[PATCH v2 3/7] ksmbd: add validation in smb2_ioctl

Namjae Jeon
2021-09-25T13:17:12Z

Add validation for request/response buffer size check in smb2_ioctl and
fsctl_copychunk() take copychunk_ioctl_req pointer and the other arguments
instead of smb2_ioctl_req structure and remove an unused smb2_ioctl_req
argument of fsctl_validate_negotiate_info.

Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
fs/ksmbd/smb2pdu.c | 96 +++++++++++++++++++++++++++++++++++-----------
fs/ksmbd/vfs.c | 2 +-
fs/ksmbd/vfs.h | 2 +-
3 files changed, 75 insertions(+), 25 deletions(-)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 2f7ce7f28eb6..c54e9e35fbc5 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -6909,24 +6909,26 @@ int smb2_lock(struct ksmbd_work *work)
return err;
}

-static int fsctl_copychunk(struct ksmbd_work *work, struct smb2_ioctl_req *req,
+static int fsctl_copychunk(struct ksmbd_work *work,
+ struct copychunk_ioctl_req *ci_req,
+ unsigned int cnt_code,
+ unsigned int input_count,
+ unsigned long long volatile_id,
+ unsigned long long persistent_id,
struct smb2_ioctl_rsp *rsp)
{
- struct copychunk_ioctl_req *ci_req;
struct copychunk_ioctl_rsp *ci_rsp;
struct ksmbd_file *src_fp = NULL, *dst_fp = NULL;
struct srv_copychunk *chunks;
unsigned int i, chunk_count, chunk_count_written = 0;
unsigned int chunk_size_written = 0;
loff_t total_size_written = 0;
- int ret, cnt_code;
+ int ret = 0;

- cnt_code = le32_to_cpu(req->CntCode);
- ci_req = (struct copychunk_ioctl_req *)&req->Buffer[0];
ci_rsp = (struct copychunk_ioctl_rsp *)&rsp->Buffer[0];

- rsp->VolatileFileId = req->VolatileFileId;
- rsp->PersistentFileId = req->PersistentFileId;
+ rsp->VolatileFileId = cpu_to_le64(volatile_id);
+ rsp->PersistentFileId = cpu_to_le64(persistent_id);
ci_rsp->ChunksWritten =
cpu_to_le32(ksmbd_server_side_copy_max_chunk_count());
ci_rsp->ChunkBytesWritten =
@@ -6936,12 +6938,13 @@ static int fsctl_copychunk(struct ksmbd_work *work, struct smb2_ioctl_req *req,

chunks = (struct srv_copychunk *)&ci_req->Chunks[0];
chunk_count = le32_to_cpu(ci_req->ChunkCount);
+ if (chunk_count == 0)
+ goto out;
total_size_written = 0;

/* verify the SRV_COPYCHUNK_COPY packet */
if (chunk_count > ksmbd_server_side_copy_max_chunk_count() ||
- le32_to_cpu(req->InputCount) <
- offsetof(struct copychunk_ioctl_req, Chunks) +
+ input_count < offsetof(struct copychunk_ioctl_req, Chunks) +
chunk_count * sizeof(struct srv_copychunk)) {
rsp->hdr.Status = STATUS_INVALID_PARAMETER;
return -EINVAL;
@@ -6962,9 +6965,7 @@ static int fsctl_copychunk(struct ksmbd_work *work, struct smb2_ioctl_req *req,

src_fp = ksmbd_lookup_foreign_fd(work,
le64_to_cpu(ci_req->ResumeKey[0]));
- dst_fp = ksmbd_lookup_fd_slow(work,
- le64_to_cpu(req->VolatileFileId),
- le64_to_cpu(req->PersistentFileId));
+ dst_fp = ksmbd_lookup_fd_slow(work, volatile_id, persistent_id);
ret = -EINVAL;
if (!src_fp ||
src_fp->persistent_id != le64_to_cpu(ci_req->ResumeKey[1])) {
@@ -7039,8 +7040,8 @@ static __be32 idev_ipv4_address(struct in_device *idev)
}

static int fsctl_query_iface_info_ioctl(struct ksmbd_conn *conn,
- struct smb2_ioctl_req *req,
- struct smb2_ioctl_rsp *rsp)
+ struct smb2_ioctl_rsp *rsp,
+ int out_buf_len)
{
struct network_interface_info_ioctl_rsp *nii_rsp = NULL;
int nbytes = 0;
@@ -7123,6 +7124,8 @@ static int fsctl_query_iface_info_ioctl(struct ksmbd_conn *conn,
sockaddr_storage->addr6.ScopeId = 0;
}

