From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: [PATCH] vfs: fix isize/pos/len checks for reflink & dedupe
Date: Sun, 18 Dec 2016 19:15:01 -0800 [thread overview]
Message-ID: <20161219031501.GB7311@birch.djwong.org> (raw)
Strengthen the checking of pos/len vs. i_size, clarify the return values
for the clone prep function, and remove pointless code.
Signed-off-by: Darrick J. WOng <darrick.wong@oracle.com>
---
fs/ocfs2/refcounttree.c | 2 +-
fs/read_write.c | 18 +++++++++++-------
fs/xfs/xfs_reflink.c | 2 +-
3 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index b18465e..21723dd 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -4835,7 +4835,7 @@ int ocfs2_reflink_remap_range(struct file *file_in,
ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out,
&len, is_dedupe);
- if (ret || len == 0)
+ if (ret <= 0)
goto out_unlock;
/* Lock out changes to the allocation maps and remap. */
diff --git a/fs/read_write.c b/fs/read_write.c
index dbf3f7f..434da26 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1671,6 +1671,9 @@ static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write)
* Check that the two inodes are eligible for cloning, the ranges make
* sense, and then flush all dirty data. Caller must ensure that the
* inodes have been locked against any other modifications.
+ *
+ * Returns: 0 for "nothing to clone", 1 for "something to clone", or
+ * the usual negative error code.
*/
int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
struct inode *inode_out, loff_t pos_out,
@@ -1697,17 +1700,15 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
/* Are we going all the way to the end? */
isize = i_size_read(inode_in);
- if (isize == 0) {
- *len = 0;
+ if (isize == 0)
return 0;
- }
/* Zero length dedupe exits immediately; reflink goes to EOF. */
if (*len == 0) {
- if (is_dedupe) {
- *len = 0;
+ if (is_dedupe || pos_in == isize)
return 0;
- }
+ else if (pos_in > isize)
+ return -EINVAL;
*len = isize - pos_in;
}
@@ -1771,7 +1772,7 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
return -EBADE;
}
- return 0;
+ return 1;
}
EXPORT_SYMBOL(vfs_clone_file_prep_inodes);
@@ -1958,6 +1959,9 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
goto out;
ret = 0;
+ if (off + len > i_size_read(src))
+ return -EINVAL;
+
/* pre-format output fields to sane values */
for (i = 0; i < count; i++) {
same->info[i].bytes_deduped = 0ULL;
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 43c0042..2a8ea32 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1215,7 +1215,7 @@ xfs_reflink_remap_range(
ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out,
&len, is_dedupe);
- if (ret || len == 0)
+ if (ret <= 0)
goto out_unlock;
trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out);
next reply other threads:[~2016-12-19 3:15 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-19 3:15 Darrick J. Wong [this message]
2016-12-19 10:11 ` [PATCH] vfs: fix isize/pos/len checks for reflink & dedupe Christoph Hellwig
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=20161219031501.GB7311@birch.djwong.org \
--to=darrick.wong@oracle.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=viro@ZenIV.linux.org.uk \
/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).