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authorStephan Gerhold <stephan@gerhold.net>2019-11-10 17:19:15 +0100
committerDavid S. Miller <davem@davemloft.net>2019-11-11 21:40:55 -0800
commita71a29f50de1ef97ab55c151a1598eb12dde379d (patch)
treed695d3ecd23feec8c098e56b35497a11e54ab109 /drivers/nfc
parent73a533ecf0af5f73ff72dd7c96d1c8598ca93649 (diff)
downloadlinux-a71a29f50de1ef97ab55c151a1598eb12dde379d.tar.bz2
NFC: nxp-nci: Fix NULL pointer dereference after I2C communication error
I2C communication errors (-EREMOTEIO) during the IRQ handler of nxp-nci result in a NULL pointer dereference at the moment: BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: 0002 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 355 Comm: irq/137-nxp-nci Not tainted 5.4.0-rc6 #1 RIP: 0010:skb_queue_tail+0x25/0x50 Call Trace: nci_recv_frame+0x36/0x90 [nci] nxp_nci_i2c_irq_thread_fn+0xd1/0x285 [nxp_nci_i2c] ? preempt_count_add+0x68/0xa0 ? irq_forced_thread_fn+0x80/0x80 irq_thread_fn+0x20/0x60 irq_thread+0xee/0x180 ? wake_threads_waitq+0x30/0x30 kthread+0xfb/0x130 ? irq_thread_check_affinity+0xd0/0xd0 ? kthread_park+0x90/0x90 ret_from_fork+0x1f/0x40 Afterward the kernel must be rebooted to work properly again. This happens because it attempts to call nci_recv_frame() with skb == NULL. However, unlike nxp_nci_fw_recv_frame(), nci_recv_frame() does not have any NULL checks for skb, causing the NULL pointer dereference. Change the code to call only nxp_nci_fw_recv_frame() in case of an error. Make sure to log it so it is obvious that a communication error occurred. The error above then becomes: nxp-nci_i2c i2c-NXP1001:00: NFC: Read failed with error -121 nci: __nci_request: wait_for_completion_interruptible_timeout failed 0 nxp-nci_i2c i2c-NXP1001:00: NFC: Read failed with error -121 Fixes: 6be88670fc59 ("NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver") Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/nfc')
-rw-r--r--drivers/nfc/nxp-nci/i2c.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/nfc/nxp-nci/i2c.c b/drivers/nfc/nxp-nci/i2c.c
index 307bd2afbe05..4d1909aecd6c 100644
--- a/drivers/nfc/nxp-nci/i2c.c
+++ b/drivers/nfc/nxp-nci/i2c.c
@@ -220,8 +220,10 @@ static irqreturn_t nxp_nci_i2c_irq_thread_fn(int irq, void *phy_id)
if (r == -EREMOTEIO) {
phy->hard_fault = r;
- skb = NULL;
- } else if (r < 0) {
+ if (info->mode == NXP_NCI_MODE_FW)
+ nxp_nci_fw_recv_frame(phy->ndev, NULL);
+ }
+ if (r < 0) {
nfc_err(&client->dev, "Read failed with error %d\n", r);
goto exit_irq_handled;
}