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@xxxxxxxxxx> Cc: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx> Cc: Ralph Böhme <slow@xxxxxxxxx> Cc: Steve French <smfrench@xxxxxxxxx> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Acked-by: Hyunchul Lee <hyc.lee@xxxxxxxxx> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx> --- 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 1da67217698d..36fd9695fbc5 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; @@ -267,11 +266,6 @@ 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 d7df19c97c4c..b8d225f7dbfc 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 @@ -492,8 +494,6 @@ 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