Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

USB: Remove pointless conditional in drivers/usb/serial/io_ti.c::edge_shutdown()

Coverity scan found (CID: 1708) this in
drivers/usb/serial/io_ti.c::edge_shutdown() :

...
2797 for (i=0; i < serial->num_ports; ++i) {
2798 edge_port = usb_get_serial_port_data(serial->port[i]);
2799 edge_remove_sysfs_attrs(edge_port->port);
2800 if (edge_port) {
2801 edge_buf_free(edge_port->ep_out_buf);
2802 kfree(edge_port);
2803 }
2804 usb_set_serial_port_data(serial->port[i], NULL);
2805 }
...

It's complaining that we dereference 'edge_port' in line 2799 which
makes the test of that pointer against NULL in 2800 pointless, since if
edge_port was actually NULL we'd have crashed already before reaching
line 2800.
Reading the edge_open() function it seems to me that the pointer
returned by usb_get_serial_port_data(serial->port[i]) and stored in
'edge_port' can never actually be NULL here, so the test is entirely
superfluous (even if it could be NULL it would be pointless here,
ignoring the then possible crash in that case, since both
edge_buf_free() and kfree() can handle being passed NULL pointers.

This patch removes the pointless conditional (and also makes a few
tiny style corrections now that I was in the area anyway).


Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

authored by

Jesper Juhl and committed by
Greg Kroah-Hartman
0d46c007 167a675a

+4 -6
+4 -6
drivers/usb/serial/io_ti.c
··· 2794 2794 2795 2795 dbg ("%s", __FUNCTION__); 2796 2796 2797 - for (i=0; i < serial->num_ports; ++i) { 2797 + for (i = 0; i < serial->num_ports; ++i) { 2798 2798 edge_port = usb_get_serial_port_data(serial->port[i]); 2799 2799 edge_remove_sysfs_attrs(edge_port->port); 2800 - if (edge_port) { 2801 - edge_buf_free(edge_port->ep_out_buf); 2802 - kfree(edge_port); 2803 - } 2800 + edge_buf_free(edge_port->ep_out_buf); 2801 + kfree(edge_port); 2804 2802 usb_set_serial_port_data(serial->port[i], NULL); 2805 2803 } 2806 - kfree (usb_get_serial_data(serial)); 2804 + kfree(usb_get_serial_data(serial)); 2807 2805 usb_set_serial_data(serial, NULL); 2808 2806 } 2809 2807