[PATCH v2] fs/ceph/file: fix memory leaks in __ceph_sync_read()

[Max Kellermann]

In two `break` statements, the call to ceph_release_page_vector() was
missing, leaking the allocation from ceph_alloc_page_vector().

Instead of adding the missing ceph_release_page_vector() calls, the
Ceph maintainers preferred to transfer page ownership to the
`ceph_osd_request` by passing `own_pages=true` to
osd_req_op_extent_osd_data_pages().  This requires postponing the
ceph_osdc_put_request() call until after the block that accesses the
`pages`.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Max Kellermann <max.kellermann@xxxxxxxxx>
---
 fs/ceph/file.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 4b8d59ebda00..ce342a5d4b8b 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1127,7 +1127,7 @@ ssize_t __ceph_sync_read(struct inode *inode, loff_t *ki_pos,
 
 		osd_req_op_extent_osd_data_pages(req, 0, pages, read_len,
 						 offset_in_page(read_off),
-						 false, false);
+						 false, true);
 
 		op = &req->r_ops[0];
 		if (sparse) {
@@ -1186,8 +1186,6 @@ ssize_t __ceph_sync_read(struct inode *inode, loff_t *ki_pos,
 			ret = min_t(ssize_t, fret, len);
 		}
 
-		ceph_osdc_put_request(req);
-
 		/* Short read but not EOF? Zero out the remainder. */
 		if (ret >= 0 && ret < len && (off + ret < i_size)) {
 			int zlen = min(len - ret, i_size - off - ret);
@@ -1221,7 +1219,8 @@ ssize_t __ceph_sync_read(struct inode *inode, loff_t *ki_pos,
 				break;
 			}
 		}
-		ceph_release_page_vector(pages, num_pages);
+
+		ceph_osdc_put_request(req);
 
 		if (ret < 0) {
 			if (ret == -EBLOCKLISTED)
-- 
2.45.2