6.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
commit 0cca961a026177af69044f10d6ae76d8ce043764 upstream.
The pci_bus_release_domain_nr() API is supposed to free the domain
number allocated by pci_bus_find_domain_nr(). Most of the callers of
pci_bus_find_domain_nr(), store the domain number in pci_bus::domain_nr.
As such, the pci_bus_release_domain_nr() implicitly frees the domain
number by dereferencing 'struct pci_bus'. However, one of the callers
of this API, the PCI endpoint subsystem, doesn't have 'struct pci_bus',
so it only passes NULL. Due to this, the API will end up dereferencing
the NULL pointer.
To fix this issue, pass the domain number to this API explicitly. Since
'struct pci_bus' is not used for anything else other than extracting the
domain number, it makes sense to pass the domain number directly.
Fixes: 0328947c5032 ("PCI: endpoint: Assign PCI domain number for endpoint controllers")
Closes: https://lore.kernel.org/linux-pci/c0c40ddb-bf64-4b22-9dd1-8dbb18aa2813@stanley.mountain
Link: https://lore.kernel.org/linux-pci/20240912053025.25314-1-manivannan.sadhasivam@xxxxxxxxxx
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/pci/endpoint/pci-epc-core.c | 2 +-
drivers/pci/pci.c | 14 +++++++-------
drivers/pci/probe.c | 2 +-
drivers/pci/remove.c | 2 +-
include/linux/pci.h | 2 +-
5 files changed, 11 insertions(+), 11 deletions(-)
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -840,7 +840,7 @@ void pci_epc_destroy(struct pci_epc *epc
device_unregister(&epc->dev);
#ifdef CONFIG_PCI_DOMAINS_GENERIC
- pci_bus_release_domain_nr(NULL, &epc->dev);
+ pci_bus_release_domain_nr(&epc->dev, epc->domain_nr);
#endif
}
EXPORT_SYMBOL_GPL(pci_epc_destroy);
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -6814,16 +6814,16 @@ static int of_pci_bus_find_domain_nr(str
return ida_alloc(&pci_domain_nr_dynamic_ida, GFP_KERNEL);
}
-static void of_pci_bus_release_domain_nr(struct pci_bus *bus, struct device *parent)
+static void of_pci_bus_release_domain_nr(struct device *parent, int domain_nr)
{
- if (bus->domain_nr < 0)
+ if (domain_nr < 0)
return;
/* Release domain from IDA where it was allocated. */
- if (of_get_pci_domain_nr(parent->of_node) == bus->domain_nr)
- ida_free(&pci_domain_nr_static_ida, bus->domain_nr);
+ if (of_get_pci_domain_nr(parent->of_node) == domain_nr)
+ ida_free(&pci_domain_nr_static_ida, domain_nr);
else
- ida_free(&pci_domain_nr_dynamic_ida, bus->domain_nr);
+ ida_free(&pci_domain_nr_dynamic_ida, domain_nr);
}
int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
@@ -6832,11 +6832,11 @@ int pci_bus_find_domain_nr(struct pci_bu
acpi_pci_bus_find_domain_nr(bus);
}
-void pci_bus_release_domain_nr(struct pci_bus *bus, struct device *parent)
+void pci_bus_release_domain_nr(struct device *parent, int domain_nr)
{
if (!acpi_disabled)
return;
- of_pci_bus_release_domain_nr(bus, parent);
+ of_pci_bus_release_domain_nr(parent, domain_nr);
}
#endif
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1061,7 +1061,7 @@ unregister:
free:
#ifdef CONFIG_PCI_DOMAINS_GENERIC
- pci_bus_release_domain_nr(bus, parent);
+ pci_bus_release_domain_nr(parent, bus->domain_nr);
#endif
kfree(bus);
return err;
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -179,7 +179,7 @@ void pci_remove_root_bus(struct pci_bus
#ifdef CONFIG_PCI_DOMAINS_GENERIC
/* Release domain_nr if it was dynamically allocated */
if (host_bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
- pci_bus_release_domain_nr(bus, host_bridge->dev.parent);
+ pci_bus_release_domain_nr(host_bridge->dev.parent, bus->domain_nr);
#endif
pci_remove_bus(bus);
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1884,7 +1884,7 @@ static inline int acpi_pci_bus_find_doma
{ return 0; }
#endif
int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent);
-void pci_bus_release_domain_nr(struct pci_bus *bus, struct device *parent);
+void pci_bus_release_domain_nr(struct device *parent, int domain_nr);
#endif
/* Some architectures require additional setup to direct VGA traffic */
