From: Kees Cook <keescook@xxxxxxxxxxxx>
commit eb3e28c1e89b4984308777231887e41aa8a0151f upstream.
The kernel is globally removing the ambiguous 0-length and 1-element
arrays in favor of flexible arrays, so that we can gain both compile-time
and run-time array bounds checking[1].
Replace the trailing 1-element array with a flexible array in the
following structures:
struct smb2_err_rsp
struct smb2_tree_connect_req
struct smb2_negotiate_rsp
struct smb2_sess_setup_req
struct smb2_sess_setup_rsp
struct smb2_read_req
struct smb2_read_rsp
struct smb2_write_req
struct smb2_write_rsp
struct smb2_query_directory_req
struct smb2_query_directory_rsp
struct smb2_set_info_req
struct smb2_change_notify_rsp
struct smb2_create_rsp
struct smb2_query_info_req
struct smb2_query_info_rsp
Replace the trailing 1-element array with a flexible array, but leave
the existing structure padding:
struct smb2_file_all_info
struct smb2_lock_req
Adjust all related size calculations to match the changes to sizeof().
No machine code output or .data section differences are produced after
these changes.
[1] For lots of details, see both:
https://docs.kernel.org/process/deprecated.html#zero-length-and-one-element-arrays
https://people.kernel.org/kees/bounded-flexible-arrays-in-c
Cc: Steve French <sfrench@xxxxxxxxx>
Cc: Paulo Alcantara <pc@xxxxxx>
Cc: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Cc: Shyam Prasad N <sprasad@xxxxxxxxxxxxx>
Cc: Tom Talpey <tom@xxxxxxxxxx>
Cc: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: linux-cifs@xxxxxxxxxxxxxxx
Cc: samba-technical@xxxxxxxxxxxxxxx
Reviewed-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
---
fs/smb/client/smb2file.c | 2 +-
fs/smb/client/smb2misc.c | 2 +-
fs/smb/client/smb2ops.c | 14 +++++++-------
fs/smb/client/smb2pdu.c | 16 +++++++--------
fs/smb/client/smb2pdu.h | 2 +-
fs/smb/common/smb2pdu.h | 42 +++++++++++++++++++++++-----------------
fs/smb/server/smb2ops.c | 8 ++++----
fs/smb/server/smb2pdu.c | 8 +++-----
8 files changed, 48 insertions(+), 46 deletions(-)
diff --git a/fs/smb/client/smb2file.c b/fs/smb/client/smb2file.c
index ba6cc50af390..a7475bc05cac 100644
--- a/fs/smb/client/smb2file.c
+++ b/fs/smb/client/smb2file.c
@@ -34,7 +34,7 @@ static struct smb2_symlink_err_rsp
*symlink_data(const struct kvec *iov)
len = (u32)err->ErrorContextCount * (offsetof(struct smb2_error_context_rsp,
ErrorContextData) +
sizeof(struct smb2_symlink_err_rsp));
- if (le32_to_cpu(err->ByteCount) < len || iov->iov_len < len + sizeof(*err))
+ if (le32_to_cpu(err->ByteCount) < len || iov->iov_len < len +
sizeof(*err) + 1)
return ERR_PTR(-EINVAL);
p = (struct smb2_error_context_rsp *)err->ErrorData;
diff --git a/fs/smb/client/smb2misc.c b/fs/smb/client/smb2misc.c
index 88942b1fb431..fdf7a7f188c5 100644
--- a/fs/smb/client/smb2misc.c
+++ b/fs/smb/client/smb2misc.c
@@ -113,7 +113,7 @@ static __u32 get_neg_ctxt_len(struct smb2_hdr
*hdr, __u32 len,
} else if (nc_offset + 1 == non_ctxlen) {
cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
size_of_pad_before_neg_ctxts = 0;
- } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE)
+ } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
/* has padding, but no SPNEGO blob */
size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
else
diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 285d360eb59a..4596d2dfdec3 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -5764,7 +5764,7 @@ struct smb_version_values smb20_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -5786,7 +5786,7 @@ struct smb_version_values smb21_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -5807,7 +5807,7 @@ struct smb_version_values smb3any_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -5828,7 +5828,7 @@ struct smb_version_values smbdefault_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -5849,7 +5849,7 @@ struct smb_version_values smb30_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -5870,7 +5870,7 @@ struct smb_version_values smb302_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -5891,7 +5891,7 @@ struct smb_version_values smb311_values = {
.header_size = sizeof(struct smb2_hdr),
.header_preamble_size = 0,
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
index 05ff8a457a3d..2dfbf1b23cfa 100644
--- a/fs/smb/client/smb2pdu.c
+++ b/fs/smb/client/smb2pdu.c
@@ -1386,7 +1386,7 @@ SMB2_sess_sendreceive(struct SMB2_sess_data *sess_data)
/* Testing shows that buffer offset must be at location of Buffer[0] */
req->SecurityBufferOffset =
- cpu_to_le16(sizeof(struct smb2_sess_setup_req) - 1 /* pad */);
+ cpu_to_le16(sizeof(struct smb2_sess_setup_req));
req->SecurityBufferLength = cpu_to_le16(sess_data->iov[1].iov_len);
memset(&rqst, 0, sizeof(struct smb_rqst));
@@ -1905,8 +1905,7 @@ SMB2_tcon(const unsigned int xid, struct
cifs_ses *ses, const char *tree,
iov[0].iov_len = total_len - 1;
/* Testing shows that buffer offset must be at location of Buffer[0] */
- req->PathOffset = cpu_to_le16(sizeof(struct smb2_tree_connect_req)
- - 1 /* pad */);
+ req->PathOffset = cpu_to_le16(sizeof(struct smb2_tree_connect_req));
req->PathLength = cpu_to_le16(unc_path_len - 2);
iov[1].iov_base = unc_path;
iov[1].iov_len = unc_path_len;
@@ -3796,7 +3795,7 @@ SMB2_change_notify(const unsigned int xid,
struct cifs_tcon *tcon,
ses->Suid, (u8)watch_tree, completion_filter);
/* validate that notify information is plausible */
if ((rsp_iov.iov_base == NULL) ||
- (rsp_iov.iov_len < sizeof(struct smb2_change_notify_rsp)))
+ (rsp_iov.iov_len < sizeof(struct smb2_change_notify_rsp) + 1))
goto cnotify_exit;
smb_rsp = (struct smb2_change_notify_rsp *)rsp_iov.iov_base;
@@ -5009,7 +5008,7 @@ int SMB2_query_directory_init(const unsigned int xid,
memcpy(bufptr, &asteriks, len);
req->FileNameOffset =
- cpu_to_le16(sizeof(struct smb2_query_directory_req) - 1);
+ cpu_to_le16(sizeof(struct smb2_query_directory_req));
req->FileNameLength = cpu_to_le16(len);
/*
* BB could be 30 bytes or so longer if we used SMB2 specific
@@ -5205,8 +5204,7 @@ SMB2_set_info_init(struct cifs_tcon *tcon,
struct TCP_Server_Info *server,
req->VolatileFileId = volatile_fid;
req->AdditionalInformation = cpu_to_le32(additional_info);
- req->BufferOffset =
- cpu_to_le16(sizeof(struct smb2_set_info_req) - 1);
+ req->BufferOffset = cpu_to_le16(sizeof(struct smb2_set_info_req));
req->BufferLength = cpu_to_le32(*size);
memcpy(req->Buffer, *data, *size);
@@ -5440,9 +5438,9 @@ build_qfs_info_req(struct kvec *iov, struct
cifs_tcon *tcon,
req->VolatileFileId = volatile_fid;
/* 1 for pad */
req->InputBufferOffset =
- cpu_to_le16(sizeof(struct smb2_query_info_req) - 1);
+ cpu_to_le16(sizeof(struct smb2_query_info_req));
req->OutputBufferLength = cpu_to_le32(
- outbuf_len + sizeof(struct smb2_query_info_rsp) - 1);
+ outbuf_len + sizeof(struct smb2_query_info_rsp));
iov->iov_base = (char *)req;
iov->iov_len = total_len;
