From: Hu Weiwen sehuww@mail.scut.edu.cn
stable inclusion from stable-v5.10.148 commit b23b0cd57e2cebd40ea1ae2a96b5ede67392dab2 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0WL
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 7cb9994754f8a36ae9e5ec4597c5c4c2d6c03832 upstream.
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@mail.scut.edu.cn Reviewed-by: Xiubo Li xiubli@redhat.com Signed-off-by: Ilya Dryomov idryomov@gmail.com [Xiubo: fixed a trivial conflict for 5.10 backport] Signed-off-by: Xiubo Li xiubli@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Jialin Zhang zhangjialin11@huawei.com Reviewed-by: Zheng Zengkai zhengzengkai@huawei.com --- fs/ceph/file.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 93d986856f1c..943655e36a79 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -703,6 +703,12 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, if (dentry->d_name.len > NAME_MAX) return -ENAMETOOLONG;
+ /* + * Do not truncate the file, since atomic_open is called before the + * permission check. The caller will do the truncation afterward. + */ + flags &= ~O_TRUNC; + if (flags & O_CREAT) { if (ceph_quota_is_max_files_exceeded(dir)) return -EDQUOT; @@ -769,9 +775,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, }
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); - 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); err = ceph_handle_snapdir(req, dentry, err); if (err) goto out_req;