misc: pci_endpoint_test: Validate BAR index in doorbell test

pci_endpoint_test_doorbell() reads the BAR number directly from an endpoint
test register and uses it as an index into test->bar[].  Add a defensive
bounds check before the dereference: positive values >= PCI_STD_NUM_BARS
are out of range, and NO_BAR (-1) as a negative signed value would slip
past an upper-bound-only check.

Signed-off-by: Carlos Bilbao (Lambda) <carlos.bilbao@kernel.org>
[mani: changed errno to -ERANGE]
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260410230300.135631-2-carlos.bilbao@kernel.org
This commit is contained in:
Carlos Bilbao 2026-04-10 16:02:59 -07:00 committed by Bjorn Helgaas
parent e4f2624395
commit 854bd081c7

View File

@ -1108,6 +1108,11 @@ static int pci_endpoint_test_doorbell(struct pci_endpoint_test *test)
pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_STATUS, 0);
bar = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_BAR);
if (bar < BAR_0 || bar >= PCI_STD_NUM_BARS) {
dev_err(dev, "BAR %d reported by endpoint out of range [0, %u]\n",
bar, PCI_STD_NUM_BARS - 1);
return -ERANGE;
}
writel(data, test->bar[bar] + addr);