Fix pointer dereference before call to pcie_bus_configure_settings
A message that is not in the archive (sent off-list or not yet received): [email protected]
Jon Mason,
I just noticed that you had just an "Acked-by:" on this one. It
really should be a "Signed-off-by:" since it's passing through you. Can I get that?
Also, the commit message is a bit unclear. "introduces a few issues"? Can you guys elaborate on details? Oopses? Not being able to find devices? What?
Linus
Quoted 68 lines · Jon Mason
From: Shyam Iyer <[email protected]>
Commit
b03e7495a862b028294f59fc87286d6d78ee7fa1introduces a few issues by dereferencingbus->selfin the call topcie_bus_configure_settings.This fixes it by checking existence of
bus->selfbefore dereferencing it.Reported-by Stanislaw Gruszka <[email protected]>Signed-off-by Shyam Iyer <[email protected]>Acked-by Jon Mason <[email protected]>---
arch/x86/pci/acpi.c | 9 +++++++--drivers/pci/hotplug/pcihp_slot.c| 4 +++-drivers/pci/probe.c| 3 ---3 files changed, 10 insertions(+), 6 deletions(-)arch/x86/pci/acpi.c +7
-2@@ -365,8 +365,13 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)*/ if (bus) { struct pci_bus *child; - list_for_each_entry(child, &bus->children, node) - pcie_bus_configure_settings(child, child->self->pcie_mpss); + list_for_each_entry(child, &bus->children, node) { + struct pci_dev *self = child->self; + if (!self) + continue; + + pcie_bus_configure_settings(child, self->pcie_mpss); + } } if (!bus)drivers/pci/hotplug/pcihp_slot.c +3
-1@@ -169,7 +169,9 @@ void pci_configure_slot(struct pci_dev *dev) (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI))) return; - pcie_bus_configure_settings(dev->bus, dev->bus->self->pcie_mpss); + if (dev->bus && dev->bus->self) + pcie_bus_configure_settings(dev->bus, + dev->bus->self->pcie_mpss); memset(&hpp, 0, sizeof(hpp)); ret = pci_get_hp_params(dev, &hpp);drivers/pci/probe.c +0
-4@@ -1456,9 +1456,6 @@ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss) { u8 smpss = mpss; - if (!bus->self) - return; - if (!pci_is_pcie(bus->self)) return; --1.7.6
PATCH 1/2 Fix pointer dereference before call to pcie_bus_configure_settings
There is a potential NULL pointer dereference in calls to pcie_bus_configure_settings due to attempts to access pci_bus self variables when the self pointer is NULL. To correct this, verify that the self pointer in pci_bus is non-NULL before dereferencing it.
arch/x86/pci/acpi.c +7 -2
@@ -365,8 +365,13 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)*/ if (bus) {struct pci_bus *child; -list_for_each_entry (child, &bus->children, node) -pcie_bus_configure_settings (child, child->self->pcie_mpss); +list_for_each_entry (child, &bus->children, node) { +struct pci_dev *self = child->self; +if (!self) +continue ; + +pcie_bus_configure_settings (child, self->pcie_mpss); + } }if (!bus)
drivers/pci/hotplug/pcihp_slot.c +3 -1
@@ -169,7 +169,9 @@ void pci_configure_slot(struct pci_dev *dev) (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))return ; -pcie_bus_configure_settings (dev->bus, dev->bus->self->pcie_mpss); +if (dev->bus && dev->bus->self) +pcie_bus_configure_settings (dev->bus, + dev->bus->self->pcie_mpss);memset (&hpp,0 ,sizeof (hpp)); ret =pci_get_hp_params (dev, &hpp);
drivers/pci/probe.c +0 -3
@@ -1456,9 +1456,6 @@ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss) {u8 smpss = mpss; -if (!bus->self) -return ; -if (!pci_is_pcie (bus->self))return ;
Quoted 5 lines · Jon Mason
There is a potential NULL pointer dereference in calls to
pcie_bus_configure_settingsdue to attempts to accesspci_busself variables when the self pointer is NULL. To correct this, verify that the self pointer inpci_busis non-NULL before dereferencing it.
Thanks,
Linus