smb3: Replace smb2pdu 1-element arrays with flex-arrays
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 <[email protected]>
Cc: Paulo Alcantara <[email protected]>
Cc: Ronnie Sahlberg <[email protected]>
Cc: Shyam Prasad N <[email protected]>
Cc: Tom Talpey <[email protected]>
Cc: Namjae Jeon <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: [email protected]
Cc: [email protected]
BUG=b/330618063
TEST=presubmit
RELEASE_NOTE=Fixed a crash during CIFS volumes mount.
Reviewed-by: Namjae Jeon <[email protected]>
cos-patch: bug
Change-Id: I4f3b4c677640ee81002fe3dffe37daaab8659349
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: Steve French <[email protected]>
Signed-off-by: Vasiliy Kovalev <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/69373
Tested-by: Cusky Presubmit Bot <[email protected]>
Reviewed-by: Oleksandr Tymoshenko <[email protected]>
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index e2f401c..8f40940 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -113,7 +113,7 @@
} 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/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index bad09d7..38a7481 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -5828,7 +5828,7 @@
.header_size = sizeof(struct smb2_sync_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,
@@ -5850,7 +5850,7 @@
.header_size = sizeof(struct smb2_sync_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,
@@ -5871,7 +5871,7 @@
.header_size = sizeof(struct smb2_sync_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,
@@ -5892,7 +5892,7 @@
.header_size = sizeof(struct smb2_sync_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,
@@ -5913,7 +5913,7 @@
.header_size = sizeof(struct smb2_sync_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,
@@ -5934,7 +5934,7 @@
.header_size = sizeof(struct smb2_sync_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,
@@ -5955,7 +5955,7 @@
.header_size = sizeof(struct smb2_sync_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/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 541f7d6..18c639a 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1327,7 +1327,7 @@
/* 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));
@@ -1826,8 +1826,7 @@
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;
@@ -4767,7 +4766,7 @@
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
@@ -4964,7 +4963,7 @@
req->AdditionalInformation = cpu_to_le32(additional_info);
req->BufferOffset =
- cpu_to_le16(sizeof(struct smb2_set_info_req) - 1);
+ cpu_to_le16(sizeof(struct smb2_set_info_req));
req->BufferLength = cpu_to_le32(*size);
memcpy(req->Buffer, *data, *size);
@@ -5196,9 +5195,9 @@
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/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 301c155..812a1b5 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -218,7 +218,7 @@
__le16 StructureSize;
__le16 Reserved; /* MBZ */
__le32 ByteCount; /* even if zero, at least one byte follows */
- __u8 ErrorData[1]; /* variable length */
+ __u8 ErrorData[]; /* variable length */
} __packed;
#define SYMLINK_ERROR_TAG 0x4c4d5953
@@ -487,7 +487,7 @@
__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;
/* Flags */
@@ -504,7 +504,7 @@
__le16 SecurityBufferOffset;
__le16 SecurityBufferLength;
__u64 PreviousSessionId;
- __u8 Buffer[1]; /* variable length GSS security buffer */
+ __u8 Buffer[]; /* variable length GSS security buffer */
} __packed;
/* Currently defined SessionFlags */
@@ -517,7 +517,7 @@
__le16 SessionFlags;
__le16 SecurityBufferOffset;
__le16 SecurityBufferLength;
- __u8 Buffer[1]; /* variable length GSS security buffer */
+ __u8 Buffer[]; /* variable length GSS security buffer */
} __packed;
struct smb2_logoff_req {
@@ -543,7 +543,7 @@
__le16 Flags; /* Reserved MBZ for dialects prior to SMB3.1.1 */
__le16 PathOffset;
__le16 PathLength;
- __u8 Buffer[1]; /* variable length */
+ __u8 Buffer[]; /* variable length */
} __packed;
/* See MS-SMB2 section 2.2.9.2 */
@@ -852,7 +852,7 @@
__u64 VolatileFileId; /* opaque endianness */
__le32 CreateContextsOffset;
__le32 CreateContextsLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct create_context {
@@ -1313,7 +1313,7 @@
__le32 RemainingBytes;
__le16 ReadChannelInfoOffset;
__le16 ReadChannelInfoLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/* Read flags */
@@ -1328,7 +1328,7 @@
__le32 DataLength;
__le32 DataRemaining;
__u32 Flags;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/* For write request Flags field below the following flags are defined: */
@@ -1348,7 +1348,7 @@
__le16 WriteChannelInfoOffset;
__le16 WriteChannelInfoLength;
__le32 Flags;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_write_rsp {
@@ -1359,7 +1359,7 @@
__le32 DataLength;
__le32 DataRemaining;
__u32 Reserved2;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/* notify flags */
@@ -1395,7 +1395,7 @@
__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;
#define SMB2_LOCKFLAG_SHARED_LOCK 0x0001
@@ -1422,7 +1422,10 @@
__u64 PersistentFileId; /* opaque endianness */
__u64 VolatileFileId; /* opaque endianness */
/* 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 {
@@ -1478,7 +1481,7 @@
__le16 FileNameOffset;
__le16 FileNameLength;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_query_directory_rsp {
@@ -1486,7 +1489,7 @@
__le16 StructureSize; /* Must be 9 */
__le16 OutputBufferOffset;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/* Possible InfoType values */
@@ -1527,7 +1530,7 @@
__le32 Flags;
__u64 PersistentFileId; /* opaque endianness */
__u64 VolatileFileId; /* opaque endianness */
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_query_info_rsp {
@@ -1535,7 +1538,7 @@
__le16 StructureSize; /* Must be 9 */
__le16 OutputBufferOffset;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
/*
@@ -1558,7 +1561,7 @@
__le32 AdditionalInformation;
__u64 PersistentFileId; /* opaque endianness */
__u64 VolatileFileId; /* opaque endianness */
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
struct smb2_set_info_rsp {
@@ -1761,7 +1764,10 @@
__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 */
