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| author | Zekun Shen <bruceshenzk@gmail.com> | 2020-06-23 18:11:05 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-30 10:38:32 +0100 |
| commit | f34426b44d24f4624e49dc122526f603afc85973 (patch) | |
| tree | 0e846f901b118a71d13c035913b6834b2acee1c1 | |
| parent | 30255785272f896d1f275f095eb0b2089426b153 (diff) | |
| download | linux-stable-f34426b44d24f4624e49dc122526f603afc85973.tar.gz linux-stable-f34426b44d24f4624e49dc122526f603afc85973.tar.bz2 linux-stable-f34426b44d24f4624e49dc122526f603afc85973.zip | |
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 03d4cc6f35bc..7d15f6208b46 100644 --- a/drivers/net/wireless/ath/ath10k/htt_rx.c +++ b/drivers/net/wireless/ath/ath10k/htt_rx.c @@ -153,6 +153,14 @@ 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) { |