| Message ID | 20190904160339.2800-1-niklas.cassel@linaro.org (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Commit | d76d273dc861416ac435781818b3a7468bd47d9d |
| Headers | show |
| Series | PCI: dwc: fix find_next_bit() usage | expand |
On Wed, Sep 4, 2019 at 17:3:38, Niklas Cassel <niklas.cassel@linaro.org> wrote: > 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()") > Signed-off-by: Niklas Cassel <niklas.cassel@linaro.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 d3156446ff27..45f21640c977 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) + > -- > 2.21.0 Hi Niklas! The patch looks nice! Thanks! Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
On Wed, Sep 04, 2019 at 06:03:38PM +0200, Niklas Cassel wrote: > 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()") > Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org> > --- Reviewed-by: Andrew Murray <andrew.murray@arm.com> > 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 d3156446ff27..45f21640c977 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) + > -- > 2.21.0 >
On Wed, Sep 4, 2019 at 9:03 AM Niklas Cassel <niklas.cassel@linaro.org> wrote: > > 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()") > Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org> Tested-by: Bjorn Andersson <bjorn.andersson@linaro.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 d3156446ff27..45f21640c977 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) + > -- > 2.21.0 >
On Wed, Sep 04, 2019 at 06:03:38PM +0200, Niklas Cassel wrote: > 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()") > Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org> > --- > drivers/pci/controller/dwc/pcie-designware-host.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) Applied to pci/dwc, thanks. Lorenzo > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index d3156446ff27..45f21640c977 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) + > -- > 2.21.0 >
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index d3156446ff27..45f21640c977 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) +
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()") Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org> --- drivers/pci/controller/dwc/pcie-designware-host.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)