From: Xi Wang <xi.wang@gmail.com>
To: Sage Weil <sage@newdream.net>
Cc: ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org,
Xi Wang <xi.wang@gmail.com>
Subject: [PATCH] ceph: fix overflow check in build_snap_context()
Date: Thu, 16 Feb 2012 11:56:29 -0500 [thread overview]
Message-ID: <1329411389-13492-1-git-send-email-xi.wang@gmail.com> (raw)
The overflow check for a + n * b should be (n > (ULONG_MAX - a) / b),
rather than (n > ULONG_MAX / b - a).
Signed-off-by: Xi Wang <xi.wang@gmail.com>
---
fs/ceph/snap.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index a559c80..f04c096 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -331,7 +331,7 @@ static int build_snap_context(struct ceph_snap_realm *realm)
/* alloc new snap context */
err = -ENOMEM;
- if (num > ULONG_MAX / sizeof(u64) - sizeof(*snapc))
+ if (num > (ULONG_MAX - sizeof(*snapc)) / sizeof(u64))
goto fail;
snapc = kzalloc(sizeof(*snapc) + num*sizeof(u64), GFP_NOFS);
if (!snapc)
--
1.7.5.4
reply other threads:[~2012-02-16 16:59 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=1329411389-13492-1-git-send-email-xi.wang@gmail.com \
--to=xi.wang@gmail.com \
--cc=ceph-devel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=sage@newdream.net \
/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
all inboxes | Powered by JetHome®