Move some large data structures off the stack and into dynamically
allocated memory in the function smb2_ioctl_query_info
Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
---
fs/cifs/smb2ops.c | 58 +++++++++++++++++++++++++++++++++----------------------
1 file changed, 35 insertions(+), 23 deletions(-)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index f829f4165d38..fa5c79f64c0b 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1452,6 +1452,16 @@ SMB2_request_res_key(const unsigned int xid, struct cifs_tcon *tcon,
return rc;
}
+struct iqi_vars {
+ struct smb_rqst rqst[3];
+ struct kvec rsp_iov[3];
+ struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
+ struct kvec qi_iov[1];
+ struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
+ struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
+ struct kvec close_iov[1];
+};
+
static int
smb2_ioctl_query_info(const unsigned int xid,
struct cifs_tcon *tcon,
@@ -1459,6 +1469,9 @@ smb2_ioctl_query_info(const unsigned int xid,
__le16 *path, int is_dir,
unsigned long p)
{
+ struct iqi_vars *vars;
+ struct smb_rqst *rqst;
+ struct kvec *rsp_iov;
struct cifs_ses *ses = tcon->ses;
char __user *arg = (char __user *)p;
struct smb_query_info qi;
@@ -1468,45 +1481,47 @@ smb2_ioctl_query_info(const unsigned int xid,
struct smb2_query_info_rsp *qi_rsp = NULL;
struct smb2_ioctl_rsp *io_rsp = NULL;
void *buffer = NULL;
- struct smb_rqst rqst[3];
int resp_buftype[3];
- struct kvec rsp_iov[3];
- struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
struct cifs_open_parms oparms;
u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
struct cifs_fid fid;
- struct kvec qi_iov[1];
- struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
- struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
- struct kvec close_iov[1];
unsigned int size[2];
void *data[2];
int create_options = is_dir ? CREATE_NOT_FILE : CREATE_NOT_DIR;
- memset(rqst, 0, sizeof(rqst));
+ vars = kzalloc(sizeof(*vars), GFP_ATOMIC);
+ if (vars == NULL)
+ return -ENOMEM;
+ rqst = &vars->rqst[0];
+ rsp_iov = &vars->rsp_iov[0];
+
resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
- memset(rsp_iov, 0, sizeof(rsp_iov));
if (copy_from_user(&qi, arg, sizeof(struct smb_query_info)))
- return -EFAULT;
+ goto e_fault;
- if (qi.output_buffer_length > 1024)
+ if (qi.output_buffer_length > 1024) {
+ kfree(vars);
return -EINVAL;
+ }
- if (!ses || !(ses->server))
+ if (!ses || !(ses->server)) {
+ kfree(vars);
return -EIO;
+ }
if (smb3_encryption_required(tcon))
flags |= CIFS_TRANSFORM_REQ;
buffer = memdup_user(arg + sizeof(struct smb_query_info),
qi.output_buffer_length);
- if (IS_ERR(buffer))
+ if (IS_ERR(buffer)) {
+ kfree(vars);
return PTR_ERR(buffer);
+ }
/* Open */
- memset(&open_iov, 0, sizeof(open_iov));
- rqst[0].rq_iov = open_iov;
+ rqst[0].rq_iov = &vars->open_iov[0];
rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;
memset(&oparms, 0, sizeof(oparms));
@@ -1548,8 +1563,7 @@ smb2_ioctl_query_info(const unsigned int xid,
if (!capable(CAP_SYS_ADMIN))
rc = -EPERM;
else {
- memset(&io_iov, 0, sizeof(io_iov));
- rqst[1].rq_iov = io_iov;
+ rqst[1].rq_iov = &vars->io_iov[0];
rqst[1].rq_nvec = SMB2_IOCTL_IOV_SIZE;
rc = SMB2_ioctl_init(tcon, &rqst[1],
@@ -1565,8 +1579,7 @@ smb2_ioctl_query_info(const unsigned int xid,
if (!capable(CAP_SYS_ADMIN))
rc = -EPERM;
else {
- memset(&si_iov, 0, sizeof(si_iov));
- rqst[1].rq_iov = si_iov;
+ rqst[1].rq_iov = &vars->si_iov[0];
rqst[1].rq_nvec = 1;
size[0] = 8;
@@ -1579,8 +1592,7 @@ smb2_ioctl_query_info(const unsigned int xid,
SMB2_O_INFO_FILE, 0, data, size);
}
} else if (qi.flags == PASSTHRU_QUERY_INFO) {
- memset(&qi_iov, 0, sizeof(qi_iov));
- rqst[1].rq_iov = qi_iov;
+ rqst[1].rq_iov = &vars->qi_iov[0];
rqst[1].rq_nvec = 1;
rc = SMB2_query_info_init(tcon, &rqst[1], COMPOUND_FID,
@@ -1599,8 +1611,7 @@ smb2_ioctl_query_info(const unsigned int xid,
smb2_set_related(&rqst[1]);
/* Close */
- memset(&close_iov, 0, sizeof(close_iov));
- rqst[2].rq_iov = close_iov;
+ rqst[2].rq_iov = &vars->close_iov[0];
rqst[2].rq_nvec = 1;
rc = SMB2_close_init(tcon, &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
@@ -1649,6 +1660,7 @@ smb2_ioctl_query_info(const unsigned int xid,
}
iqinf_exit:
+ kfree(vars);
kfree(buffer);
SMB2_open_free(&rqst[0]);
if (qi.flags & PASSTHRU_FSCTL)
--
2.13.6
