| Message ID | 1610615171-68296-1-git-send-email-abaci-bugfix@linux.alibaba.com |
|---|---|
| State | New |
| Headers | show |
| Series | fs/cifs: Replace one-element array with flexible-array member. | expand |
Hi Jiapeng, This will change the size returned by sizeof(). Have you checked that this doesn't introduce off-by-one errors in all the sizeof() usage? Cheers,
Jiapeng,
Aurelien is correct, you should respin this patch and correct for
where it breaks the sizeof calculation. For example your change:
struct smb2_lock_rsp {
@@ -1434,7 +1434,7 @@ struct smb2_query_directory_req {
__le16 FileNameOffset;
__le16 FileNameLength;
__le32 OutputBufferLength;
- __u8 Buffer[1];
+ __u8 Buffer[];
} __packed;
would have the side effect of making the file name off by one:
smb2pdu.c-4654- req->FileNameOffset =
smb2pdu.c:4655: cpu_to_le16(sizeof(struct
smb2_query_directory_req) - 1);
On Thu, Jan 14, 2021 at 3:26 AM Aurélien Aptel via samba-technical
<samba-technical@lists.samba.org> wrote:
>
> Hi Jiapeng,
>
> This will change the size returned by sizeof(). Have you checked that
> this doesn't introduce off-by-one errors in all the sizeof() usage?
>
> Cheers,
> --
> Aurélien Aptel / SUSE Labs Samba Team
> GPG: 1839 CB5F 9F5B FB9B AA97 8C99 03C8 A49B 521B D5D3
> SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg, DE
> GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 247165 (AG München)
>
>
On Sun, Jan 17, 2021 at 03:58:23PM -0600, Steve French wrote: > Jiapeng, > Aurelien is correct, you should respin this patch and correct for > where it breaks the sizeof calculation. For example your change: > > struct smb2_lock_rsp { > @@ -1434,7 +1434,7 @@ struct smb2_query_directory_req { > __le16 FileNameOffset; > __le16 FileNameLength; > __le32 OutputBufferLength; > - __u8 Buffer[1]; > + __u8 Buffer[]; > } __packed; > > would have the side effect of making the file name off by one: > > smb2pdu.c-4654- req->FileNameOffset = > smb2pdu.c:4655: cpu_to_le16(sizeof(struct > smb2_query_directory_req) - 1); FWIW, that sizeof() - 1 should've been offsetof()...
On Sun, Jan 17, 2021 at 6:02 PM Al Viro <viro@zeniv.linux.org.uk> wrote: > > On Sun, Jan 17, 2021 at 03:58:23PM -0600, Steve French wrote: > > Jiapeng, > > Aurelien is correct, you should respin this patch and correct for > > where it breaks the sizeof calculation. For example your change: > > > > struct smb2_lock_rsp { > > @@ -1434,7 +1434,7 @@ struct smb2_query_directory_req { > > __le16 FileNameOffset; > > __le16 FileNameLength; > > __le32 OutputBufferLength; > > - __u8 Buffer[1]; > > + __u8 Buffer[]; > > } __packed; > > > > would have the side effect of making the file name off by one: > > > > smb2pdu.c-4654- req->FileNameOffset = > > smb2pdu.c:4655: cpu_to_le16(sizeof(struct > > smb2_query_directory_req) - 1); > > FWIW, that sizeof() - 1 should've been offsetof()... agreed
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 204a622..7c9ac5d 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -1289,7 +1289,7 @@ struct smb2_read_plain_req { __le32 RemainingBytes; __le16 ReadChannelInfoOffset; __le16 ReadChannelInfoLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* Read flags */ @@ -1304,7 +1304,7 @@ struct smb2_read_rsp { __le32 DataLength; __le32 DataRemaining; __u32 Flags; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* For write request Flags field below the following flags are defined: */ @@ -1324,7 +1324,7 @@ struct smb2_write_req { __le16 WriteChannelInfoOffset; __le16 WriteChannelInfoLength; __le32 Flags; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_write_rsp { @@ -1335,7 +1335,7 @@ struct smb2_write_rsp { __le32 DataLength; __le32 DataRemaining; __u32 Reserved2; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* notify flags */ @@ -1371,7 +1371,7 @@ 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; #define SMB2_LOCKFLAG_SHARED_LOCK 0x0001 @@ -1394,7 +1394,7 @@ struct smb2_lock_req { __u64 PersistentFileId; /* opaque endianness */ __u64 VolatileFileId; /* opaque endianness */ /* Followed by at least one */ - struct smb2_lock_element locks[1]; + struct smb2_lock_element locks[]; } __packed; struct smb2_lock_rsp { @@ -1434,7 +1434,7 @@ struct smb2_query_directory_req { __le16 FileNameOffset; __le16 FileNameLength; __le32 OutputBufferLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_query_directory_rsp { @@ -1442,7 +1442,7 @@ struct smb2_query_directory_rsp { __le16 StructureSize; /* Must be 9 */ __le16 OutputBufferOffset; __le32 OutputBufferLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* Possible InfoType values */ @@ -1483,7 +1483,7 @@ struct smb2_query_info_req { __le32 Flags; __u64 PersistentFileId; /* opaque endianness */ __u64 VolatileFileId; /* opaque endianness */ - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_query_info_rsp { @@ -1491,7 +1491,7 @@ struct smb2_query_info_rsp { __le16 StructureSize; /* Must be 9 */ __le16 OutputBufferOffset; __le32 OutputBufferLength; - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; /* @@ -1514,7 +1514,7 @@ struct smb2_set_info_req { __le32 AdditionalInformation; __u64 PersistentFileId; /* opaque endianness */ __u64 VolatileFileId; /* opaque endianness */ - __u8 Buffer[1]; + __u8 Buffer[]; } __packed; struct smb2_set_info_rsp { @@ -1716,7 +1716,7 @@ struct smb2_file_all_info { /* data block encoding of response to level 18 */ __le32 Mode; __le32 AlignmentRequirement; __le32 FileNameLength; - char FileName[1]; + char FileName[]; } __packed; /* level 18 Query */ struct smb2_file_eof_info { /* encoding of request for level 10 */
Fix the following coccicheck warning: ./fs/cifs/smb2pdu.h:1711:8-16: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/ process/deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1509:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/ process/deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1486:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/ process/deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1478:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/ process/deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1437:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1429:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/ process/deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1389:26-31: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1389:26-31: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1366:6-12: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1330:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1319:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1299:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) ./fs/cifs/smb2pdu.h:1284:8-14: WARNING use flexible-array member instead(https://www.kernel.org/doc/html/latest/process /deprecated.html#zero-length-and-one-element-arrays) Reported-by: Abaci Robot<abaci@linux.alibaba.com> Signed-off-by: Jiapeng Zhong <abaci-bugfix@linux.alibaba.com> --- fs/cifs/smb2pdu.h | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-)