diff options
| author | Kent Gibson <warthog618@gmail.com> | 2020-10-05 15:02:46 +0800 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2020-10-08 22:57:16 +0200 |
| commit | f188ac1251b909c2d804a6fee54e4e360754c92f (patch) | |
| tree | eacd83d158b0926a4bbfb47713af0dd7ec4e8be5 | |
| parent | 8c270fbceba4e13c992ac138e51db217c4844ed6 (diff) | |
| download | linux-f188ac1251b909c2d804a6fee54e4e360754c92f.tar.gz | |
gpiolib: cdev: switch from kstrdup() to kstrndup()
Use kstrndup() to copy line labels from the userspace provided char
array, rather than ensuring the char array contains a null terminator
and using kstrdup().
Note that the length provided to kstrndup() still assumes that the char
array does contain a null terminator, so the maximum string length is one
less than the array. This is consistent with the previous behaviour.
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20201005070246.20927-1-warthog618@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | drivers/gpio/gpiolib-cdev.c | 27 |
1 files changed, 13 insertions, 14 deletions
diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 73386fcc252db9..94733aab322484 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -307,11 +307,11 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) lh->gdev = gdev; get_device(&gdev->dev); - /* Make sure this is terminated */ - handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0'; - if (strlen(handlereq.consumer_label)) { - lh->label = kstrdup(handlereq.consumer_label, - GFP_KERNEL); + if (handlereq.consumer_label[0] != '\0') { + /* label is only initialized if consumer_label is set */ + lh->label = kstrndup(handlereq.consumer_label, + sizeof(handlereq.consumer_label) - 1, + GFP_KERNEL); if (!lh->label) { ret = -ENOMEM; goto out_free_lh; @@ -1322,11 +1322,10 @@ static int linereq_create(struct gpio_device *gdev, void __user *ip) INIT_DELAYED_WORK(&lr->lines[i].work, debounce_work_func); } - /* Make sure this is terminated */ - ulr.consumer[sizeof(ulr.consumer)-1] = '\0'; - if (strlen(ulr.consumer)) { + if (ulr.consumer[0] != '\0') { /* label is only initialized if consumer is set */ - lr->label = kstrdup(ulr.consumer, GFP_KERNEL); + lr->label = kstrndup(ulr.consumer, sizeof(ulr.consumer) - 1, + GFP_KERNEL); if (!lr->label) { ret = -ENOMEM; goto out_free_linereq; @@ -1711,11 +1710,11 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip) le->gdev = gdev; get_device(&gdev->dev); - /* Make sure this is terminated */ - eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0'; - if (strlen(eventreq.consumer_label)) { - le->label = kstrdup(eventreq.consumer_label, - GFP_KERNEL); + if (eventreq.consumer_label[0] != '\0') { + /* label is only initialized if consumer_label is set */ + le->label = kstrndup(eventreq.consumer_label, + sizeof(eventreq.consumer_label) - 1, + GFP_KERNEL); if (!le->label) { ret = -ENOMEM; goto out_free_le; |