[PATCH 5.10.y 2/3] cifs: SMB1 split: Create smb1proto.h for SMB1 declarations
From: Sasha Levin
Date: Tue Sep 08 2026 - 08:38:30 EST
From: David Howells <dhowells@xxxxxxxxxx>
[ Upstream commit 86c666506ea2c42649879eeac7f29e7bedef2f23 ]
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Steve French <sfrench@xxxxxxxxx>
cc: Paulo Alcantara <pc@xxxxxxxxxxxxx>
cc: Enzo Matsumiya <ematsumiya@xxxxxxx>
cc: linux-cifs@xxxxxxxxxxxxxxx
cc: linux-fsdevel@xxxxxxxxxxxxxxx
cc: linux-kernel@xxxxxxxxxxxxxxx
Acked-by: Enzo Matsumiya <ematsumiya@xxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
[ sashal: Reduced backport -- upstream 86c666506ea2c touches 3 file(s), this
backport carries 8. Not backported here:
fs/smb/client/cifsglob.h
fs/smb/client/cifsproto.h
fs/smb/client/smb1proto.h
This note is generated from the file lists only; see the resolution record
for the reasoning. ]
Stable-dep-of: 730d0bb19507 ("smb: client: fix UAF and buffer leak in cifs_check_trans2() for malformed secondary T2")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/cifs/Makefile | 2 +-
fs/cifs/cifsglob.h | 2 -
fs/cifs/cifsproto.h | 11 +--
fs/cifs/fs_context.c | 1 +
fs/cifs/smb1ops.c | 171 --------------------------------
fs/cifs/smb1proto.h | 40 ++++++++
fs/cifs/smb1transport.c | 3 +
fs/smb/client/smb1transport.c | 180 ++++++++++++++++++++++++++++++++++
8 files changed, 226 insertions(+), 184 deletions(-)
create mode 100644 fs/cifs/smb1proto.h
create mode 100644 fs/cifs/smb1transport.c
create mode 100644 fs/smb/client/smb1transport.c
diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
index cd17d0e50f2a1..f992815ce5041 100644
--- a/fs/cifs/Makefile
+++ b/fs/cifs/Makefile
@@ -8,7 +8,7 @@ obj-$(CONFIG_CIFS) += cifs.o
cifs-y := trace.o cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o \
inode.o link.o misc.o netmisc.o smbencrypt.o transport.o asn1.o \
cifs_unicode.o nterr.o cifsencrypt.o \
- readdir.o ioctl.o sess.o export.o smb1ops.o winucase.o \
+ readdir.o ioctl.o sess.o export.o smb1ops.o smb1transport.o winucase.o \
smb2ops.o smb2maperror.o smb2transport.o \
smb2misc.o smb2pdu.o smb2inode.o smb2file.o cifsacl.o fs_context.o
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index d0905aa0b04cd..98c9b97480136 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1990,8 +1990,6 @@ extern mempool_t *cifs_mid_poolp;
#define SMB1_VERSION_STRING "1.0"
#define SMB20_VERSION_STRING "2.0"
#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
-extern struct smb_version_operations smb1_operations;
-extern struct smb_version_values smb1_values;
extern struct smb_version_operations smb20_operations;
extern struct smb_version_values smb20_values;
#endif /* CIFS_ALLOW_INSECURE_LEGACY */
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index f99cc6f0c5d9c..eacf4c78543cc 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -25,6 +25,7 @@
#ifdef CONFIG_CIFS_DFS_UPCALL
#include "dfs_cache.h"
#endif
+#include "smb1proto.h"
struct statfs;
struct smb_vol;
@@ -373,16 +374,6 @@ extern int CIFSSMBSetFileSize(const unsigned int xid, struct cifs_tcon *tcon,
struct cifsFileInfo *cfile, __u64 size,
bool set_allocation);