+ if (out_buf_len - nbytes < sizeof(struct network_interface_info_ioctl_rsp))
+ break;
nbytes += sizeof(struct network_interface_info_ioctl_rsp);
}
rtnl_unlock();
@@ -7143,11 +7146,16 @@ static int fsctl_query_iface_info_ioctl(struct ksmbd_conn *conn,

static int fsctl_validate_negotiate_info(struct ksmbd_conn *conn,
struct validate_negotiate_info_req *neg_req,
- struct validate_negotiate_info_rsp *neg_rsp)
+ struct validate_negotiate_info_rsp *neg_rsp,
+ unsigned int in_buf_len)
{
int ret = 0;
int dialect;

+ if (in_buf_len < sizeof(struct validate_negotiate_info_req) +
+ le16_to_cpu(neg_req->DialectCount) * sizeof(__le16))
+ return -EINVAL;
+
dialect = ksmbd_lookup_dialect_by_id(neg_req->Dialects,
neg_req->DialectCount);
if (dialect == BAD_PROT_ID || dialect != conn->dialect) {
@@ -7181,7 +7189,7 @@ static int fsctl_validate_negotiate_info(struct ksmbd_conn *conn,
static int fsctl_query_allocated_ranges(struct ksmbd_work *work, u64 id,
struct file_allocated_range_buffer *qar_req,
struct file_allocated_range_buffer *qar_rsp,
- int in_count, int *out_count)
+ unsigned int in_count, unsigned int *out_count)
{
struct ksmbd_file *fp;
loff_t start, length;
@@ -7208,7 +7216,8 @@ static int fsctl_query_allocated_ranges(struct ksmbd_work *work, u64 id,
}

static int fsctl_pipe_transceive(struct ksmbd_work *work, u64 id,
- int out_buf_len, struct smb2_ioctl_req *req,
+ unsigned int out_buf_len,
+ struct smb2_ioctl_req *req,
struct smb2_ioctl_rsp *rsp)
{
struct ksmbd_rpc_command *rpc_resp;
@@ -7322,8 +7331,7 @@ int smb2_ioctl(struct ksmbd_work *work)
{
struct smb2_ioctl_req *req;
struct smb2_ioctl_rsp *rsp, *rsp_org;
- int cnt_code, nbytes = 0;
- int out_buf_len;
+ unsigned int cnt_code, nbytes = 0, out_buf_len, in_buf_len;
u64 id = KSMBD_NO_FID;
struct ksmbd_conn *conn = work->conn;
int ret = 0;
@@ -7352,7 +7360,8 @@ int smb2_ioctl(struct ksmbd_work *work)

cnt_code = le32_to_cpu(req->CntCode);
out_buf_len = le32_to_cpu(req->MaxOutputResponse);
- out_buf_len = min(KSMBD_IPC_MAX_PAYLOAD, out_buf_len);
+ out_buf_len = min_t(u32, MAX_STREAM_PROT_LEN, out_buf_len);
+ in_buf_len = le32_to_cpu(req->InputCount);

switch (cnt_code) {
case FSCTL_DFS_GET_REFERRALS:
@@ -7380,6 +7389,7 @@ int smb2_ioctl(struct ksmbd_work *work)
break;
}
case FSCTL_PIPE_TRANSCEIVE:
+ out_buf_len = min_t(u32, KSMBD_IPC_MAX_PAYLOAD, out_buf_len);
nbytes = fsctl_pipe_transceive(work, id, out_buf_len, req, rsp);
break;
case FSCTL_VALIDATE_NEGOTIATE_INFO:
@@ -7388,9 +7398,16 @@ int smb2_ioctl(struct ksmbd_work *work)
goto out;
}

+ if (in_buf_len < sizeof(struct validate_negotiate_info_req))
+ return -EINVAL;
+
+ if (out_buf_len < sizeof(struct validate_negotiate_info_rsp))
+ return -EINVAL;
+
ret = fsctl_validate_negotiate_info(conn,
(struct validate_negotiate_info_req *)&req->Buffer[0],
- (struct validate_negotiate_info_rsp *)&rsp->Buffer[0]);
+ (struct validate_negotiate_info_rsp *)&rsp->Buffer[0],
+ in_buf_len);
if (ret < 0)
goto out;

