From c954acc0007bf2a33a34505e21bc5d617a2fe2aa Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Tue, 29 Nov 2016 16:14:43 -0800 Subject: [PATCH] CIFS: Fix a possible memory corruption in push locks commit e3d240e9d505fc67f8f8735836df97a794bbd946 upstream. If maxBuf is not 0 but less than a size of SMB2 lock structure we can end up with a memory corruption. Signed-off-by: Pavel Shilovsky Signed-off-by: Greg Kroah-Hartman --- fs/cifs/smb2file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c index f9e766f..b2aff0c 100644 --- a/fs/cifs/smb2file.c +++ b/fs/cifs/smb2file.c @@ -260,7 +260,7 @@ smb2_push_mandatory_locks(struct cifsFileInfo *cfile) * and check it for zero before using. */ max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf; - if (!max_buf) { + if (max_buf < sizeof(struct smb2_lock_element)) { free_xid(xid); return -EINVAL; } -- 2.7.4