fail_function: switch to memdup_user_nul() helper

Use memdup_user_nul() helper instead of open-coding to simplify the code.

Yang Yingliang committed 4 years ago

Commit f81259c1 parent 9a151931 file · +4 −9Browse files

Showing the changes to kernel/fail_function.c (1 of 1 file). Show all

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@@ -247,15 +247,11 @@ static ssize_t fei_write(struct file file, const char __user buffer, · 246 unmodified lines
247	247	/* cut off if it is too long */
248	248	if (count > KSYM_NAME_LEN)
249	249	count = KSYM_NAME_LEN;
250		− buf = kmalloc(count + 1, GFP_KERNEL);
251		− if (!buf)
252		− return -ENOMEM;
253	250
254		− if (copy_from_user(buf, buffer, count)) {
255		− ret = -EFAULT;
256		− goto out_free;
257		− }
258		− buf[count] = '\0';
	251	+ buf = memdup_user_nul(buffer, count);
	252	+ if (IS_ERR(buf))
	253	+ return PTR_ERR(buf);
	254	+
259	255	sym = strstrip(buf);
260	256
261	257	mutex_lock(&fei_lock);
@@ -308,7 +304,6 @@ static ssize_t fei_write(struct file file, const char __user buffer, · 46 unmodified lines
308	304	}
309	305	out:
310	306	mutex_unlock(&fei_lock);
311		−out_free:
312	307	kfree(buf);
313	308	return ret;
314	309	}