diff options
author | Ross Lagerwall <ross.lagerwall@citrix.com> | 2019-01-08 18:30:57 +0000 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-16 22:16:10 +0100 |
commit | 9c87abaf4d12413531ce689b781120ebaeeef044 (patch) | |
tree | 1cffc5e67c1a89e383bcaca21acf3a80d231641e | |
parent | 05ce0d9d5600b88f72427fc93613ef09006b3f91 (diff) |
cifs: Fix potential OOB access of lock element array
commit b9a74cde94957d82003fb9f7ab4777938ca851cd upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | fs/cifs/file.c | 8 | ||||
-rw-r--r-- | fs/cifs/smb2file.c | 4 |
2 files changed, 6 insertions, 6 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 0141aba9eca6..026b399af215 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -1073,10 +1073,10 @@ 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; } @@ -1404,10 +1404,10 @@ 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; max_num = (max_buf - sizeof(struct smb_hdr)) / diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c index b2aff0c6f22c..b7885dc0d9bb 100644 --- a/fs/cifs/smb2file.c +++ b/fs/cifs/smb2file.c @@ -123,10 +123,10 @@ 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; max_num = max_buf / sizeof(struct smb2_lock_element); |