[PATCH] splice: fix possible memory leak in vmsplice_to_user().

[Leon Yu <chianglungyu@gmail.com>]

Since commit 6130f5315 ("switch vmsplice_to_user() to copy_page_to_iter()"),
rw_copy_check_uvector is used for sanity check, however, iov can be leaked if
that check failed.

So, fix it by handling this error path properly.

Signed-off-by: Leon Yu <chianglungyu@gmail.com>
---
 fs/splice.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/splice.c b/fs/splice.c
index 9bc07d2..b789328 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1546,7 +1546,7 @@ static long vmsplice_to_user(struct file *file, const struct iovec __user *uiov,
 	ret = rw_copy_check_uvector(READ, uiov, nr_segs,
 				    ARRAY_SIZE(iovstack), iovstack, &iov);
 	if (ret <= 0)
-		return ret;
+		goto out;
 
 	iov_iter_init(&iter, iov, nr_segs, count, 0);
 
@@ -1560,6 +1560,7 @@ static long vmsplice_to_user(struct file *file, const struct iovec __user *uiov,
 	ret = __splice_from_pipe(pipe, &sd, pipe_to_user);
 	pipe_unlock(pipe);
 
+out:
 	if (iov != iovstack)
 		kfree(iov);
 
-- 
1.9.2