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 5.15-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-5.15 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
@@ -1179,11 +1179,9 @@ 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;
@@ -1201,10 +1199,17 @@ 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-5.15/pci-sysfs-fix-double-free-in-error-path.patch
