] [ 11.013544] Memory state around the buggy address: [ 11.014359] ffff888002c69480: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 11.015453] ffff888002c69500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 11.016232] >ffff888002c69580: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc [ 11.017010] ^ [ 11.017547] ffff888002c69600: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc [ 11.018296] ffff888002c69680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 11.019116] ==================================================================
Fixes: 2bb36870e8cb2 ("Bluetooth: Unify advertising instance flags check") Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/bluetooth/mgmt.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index f9be7f9084d6..023a98f7c992 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -7585,6 +7585,9 @@ static bool tlv_data_is_valid(struct hci_dev *hdev, u32 adv_flags, u8 *data, for (i = 0, cur_len = 0; i < len; i += (cur_len + 1)) { cur_len = data[i];
+ if (!cur_len) + continue; + if (data[i + 1] == EIR_FLAGS && (!is_adv_data || flags_managed(adv_flags))) return false;