diff mbox series

[5/7] ksmbd: add the check to vaildate if stream protocol length exceeds maximum value

Message ID 20210924021254.27096-6-linkinjeon@kernel.org
State New
Headers show
Series a bunch of patches that have not yet been reviewed | expand

Commit Message

Namjae Jeon Sept. 24, 2021, 2:12 a.m. UTC
This patch add MAX_STREAM_PROT_LEN macro and check if stream protocol
length exceeds maximum value. opencode pdu size check in
ksmbd_pdu_size_has_room().

Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
 fs/ksmbd/connection.c | 10 ++++++----
 fs/ksmbd/smb_common.c |  6 ------
 fs/ksmbd/smb_common.h |  4 ++--
 3 files changed, 8 insertions(+), 12 deletions(-)

Comments

Hyunchul Lee Sept. 25, 2021, 8:41 a.m. UTC | #1
2021년 9월 24일 (금) 오전 11:13, Namjae Jeon <linkinjeon@kernel.org>님이 작성:
>
> This patch add MAX_STREAM_PROT_LEN macro and check if stream protocol
> length exceeds maximum value. opencode pdu size check in
> ksmbd_pdu_size_has_room().
>
> Cc: Tom Talpey <tom@talpey.com>
> Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
> Cc: Ralph Böhme <slow@samba.org>
> Cc: Steve French <smfrench@gmail.com>
> Cc: Hyunchul Lee <hyc.lee@gmail.com>
> Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
> ---
>  fs/ksmbd/connection.c | 10 ++++++----
>  fs/ksmbd/smb_common.c |  6 ------
>  fs/ksmbd/smb_common.h |  4 ++--
>  3 files changed, 8 insertions(+), 12 deletions(-)
>
> diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c
> index af086d35398a..48b18b4ec117 100644
> --- a/fs/ksmbd/connection.c
> +++ b/fs/ksmbd/connection.c
> @@ -296,10 +296,12 @@ int ksmbd_conn_handler_loop(void *p)
>                 pdu_size = get_rfc1002_len(hdr_buf);
>                 ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size);
>
> -               /* make sure we have enough to get to SMB header end */
> -               if (!ksmbd_pdu_size_has_room(pdu_size)) {
> -                       ksmbd_debug(CONN, "SMB request too short (%u bytes)\n",
> -                                   pdu_size);
> +               /*
> +                * Check if pdu size is valid (min : smb header size,
> +                * max : 0x00FFFFFF).
> +                */
> +               if (pdu_size < __SMB2_HEADER_STRUCTURE_SIZE ||
> +                   pdu_size > MAX_STREAM_PROT_LEN) {
>                         continue;
>                 }
>
> diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c
> index 5901b2884c60..20bd5b8e3c0a 100644
> --- a/fs/ksmbd/smb_common.c
> +++ b/fs/ksmbd/smb_common.c
> @@ -21,7 +21,6 @@ static const char basechars[43] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%";
>  #define MAGIC_CHAR '~'
>  #define PERIOD '.'
>  #define mangle(V) ((char)(basechars[(V) % MANGLE_BASE]))
> -#define KSMBD_MIN_SUPPORTED_HEADER_SIZE        (sizeof(struct smb2_hdr))
>
>  struct smb_protocol {
>         int             index;
> @@ -272,11 +271,6 @@ int ksmbd_init_smb_server(struct ksmbd_work *work)
>         return 0;
>  }
>
> -bool ksmbd_pdu_size_has_room(unsigned int pdu)
> -{
> -       return (pdu >= KSMBD_MIN_SUPPORTED_HEADER_SIZE - 4);
> -}
> -
>  int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work, int info_level,
>                                       struct ksmbd_file *dir,
>                                       struct ksmbd_dir_info *d_info,
> diff --git a/fs/ksmbd/smb_common.h b/fs/ksmbd/smb_common.h
> index 994abede27e9..6e79e7577f6b 100644
> --- a/fs/ksmbd/smb_common.h
> +++ b/fs/ksmbd/smb_common.h
> @@ -48,6 +48,8 @@
>  #define CIFS_DEFAULT_IOSIZE    (64 * 1024)
>  #define MAX_CIFS_SMALL_BUFFER_SIZE 448 /* big enough for most */
>
> +#define MAX_STREAM_PROT_LEN    0x00FFFFFF

