There are two different issues fixed here: - On nun-NULL terminated input a random byte of memory would get flipped from '\n' to '\0'. - When printing the driver_override parameter when it is 4095 and 4094 bytes long the printing code would access invalid memory.
Signed-off-by: Sasha Levin <[email protected]> --- drivers/pci/pci-sysfs.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index aa012fb..be6b2b1 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -521,17 +521,17 @@ static ssize_t driver_override_store(struct device *dev, struct pci_dev *pdev = to_pci_dev(dev); char *driver_override, *old = pdev->driver_override, *cp; - if (count > PATH_MAX) + /* We need to keep extra room for a newline */ + if (count >= (PATH_MAX - 1)) return -EINVAL; driver_override = kstrndup(buf, count, GFP_KERNEL); if (!driver_override) return -ENOMEM; - cp = strchr(driver_override, '\n'); - if (cp) - *cp = '\0'; - + driver_override[count] = '\0'; + if (driver_override[count - 1] == '\n') + driver_override[count - 1] = 0; if (strlen(driver_override)) { pdev->driver_override = driver_override; } else { -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