-struct cifs_unix_set_info_args {
- __u64 ctime;
- __u64 atime;
- __u64 mtime;
- __u64 mode;
- kuid_t uid;
- kgid_t gid;
- dev_t device;
-};
-
extern int CIFSSMBUnixSetFileInfo(const unsigned int xid,
struct cifs_tcon *tcon,
const struct cifs_unix_set_info_args *args,
diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
index ad6c2fed4055b..e6a4257f925e1 100644
--- a/fs/cifs/fs_context.c
+++ b/fs/cifs/fs_context.c
@@ -9,6 +9,7 @@
#include "cifsglob.h"
#include "cifs_debug.h"
#include "fs_context.h"
+#include "smb1proto.h"
static const match_table_t cifs_smb_version_tokens = {
{ Smb_1, SMB1_VERSION_STRING },
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index f4247e9536a9d..bbde5559d6751 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -227,146 +227,6 @@ cifs_get_next_mid(struct TCP_Server_Info *server)
return mid;
}
-/*
- return codes:
- 0 not a transact2, or all data present
- >0 transact2 with that much data missing
- -EINVAL invalid transact2
- */
-static int
-check2ndT2(char *buf)
-{
- struct smb_hdr *pSMB = (struct smb_hdr *)buf;
- struct smb_t2_rsp *pSMBt;
- int remaining;
- __u16 total_data_size, data_in_this_rsp;
-
- if (pSMB->Command != SMB_COM_TRANSACTION2)
- return 0;
-
- /* check for plausible wct, bcc and t2 data and parm sizes */
- /* check for parm and data offset going beyond end of smb */
- if (pSMB->WordCount != 10) { /* coalesce_t2 depends on this */
- cifs_dbg(FYI, "Invalid transact2 word count\n");
- return -EINVAL;
- }
-
- pSMBt = (struct smb_t2_rsp *)pSMB;
-
- total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
- data_in_this_rsp = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
-
- if (total_data_size == data_in_this_rsp)
- return 0;
- else if (total_data_size < data_in_this_rsp) {
- cifs_dbg(FYI, "total data %d smaller than data in frame %d\n",
- total_data_size, data_in_this_rsp);
- return -EINVAL;
- }
-
- remaining = total_data_size - data_in_this_rsp;
-
- cifs_dbg(FYI, "missing %d bytes from transact2, check next response\n",
- remaining);
- if (total_data_size > CIFSMaxBufSize) {
- cifs_dbg(VFS, "TotalDataSize %d is over maximum buffer %d\n",
- total_data_size, CIFSMaxBufSize);
- return -EINVAL;
- }
- return remaining;
-}
-
-static int
-coalesce_t2(char *second_buf, struct smb_hdr *target_hdr)
-{
- struct smb_t2_rsp *pSMBs = (struct smb_t2_rsp *)second_buf;
- struct smb_t2_rsp *pSMBt = (struct smb_t2_rsp *)target_hdr;
- char *data_area_of_tgt;
- char *data_area_of_src;
- int remaining;
- unsigned int byte_count, total_in_tgt;
- __u16 tgt_total_cnt, src_total_cnt, total_in_src;
-
- src_total_cnt = get_unaligned_le16(&pSMBs->t2_rsp.TotalDataCount);
- tgt_total_cnt = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
-
- if (tgt_total_cnt != src_total_cnt)
- cifs_dbg(FYI, "total data count of primary and secondary t2 differ source=%hu target=%hu\n",
- src_total_cnt, tgt_total_cnt);
-
- total_in_tgt = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
-
- remaining = tgt_total_cnt - total_in_tgt;
-
- if (remaining < 0) {
- cifs_dbg(FYI, "Server sent too much data. tgt_total_cnt=%hu total_in_tgt=%u\n",
- tgt_total_cnt, total_in_tgt);
