From dcdb52d948f3a17ccd3fce757d9bd981d7c32039 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 9 Aug 2024 15:44:07 +0300 Subject: usb: xhci: Check for xhci->interrupters being allocated in xhci_mem_clearup() If xhci_mem_init() fails, it calls into xhci_mem_cleanup() to mop up the damage. If it fails early enough, before xhci->interrupters is allocated but after xhci->max_interrupters has been set, which happens in most (all?) cases, things get uglier, as xhci_mem_cleanup() unconditionally derefences xhci->interrupters. With prejudice. Gate the interrupt freeing loop with a check on xhci->interrupters being non-NULL. Found while debugging a DMA allocation issue that led the XHCI driver on this exact path. Fixes: c99b38c41234 ("xhci: add support to allocate several interrupters") Cc: Mathias Nyman Cc: Wesley Cheng Cc: Greg Kroah-Hartman Signed-off-by: Marc Zyngier Cc: stable@vger.kernel.org # 6.8+ Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20240809124408.505786-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-mem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/usb') diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index d7654f475daf..937ce5fd5809 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -1872,7 +1872,7 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci) cancel_delayed_work_sync(&xhci->cmd_timer); - for (i = 0; i < xhci->max_interrupters; i++) { + for (i = 0; xhci->interrupters && i < xhci->max_interrupters; i++) { if (xhci->interrupters[i]) { xhci_remove_interrupter(xhci, xhci->interrupters[i]); xhci_free_interrupter(xhci, xhci->interrupters[i]); -- cgit v1.2.3