From: Marios Makassikis mmakassikis@freebox.fr
mainline inclusion from mainline-5.15-rc7 commit 0d994cd482ee4e8e851388a70869beee51be1c54 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I60T7G CVE: NA
Reference: https://git.kernel.org/torvalds/linux/c/0d994cd482ee
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Make sure the security buffer's length/offset are valid with regards to the packet length.
Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Marios Makassikis mmakassikis@freebox.fr Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zhong Jinghua zhongjinghua@huawei.com --- fs/ksmbd/auth.c | 16 ++++++++------- fs/ksmbd/smb2pdu.c | 51 ++++++++++++++++++++++++++++------------------ 2 files changed, 40 insertions(+), 27 deletions(-)
diff --git a/fs/ksmbd/auth.c b/fs/ksmbd/auth.c index 71c989f1568d..30a92ddc1817 100644 --- a/fs/ksmbd/auth.c +++ b/fs/ksmbd/auth.c @@ -298,8 +298,8 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob, int blob_len, struct ksmbd_session *sess) { char *domain_name; - unsigned int lm_off, nt_off; - unsigned short nt_len; + unsigned int nt_off, dn_off; + unsigned short nt_len, dn_len; int ret;
if (blob_len < sizeof(struct authenticate_message)) { @@ -314,15 +314,17 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob, return -EINVAL; }
- lm_off = le32_to_cpu(authblob->LmChallengeResponse.BufferOffset); nt_off = le32_to_cpu(authblob->NtChallengeResponse.BufferOffset); nt_len = le16_to_cpu(authblob->NtChallengeResponse.Length); + dn_off = le32_to_cpu(authblob->DomainName.BufferOffset); + dn_len = le16_to_cpu(authblob->DomainName.Length); + + if (blob_len < (u64)dn_off + dn_len || blob_len < (u64)nt_off + nt_len) + return -EINVAL;
/* TODO : use domain name that imported from configuration file */ - domain_name = smb_strndup_from_utf16((const char *)authblob + - le32_to_cpu(authblob->DomainName.BufferOffset), - le16_to_cpu(authblob->DomainName.Length), true, - sess->conn->local_nls); + domain_name = smb_strndup_from_utf16((const char *)authblob + dn_off, + dn_len, true, sess->conn->local_nls); if (IS_ERR(domain_name)) return PTR_ERR(domain_name);
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 82677e282af0..37da97576669 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -1257,19 +1257,13 @@ static int generate_preauth_hash(struct ksmbd_work *work) return 0; }
-static int decode_negotiation_token(struct ksmbd_work *work, - struct negotiate_message *negblob) +static int decode_negotiation_token(struct ksmbd_conn *conn, + struct negotiate_message *negblob, + size_t sz) { - struct ksmbd_conn *conn = work->conn; - struct smb2_sess_setup_req *req; - int sz; - if (!conn->use_spnego) return -EINVAL;
- req = work->request_buf; - sz = le16_to_cpu(req->SecurityBufferLength); - if (ksmbd_decode_negTokenInit((char *)negblob, sz, conn)) { if (ksmbd_decode_negTokenTarg((char *)negblob, sz, conn)) { conn->auth_mechs |= KSMBD_AUTH_NTLMSSP; @@ -1281,9 +1275,9 @@ static int decode_negotiation_token(struct ksmbd_work *work, }
static int ntlm_negotiate(struct ksmbd_work *work, - struct negotiate_message *negblob) + struct negotiate_message *negblob, + size_t negblob_len) { - struct smb2_sess_setup_req *req = work->request_buf; struct smb2_sess_setup_rsp *rsp = work->response_buf; struct challenge_message *chgblob; unsigned char *spnego_blob = NULL; @@ -1292,8 +1286,7 @@ static int ntlm_negotiate(struct ksmbd_work *work, int sz, rc;
ksmbd_debug(SMB, "negotiate phase\n"); - sz = le16_to_cpu(req->SecurityBufferLength); - rc = ksmbd_decode_ntlmssp_neg_blob(negblob, sz, work->sess); + rc = ksmbd_decode_ntlmssp_neg_blob(negblob, negblob_len, work->sess); if (rc) return rc;
@@ -1361,12 +1354,23 @@ static struct ksmbd_user *session_user(struct ksmbd_conn *conn, struct authenticate_message *authblob; struct ksmbd_user *user; char *name; - int sz; + unsigned int auth_msg_len, name_off, name_len, secbuf_len;
+ secbuf_len = le16_to_cpu(req->SecurityBufferLength); + if (secbuf_len < sizeof(struct authenticate_message)) { + ksmbd_debug(SMB, "blob len %d too small\n", secbuf_len); + return NULL; + } authblob = user_authblob(conn, req); - sz = le32_to_cpu(authblob->UserName.BufferOffset); - name = smb_strndup_from_utf16((const char *)authblob + sz, - le16_to_cpu(authblob->UserName.Length), + name_off = le32_to_cpu(authblob->UserName.BufferOffset); + name_len = le16_to_cpu(authblob->UserName.Length); + auth_msg_len = le16_to_cpu(req->SecurityBufferOffset) + secbuf_len; + + if (auth_msg_len < (u64)name_off + name_len) + return NULL; + + name = smb_strndup_from_utf16((const char *)authblob + name_off, + name_len, true, conn->local_nls); if (IS_ERR(name)) { @@ -1612,6 +1616,7 @@ int smb2_sess_setup(struct ksmbd_work *work) struct smb2_sess_setup_rsp *rsp = work->response_buf; struct ksmbd_session *sess; struct negotiate_message *negblob; + unsigned int negblob_len, negblob_off; int rc = 0;
ksmbd_debug(SMB, "Received request for session setup\n"); @@ -1692,10 +1697,16 @@ int smb2_sess_setup(struct ksmbd_work *work) if (sess->state == SMB2_SESSION_EXPIRED) sess->state = SMB2_SESSION_IN_PROGRESS;
+ negblob_off = le16_to_cpu(req->SecurityBufferOffset); + negblob_len = le16_to_cpu(req->SecurityBufferLength); + if (negblob_off < (offsetof(struct smb2_sess_setup_req, Buffer) - 4) || + negblob_len < offsetof(struct negotiate_message, NegotiateFlags)) + return -EINVAL; + negblob = (struct negotiate_message *)((char *)&req->hdr.ProtocolId + - le16_to_cpu(req->SecurityBufferOffset)); + negblob_off);
- if (decode_negotiation_token(work, negblob) == 0) { + if (decode_negotiation_token(conn, negblob, negblob_len) == 0) { if (conn->mechToken) negblob = (struct negotiate_message *)conn->mechToken; } @@ -1719,7 +1730,7 @@ int smb2_sess_setup(struct ksmbd_work *work) sess->Preauth_HashValue = NULL; } else if (conn->preferred_auth_mech == KSMBD_AUTH_NTLMSSP) { if (negblob->MessageType == NtLmNegotiate) { - rc = ntlm_negotiate(work, negblob); + rc = ntlm_negotiate(work, negblob, negblob_len); if (rc) goto out_err; rsp->hdr.Status =