From 18a015bccf9e8927008d0a255c9f14b8ec15a648 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Wed, 22 Sep 2021 21:00:57 +0900 Subject: ksmbd: check protocol id in ksmbd_verify_smb_message() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When second smb2 pdu has invalid protocol id, ksmbd doesn't detect it and allow to process smb2 request. This patch add the check it in ksmbd_verify_smb_message() and don't use protocol id of smb2 request as protocol id of response. Reviewed-by: Ronnie Sahlberg Reviewed-by: Ralph Böhme Reported-by: Ronnie Sahlberg Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/ksmbd/smb2pdu.c | 2 +- fs/ksmbd/smb_common.c | 13 +++++++++---- fs/ksmbd/smb_common.h | 1 + 3 files changed, 11 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index f59f9b8be51c..fd9d5595a5ca 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -433,7 +433,7 @@ static void init_chained_smb2_rsp(struct ksmbd_work *work) work->compound_pfid = KSMBD_NO_FID; } memset((char *)rsp_hdr + 4, 0, sizeof(struct smb2_hdr) + 2); - rsp_hdr->ProtocolId = rcv_hdr->ProtocolId; + rsp_hdr->ProtocolId = SMB2_PROTO_NUMBER; rsp_hdr->StructureSize = SMB2_HEADER_STRUCTURE_SIZE; rsp_hdr->Command = rcv_hdr->Command; diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c index 43d3123d8b62..40f4fafa2e11 100644 --- a/fs/ksmbd/smb_common.c +++ b/fs/ksmbd/smb_common.c @@ -129,16 +129,22 @@ int ksmbd_lookup_protocol_idx(char *str) * * check for valid smb signature and packet direction(request/response) * - * Return: 0 on success, otherwise 1 + * Return: 0 on success, otherwise -EINVAL */ int ksmbd_verify_smb_message(struct ksmbd_work *work) { - struct smb2_hdr *smb2_hdr = work->request_buf; + struct smb2_hdr *smb2_hdr = work->request_buf + work->next_smb2_rcv_hdr_off; + struct smb_hdr *hdr; if (smb2_hdr->ProtocolId == SMB2_PROTO_NUMBER) return ksmbd_smb2_check_message(work); - return 0; + hdr = work->request_buf; + if (*(__le32 *)hdr->Protocol == SMB1_PROTO_NUMBER && + hdr->Command == SMB_COM_NEGOTIATE) + return 0; + + return -EINVAL; } /** @@ -265,7 +271,6 @@ static int ksmbd_negotiate_smb_dialect(void *buf) return BAD_PROT_ID; } -#define SMB_COM_NEGOTIATE 0x72 int ksmbd_init_smb_server(struct ksmbd_work *work) { struct ksmbd_conn *conn = work->conn; diff --git a/fs/ksmbd/smb_common.h b/fs/ksmbd/smb_common.h index 57c667c1be06..0a6af447cc45 100644 --- a/fs/ksmbd/smb_common.h +++ b/fs/ksmbd/smb_common.h @@ -210,6 +210,7 @@ FILE_READ_ATTRIBUTES | FILE_WRITE_ATTRIBUTES) #define SMB1_PROTO_NUMBER cpu_to_le32(0x424d53ff) +#define SMB_COM_NEGOTIATE 0x72 #define SMB1_CLIENT_GUID_SIZE (16) struct smb_hdr { -- cgit v1.2.3-58-ga151