From: Christoph Probst <kernel@probst.it>
To: linux-cifs@vger.kernel.org
Cc: Steve French <sfrench@samba.org>,
samba-technical@lists.samba.org, linux-kernel@vger.kernel.org,
Christoph Probst <kernel@probst.it>
Subject: [PATCH] cifs: fix strcat buffer overflow in smb21_set_oplock_level()
Date: Mon, 6 May 2019 17:16:32 +0200 [thread overview]
Message-ID: <1557155792-2703-1-git-send-email-kernel@probst.it> (raw)
Change strcat to strcpy in the "None" case as it is never valid to append
"None" to any other message. It may also overflow char message[5], in a
race condition on cinode if cinode->oplock is unset by another thread
after "RHW" or "RH" had been written to message.
Signed-off-by: Christoph Probst <kernel@probst.it>
---
fs/cifs/smb2ops.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index c36ff0d..5fd5567 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2936,7 +2936,7 @@ smb21_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,
strcat(message, "W");
}
if (!cinode->oplock)
- strcat(message, "None");
+ strcpy(message, "None");
cifs_dbg(FYI, "%s Lease granted on inode %p\n", message,
&cinode->vfs_inode);
}
--
2.1.4
next reply other threads:[~2019-05-06 15:25 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-06 15:16 Christoph Probst [this message]
2019-05-06 16:53 ` [PATCH] cifs: fix strcat buffer overflow in smb21_set_oplock_level() Steve French
2019-05-06 16:56 ` Jeremy Allison
2019-05-06 17:02 ` Steve French
2019-05-06 19:03 ` Pavel Shilovsky
2019-05-06 21:18 ` Steve French
2019-05-07 6:10 ` Christoph Probst
2019-05-07 11:02 ` David Laight
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=1557155792-2703-1-git-send-email-kernel@probst.it \
--to=kernel@probst.it \
--cc=linux-cifs@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=samba-technical@lists.samba.org \
--cc=sfrench@samba.org \
/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).