summary refs log tree commit diff
path: root/fs/cifs/file.c
diff options
context:
space:
mode:
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/file.c
parent92a8109e4d3a34fb6b115c9098b51767dc933444 (diff)
downloadlinux-b9a74cde94957d82003fb9f7ab4777938ca851cd.tar.gz
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/file.c')
-rw-r--r--fs/cifs/file.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 673f948e4760..5b6f8392d9db 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1132,10 +1132,10 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
 
 	/*
 	 * 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 smb_hdr) + sizeof(LOCKING_ANDX_RANGE))) {
 		free_xid(xid);
 		return -EINVAL;
 	}
@@ -1476,10 +1476,10 @@ cifs_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 smb_hdr) + sizeof(LOCKING_ANDX_RANGE)))
 		return -EINVAL;
 
 	BUILD_BUG_ON(sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE) >