This is a note to let you know that I've just added the patch titled PCI/sysfs: Fix double free in error path to the 4.19-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-sysfs-fix-double-free-in-error-path.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From aa382ffa705bea9931ec92b6f3c70e1fdb372195 Mon Sep 17 00:00:00 2001 From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> Date: Tue, 8 Nov 2022 17:05:59 -0600 Subject: PCI/sysfs: Fix double free in error path From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> commit aa382ffa705bea9931ec92b6f3c70e1fdb372195 upstream. When pci_create_attr() fails, pci_remove_resource_files() is called which will iterate over the res_attr[_wc] arrays and frees every non NULL entry. To avoid a double free here set the array entry only after it's clear we successfully initialized it. Fixes: b562ec8f74e4 ("PCI: Don't leak memory if sysfs_create_bin_file() fails") Link: https://lore.kernel.org/r/20221007070735.GX986@xxxxxxxxxxxxxx/ Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pci/pci-sysfs.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1289,11 +1289,9 @@ static int pci_create_attr(struct pci_de sysfs_bin_attr_init(res_attr); if (write_combine) { - pdev->res_attr_wc[num] = res_attr; sprintf(res_attr_name, "resource%d_wc", num); res_attr->mmap = pci_mmap_resource_wc; } else { - pdev->res_attr[num] = res_attr; sprintf(res_attr_name, "resource%d", num); if (pci_resource_flags(pdev, num) & IORESOURCE_IO) { res_attr->read = pci_read_resource_io; @@ -1309,10 +1307,17 @@ static int pci_create_attr(struct pci_de res_attr->size = pci_resource_len(pdev, num); res_attr->private = (void *)(unsigned long)num; retval = sysfs_create_bin_file(&pdev->dev.kobj, res_attr); - if (retval) + if (retval) { kfree(res_attr); + return retval; + } + + if (write_combine) + pdev->res_attr_wc[num] = res_attr; + else + pdev->res_attr[num] = res_attr; - return retval; + return 0; } /** Patches currently in stable-queue which might be from s.hauer@xxxxxxxxxxxxxx are queue-4.19/pci-sysfs-fix-double-free-in-error-path.patch