linux-unionfs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Chengguang Xu <cgxu519@mykernel.net>
To: miklos@szeredi.hu
Cc: linux-unionfs@vger.kernel.org, Chengguang Xu <cgxu519@mykernel.net>
Subject: [PATCH v2 2/3] ovl: check actual copy-up size
Date: Tue,  6 Apr 2021 20:02:44 +0800	[thread overview]
Message-ID: <20210406120245.1338326-2-cgxu519@mykernel.net> (raw)
In-Reply-To: <20210406120245.1338326-1-cgxu519@mykernel.net>

In order to simplify truncate operation on the file which
only has lower, we allow specifying larger size than lower
file when calling ovl_copy_up_data(), so we should check
actual copy size carefully before doing copy-up.

Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
---
 fs/overlayfs/copy_up.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 8b92b3ba3c46..a1a9a150405a 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -156,6 +156,9 @@ static int ovl_copy_up_data(struct ovl_fs *ofs, struct path *old,
 		goto out_fput;
 	}
 
+	len = (len <= i_size_read(file_inode(old_file))) ? len :
+				i_size_read(file_inode(old_file));
+
 	/* Try to use clone_file_range to clone up within the same fs */
 	cloned = do_clone_file_range(old_file, 0, new_file, 0, len, 0);
 	if (cloned == len)
-- 
2.27.0



  reply	other threads:[~2021-04-06 12:03 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-06 12:02 [PATCH v2 1/3] ovl: do not restore mtime on copy-up for regular file Chengguang Xu
2021-04-06 12:02 ` Chengguang Xu [this message]
2021-04-07  6:56   ` [PATCH v2 2/3] ovl: check actual copy-up size Amir Goldstein
2021-04-06 12:02 ` [PATCH v2 3/3] ovl: copy-up optimization for truncate Chengguang Xu
2021-04-07  7:52   ` Amir Goldstein
2021-04-08 13:23     ` Chengguang Xu
2021-04-08 14:40       ` Amir Goldstein
2021-04-09  3:00         ` Chengguang Xu
2021-04-09  5:50           ` Amir Goldstein
2021-04-09  8:02             ` Miklos Szeredi
2021-04-07  6:55 ` [PATCH v2 1/3] ovl: do not restore mtime on copy-up for regular file Amir Goldstein

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210406120245.1338326-2-cgxu519@mykernel.net \
    --to=cgxu519@mykernel.net \
    --cc=linux-unionfs@vger.kernel.org \
    --cc=miklos@szeredi.hu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).