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 <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Ronnie Sahlberg 2020-05-20 12:19:59 +10:00 committed by Steve French
parent baf3f08ef4
commit a7d5c29462

View File

@ -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;
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;
memset(&open_iov, 0, sizeof(open_iov));
rqst[num_rqst].rq_iov = open_iov;
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;
}