diff mbox series

[2/4] xhci: fix off by one check when adding a secondary interrupter.

Message ID 20240125152737.2983959-3-mathias.nyman@linux.intel.com
State New
Headers show
Series xhci fixes for usb-linus | expand

Commit Message

Mathias Nyman Jan. 25, 2024, 3:27 p.m. UTC
The sanity check of interrupter index when adding a new interrupter is
off by one. intr_num needs to be smaller than xhci->max_interrupter to
fit the array of interrupters.

Luckily this doesn't cause any real word harm as xhci_add_interrupter()
is always called with a intr_num value smaller than xhci->max_interrupters
in any current kernel.

Should not be needed for stable as 6.7 kernel and older only supports
one interrupter, with intr_num always being zero.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-usb/e9771296-586d-456a-ac24-a82de79bb2e6@moroto.mountain/
Fixes: 4bf398e15aa4 ("xhci: split allocate interrupter into separate alloacte and add parts")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
 drivers/usb/host/xhci-mem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index d00d4d937236..a7716202a8dd 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2322,7 +2322,7 @@  xhci_add_interrupter(struct xhci_hcd *xhci, struct xhci_interrupter *ir,
 	u64 erst_base;
 	u32 erst_size;
 
-	if (intr_num > xhci->max_interrupters) {
+	if (intr_num >= xhci->max_interrupters) {
 		xhci_warn(xhci, "Can't add interrupter %d, max interrupters %d\n",
 			  intr_num, xhci->max_interrupters);
 		return -EINVAL;