Commit a12a07a8 authored by David Disseldorp's avatar David Disseldorp Committed by Steve French
Browse files

ksmbd: avoid duplicate negotiate ctx offset increments 



Both pneg_ctxt and ctxt_size change in unison, with each adding the
length of the previously added context, rounded up to an eight byte
boundary.
Drop pneg_ctxt increments and instead use the ctxt_size offset when
passing output pointers to per-context helper functions. This slightly
simplifies offset tracking and shaves off a few text bytes.
Before (x86-64 gcc 7.5):
   text    data     bss     dec     hex filename
 213234    8677     672  222583   36577 ksmbd.ko

After:
   text    data     bss     dec     hex filename
 213218    8677     672  222567   36567 ksmbd.ko

Signed-off-by: default avatarDavid Disseldorp <ddiss@suse.de>
Acked-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 34e8ccf9

fs/ksmbd/smb2pdu.c

+10 −16
Original line number Diff line number Diff line
@@ -808,7 +808,7 @@ static void assemble_neg_contexts(struct ksmbd_conn *conn, 
				  struct smb2_negotiate_rsp *rsp,

				  void *smb2_buf_len)

{

	char *pneg_ctxt = (char *)rsp +

	char * const pneg_ctxt = (char *)rsp +

			le32_to_cpu(rsp->NegotiateContextOffset);

	int neg_ctxt_cnt = 1;

	int ctxt_size;
@@ -819,21 +819,17 @@ static void assemble_neg_contexts(struct ksmbd_conn *conn, 
			   conn->preauth_info->Preauth_HashId);

	inc_rfc1001_len(smb2_buf_len, AUTH_GSS_PADDING);

	ctxt_size = sizeof(struct smb2_preauth_neg_context);

	/* Round to 8 byte boundary */

	pneg_ctxt += round_up(sizeof(struct smb2_preauth_neg_context), 8);



	if (conn->cipher_type) {

		/* Round to 8 byte boundary */

		ctxt_size = round_up(ctxt_size, 8);

		ksmbd_debug(SMB,

			    "assemble SMB2_ENCRYPTION_CAPABILITIES context\n");

		build_encrypt_ctxt((struct smb2_encryption_neg_context *)pneg_ctxt,

		build_encrypt_ctxt((struct smb2_encryption_neg_context *)

				   (pneg_ctxt + ctxt_size),

				   conn->cipher_type);

		neg_ctxt_cnt++;

		ctxt_size += sizeof(struct smb2_encryption_neg_context) + 2;

		/* Round to 8 byte boundary */

		pneg_ctxt +=

			round_up(sizeof(struct smb2_encryption_neg_context) + 2,

				 8);

	}



	if (conn->compress_algorithm) {
@@ -841,31 +837,29 @@ static void assemble_neg_contexts(struct ksmbd_conn *conn, 
		ksmbd_debug(SMB,

			    "assemble SMB2_COMPRESSION_CAPABILITIES context\n");

		/* Temporarily set to SMB3_COMPRESS_NONE */

		build_compression_ctxt((struct smb2_compression_capabilities_context *)pneg_ctxt,

		build_compression_ctxt((struct smb2_compression_capabilities_context *)

				       (pneg_ctxt + ctxt_size),

				       conn->compress_algorithm);

		neg_ctxt_cnt++;

		ctxt_size += sizeof(struct smb2_compression_capabilities_context) + 2;

		/* Round to 8 byte boundary */

		pneg_ctxt += round_up(sizeof(struct smb2_compression_capabilities_context) + 2,

				      8);

	}



	if (conn->posix_ext_supported) {

		ctxt_size = round_up(ctxt_size, 8);

		ksmbd_debug(SMB,

			    "assemble SMB2_POSIX_EXTENSIONS_AVAILABLE context\n");

		build_posix_ctxt((struct smb2_posix_neg_context *)pneg_ctxt);

		build_posix_ctxt((struct smb2_posix_neg_context *)

				 (pneg_ctxt + ctxt_size));

		neg_ctxt_cnt++;

		ctxt_size += sizeof(struct smb2_posix_neg_context);

		/* Round to 8 byte boundary */

		pneg_ctxt += round_up(sizeof(struct smb2_posix_neg_context), 8);

	}



	if (conn->signing_negotiated) {

		ctxt_size = round_up(ctxt_size, 8);

		ksmbd_debug(SMB,

			    "assemble SMB2_SIGNING_CAPABILITIES context\n");

		build_sign_cap_ctxt((struct smb2_signing_capabilities *)pneg_ctxt,

		build_sign_cap_ctxt((struct smb2_signing_capabilities *)

				    (pneg_ctxt + ctxt_size),

				    conn->signing_algorithm);

		neg_ctxt_cnt++;

		ctxt_size += sizeof(struct smb2_signing_capabilities) + 2;