diff options
author | Xu Yang <xu.yang_2@nxp.com> | 2024-12-02 16:34:53 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-04 16:11:58 +0100 |
commit | 990c2a26f703f6558042d97e7abdeb3360bb6a63 (patch) | |
tree | 1411b98b37e9061dc46f662b083f6e819454e2ed | |
parent | 04d5b4c23f3b7cbf44a71a338dae0c7aabd86c29 (diff) |
usb: chipidea: host: Improve port index sanitizing
Coverity from Synopsys complains "Illegal address computation (OVERRUN)"
on status_reg.
After below code executed,
port_index = wIndex & 0xff;
port_index -= (port_index > 0);
the static analysis tool see the value of port_index is now between 0 and
254 (inclusive).
However, ehci_def.h define port_status as below:
#define HCS_N_PORTS_MAX 15
u32 port_status[HCS_N_PORTS_MAX];
So the tool think illegal array pointer may be obtained.
status_reg = &ehci->regs->port_status[port_index];
This will follow "846cbf98cbef USB: EHCI: Improve port index sanitizing" to
improve port index sanitizing.
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20241202083453.704533-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/usb/chipidea/host.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c index 0cce19208370..442d79e32a65 100644 --- a/drivers/usb/chipidea/host.c +++ b/drivers/usb/chipidea/host.c @@ -256,8 +256,14 @@ static int ci_ehci_hub_control( struct device *dev = hcd->self.controller; struct ci_hdrc *ci = dev_get_drvdata(dev); - port_index = wIndex & 0xff; - port_index -= (port_index > 0); + /* + * Avoid out-of-bounds values while calculating the port index + * from wIndex. The compiler doesn't like pointers to invalid + * addresses, even if they are never used. + */ + port_index = (wIndex - 1) & 0xff; + if (port_index >= HCS_N_PORTS_MAX) + port_index = 0; status_reg = &ehci->regs->port_status[port_index]; spin_lock_irqsave(&ehci->lock, flags); |