On 10/7/23 16:52, Dan Carpenter wrote:
In this code "ret" is type long and "src_objlen" is unsigned int. The
problem is that on 32bit systems, when we do the comparison signed longs
are type promoted to unsigned int. So negative error codes from
do_splice_direct() are treated as success instead of failure.
Fixes: 1b0c3b9f91f0 ("ceph: re-org copy_file_range and fix some error paths")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
32bit is so weird and ancient. It's strange to think that unsigned int
has more positive bits than signed long.
fs/ceph/file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index b1da02f5dbe3..b5f8038065d7 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -2969,7 +2969,7 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,
ret = do_splice_direct(src_file, &src_off, dst_file,
&dst_off, src_objlen, flags);
/* Abort on short copies or on error */
- if (ret < src_objlen) {
+ if (ret < (long)src_objlen) {
dout("Failed partial copy (%zd)\n", ret);
goto out;
}
Good catch and makes sense to me.
I also ran a test in 64bit system, the output is the same too:
int x = -1
unsigned int y = 2
x > y
Reviewed-by: Xiubo Li <xiubli@xxxxxxxxxx>
Thanks
- Xiubo
