From: Niklas Cassel niklas.cassel@linaro.org
[ Upstream commit 1137e61dcb99f7f8b54e77ed83f68b5b485a3e34 ]
find_next_bit() takes a parameter of size long, and performs arithmetic that assumes that the argument is of size long.
Therefore we cannot pass a u32, since this will cause find_next_bit() to read outside the stack buffer and will produce the following print: BUG: KASAN: stack-out-of-bounds in find_next_bit+0x38/0xb0
Fixes: 1b497e6493c4 ("PCI: dwc: Fix uninitialized variable in dw_handle_msi_irq()") Tested-by: Bjorn Andersson bjorn.andersson@linaro.org Signed-off-by: Niklas Cassel niklas.cassel@linaro.org Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Reviewed-by: Andrew Murray andrew.murray@arm.com Acked-by: Gustavo Pimentel gustavo.pimentel@synopsys.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/controller/dwc/pcie-designware-host.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 0f36a926059a..8615f1548882 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -78,7 +78,8 @@ static struct msi_domain_info dw_pcie_msi_domain_info = { irqreturn_t dw_handle_msi_irq(struct pcie_port *pp) { int i, pos, irq; - u32 val, num_ctrls; + unsigned long val; + u32 status, num_ctrls; irqreturn_t ret = IRQ_NONE;
num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL; @@ -86,14 +87,14 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp) for (i = 0; i < num_ctrls; i++) { dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_STATUS + (i * MSI_REG_CTRL_BLOCK_SIZE), - 4, &val); - if (!val) + 4, &status); + if (!status) continue;
ret = IRQ_HANDLED; + val = status; pos = 0; - while ((pos = find_next_bit((unsigned long *) &val, - MAX_MSI_IRQS_PER_CTRL, + while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL, pos)) != MAX_MSI_IRQS_PER_CTRL) { irq = irq_find_mapping(pp->irq_domain, (i * MAX_MSI_IRQS_PER_CTRL) +