diff options
| author | Randy Dunlap <rdunlap@infradead.org> | 2019-09-16 16:12:23 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-10-17 13:42:37 -0700 |
| commit | 091c0f11f2722c251ed6f623ea01371c498eca11 (patch) | |
| tree | d22fb091611b6d7e91ead66edd0350d99cf01636 | |
| parent | f56ae521d30e0a4cb97dfb8da27a115814eed71d (diff) | |
serial: uartlite: fix exit path null pointer
commit a553add0846f355a28ed4e81134012e4a1e280c2 upstream.
Call uart_unregister_driver() conditionally instead of
unconditionally, only if it has been previously registered.
This uses driver.state, just as the sh-sci.c driver does.
Fixes this null pointer dereference in tty_unregister_driver(),
since the 'driver' argument is null:
general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:tty_unregister_driver+0x25/0x1d0
Fixes: 238b8721a554 ("[PATCH] serial uartlite driver")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: stable <stable@vger.kernel.org>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Link: https://lore.kernel.org/r/9c8e6581-6fcc-a595-0897-4d90f5d710df@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/uartlite.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c index 817bb0d3f326..9a54aafe8405 100644 --- a/drivers/tty/serial/uartlite.c +++ b/drivers/tty/serial/uartlite.c @@ -746,7 +746,8 @@ err_uart: static void __exit ulite_exit(void) { platform_driver_unregister(&ulite_platform_driver); - uart_unregister_driver(&ulite_uart_driver); + if (ulite_uart_driver.state) + uart_unregister_driver(&ulite_uart_driver); } module_init(ulite_init); |