From: Christoph Hellwig <hch@infradead.org>
To: Lukas Czerner <lczerner@redhat.com>
Cc: hch@infradead.org, xfs@oss.sgi.com
Subject: Re: [PATCH v2] xfs: fix possible overflow in xfs_ioc_trim()
Date: Tue, 6 Sep 2011 11:33:01 -0400 [thread overview]
Message-ID: <20110906153301.GA21675@infradead.org> (raw)
In-Reply-To: <1315322977-22736-1-git-send-email-lczerner@redhat.com>
On Tue, Sep 06, 2011 at 05:29:37PM +0200, Lukas Czerner wrote:
> In xfs_ioc_trim it is possible that start+len might overflow. Fix it by
> decrementing the len so that start+len equals to the file system size in
> the worst case.
>
> Signed-off-by: Lukas Czerner <lczerner@redhat.com>
> @@ -146,6 +146,7 @@ xfs_ioc_trim(
> unsigned int granularity = q->limits.discard_granularity;
> struct fstrim_range range;
> xfs_fsblock_t start, len, minlen;
> + xfs_fsblock_t max_blks = mp->m_sb.sb_dblocks;
> xfs_agnumber_t start_agno, end_agno, agno;
> __uint64_t blocks_trimmed = 0;
> int error, last_error = 0;
> @@ -171,7 +172,8 @@ xfs_ioc_trim(
> start_agno = XFS_FSB_TO_AGNO(mp, start);
> if (start_agno >= mp->m_sb.sb_agcount)
> return -XFS_ERROR(EINVAL);
> -
> + if (len > max_blks)
> + len = max_blks - start;
Is this really the correct check?
Shouldn't it be
if (start + len > max_blks)
len = max_blks - start;
I'd also just use the mp->m_sb.sb_dblocks value directly instead
of assigning it to a local variable.
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
next prev parent reply other threads:[~2011-09-06 15:33 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-06 15:29 [PATCH v2] xfs: fix possible overflow in xfs_ioc_trim() Lukas Czerner
2011-09-06 15:33 ` Christoph Hellwig [this message]
2011-09-07 10:05 ` Lukas Czerner
2011-09-07 11:21 ` Christoph Hellwig
2011-09-07 12:26 ` Lukas Czerner
2011-09-20 13:36 ` Lukas Czerner
2011-09-20 17:12 ` Christoph Hellwig
2011-09-21 7:46 ` Lukas Czerner
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=20110906153301.GA21675@infradead.org \
--to=hch@infradead.org \
--cc=lczerner@redhat.com \
--cc=xfs@oss.sgi.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.