Hello Mathias Nyman,
The patch c99b38c41234: "xhci: add support to allocate several
interrupters" from Jan 2, 2024 (linux-next), leads to the following
Smatch static checker warning:
drivers/usb/host/xhci-mem.c:1873 xhci_remove_secondary_interrupter()
error: we previously assumed 'ir' could be null (see line 1865)
drivers/usb/host/xhci-mem.c
1863
1864 /* interrupter 0 is primary interrupter, don't touch it */
1865 if (!ir || !ir->intr_num || ir->intr_num >= xhci->max_interrupters)
1866 xhci_dbg(xhci, "Invalid secondary interrupter, can't remove\n");
This debug message is kind of pointless... The Oops will have the stack
trace already.
1867
1868 /* fixme, should we check xhci->interrupter[intr_num] == ir */
1869 /* fixme locking */
1870
1871 spin_lock_irq(&xhci->lock);
1872
--> 1873 intr_num = ir->intr_num;
^^^^^^^^^^^^
Unchecked dereference
1874
1875 xhci_remove_interrupter(xhci, ir);
1876 xhci->interrupters[intr_num] = NULL;
1877
1878 spin_unlock_irq(&xhci->lock);
1879
1880 xhci_free_interrupter(xhci, ir);
1881 }
regards,
dan carpenter