Do we need to append "SMB" to this macro name?
Looks good to me.
Acked-by: Hyunchul Lee <hyc.lee@gmail.com>


> +
>  /* Responses when opening a file. */
>  #define F_SUPERSEDED   0
>  #define F_OPENED       1
> @@ -493,8 +495,6 @@ int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count);
>
>  int ksmbd_init_smb_server(struct ksmbd_work *work);
>
> -bool ksmbd_pdu_size_has_room(unsigned int pdu);
> -
>  struct ksmbd_kstat;
>  int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work,
>                                       int info_level,
> --
> 2.25.1
>


--
Thanks,
Hyunchul
Namjae Jeon Sept. 25, 2021, 9:24 a.m. UTC | #2
2021-09-25 17:41 GMT+09:00, Hyunchul Lee <hyc.lee@gmail.com>:
> 2021년 9월 24일 (금) 오전 11:13, Namjae Jeon <linkinjeon@kernel.org>님이 작성:
>>
>> This patch add MAX_STREAM_PROT_LEN macro and check if stream protocol
>> length exceeds maximum value. opencode pdu size check in
>> ksmbd_pdu_size_has_room().
>>
>> Cc: Tom Talpey <tom@talpey.com>
>> Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
>> Cc: Ralph Böhme <slow@samba.org>
>> Cc: Steve French <smfrench@gmail.com>
>> Cc: Hyunchul Lee <hyc.lee@gmail.com>
>> Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
>> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
>> ---
>>  fs/ksmbd/connection.c | 10 ++++++----
>>  fs/ksmbd/smb_common.c |  6 ------
>>  fs/ksmbd/smb_common.h |  4 ++--
>>  3 files changed, 8 insertions(+), 12 deletions(-)
>>
>> diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c
>> index af086d35398a..48b18b4ec117 100644
>> --- a/fs/ksmbd/connection.c
>> +++ b/fs/ksmbd/connection.c
>> @@ -296,10 +296,12 @@ int ksmbd_conn_handler_loop(void *p)
>>                 pdu_size = get_rfc1002_len(hdr_buf);
>>                 ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size);
>>
>> -               /* make sure we have enough to get to SMB header end */
>> -               if (!ksmbd_pdu_size_has_room(pdu_size)) {
>> -                       ksmbd_debug(CONN, "SMB request too short (%u
>> bytes)\n",
>> -                                   pdu_size);
>> +               /*
>> +                * Check if pdu size is valid (min : smb header size,
>> +                * max : 0x00FFFFFF).
>> +                */
>> +               if (pdu_size < __SMB2_HEADER_STRUCTURE_SIZE ||
>> +                   pdu_size > MAX_STREAM_PROT_LEN) {
>>                         continue;
>>                 }
>>
>> diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c
>> index 5901b2884c60..20bd5b8e3c0a 100644
>> --- a/fs/ksmbd/smb_common.c
>> +++ b/fs/ksmbd/smb_common.c
>> @@ -21,7 +21,6 @@ static const char basechars[43] =
>> "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%";
>>  #define MAGIC_CHAR '~'
>>  #define PERIOD '.'
>>  #define mangle(V) ((char)(basechars[(V) % MANGLE_BASE]))
>> -#define KSMBD_MIN_SUPPORTED_HEADER_SIZE        (sizeof(struct smb2_hdr))
>>
>>  struct smb_protocol {
>>         int             index;
>> @@ -272,11 +271,6 @@ int ksmbd_init_smb_server(struct ksmbd_work *work)
>>         return 0;
>>  }
>>
>> -bool ksmbd_pdu_size_has_room(unsigned int pdu)
>> -{
>> -       return (pdu >= KSMBD_MIN_SUPPORTED_HEADER_SIZE - 4);
>> -}
>> -
>>  int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work, int
>> info_level,
>>                                       struct ksmbd_file *dir,
>>                                       struct ksmbd_dir_info *d_info,
>> diff --git a/fs/ksmbd/smb_common.h b/fs/ksmbd/smb_common.h
>> index 994abede27e9..6e79e7577f6b 100644
>> --- a/fs/ksmbd/smb_common.h
>> +++ b/fs/ksmbd/smb_common.h
>> @@ -48,6 +48,8 @@
>>  #define CIFS_DEFAULT_IOSIZE    (64 * 1024)
>>  #define MAX_CIFS_SMALL_BUFFER_SIZE 448 /* big enough for most */
>>
>> +#define MAX_STREAM_PROT_LEN    0x00FFFFFF
>
> Do we need to append "SMB" to this macro name?
I named it with the name defined in specification. That is, no problem.
> Looks good to me.
> Acked-by: Hyunchul Lee <hyc.lee@gmail.com>
Thanks for your review!
>
>
>> +
>>  /* Responses when opening a file. */
>>  #define F_SUPERSEDED   0
>>  #define F_OPENED       1
>> @@ -493,8 +495,6 @@ int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects,
>> __le16 dialects_count);
>>
>>  int ksmbd_init_smb_server(struct ksmbd_work *work);
>>
>> -bool ksmbd_pdu_size_has_room(unsigned int pdu);
>> -
>>  struct ksmbd_kstat;
>>  int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work,
>>                                       int info_level,
>> --
>> 2.25.1
>>
>
>
> --
> Thanks,
> Hyunchul
>
diff mbox series

