diff options
| author | Zekun Shen <bruceshenzk@gmail.com> | 2020-06-23 18:11:05 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-29 09:07:20 +0100 |
| commit | 73ff79e48013e11ca778758be31944f9159f555e (patch) | |
| tree | 235423a9f2f992c3fbc8f6338dc57ba5bfbe83d7 | |
| parent | 73eae769d588d97ce5f2e8b88fcfbf1052ae77e5 (diff) | |
ath10k: check idx validity in __ath10k_htt_rx_ring_fill_n()
[ Upstream commit bad60b8d1a7194df38fd7fe4b22f3f4dcf775099 ]
The idx in __ath10k_htt_rx_ring_fill_n function lives in
consistent dma region writable by the device. Malfunctional
or malicious device could manipulate such idx to have a OOB
write. Either by
htt->rx_ring.netbufs_ring[idx] = skb;
or by
ath10k_htt_set_paddrs_ring(htt, paddr, idx);
The idx can also be negative as it's signed, giving a large
memory space to write to.
It's possibly exploitable by corruptting a legit pointer with
a skb pointer. And then fill skb with payload as rougue object.
Part of the log here. Sometimes it appears as UAF when writing
to a freed memory by chance.
[ 15.594376] BUG: unable to handle page fault for address: ffff887f5c1804f0
[ 15.595483] #PF: supervisor write access in kernel mode
[ 15.596250] #PF: error_code(0x0002) - not-present page
[ 15.597013] PGD 0 P4D 0
[ 15.597395] Oops: 0002 [#1] SMP KASAN PTI
[ 15.597967] CPU: 0 PID: 82 Comm: kworker/u2:2 Not tainted 5.6.0 #69
[ 15.598843] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[ 15.600438] Workqueue: ath10k_wq ath10k_core_register_work [ath10k_core]
[ 15.601389] RIP: 0010:__ath10k_htt_rx_ring_fill_n
(linux/drivers/net/wireless/ath/ath10k/htt_rx.c:173) ath10k_core
Signed-off-by: Zekun Shen <bruceshenzk@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200623221105.3486-1-bruceshenzk@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/net/wireless/ath/ath10k/htt_rx.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c index 21642bab485a..fd276e54bb7c 100644 --- a/drivers/net/wireless/ath/ath10k/htt_rx.c +++ b/drivers/net/wireless/ath/ath10k/htt_rx.c @@ -100,6 +100,14 @@ static int __ath10k_htt_rx_ring_fill_n(struct ath10k_htt *htt, int num) BUILD_BUG_ON(HTT_RX_RING_FILL_LEVEL >= HTT_RX_RING_SIZE / 2); idx = __le32_to_cpu(*htt->rx_ring.alloc_idx.vaddr); + + if (idx < 0 || idx >= htt->rx_ring.size) { + ath10k_err(htt->ar, "rx ring index is not valid, firmware malfunctioning?\n"); + idx &= htt->rx_ring.size_mask; + ret = -ENOMEM; + goto fail; + } + while (num > 0) { skb = dev_alloc_skb(HTT_RX_BUF_SIZE + HTT_RX_DESC_ALIGN); if (!skb) { |