diff options
| author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2018-12-26 22:09:34 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-12 20:02:30 +0100 |
| commit | 25cb6653e588cea0e09927bec7f14796b1373ef5 (patch) | |
| tree | a6c78f2a395caf9f7f562c42c5a84dd1ee69af3c /drivers/isdn | |
| parent | 6ffef4ce8b88b3401195510366803bb493aa0bbe (diff) | |
isdn: hisax: hfc_pci: Fix a possible concurrency use-after-free bug in HFCPCI_l1hw()
[ Upstream commit 7418e6520f22a2e35815122fa5a53d5bbfa2c10f ]
In drivers/isdn/hisax/hfc_pci.c, the functions hfcpci_interrupt() and
HFCPCI_l1hw() may be concurrently executed.
HFCPCI_l1hw()
line 1173: if (!cs->tx_skb)
hfcpci_interrupt()
line 942: spin_lock_irqsave();
line 1066: dev_kfree_skb_irq(cs->tx_skb);
Thus, a possible concurrency use-after-free bug may occur
in HFCPCI_l1hw().
To fix these bugs, the calls to spin_lock_irqsave() and
spin_unlock_irqrestore() are added in HFCPCI_l1hw(), to protect the
access to cs->tx_skb.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/isdn')
| -rw-r--r-- | drivers/isdn/hisax/hfc_pci.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/isdn/hisax/hfc_pci.c b/drivers/isdn/hisax/hfc_pci.c index ea0e4c6de3fb..0109e0e8bcb6 100644 --- a/drivers/isdn/hisax/hfc_pci.c +++ b/drivers/isdn/hisax/hfc_pci.c @@ -1170,11 +1170,13 @@ HFCPCI_l1hw(struct PStack *st, int pr, void *arg) if (cs->debug & L1_DEB_LAPD) debugl1(cs, "-> PH_REQUEST_PULL"); #endif + spin_lock_irqsave(&cs->lock, flags); if (!cs->tx_skb) { test_and_clear_bit(FLG_L1_PULL_REQ, &st->l1.Flags); st->l1.l1l2(st, PH_PULL | CONFIRM, NULL); } else test_and_set_bit(FLG_L1_PULL_REQ, &st->l1.Flags); + spin_unlock_irqrestore(&cs->lock, flags); break; case (HW_RESET | REQUEST): spin_lock_irqsave(&cs->lock, flags); |