Patch

diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c
index af086d35398a..48b18b4ec117 100644
--- a/fs/ksmbd/connection.c
+++ b/fs/ksmbd/connection.c
@@ -296,10 +296,12 @@  int ksmbd_conn_handler_loop(void *p)
 		pdu_size = get_rfc1002_len(hdr_buf);
 		ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size);
 
-		/* make sure we have enough to get to SMB header end */
-		if (!ksmbd_pdu_size_has_room(pdu_size)) {
-			ksmbd_debug(CONN, "SMB request too short (%u bytes)\n",
-				    pdu_size);
+		/*
+		 * Check if pdu size is valid (min : smb header size,
+		 * max : 0x00FFFFFF).
+		 */
+		if (pdu_size < __SMB2_HEADER_STRUCTURE_SIZE ||
+		    pdu_size > MAX_STREAM_PROT_LEN) {
 			continue;
 		}
 
diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c
index 5901b2884c60..20bd5b8e3c0a 100644
--- a/fs/ksmbd/smb_common.c
+++ b/fs/ksmbd/smb_common.c
@@ -21,7 +21,6 @@  static const char basechars[43] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%";
 #define MAGIC_CHAR '~'
 #define PERIOD '.'
 #define mangle(V) ((char)(basechars[(V) % MANGLE_BASE]))
-#define KSMBD_MIN_SUPPORTED_HEADER_SIZE	(sizeof(struct smb2_hdr))
 
 struct smb_protocol {
 	int		index;
@@ -272,11 +271,6 @@  int ksmbd_init_smb_server(struct ksmbd_work *work)
 	return 0;
 }
 
-bool ksmbd_pdu_size_has_room(unsigned int pdu)
-{
-	return (pdu >= KSMBD_MIN_SUPPORTED_HEADER_SIZE - 4);
-}
-
 int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work, int info_level,
 				      struct ksmbd_file *dir,
 				      struct ksmbd_dir_info *d_info,
diff --git a/fs/ksmbd/smb_common.h b/fs/ksmbd/smb_common.h
index 994abede27e9..6e79e7577f6b 100644
--- a/fs/ksmbd/smb_common.h
+++ b/fs/ksmbd/smb_common.h
@@ -48,6 +48,8 @@ 
 #define CIFS_DEFAULT_IOSIZE	(64 * 1024)
 #define MAX_CIFS_SMALL_BUFFER_SIZE 448 /* big enough for most */
 
+#define MAX_STREAM_PROT_LEN	0x00FFFFFF
+
 /* Responses when opening a file. */
 #define F_SUPERSEDED	0
 #define F_OPENED	1
@@ -493,8 +495,6 @@  int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count);
 
 int ksmbd_init_smb_server(struct ksmbd_work *work);
 
-bool ksmbd_pdu_size_has_room(unsigned int pdu);
-
 struct ksmbd_kstat;
 int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work,
 				      int info_level,