f1e941dbf8
When the pn532 uart device is detaching, the pn532_uart_remove()
is called. But there are no functions in pn532_uart_remove() that
could delete the cmd_timeout timer, which will cause use-after-free
bugs. The process is shown below:
(thread 1) | (thread 2)
| pn532_uart_send_frame
pn532_uart_remove | mod_timer(&pn532->cmd_timeout,...)
... | (wait a time)
kfree(pn532) //FREE | pn532_cmd_timeout
| pn532_uart_send_frame
| pn532->... //USE
This patch adds del_timer_sync() in pn532_uart_remove() in order to
prevent the use-after-free bugs. What's more, the pn53x_unregister_nfc()
is well synchronized, it sets nfc_dev->shutting_down to true and there
are no syscalls could restart the cmd_timeout timer.
Fixes:
|
||
|---|---|---|
| .. | ||
| fdp | ||
| microread | ||
| nfcmrvl | ||
| nxp-nci | ||
| pn533 | ||
| pn544 | ||
| s3fwrn5 | ||
| st-nci | ||
| st21nfca | ||
| st95hf | ||
| Kconfig | ||
| Makefile | ||
| mei_phy.c | ||
| mei_phy.h | ||
| nfcsim.c | ||
| port100.c | ||
| trf7970a.c | ||
| virtual_ncidev.c | ||