From dbc3171194403d0d40e4bdeae666f6e76e428b53 Mon Sep 17 00:00:00 2001 From: Samasth Norway Ananda Date: Mon, 12 Aug 2024 13:26:59 -0700 Subject: [PATCH] x86/PCI: Check pcie_find_root_port() return for NULL If pcie_find_root_port() is unable to locate a Root Port, it will return NULL. Check the pointer for NULL before dereferencing it. This particular case is in a quirk for devices that are always below a Root Port, so this won't avoid a problem and doesn't need to be backported, but check as a matter of style and to prevent copy/paste mistakes. Link: https://lore.kernel.org/r/20240812202659.1649121-1-samasth.norway.ananda@oracle.com Signed-off-by: Samasth Norway Ananda [bhelgaas: drop Fixes: and explain why there's no problem in this case] Signed-off-by: Bjorn Helgaas Reviewed-by: Mario Limonciello --- arch/x86/pci/fixup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c index b33afb240601..98a9bb92d75c 100644 --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -980,7 +980,7 @@ static void amd_rp_pme_suspend(struct pci_dev *dev) return; rp = pcie_find_root_port(dev); - if (!rp->pm_cap) + if (!rp || !rp->pm_cap) return; rp->pme_support &= ~((PCI_PM_CAP_PME_D3hot|PCI_PM_CAP_PME_D3cold) >> @@ -994,7 +994,7 @@ static void amd_rp_pme_resume(struct pci_dev *dev) u16 pmc; rp = pcie_find_root_port(dev); - if (!rp->pm_cap) + if (!rp || !rp->pm_cap) return; pci_read_config_word(rp, rp->pm_cap + PCI_PM_PMC, &pmc);