[PATCH 04/20] PCI/sysfs: Add CAP_SYS_ADMIN check to __resource_resize_store()
Krzysztof Wilczyński <[email protected]>
| Newsgroups | org.kernel.vger.linux-alpha,org.kernel.vger.linux-pci,org.ozlabs.lists.linuxppc-dev |
|---|---|
| Message-ID | <[email protected]> |
Currently, the __resource_resize_store() allows writing to the resourceN_resize sysfs attribute to change a BAR's size without checking for capabilities, currently relying only on the file access check. Resizing a BAR modifies PCI device configuration and can disrupt active drivers. After the upcoming conversion to static attributes, it will also trigger resource file updates via sysfs_update_groups(). Thus, add a CAP_SYS_ADMIN check to prevent unprivileged users from performing BAR resize operations. Signed-off-by: Krzysztof Wilczyński <[email protected]> --- drivers/pci/pci-sysfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index ac4e7c516e78..6b8c8e62f68a 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1619,6 +1619,9 @@ static ssize_t __resource_resize_store(struct device *dev, int n, int ret; u16 cmd; + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (kstrtoul(buf, 0, &size) < 0) return -EINVAL; -- 2.53.0