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| author | Duoming Zhou <duoming@zju.edu.cn> | 2022-05-17 09:25:30 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-05-25 09:14:36 +0200 |
| commit | 3277789f332ed34d46d35ee84992fd643f48aa4a (patch) | |
| tree | d8c85c8e294be21a53a561c013f4e0b5c6552e31 /net/nfc | |
| parent | b368e07fb44dd4a6dab2b89f7cdbf61931536bf4 (diff) | |
| download | linux-stable-3277789f332ed34d46d35ee84992fd643f48aa4a.tar.gz linux-stable-3277789f332ed34d46d35ee84992fd643f48aa4a.tar.bz2 linux-stable-3277789f332ed34d46d35ee84992fd643f48aa4a.zip | |
NFC: nci: fix sleep in atomic context bugs caused by nci_skb_alloc
[ Upstream commit 23dd4581350d4ffa23d58976ec46408f8f4c1e16 ]
There are sleep in atomic context bugs when the request to secure
element of st-nci is timeout. The root cause is that nci_skb_alloc
with GFP_KERNEL parameter is called in st_nci_se_wt_timeout which is
a timer handler. The call paths that could trigger bugs are shown below:
(interrupt context 1)
st_nci_se_wt_timeout
nci_hci_send_event
nci_hci_send_data
nci_skb_alloc(..., GFP_KERNEL) //may sleep
(interrupt context 2)
st_nci_se_wt_timeout
nci_hci_send_event
nci_hci_send_data
nci_send_data
nci_queue_tx_data_frags
nci_skb_alloc(..., GFP_KERNEL) //may sleep
This patch changes allocation mode of nci_skb_alloc from GFP_KERNEL to
GFP_ATOMIC in order to prevent atomic context sleeping. The GFP_ATOMIC
flag makes memory allocation operation could be used in atomic context.
Fixes: ed06aeefdac3 ("nfc: st-nci: Rename st21nfcb to st-nci")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220517012530.75714-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/nfc')
| -rw-r--r-- | net/nfc/nci/data.c | 2 | ||||
| -rw-r--r-- | net/nfc/nci/hci.c | 4 |
2 files changed, 3 insertions, 3 deletions
diff --git a/net/nfc/nci/data.c b/net/nfc/nci/data.c index ce3382be937f..b002e18f38c8 100644 --- a/net/nfc/nci/data.c +++ b/net/nfc/nci/data.c @@ -118,7 +118,7 @@ static int nci_queue_tx_data_frags(struct nci_dev *ndev, skb_frag = nci_skb_alloc(ndev, (NCI_DATA_HDR_SIZE + frag_len), - GFP_KERNEL); + GFP_ATOMIC); if (skb_frag == NULL) { rc = -ENOMEM; goto free_exit; diff --git a/net/nfc/nci/hci.c b/net/nfc/nci/hci.c index 04e55ccb3383..4fe336ff2bfa 100644 --- a/net/nfc/nci/hci.c +++ b/net/nfc/nci/hci.c @@ -153,7 +153,7 @@ static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe, i = 0; skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len + - NCI_DATA_HDR_SIZE, GFP_KERNEL); + NCI_DATA_HDR_SIZE, GFP_ATOMIC); if (!skb) return -ENOMEM; @@ -186,7 +186,7 @@ static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe, if (i < data_len) { skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len + - NCI_DATA_HDR_SIZE, GFP_KERNEL); + NCI_DATA_HDR_SIZE, GFP_ATOMIC); if (!skb) return -ENOMEM; |