- return -EPROTO;
- }
-
- if (remaining == 0) {
- /* nothing to do, ignore */
- cifs_dbg(FYI, "no more data remains\n");
- return 0;
- }
-
- total_in_src = get_unaligned_le16(&pSMBs->t2_rsp.DataCount);
- if (remaining < total_in_src)
- cifs_dbg(FYI, "transact2 2nd response contains too much data\n");
-
- /* find end of first SMB data area */
- data_area_of_tgt = (char *)&pSMBt->hdr.Protocol +
- get_unaligned_le16(&pSMBt->t2_rsp.DataOffset);
-
- /* validate target area */
- data_area_of_src = (char *)&pSMBs->hdr.Protocol +
- get_unaligned_le16(&pSMBs->t2_rsp.DataOffset);
-
- data_area_of_tgt += total_in_tgt;
-
- total_in_tgt += total_in_src;
- /* is the result too big for the field? */
- if (total_in_tgt > USHRT_MAX) {
- cifs_dbg(FYI, "coalesced DataCount too large (%u)\n",
- total_in_tgt);
- return -EPROTO;
- }
- put_unaligned_le16(total_in_tgt, &pSMBt->t2_rsp.DataCount);
-
- /* fix up the BCC */
- byte_count = get_bcc(target_hdr);
- byte_count += total_in_src;
- /* is the result too big for the field? */
- if (byte_count > USHRT_MAX) {
- cifs_dbg(FYI, "coalesced BCC too large (%u)\n", byte_count);
- return -EPROTO;
- }
- put_bcc(byte_count, target_hdr);
-
- byte_count = be32_to_cpu(target_hdr->smb_buf_length);
- byte_count += total_in_src;
- /* don't allow buffer to overflow */
- if (byte_count > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
- cifs_dbg(FYI, "coalesced BCC exceeds buffer size (%u)\n",
- byte_count);
- return -ENOBUFS;
- }
- target_hdr->smb_buf_length = cpu_to_be32(byte_count);
-
- /* copy second buffer into end of first buffer */
- memcpy(data_area_of_tgt, data_area_of_src, total_in_src);
-
- if (remaining != total_in_src) {
- /* more responses to go */
- cifs_dbg(FYI, "waiting for more secondary responses\n");
- return 1;
- }
-
- /* we are done */
- cifs_dbg(FYI, "found the last secondary response\n");
- return 0;
-}
-
static void
cifs_downgrade_oplock(struct TCP_Server_Info *server,
struct cifsInodeInfo *cinode, __u32 oplock,
@@ -375,37 +235,6 @@ cifs_downgrade_oplock(struct TCP_Server_Info *server,
cifs_set_oplock_level(cinode, oplock);
}
-static bool
-cifs_check_trans2(struct mid_q_entry *mid, struct TCP_Server_Info *server,
- char *buf, int malformed)
-{
- if (malformed)
- return false;
- if (check2ndT2(buf) <= 0)
- return false;
- mid->multiRsp = true;
- if (mid->resp_buf) {
- /* merge response - fix up 1st*/
- malformed = coalesce_t2(buf, mid->resp_buf);
- if (malformed > 0)
- return true;
- /* All parts received or packet is malformed. */
- mid->multiEnd = true;
- dequeue_mid(server, mid, malformed);
- return true;
- }
- if (!server->large_buf) {
- /*FIXME: switch to already allocated largebuf?*/
- cifs_dbg(VFS, "1st trans2 resp needs bigbuf\n");
- } else {
- /* Have first buffer */
- mid->resp_buf = buf;
- mid->large_buf = true;
- server->bigbuf = NULL;
- }
- return true;
-}
-
static bool
cifs_need_neg(struct TCP_Server_Info *server)
{
diff --git a/fs/cifs/smb1proto.h b/fs/cifs/smb1proto.h
new file mode 100644
index 0000000000000..6a8fa2931008b
--- /dev/null
+++ b/fs/cifs/smb1proto.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
+/*
+ *
