Hi Maitainers
This patch is a fix in kceph module and should be backported to any
affected stable old kernels. And the original patch missed tagging
stable and got merged already months ago:
commit 7cb9994754f8a36ae9e5ec4597c5c4c2d6c03832
Author: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
Date: Fri Jul 1 10:52:27 2022 +0800
ceph: don't truncate file in atomic_open
Clear O_TRUNC from the flags sent in the MDS create request.
`atomic_open' is called before permission check. We should not do any
modification to the file here. The caller will do the truncation
afterward.
Fixes: 124e68e74099 ("ceph: file operations")
Signed-off-by: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
Reviewed-by: Xiubo Li <xiubli@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Just a single patch.
I am not very sure this is the correct way to do this, if anything else
I need to do to backport this to old kernels please let me know.
Thanks!
- Xiubo
On 01/07/2022 10:52, Hu Weiwen wrote:
Clear O_TRUNC from the flags sent in the MDS create request.
`atomic_open' is called before permission check. We should not do any
modification to the file here. The caller will do the truncation
afterward.
Fixes: 124e68e74099 ("ceph: file operations")
Signed-off-by: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
---
rebased onto ceph_client repo testing branch
fs/ceph/file.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 296fd1c7ece8..289e66e9cbb0 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -745,6 +745,11 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
err = ceph_wait_on_conflict_unlink(dentry);
if (err)
return err;
+ /*
+ * Do not truncate the file, since atomic_open is called before the
+ * permission check. The caller will do the truncation afterward.
+ */
+ flags &= ~O_TRUNC;
retry:
if (flags & O_CREAT) {
@@ -836,9 +841,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_new_inode = new_inode;
new_inode = NULL;
- err = ceph_mdsc_do_request(mdsc,
- (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
- req);
+ err = ceph_mdsc_do_request(mdsc, (flags & O_CREAT) ? dir : NULL, req);
if (err == -ENOENT) {
dentry = ceph_handle_snapdir(req, dentry);
if (IS_ERR(dentry)) {
