From: Sean Wang sean.wang@mediatek.com

[ Upstream commit 0fab6361c4ba17d1b43a991bef4238a3c1754d35 ]

We should not access skb buffer data anymore after hci_recv_frame was called.

[ 39.634809] BUG: KASAN: use-after-free in btmtksdio_recv_event+0x1b0 [ 39.634855] Read of size 1 at addr ffffff80cf28a60d by task kworker [ 39.634962] Call trace: [ 39.634974] dump_backtrace+0x0/0x3b8 [ 39.634999] show_stack+0x20/0x2c [ 39.635016] dump_stack_lvl+0x60/0x78 [ 39.635040] print_address_description+0x70/0x2f0 [ 39.635062] kasan_report+0x154/0x194 [ 39.635079] __asan_report_load1_noabort+0x44/0x50 [ 39.635099] btmtksdio_recv_event+0x1b0/0x1c4 [ 39.635129] btmtksdio_txrx_work+0x6cc/0xac4 [ 39.635157] process_one_work+0x560/0xc5c [ 39.635177] worker_thread+0x7ec/0xcc0 [ 39.635195] kthread+0x2d0/0x3d0 [ 39.635215] ret_from_fork+0x10/0x20 [ 39.635247] Allocated by task 0: [ 39.635260] (stack is not available) [ 39.635281] Freed by task 2392: [ 39.635295] kasan_save_stack+0x38/0x68 [ 39.635319] kasan_set_track+0x28/0x3c [ 39.635338] kasan_set_free_info+0x28/0x4c [ 39.635357] ____kasan_slab_free+0x104/0x150 [ 39.635374] __kasan_slab_free+0x18/0x28 [ 39.635391] slab_free_freelist_hook+0x114/0x248 [ 39.635410] kfree+0xf8/0x2b4 [ 39.635427] skb_free_head+0x58/0x98 [ 39.635447] skb_release_data+0x2f4/0x410 [ 39.635464] skb_release_all+0x50/0x60 [ 39.635481] kfree_skb+0xc8/0x25c [ 39.635498] hci_event_packet+0x894/0xca4 [bluetooth] [ 39.635721] hci_rx_work+0x1c8/0x68c [bluetooth] [ 39.635925] process_one_work+0x560/0xc5c [ 39.635951] worker_thread+0x7ec/0xcc0 [ 39.635970] kthread+0x2d0/0x3d0 [ 39.635990] ret_from_fork+0x10/0x20 [ 39.636021] The buggy address belongs to the object at ffffff80cf28a600 which belongs to the cache kmalloc-512 of size 512 [ 39.636039] The buggy address is located 13 bytes inside of 512-byte region [ffffff80cf28a600, ffffff80cf28a800)

Fixes: 9aebfd4a2200 ("Bluetooth: mediatek: add support for MediaTek MT7663S and MT7668S SDIO devices") Co-developed-by: Yake Yang yake.yang@mediatek.com Signed-off-by: Yake Yang yake.yang@mediatek.com Signed-off-by: Sean Wang sean.wang@mediatek.com Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Anastasia Belova abelova@astralinux.ru --- Backport fix for CVE-2022-49470 drivers/bluetooth/btmtksdio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btmtksdio.c b/drivers/bluetooth/btmtksdio.c index c41560be39fb..6b31ee1a1dd9 100644 --- a/drivers/bluetooth/btmtksdio.c +++ b/drivers/bluetooth/btmtksdio.c @@ -331,6 +331,7 @@ static int btmtksdio_recv_event(struct hci_dev *hdev, struct sk_buff *skb) { struct btmtksdio_dev *bdev = hci_get_drvdata(hdev); struct hci_event_hdr *hdr = (void *)skb->data; + u8 evt = hdr->evt; int err;

/* Fix up the vendor event id with 0xff for vendor specific instead @@ -355,7 +356,7 @@ static int btmtksdio_recv_event(struct hci_dev *hdev, struct sk_buff *skb) if (err < 0) goto err_free_skb;

- if (hdr->evt == HCI_EV_VENDOR) { + if (evt == HCI_EV_VENDOR) { if (test_and_clear_bit(BTMTKSDIO_TX_WAIT_VND_EVT, &bdev->tx_state)) { /* Barrier to sync with other CPUs */