diff --git a/fs/smb/client/smb2pdu.h b/fs/smb/client/smb2pdu.h
index 1237bb86e93a..a5773a06aba8 100644
--- a/fs/smb/client/smb2pdu.h
+++ b/fs/smb/client/smb2pdu.h
@@ -57,7 +57,7 @@ struct smb2_rdma_crypto_transform {
#define COMPOUND_FID 0xFFFFFFFFFFFFFFFFULL
#define SMB2_SYMLINK_STRUCT_SIZE \
- (sizeof(struct smb2_err_rsp) - 1 + sizeof(struct smb2_symlink_err_rsp))
+ (sizeof(struct smb2_err_rsp) + sizeof(struct smb2_symlink_err_rsp))
#define SYMLINK_ERROR_TAG 0x4c4d5953
diff --git a/fs/smb/common/smb2pdu.h b/fs/smb/common/smb2pdu.h
index 07549957b309..5593bb49954c 100644
--- a/fs/smb/common/smb2pdu.h
+++ b/fs/smb/common/smb2pdu.h
@@ -189,7 +189,7 @@ struct smb2_err_rsp {
__u8 ErrorContextCount;
__u8 Reserved;
__le32 ByteCount; /* even if zero, at least one byte follows */
- __u8 ErrorData[1]; /* variable length */
+ __u8 ErrorData[]; /* variable length */
} __packed;
#define SMB3_AES_CCM_NONCE 11
@@ -330,7 +330,7 @@ struct smb2_tree_connect_req {
__le16 Flags; /* Flags in SMB3.1.1 */
__le16 PathOffset;
__le16 PathLength;
- __u8 Buffer[1]; /* variable length */
+ __u8 Buffer[]; /* variable length */
} __packed;
/* Possible ShareType values */
@@ -617,7 +617,7 @@ struct smb2_negotiate_rsp {
__le16 SecurityBufferOffset;
__le16 SecurityBufferLength;
__le32 NegotiateContextOffset; /* Pre:SMB3.1.1 was reserved/ignored */
- __u8 Buffer[1]; /* variable length GSS security buffer */
+ __u8 Buffer[]; /* variable length GSS security buffer */
} __packed;
@@ -638,7 +638,7 @@ struct smb2_sess_setup_req {
__le16 SecurityBufferOffset;
__le16 SecurityBufferLength;
__le64 PreviousSessionId;
- __u8 Buffer[1]; /* variable length GSS security buffer */
+ __u8 Buffer[]; /* variable length GSS security buffer */
} __packed;
/* Currently defined SessionFlags */
@@ -655,7 +655,7 @@ struct smb2_sess_setup_rsp {
__le16 SessionFlags;
__le16 SecurityBufferOffset;
__le16 SecurityBufferLength;
- __u8 Buffer[1]; /* variable length GSS security buffer */
+ __u8 Buffer[]; /* variable length GSS security buffer */
} __packed;
@@ -737,7 +737,7 @@ struct smb2_read_req {
__le32 RemainingBytes;
__le16 ReadChannelInfoOffset;
__le16 ReadChannelInfoLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/* Read flags */
@@ -752,7 +752,7 @@ struct smb2_read_rsp {
__le32 DataLength;
__le32 DataRemaining;
__le32 Flags;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
@@ -776,7 +776,7 @@ struct smb2_write_req {
__le16 WriteChannelInfoOffset;
__le16 WriteChannelInfoLength;
__le32 Flags;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_write_rsp {
@@ -787,7 +787,7 @@ struct smb2_write_rsp {
__le32 DataLength;
__le32 DataRemaining;
__u32 Reserved2;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
@@ -834,7 +834,10 @@ struct smb2_lock_req {
__u64 PersistentFileId;
__u64 VolatileFileId;
/* Followed by at least one */
- struct smb2_lock_element locks[1];
+ union {
+ struct smb2_lock_element lock;
+ DECLARE_FLEX_ARRAY(struct smb2_lock_element, locks);
+ };
} __packed;
struct smb2_lock_rsp {
@@ -888,7 +891,7 @@ struct smb2_query_directory_req {
__le16 FileNameOffset;
__le16 FileNameLength;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_query_directory_rsp {
@@ -896,7 +899,7 @@ struct smb2_query_directory_rsp {
__le16 StructureSize; /* Must be 9 */
__le16 OutputBufferOffset;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/*
@@ -919,7 +922,7 @@ struct smb2_set_info_req {
