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| author | Jerome Marchand <jmarchan@redhat.com> | 2016-05-26 12:52:25 +0300 |
|---|---|---|
| committer | Steve French <smfrench@gmail.com> | 2016-06-24 07:45:07 +0300 |
| commit | b8da344b74c822e966c6d19d6b2321efe82c5d97 (patch) | |
| tree | f4b6a50200af4e957e3ba0872e3555b74be21679 /fs/cifs/smb2pdu.c | |
| parent | 202d772ba02b1deb8835a631cd8255943d1906a0 (diff) | |
| download | linux-b8da344b74c822e966c6d19d6b2321efe82c5d97.tar.xz | |
cifs: dynamic allocation of ntlmssp blob
In sess_auth_rawntlmssp_authenticate(), the ntlmssp blob is allocated
statically and its size is an "empirical" 5*sizeof(struct
_AUTHENTICATE_MESSAGE) (320B on x86_64). I don't know where this value
comes from or if it was ever appropriate, but it is currently
insufficient: the user and domain name in UTF16 could take 1kB by
themselves. Because of that, build_ntlmssp_auth_blob() might corrupt
memory (out-of-bounds write). The size of ntlmssp_blob in
SMB2_sess_setup() is too small too (sizeof(struct _NEGOTIATE_MESSAGE)
+ 500).
This patch allocates the blob dynamically in
build_ntlmssp_auth_blob().
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Diffstat (limited to 'fs/cifs/smb2pdu.c')
| -rw-r--r-- | fs/cifs/smb2pdu.c | 10 |
1 files changed, 2 insertions, 8 deletions
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 8f38e33d365b..c3e61a7a7c7c 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -588,7 +588,7 @@ SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses, u16 blob_length = 0; struct key *spnego_key = NULL; char *security_blob = NULL; - char *ntlmssp_blob = NULL; + unsigned char *ntlmssp_blob = NULL; bool use_spnego = false; /* else use raw ntlmssp */ cifs_dbg(FYI, "Session Setup\n"); @@ -713,13 +713,7 @@ ssetup_ntlmssp_authenticate: iov[1].iov_len = blob_length; } else if (phase == NtLmAuthenticate) { req->hdr.SessionId = ses->Suid; - ntlmssp_blob = kzalloc(sizeof(struct _NEGOTIATE_MESSAGE) + 500, - GFP_KERNEL); - if (ntlmssp_blob == NULL) { - rc = -ENOMEM; - goto ssetup_exit; - } - rc = build_ntlmssp_auth_blob(ntlmssp_blob, &blob_length, ses, + rc = build_ntlmssp_auth_blob(&ntlmssp_blob, &blob_length, ses, nls_cp); if (rc) { cifs_dbg(FYI, "build_ntlmssp_auth_blob failed %d\n", |