From a7d5c294628088781da9e91cbb034d61c3a71f71 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Wed, 20 May 2020 12:19:59 +1000 Subject: cifs: reduce stack use in smb2_compound_op Move a lot of structures and arrays off the stack and into a dynamically allocated structure instead. Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French --- fs/cifs/smb2inode.c | 92 +++++++++++++++++++++++++++-------------------------- 1 file changed, 47 insertions(+), 45 deletions(-) (limited to 'fs/cifs/smb2inode.c') diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c index a8c301ae00ed..19115a9088ea 100644 --- a/fs/cifs/smb2inode.c +++ b/fs/cifs/smb2inode.c @@ -47,6 +47,18 @@ free_set_inf_compound(struct smb_rqst *rqst) } +struct cop_vars { + struct cifs_open_parms oparms; + struct kvec rsp_iov[3]; + struct smb_rqst rqst[3]; + struct kvec open_iov[SMB2_CREATE_IOV_SIZE]; + struct kvec qi_iov[1]; + struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE]; + struct kvec close_iov[1]; + struct smb2_file_rename_info rename_info; + struct smb2_file_link_info link_info; +}; + static int smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, struct cifs_sb_info *cifs_sb, const char *full_path, @@ -54,35 +66,33 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, __u32 create_options, umode_t mode, void *ptr, int command, struct cifsFileInfo *cfile) { + struct cop_vars *vars = NULL; + struct kvec *rsp_iov; + struct smb_rqst *rqst; int rc; __le16 *utf16_path = NULL; __u8 oplock = SMB2_OPLOCK_LEVEL_NONE; - struct cifs_open_parms oparms; struct cifs_fid fid; struct cifs_ses *ses = tcon->ses; int num_rqst = 0; - struct smb_rqst rqst[3]; int resp_buftype[3]; - struct kvec rsp_iov[3]; - struct kvec open_iov[SMB2_CREATE_IOV_SIZE]; - struct kvec qi_iov[1]; - struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE]; - struct kvec close_iov[1]; struct smb2_query_info_rsp *qi_rsp = NULL; int flags = 0; __u8 delete_pending[8] = {1, 0, 0, 0, 0, 0, 0, 0}; unsigned int size[2]; void *data[2]; - struct smb2_file_rename_info rename_info; - struct smb2_file_link_info link_info; int len; + vars = kzalloc(sizeof(*vars), GFP_ATOMIC); + if (vars == NULL) + return -ENOMEM; + rqst = &vars->rqst[0]; + rsp_iov = &vars->rsp_iov[0]; + if (smb3_encryption_required(tcon)) flags |= CIFS_TRANSFORM_REQ; - memset(rqst, 0, sizeof(rqst)); resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER; - memset(rsp_iov, 0, sizeof(rsp_iov)); /* We already have a handle so we can skip the open */ if (cfile) @@ -95,19 +105,17 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, goto finished; } - memset(&oparms, 0, sizeof(struct cifs_open_parms)); - oparms.tcon = tcon; - oparms.desired_access = desired_access; - oparms.disposition = create_disposition; - oparms.create_options = cifs_create_options(cifs_sb, create_options); - oparms.fid = &fid; - oparms.reconnect = false; - oparms.mode = mode; - - memset(&open_iov, 0, sizeof(open_iov)); - rqst[num_rqst].rq_iov = open_iov; + vars->oparms.tcon = tcon; + vars->oparms.desired_access = desired_access; + vars->oparms.disposition = create_disposition; + vars->oparms.create_options = cifs_create_options(cifs_sb, create_options); + vars->oparms.fid = &fid; + vars->oparms.reconnect = false; + vars->oparms.mode = mode; + + rqst[num_rqst].rq_iov = &vars->open_iov[0]; rqst[num_rqst].rq_nvec = SMB2_CREATE_IOV_SIZE; - rc = SMB2_open_init(tcon, &rqst[num_rqst], &oplock, &oparms, + rc = SMB2_open_init(tcon, &rqst[num_rqst], &oplock, &vars->oparms, utf16_path); kfree(utf16_path); if (rc) @@ -121,8 +129,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, /* Operation */ switch (command) { case SMB2_OP_QUERY_INFO: - memset(&qi_iov, 0, sizeof(qi_iov)); - rqst[num_rqst].rq_iov = qi_iov; + rqst[num_rqst].rq_iov = &vars->qi_iov[0]; rqst[num_rqst].rq_nvec = 1; if (cfile) @@ -164,8 +171,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, trace_smb3_mkdir_enter(xid, ses->Suid, tcon->tid, full_path); break; case SMB2_OP_RMDIR: - memset(&si_iov, 0, sizeof(si_iov)); - rqst[num_rqst].rq_iov = si_iov; + rqst[num_rqst].rq_iov = &vars->si_iov[0]; rqst[num_rqst].rq_nvec = 1; size[0] = 1; /* sizeof __u8 See MS-FSCC section 2.4.11 */ @@ -182,8 +188,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, trace_smb3_rmdir_enter(xid, ses->Suid, tcon->tid, full_path); break; case SMB2_OP_SET_EOF: - memset(&si_iov, 0, sizeof(si_iov)); - rqst[num_rqst].rq_iov = si_iov; + rqst[num_rqst].rq_iov = &vars->si_iov[0]; rqst[num_rqst].rq_nvec = 1; size[0] = 8; /* sizeof __le64 */ @@ -200,8 +205,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, trace_smb3_set_eof_enter(xid, ses->Suid, tcon->tid, full_path); break; case SMB2_OP_SET_INFO: - memset(&si_iov, 0, sizeof(si_iov)); - rqst[num_rqst].rq_iov = si_iov; + rqst[num_rqst].rq_iov = &vars->si_iov[0]; rqst[num_rqst].rq_nvec = 1; @@ -233,18 +237,17 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, full_path); break; case SMB2_OP_RENAME: - memset(&si_iov, 0, sizeof(si_iov)); - rqst[num_rqst].rq_iov = si_iov; + rqst[num_rqst].rq_iov = &vars->si_iov[0]; rqst[num_rqst].rq_nvec = 2; len = (2 * UniStrnlen((wchar_t *)ptr, PATH_MAX)); - rename_info.ReplaceIfExists = 1; - rename_info.RootDirectory = 0; - rename_info.FileNameLength = cpu_to_le32(len); + vars->rename_info.ReplaceIfExists = 1; + vars->rename_info.RootDirectory = 0; + vars->rename_info.FileNameLength = cpu_to_le32(len); size[0] = sizeof(struct smb2_file_rename_info); - data[0] = &rename_info; + data[0] = &vars->rename_info; size[1] = len + 2 /* null */; data[1] = (__le16 *)ptr; @@ -271,18 +274,17 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, trace_smb3_rename_enter(xid, ses->Suid, tcon->tid, full_path); break; case SMB2_OP_HARDLINK: - memset(&si_iov, 0, sizeof(si_iov)); - rqst[num_rqst].rq_iov = si_iov; + rqst[num_rqst].rq_iov = &vars->si_iov[0]; rqst[num_rqst].rq_nvec = 2; len = (2 * UniStrnlen((wchar_t *)ptr, PATH_MAX)); - link_info.ReplaceIfExists = 0; - link_info.RootDirectory = 0; - link_info.FileNameLength = cpu_to_le32(len); + vars->link_info.ReplaceIfExists = 0; + vars->link_info.RootDirectory = 0; + vars->link_info.FileNameLength = cpu_to_le32(len); size[0] = sizeof(struct smb2_file_link_info); - data[0] = &link_info; + data[0] = &vars->link_info; size[1] = len + 2 /* null */; data[1] = (__le16 *)ptr; @@ -308,8 +310,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, if (cfile) goto after_close; /* Close */ - memset(&close_iov, 0, sizeof(close_iov)); - rqst[num_rqst].rq_iov = close_iov; + rqst[num_rqst].rq_iov = &vars->close_iov[0]; rqst[num_rqst].rq_nvec = 1; rc = SMB2_close_init(tcon, &rqst[num_rqst], COMPOUND_FID, COMPOUND_FID, false); @@ -420,6 +421,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon, free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base); free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base); free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base); + kfree(vars); return rc; } -- cgit v1.2.3