A compromized ath10k peripheral is able to control the size argument
of memcpy in ath10k_pci_hif_exchange_bmi_msg.
The min result from previous line is not used as the size argument
for memcpy. Instead, xfer.resp_len comes from untrusted stream dma
input. The value comes from "nbytes" in ath10k_pci_bmi_recv_data,
which is set inside _ath10k_ce_completed_recv_next_nolock with the line
nbytes = __le16_to_cpu(sdesc.nbytes);
sdesc is a stream dma region which device can write to.
Signed-off-by: Zekun Shen <bruceshe...@gmail.com>
---
KASAN report stacktrace:
[ 6.293972]
==================================================================
[ 6.295696] BUG: KASAN: slab-out-of-bounds in
ath10k_pci_hif_exchange_bmi_msg+0xb2f/0x14d0 [ath10k_pci]
[ 6.297031] Read of size 9769 at addr ffff888034c49c00 by task
kworker/u2:2/82
[ 6.298054]
[ 6.298288] CPU: 0 PID: 82 Comm: kworker/u2:2 Tainted: G W
5.6.0 #51
[ 6.299410] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/4
[ 6.301107] Workqueue: ath10k_wq ath10k_core_register_work [ath10k_core]
[ 6.302203] Call Trace:
[ 6.302596] dump_stack+0x75/0x9b
[ 6.303114] ? ath10k_pci_hif_exchange_bmi_msg+0xb2f/0x14d0 [ath10k_pci]
[ 6.304096] print_address_description.constprop.5+0x16/0x310
[ 6.304933] ? ath10k_pci_hif_exchange_bmi_msg+0xb2f/0x14d0 [ath10k_pci]
[ 6.305898] ? ath10k_pci_hif_exchange_bmi_msg+0xb2f/0x14d0 [ath10k_pci]
[ 6.306873] __kasan_report+0x158/0x1c0
[ 6.307441] ? ath10k_pci_hif_exchange_bmi_msg+0xb2f/0x14d0 [ath10k_pci]
[ 6.308432] kasan_report+0xe/0x20
[ 6.308938] check_memory_region+0x15d/0x1b0
[ 6.309564] memcpy+0x1f/0x50
[ 6.310006] ath10k_pci_hif_exchange_bmi_msg+0xb2f/0x14d0 [ath10k_pci]
[ 6.310947] ? ath10k_pci_rx_replenish_retry+0x170/0x170 [ath10k_pci]
[ 6.311875] ? check_unmap+0x64e/0x1bb0
[ 6.312439] ? _raw_write_lock+0xd0/0xd0
[ 6.313045] ? log_store.constprop.29+0x267/0x440
[ 6.313732] ? debug_dma_free_coherent+0x1c0/0x220
[ 6.314440] ? debug_dma_alloc_coherent+0x2f0/0x2f0
[ 6.315156] ath10k_bmi_get_target_info+0x1b8/0x350 [ath10k_core]
[ 6.316058] ? apic_timer_interrupt+0xa/0x20
[ 6.316710] ? ath10k_bmi_done+0x330/0x330 [ath10k_core]
[ 6.317509] ? ath10k_pci_diag_write_mem+0x31e/0x570 [ath10k_pci]
[ 6.318402] ? __kasan_check_read+0x10/0x10
[ 6.319037] ? _raw_spin_lock_irqsave+0x7b/0xd0
[ 6.319755] ? _raw_write_lock_irqsave+0xd0/0xd0
[ 6.320463] ? lock_timer_base+0xbc/0x150
[ 6.321047] ? enqueue_timer+0xda/0x270
[ 6.321612] ? mod_timer+0x406/0xad0
[ 6.322147] ? timer_reduce+0xb00/0xb00
[ 6.322707] ? _raw_write_lock_irqsave+0xd0/0xd0
[ 6.323380] ? ath10k_pci_sleep.part.14+0x163/0x1c0 [ath10k_pci]
[ 6.324248] ? ath10k_bus_pci_write32+0x158/0x1b0 [ath10k_pci]
[ 6.325099] ? ath10k_pci_hif_power_up+0x256/0x690 [ath10k_pci]
[ 6.325970] ? __switch_to_asm+0x40/0x70
[ 6.326565] ath10k_core_register_work+0x799/0x2070 [ath10k_core]
[ 6.327453] ? __switch_to_asm+0x34/0x70
[ 6.328028] ? __switch_to_asm+0x40/0x70
[ 6.328603] ? __switch_to+0x5d5/0xde0
[ 6.329144] ? __switch_to_asm+0x34/0x70
[ 6.329754] ? ath10k_core_stop+0xf0/0xf0 [ath10k_core]
[ 6.330521] ? __schedule+0x88c/0x1820
[ 6.331068] ? read_word_at_a_time+0xe/0x20
[ 6.331675] ? strscpy+0xa3/0x320
[ 6.332162] process_one_work+0x83c/0x14c0
[ 6.332777] worker_thread+0x82/0xee0
[ 6.333335] ? __kthread_parkme+0x8a/0x100
[ 6.333955] ? process_one_work+0x14c0/0x14c0
[ 6.334592] kthread+0x2f1/0x3a0
[ 6.335070] ? kthread_create_on_node+0xc0/0xc0
[ 6.335785] ret_from_fork+0x35/0x40
[ 6.367721]
==================================================================
drivers/net/wireless/ath/ath10k/pci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath10k/pci.c
b/drivers/net/wireless/ath/ath10k/pci.c
index 1d941d53f..ad28d9156 100644
--- a/drivers/net/wireless/ath/ath10k/pci.c
+++ b/drivers/net/wireless/ath/ath10k/pci.c
@@ -2184,7 +2184,7 @@ int ath10k_pci_hif_exchange_bmi_msg(struct ath10k *ar,
if (ret == 0 && resp_len) {
*resp_len = min(*resp_len, xfer.resp_len);
- memcpy(resp, tresp, xfer.resp_len);
+ memcpy(resp, tresp, *resp_len);
}
err_dma:
kfree(treq);
--
2.17.1
