[PATCH v2] vfs: generic_copy_file_checks should return EINVAL when source offset is beyond EOF

[Dai Ngo <dai.ngo@xxxxxxxxxx>]

Fix by returning -EINVAL instead of 0, per man page of copy_file_range,
when the requested range extends beyond the end of the source file.
Problem was discovered by subtest inter11 of nfstest_ssc.

Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
---
 fs/read_write.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/read_write.c b/fs/read_write.c
index 75f764b43418..438c00910716 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1445,7 +1445,7 @@ static int generic_copy_file_checks(struct file *file_in, loff_t pos_in,
 	/* Shorten the copy to EOF */
 	size_in = i_size_read(inode_in);
 	if (pos_in >= size_in)
-		count = 0;
+		count = -EINVAL;
 	else
 		count = min(count, size_in - (uint64_t)pos_in);
 
-- 
2.9.5