path: root/fs/cifs/smb2file.c
diff options
authorRoss Lagerwall <ross.lagerwall@citrix.com>2019-01-08 18:30:57 +0000
committerSteve French <stfrench@microsoft.com>2019-01-11 07:14:40 -0600
commitb9a74cde94957d82003fb9f7ab4777938ca851cd (patch)
treeccd9808334e6bc7ab6d53193aa7590f69de830ab /fs/cifs/smb2file.c
parentcifs: Limit memory used by lock request calls to a page (diff)
cifs: Fix potential OOB access of lock element array
If maxBuf is small but non-zero, it could result in a zero sized lock element array which we would then try and access OOB. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org>
Diffstat (limited to 'fs/cifs/smb2file.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c
index eff01ed6db0a..b204e84b87fb 100644
--- a/fs/cifs/smb2file.c
+++ b/fs/cifs/smb2file.c
@@ -122,10 +122,10 @@ smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
* Accessing maxBuf is racy with cifs_reconnect - need to store value
- * and check it for zero before using.
+ * and check it before using.
max_buf = tcon->ses->server->maxBuf;
- if (!max_buf)
+ if (max_buf < sizeof(struct smb2_lock_element))
return -EINVAL;
BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);