+ * Copyright (c) International Business Machines Corp., 2002,2008
+ * Author(s): Steve French (sfrench@xxxxxxxxxx)
+ *
+ */
+#ifndef _SMB1PROTO_H
+#define _SMB1PROTO_H
+
+struct cifs_unix_set_info_args {
+ __u64 ctime;
+ __u64 atime;
+ __u64 mtime;
+ __u64 mode;
+ kuid_t uid;
+ kgid_t gid;
+ dev_t device;
+};
+
+/*
+ * smb1transport.c
+ */
+bool cifs_check_trans2(struct mid_q_entry *mid, struct TCP_Server_Info *server,
+ char *buf, int malformed);
+
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+
+/*
+ * cifssmb.c
+ */
+
+/*
+ * smb1ops.c
+ */
+extern struct smb_version_operations smb1_operations;
+extern struct smb_version_values smb1_values;
+
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
+#endif /* _SMB1PROTO_H */
diff --git a/fs/cifs/smb1transport.c b/fs/cifs/smb1transport.c
new file mode 100644
index 0000000000000..41b62c429b845
--- /dev/null
+++ b/fs/cifs/smb1transport.c
@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "../smb/client/smb1transport.c"
diff --git a/fs/smb/client/smb1transport.c b/fs/smb/client/smb1transport.c
new file mode 100644
index 0000000000000..f2b19d7786f42
--- /dev/null
+++ b/fs/smb/client/smb1transport.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SMB1 transport receive helpers
+ */
+
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_debug.h"
+#include "cifspdu.h"
+
+/*
+ return codes:
+ 0 not a transact2, or all data present
+ >0 transact2 with that much data missing
+ -EINVAL invalid transact2
+ */
+static int
+check2ndT2(char *buf)
+{
+ struct smb_hdr *pSMB = (struct smb_hdr *)buf;
+ struct smb_t2_rsp *pSMBt;
+ int remaining;
+ __u16 total_data_size, data_in_this_rsp;
+
+ if (pSMB->Command != SMB_COM_TRANSACTION2)
+ return 0;
+
+ /* check for plausible wct, bcc and t2 data and parm sizes */
+ /* check for parm and data offset going beyond end of smb */
+ if (pSMB->WordCount != 10) { /* coalesce_t2 depends on this */
+ cifs_dbg(FYI, "Invalid transact2 word count\n");
+ return -EINVAL;
+ }
+
+ pSMBt = (struct smb_t2_rsp *)pSMB;
+
+ total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
+ data_in_this_rsp = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
+
+ if (total_data_size == data_in_this_rsp)
+ return 0;
+ else if (total_data_size < data_in_this_rsp) {
+ cifs_dbg(FYI, "total data %d smaller than data in frame %d\n",
+ total_data_size, data_in_this_rsp);
+ return -EINVAL;
+ }
+
+ remaining = total_data_size - data_in_this_rsp;
+
+ cifs_dbg(FYI, "missing %d bytes from transact2, check next response\n",
+ remaining);
+ if (total_data_size > CIFSMaxBufSize) {
+ cifs_dbg(VFS, "TotalDataSize %d is over maximum buffer %d\n",
+ total_data_size, CIFSMaxBufSize);
+ return -EINVAL;
+ }
+ return remaining;
+}
+
+static int
+coalesce_t2(char *second_buf, struct smb_hdr *target_hdr)
+{
+ struct smb_t2_rsp *pSMBs = (struct smb_t2_rsp *)second_buf;
+ struct smb_t2_rsp *pSMBt = (struct smb_t2_rsp *)target_hdr;
+ char *data_area_of_tgt;
+ char *data_area_of_src;
+ int remaining;
+ unsigned int byte_count, total_in_tgt;
+ __u16 tgt_total_cnt, src_total_cnt, total_in_src;
+
+ src_total_cnt = get_unaligned_le16(&pSMBs->t2_rsp.TotalDataCount);
