| Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
nfc: st-nci: Fix use after free bug in ndlc_remove due to race condition
This bug influences both st_nci_i2c_remove and st_nci_spi_remove.
Take st_nci_i2c_remove as an example.
In st_nci_i2c_probe, it called ndlc_probe and bound &ndlc->sm_work
with llt_ndlc_sm_work.
When it calls ndlc_recv or timeout handler, it will finally call
schedule_work to start the work.
When we call st_nci_i2c_remove to remove the driver, there
may be a sequence as follows:
Fix it by finishing the work before cleanup in ndlc_remove
CPU0 CPU1
|llt_ndlc_sm_work
st_nci_i2c_remove |
ndlc_remove |
st_nci_remove |
nci_free_device|
kfree(ndev) |
//free ndlc->ndev |
|llt_ndlc_rcv_queue
|nci_recv_frame
|//use ndlc->ndev |