__le32 AdditionalInformation;
__u64 PersistentFileId;
__u64 VolatileFileId;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_set_info_rsp {
@@ -974,7 +977,7 @@ struct smb2_change_notify_rsp {
__le16 StructureSize; /* Must be 9 */
__le16 OutputBufferOffset;
__le32 OutputBufferLength;
- __u8 Buffer[1]; /* array of file notify structs */
+ __u8 Buffer[]; /* array of file notify structs */
} __packed;
@@ -1180,7 +1183,7 @@ struct smb2_create_rsp {
__u64 VolatileFileId;
__le32 CreateContextsOffset;
__le32 CreateContextsLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct create_posix {
@@ -1524,7 +1527,7 @@ struct smb2_query_info_req {
__le32 Flags;
__u64 PersistentFileId;
__u64 VolatileFileId;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_query_info_rsp {
@@ -1532,7 +1535,7 @@ struct smb2_query_info_rsp {
__le16 StructureSize; /* Must be 9 */
__le16 OutputBufferOffset;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/*
@@ -1593,7 +1596,10 @@ struct smb2_file_all_info { /* data block
encoding of response to level 18 */
__le32 Mode;
__le32 AlignmentRequirement;
__le32 FileNameLength;
- char FileName[1];
+ union {
+ char __pad; /* Legacy structure padding */
+ DECLARE_FLEX_ARRAY(char, FileName);
+ };
} __packed; /* level 18 Query */
struct smb2_file_eof_info { /* encoding of request for level 10 */
diff --git a/fs/smb/server/smb2ops.c b/fs/smb/server/smb2ops.c
index 535402629655..27a9dce3e03a 100644
--- a/fs/smb/server/smb2ops.c
+++ b/fs/smb/server/smb2ops.c
@@ -26,7 +26,7 @@ static struct smb_version_values smb21_server_values = {
.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
.header_size = sizeof(struct smb2_hdr),
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -52,7 +52,7 @@ static struct smb_version_values smb30_server_values = {
.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
.header_size = sizeof(struct smb2_hdr),
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -79,7 +79,7 @@ static struct smb_version_values smb302_server_values = {
.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
.header_size = sizeof(struct smb2_hdr),
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
@@ -106,7 +106,7 @@ static struct smb_version_values smb311_server_values = {
.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
.header_size = sizeof(struct smb2_hdr),
.max_header_size = MAX_SMB2_HDR_SIZE,
- .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+ .read_rsp_size = sizeof(struct smb2_read_rsp),
.lock_cmd = SMB2_LOCK,
.cap_unix = 0,
.cap_nt_find = SMB2_NT_FIND,
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index ea48dd06d4da..6e5ed0ac578a 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -294,8 +294,7 @@ int init_smb2_neg_rsp(struct ksmbd_work *work)
if (server_conf.signing == KSMBD_CONFIG_OPT_MANDATORY)
rsp->SecurityMode |= SMB2_NEGOTIATE_SIGNING_REQUIRED_LE;
err = ksmbd_iov_pin_rsp(work, rsp,
- sizeof(struct smb2_negotiate_rsp) -
- sizeof(rsp->Buffer) + AUTH_GSS_LENGTH);
+ sizeof(struct smb2_negotiate_rsp) + AUTH_GSS_LENGTH);
if (err)
return err;
conn->use_spnego = true;
@@ -1263,9 +1262,8 @@ int smb2_handle_negotiate(struct ksmbd_work *work)
if (!rc)
rc = ksmbd_iov_pin_rsp(work, rsp,
- sizeof(struct smb2_negotiate_rsp) -
- sizeof(rsp->Buffer) +
- AUTH_GSS_LENGTH + neg_ctxt_len);
+ sizeof(struct smb2_negotiate_rsp) +
+ AUTH_GSS_LENGTH + neg_ctxt_len);
if (rc < 0)
smb2_set_err_rsp(work);
return rc;
--
2.34.1
