From: Luo Meng luomeng12@huawei.com
stable inclusion from linux-4.19.160 commit 730b192ad262545a269483609f52d29bff503507
--------------------------------
[ Upstream commit 2801a5da5b25b7af9dd2addd19b2315c02d17b64 ]
Fix a mutex_unlock() issue where before copy_from_user() is not called mutex_locked.
Fixes: 4b1a29a7f542 ("error-injection: Support fault injection framework") Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Luo Meng luomeng12@huawei.com Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Signed-off-by: Alexei Starovoitov ast@kernel.org Acked-by: Masami Hiramatsu mhiramat@kernel.org Link: https://lore.kernel.org/bpf/160570737118.263807.8358435412898356284.stgit@de... Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- kernel/fail_function.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/kernel/fail_function.c b/kernel/fail_function.c index bc80a4e268c0..a52151a2291f 100644 --- a/kernel/fail_function.c +++ b/kernel/fail_function.c @@ -261,7 +261,7 @@ static ssize_t fei_write(struct file *file, const char __user *buffer,
if (copy_from_user(buf, buffer, count)) { ret = -EFAULT; - goto out; + goto out_free; } buf[count] = '\0'; sym = strstrip(buf); @@ -315,8 +315,9 @@ static ssize_t fei_write(struct file *file, const char __user *buffer, ret = count; } out: - kfree(buf); mutex_unlock(&fei_lock); +out_free: + kfree(buf); return ret; }