From: Greg Kroah-Hartman Date: Mon, 28 Dec 2020 11:53:02 +0000 (+0100) Subject: 4.9-stable patches X-Git-Tag: v4.4.249~12 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4d56a3a9454dfa098d866346463f524e06020fa8;p=thirdparty%2Fkernel%2Fstable-queue.git 4.9-stable patches added patches: pci-fix-pci_slot_release-null-pointer-dereference.patch --- diff --git a/queue-4.9/pci-fix-pci_slot_release-null-pointer-dereference.patch b/queue-4.9/pci-fix-pci_slot_release-null-pointer-dereference.patch new file mode 100644 index 00000000000..d8f4cedf1e5 --- /dev/null +++ b/queue-4.9/pci-fix-pci_slot_release-null-pointer-dereference.patch @@ -0,0 +1,65 @@ +From 4684709bf81a2d98152ed6b610e3d5c403f9bced Mon Sep 17 00:00:00 2001 +From: Jubin Zhong +Date: Wed, 2 Dec 2020 10:33:42 +0800 +Subject: PCI: Fix pci_slot_release() NULL pointer dereference + +From: Jubin Zhong + +commit 4684709bf81a2d98152ed6b610e3d5c403f9bced upstream. + +If kobject_init_and_add() fails, pci_slot_release() is called to delete +slot->list from parent->slots. But slot->list hasn't been initialized +yet, so we dereference a NULL pointer: + + Unable to handle kernel NULL pointer dereference at virtual address +00000000 + ... + CPU: 10 PID: 1 Comm: swapper/0 Not tainted 4.4.240 #197 + task: ffffeb398a45ef10 task.stack: ffffeb398a470000 + PC is at __list_del_entry_valid+0x5c/0xb0 + LR is at pci_slot_release+0x84/0xe4 + ... + __list_del_entry_valid+0x5c/0xb0 + pci_slot_release+0x84/0xe4 + kobject_put+0x184/0x1c4 + pci_create_slot+0x17c/0x1b4 + __pci_hp_initialize+0x68/0xa4 + pciehp_probe+0x1a4/0x2fc + pcie_port_probe_service+0x58/0x84 + driver_probe_device+0x320/0x470 + +Initialize slot->list before calling kobject_init_and_add() to avoid this. + +Fixes: 8a94644b440e ("PCI: Fix pci_create_slot() reference count leak") +Link: https://lore.kernel.org/r/1606876422-117457-1-git-send-email-zhongjubin@huawei.com +Signed-off-by: Jubin Zhong +Signed-off-by: Bjorn Helgaas +Cc: stable@vger.kernel.org # v5.9+ +Signed-off-by: Greg Kroah-Hartman + +--- + drivers/pci/slot.c | 6 +++--- + 1 file changed, 3 insertions(+), 3 deletions(-) + +--- a/drivers/pci/slot.c ++++ b/drivers/pci/slot.c +@@ -307,6 +307,9 @@ placeholder: + goto err; + } + ++ INIT_LIST_HEAD(&slot->list); ++ list_add(&slot->list, &parent->slots); ++ + err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL, + "%s", slot_name); + if (err) { +@@ -314,9 +317,6 @@ placeholder: + goto err; + } + +- INIT_LIST_HEAD(&slot->list); +- list_add(&slot->list, &parent->slots); +- + down_read(&pci_bus_sem); + list_for_each_entry(dev, &parent->devices, bus_list) + if (PCI_SLOT(dev->devfn) == slot_nr) diff --git a/queue-4.9/series b/queue-4.9/series index ec06a4c75e5..7a65e5502e6 100644 --- a/queue-4.9/series +++ b/queue-4.9/series @@ -173,3 +173,4 @@ iio-adc-rockchip_saradc-fix-missing-clk_disable_unprepare-on-error-in-rockchip_s iio-pressure-mpl3115-force-alignment-of-buffer.patch clk-mvebu-a3700-fix-the-xtal-mode-pin-to-mpp1_9.patch xen-blkback-set-ring-xenblkd-to-null-after-kthread_stop.patch +pci-fix-pci_slot_release-null-pointer-dereference.patch