From 49d9f6ad1ee064c52662538fc48b2ada33ae3fd2 Mon Sep 17 00:00:00 2001 From: David Disseldorp Date: Sun, 31 Dec 2023 16:12:34 +0900 Subject: ksmbd: avoid duplicate negotiate ctx offset increments [ Upstream commit a12a07a85aff72e19520328f78b1c64d2281a1ec ] 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: David Disseldorp Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/smb/server/smb2pdu.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index c7d43c83d233..92e657097243 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -838,7 +838,7 @@ 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; @@ -849,21 +849,17 @@ 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) { @@ -871,31 +867,29 @@ 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; -- cgit v1.2.3