This is a note to let you know that I've just added the patch titled PCI/MSI: Destroy sysfs before freeing entries to the 5.4-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: pci-msi-destroy-sysfs-before-freeing-entries.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 3735459037114d31e5acd9894fad9aed104231a0 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Date: Tue, 9 Nov 2021 14:53:57 +0100 Subject: PCI/MSI: Destroy sysfs before freeing entries From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> commit 3735459037114d31e5acd9894fad9aed104231a0 upstream. free_msi_irqs() frees the MSI entries before destroying the sysfs entries which are exposing them. Nothing prevents a concurrent free while a sysfs file is read and accesses the possibly freed entry. Move the sysfs release ahead of freeing the entries. Fixes: 1c51b50c2995 ("PCI/MSI: Export MSI mode using attributes, not kobjects") Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Bjorn Helgaas <helgaas@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/87sfw5305m.ffs@tglx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pci/msi.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -395,18 +395,6 @@ static void free_msi_irqs(struct pci_dev for (i = 0; i < entry->nvec_used; i++) BUG_ON(irq_has_action(entry->irq + i)); - pci_msi_teardown_msi_irqs(dev); - - list_for_each_entry_safe(entry, tmp, msi_list, list) { - if (entry->msi_attrib.is_msix) { - if (list_is_last(&entry->list, msi_list)) - iounmap(entry->mask_base); - } - - list_del(&entry->list); - free_msi_entry(entry); - } - if (dev->msi_irq_groups) { sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups); msi_attrs = dev->msi_irq_groups[0]->attrs; @@ -422,6 +410,18 @@ static void free_msi_irqs(struct pci_dev kfree(dev->msi_irq_groups); dev->msi_irq_groups = NULL; } + + pci_msi_teardown_msi_irqs(dev); + + list_for_each_entry_safe(entry, tmp, msi_list, list) { + if (entry->msi_attrib.is_msix) { + if (list_is_last(&entry->list, msi_list)) + iounmap(entry->mask_base); + } + + list_del(&entry->list); + free_msi_entry(entry); + } } static void pci_intx_for_msi(struct pci_dev *dev, int enable) Patches currently in stable-queue which might be from tglx@xxxxxxxxxxxxx are queue-5.4/pci-add-msi-masking-quirk-for-nvidia-ion-ahci.patch queue-5.4/pci-msi-deal-with-devices-lying-about-their-msi-mask-capability.patch queue-5.4/pci-msi-destroy-sysfs-before-freeing-entries.patch