This is a note to let you know that I've just added the patch titled powerpc/eeh: Null check uses of eeh_pe_bus_get to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-eeh-null-check-uses-of-eeh_pe_bus_get.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 04fec21c06e35b169a83e75a84a015ab4606bf5e Mon Sep 17 00:00:00 2001 From: Russell Currey <ruscur@xxxxxxxxxx> Date: Mon, 12 Sep 2016 14:17:22 +1000 Subject: powerpc/eeh: Null check uses of eeh_pe_bus_get From: Russell Currey <ruscur@xxxxxxxxxx> commit 04fec21c06e35b169a83e75a84a015ab4606bf5e upstream. eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE. Some callers don't check this, and can cause a null pointer dereference under certain circumstances. Fix this by checking NULL everywhere eeh_pe_bus_get() is called. Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event") Cc: stable@xxxxxxxxxxxxxxx # v3.11+ Signed-off-by: Russell Currey <ruscur@xxxxxxxxxx> Reviewed-by: Andrew Donnellan <andrew.donnellan@xxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/kernel/eeh_driver.c | 8 ++++++++ arch/powerpc/platforms/powernv/eeh-powernv.c | 5 +++++ 2 files changed, 13 insertions(+) --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -909,6 +909,14 @@ static void eeh_handle_special_event(voi /* Notify all devices to be down */ eeh_pe_state_clear(pe, EEH_PE_PRI_BUS); bus = eeh_pe_bus_get(phb_pe); + if (!bus) { + pr_err("%s: Cannot find PCI bus for " + "PHB#%d-PE#%x\n", + __func__, + pe->phb->global_number, + pe->addr); + break; + } eeh_pe_dev_traverse(pe, eeh_report_failure, NULL); pcibios_remove_pci_devices(bus); --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c @@ -956,6 +956,11 @@ static int pnv_eeh_reset(struct eeh_pe * } bus = eeh_pe_bus_get(pe); + if (!bus) { + pr_err("%s: Cannot find PCI bus for PHB#%d-PE#%x\n", + __func__, pe->phb->global_number, pe->addr); + return -EIO; + } if (pci_is_root_bus(bus) || pci_is_root_bus(bus->parent)) ret = pnv_eeh_root_reset(hose, option); Patches currently in stable-queue which might be from ruscur@xxxxxxxxxx are queue-4.4/powerpc-eeh-null-check-uses-of-eeh_pe_bus_get.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html