From c70563620d4dac0227d261db0e34b24d48f62961 Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Wed, 13 Oct 2021 16:30:24 +0800 Subject: [PATCH] Bluetooth: mgmt: Fix slab-out-of-bounds in tlv_data_is_valid stable inclusion from stable-5.10.50 commit a2dcad039e45713c45168be53ebace6e1e0cfd0a bugzilla: 174522 https://gitee.com/openeuler/kernel/issues/I4DNFY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a2dcad039e45713c45168be53ebace6e1e0cfd0a -------------------------------- [ 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 Signed-off-by: Marcel Holtmann Signed-off-by: Sasha Levin Signed-off-by: Chen Jun Acked-by: Weilong Chen Signed-off-by: Chen Jun Signed-off-by: Zheng Zengkai --- net/bluetooth/mgmt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 12d7b368b428..13520c7b4f2f 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -7350,6 +7350,9 @@ 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; -- GitLab