6.11-stable review patch. If anyone has any objections, please let me know.
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From: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org
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@stanl... Link: https://lore.kernel.org/linux-pci/20240912053025.25314-1-manivannan.sadhasiv... Reported-by: Dan Carpenter dan.carpenter@linaro.org Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński kwilczynski@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 */