This patch fixes the sparse error in functionfs driver. drivers/usb/gadget/function/f_fs.c:400:44: error: bad constant experssion. Dynamic memory allocation through kcalloc is more safer than declaring variable array size, Fix this error by using kcalloc for memory allocation, Check if memory allocation is successful and return -ENOMEM on failure. Signed-off-by: Rohith Seelaboyina <rseelaboyina@xxxxxxxxxx> --- Changes in v3: - Follow kernel coding style to seperate variable declaration and assignment. Changes in v2: - Use kcalloc to allocate memory instead of using kmalloc and memset. drivers/usb/gadget/function/f_fs.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 63314ede7ba6..8af3f7906c83 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -397,10 +397,13 @@ static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf, * We are holding ffs->ev.waitq.lock and ffs->mutex and we need * to release them. */ - struct usb_functionfs_event events[n]; unsigned i = 0; + int ret; + struct usb_functionfs_event *events; - memset(events, 0, sizeof events); + events = kcalloc(n, sizeof(*events), GFP_KERNEL); + if (!events) + return -ENOMEM; do { events[i].type = ffs->ev.types[i]; @@ -421,8 +424,10 @@ static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf, spin_unlock_irq(&ffs->ev.waitq.lock); mutex_unlock(&ffs->mutex); - return unlikely(__copy_to_user(buf, events, sizeof events)) - ? -EFAULT : sizeof events; + ret = unlikely(__copy_to_user(buf, events, n * sizeof(*events))) + ? -EFAULT : n * sizeof(*events); + kfree(events); + return ret; } static ssize_t ffs_ep0_read(struct file *file, char __user *buf, -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html