From: Oliver O'Halloran oohall@gmail.com
[ Upstream commit 1fb4124ca9d456656a324f1ee29b7bf942f59ac8 ]
When disabling virtual functions on an SR-IOV adapter we currently do not correctly remove the EEH state for the now-dead virtual functions. When removing the pci_dn that was created for the VF when SR-IOV was enabled we free the corresponding eeh_dev without removing it from the child device list of the eeh_pe that contained it. This can result in crashes due to the use-after-free.
Signed-off-by: Oliver O'Halloran oohall@gmail.com Reviewed-by: Sam Bobroff sbobroff@linux.ibm.com Tested-by: Sam Bobroff sbobroff@linux.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20190821062655.19735-1-oohall@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/kernel/pci_dn.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c index 5926934370702..c8f1b78fbd0e2 100644 --- a/arch/powerpc/kernel/pci_dn.c +++ b/arch/powerpc/kernel/pci_dn.c @@ -271,9 +271,22 @@ void remove_dev_pci_data(struct pci_dev *pdev) continue;
#ifdef CONFIG_EEH - /* Release EEH device for the VF */ + /* + * Release EEH state for this VF. The PCI core + * has already torn down the pci_dev for this VF, but + * we're responsible to removing the eeh_dev since it + * has the same lifetime as the pci_dn that spawned it. + */ edev = pdn_to_eeh_dev(pdn); if (edev) { + /* + * We allocate pci_dn's for the totalvfs count, + * but only only the vfs that were activated + * have a configured PE. + */ + if (edev->pe) + eeh_rmv_from_parent_pe(edev); + pdn->edev = NULL; kfree(edev); }