+ tgt_total_cnt = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
+
+ if (tgt_total_cnt != src_total_cnt)
+ cifs_dbg(FYI, "total data count of primary and secondary t2 differ source=%hu target=%hu\n",
+ src_total_cnt, tgt_total_cnt);
+
+ total_in_tgt = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
+
+ remaining = tgt_total_cnt - total_in_tgt;
+
+ if (remaining < 0) {
+ cifs_dbg(FYI, "Server sent too much data. tgt_total_cnt=%hu total_in_tgt=%u\n",
+ tgt_total_cnt, total_in_tgt);
+ return -EPROTO;
+ }
+
+ if (remaining == 0) {
+ /* nothing to do, ignore */
+ cifs_dbg(FYI, "no more data remains\n");
+ return 0;
+ }
+
+ total_in_src = get_unaligned_le16(&pSMBs->t2_rsp.DataCount);
+ if (remaining < total_in_src)
+ cifs_dbg(FYI, "transact2 2nd response contains too much data\n");
+
+ /* find end of first SMB data area */
+ data_area_of_tgt = (char *)&pSMBt->hdr.Protocol +
+ get_unaligned_le16(&pSMBt->t2_rsp.DataOffset);
+
+ /* validate target area */
+ data_area_of_src = (char *)&pSMBs->hdr.Protocol +
+ get_unaligned_le16(&pSMBs->t2_rsp.DataOffset);
+
+ data_area_of_tgt += total_in_tgt;
+
+ total_in_tgt += total_in_src;
+ /* is the result too big for the field? */
+ if (total_in_tgt > USHRT_MAX) {
+ cifs_dbg(FYI, "coalesced DataCount too large (%u)\n",
+ total_in_tgt);
+ return -EPROTO;
+ }
+ put_unaligned_le16(total_in_tgt, &pSMBt->t2_rsp.DataCount);
+
+ /* fix up the BCC */
+ byte_count = get_bcc(target_hdr);
+ byte_count += total_in_src;
+ /* is the result too big for the field? */
+ if (byte_count > USHRT_MAX) {
+ cifs_dbg(FYI, "coalesced BCC too large (%u)\n", byte_count);
+ return -EPROTO;
+ }
+ put_bcc(byte_count, target_hdr);
+
+ byte_count = be32_to_cpu(target_hdr->smb_buf_length);
+ byte_count += total_in_src;
+ /* don't allow buffer to overflow */
+ if (byte_count > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
+ cifs_dbg(FYI, "coalesced BCC exceeds buffer size (%u)\n",
+ byte_count);
+ return -ENOBUFS;
+ }
+ target_hdr->smb_buf_length = cpu_to_be32(byte_count);
+
+ /* copy second buffer into end of first buffer */
+ memcpy(data_area_of_tgt, data_area_of_src, total_in_src);
+
+ if (remaining != total_in_src) {
+ /* more responses to go */
+ cifs_dbg(FYI, "waiting for more secondary responses\n");
+ return 1;
+ }
+
+ /* we are done */
+ cifs_dbg(FYI, "found the last secondary response\n");
+ return 0;
+}
+
+bool
+cifs_check_trans2(struct mid_q_entry *mid, struct TCP_Server_Info *server,
+ char *buf, int malformed)
+{
+ if (malformed)
+ return false;
+ if (check2ndT2(buf) <= 0)
+ return false;
+ mid->multiRsp = true;
+ if (mid->resp_buf) {
+ /* merge response - fix up 1st*/
+ malformed = coalesce_t2(buf, mid->resp_buf);
+ if (malformed > 0)
+ return true;
+ /* All parts received or packet is malformed. */
+ mid->multiEnd = true;
+ dequeue_mid(server, mid, malformed);
+ return true;
+ }
+ if (!server->large_buf) {
+ /*FIXME: switch to already allocated largebuf?*/
+ cifs_dbg(VFS, "1st trans2 resp needs bigbuf\n");
+ } else {
+ /* Have first buffer */
+ mid->resp_buf = buf;
+ mid->large_buf = true;
+ server->bigbuf = NULL;
+ }
+ return true;
+}
--
2.53.0