@@ -7399,7 +7416,7 @@ int smb2_ioctl(struct ksmbd_work *work)
rsp->VolatileFileId = cpu_to_le64(SMB2_NO_FID);
break;
case FSCTL_QUERY_NETWORK_INTERFACE_INFO:
- nbytes = fsctl_query_iface_info_ioctl(conn, req, rsp);
+ nbytes = fsctl_query_iface_info_ioctl(conn, rsp, out_buf_len);
if (nbytes < 0)
goto out;
break;
@@ -7426,15 +7443,33 @@ int smb2_ioctl(struct ksmbd_work *work)
goto out;
}

+ if (in_buf_len < sizeof(struct copychunk_ioctl_req)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
if (out_buf_len < sizeof(struct copychunk_ioctl_rsp)) {
ret = -EINVAL;
goto out;
}

nbytes = sizeof(struct copychunk_ioctl_rsp);
- fsctl_copychunk(work, req, rsp);
+ rsp->VolatileFileId = req->VolatileFileId;
+ rsp->PersistentFileId = req->PersistentFileId;
+ fsctl_copychunk(work,
+ (struct copychunk_ioctl_req *)&req->Buffer[0],
+ le32_to_cpu(req->CntCode),
+ le32_to_cpu(req->InputCount),
+ le64_to_cpu(req->VolatileFileId),
+ le64_to_cpu(req->PersistentFileId),
+ rsp);
break;
case FSCTL_SET_SPARSE:
+ if (in_buf_len < sizeof(struct file_sparse)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
ret = fsctl_set_sparse(work, id,
(struct file_sparse *)&req->Buffer[0]);
if (ret < 0)
@@ -7453,6 +7488,11 @@ int smb2_ioctl(struct ksmbd_work *work)
goto out;
}

+ if (in_buf_len < sizeof(struct file_zero_data_information)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
zero_data =
(struct file_zero_data_information *)&req->Buffer[0];

@@ -7472,6 +7512,11 @@ int smb2_ioctl(struct ksmbd_work *work)
break;
}
case FSCTL_QUERY_ALLOCATED_RANGES:
+ if (in_buf_len < sizeof(struct file_allocated_range_buffer)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
ret = fsctl_query_allocated_ranges(work, id,
(struct file_allocated_range_buffer *)&req->Buffer[0],
(struct file_allocated_range_buffer *)&rsp->Buffer[0],
@@ -7512,6 +7557,11 @@ int smb2_ioctl(struct ksmbd_work *work)
struct duplicate_extents_to_file *dup_ext;
loff_t src_off, dst_off, length, cloned;

+ if (in_buf_len < sizeof(struct duplicate_extents_to_file)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
dup_ext = (struct duplicate_extents_to_file *)&req->Buffer[0];

fp_in = ksmbd_lookup_fd_slow(work, dup_ext->VolatileFileHandle,
diff --git a/fs/ksmbd/vfs.c b/fs/ksmbd/vfs.c
index b41954294d38..835b384b0895 100644
--- a/fs/ksmbd/vfs.c
+++ b/fs/ksmbd/vfs.c
@@ -1023,7 +1023,7 @@ int ksmbd_vfs_zero_data(struct ksmbd_work *work, struct ksmbd_file *fp,

int ksmbd_vfs_fqar_lseek(struct ksmbd_file *fp, loff_t start, loff_t length,
struct file_allocated_range_buffer *ranges,
- int in_count, int *out_count)
+ unsigned int in_count, unsigned int *out_count)
{
struct file *f = fp->filp;
struct inode *inode = file_inode(fp->filp);
diff --git a/fs/ksmbd/vfs.h b/fs/ksmbd/vfs.h
index 7b1dcaa3fbdc..b0d5b8feb4a3 100644
--- a/fs/ksmbd/vfs.h
+++ b/fs/ksmbd/vfs.h
@@ -166,7 +166,7 @@ int ksmbd_vfs_zero_data(struct ksmbd_work *work, struct ksmbd_file *fp,
struct file_allocated_range_buffer;
int ksmbd_vfs_fqar_lseek(struct ksmbd_file *fp, loff_t start, loff_t length,
struct file_allocated_range_buffer *ranges,
- int in_count, int *out_count);
+ unsigned int in_count, unsigned int *out_count);
int ksmbd_vfs_unlink(struct user_namespace *user_ns,
struct dentry *dir, struct dentry *dentry);
void *ksmbd_vfs_init_kstat(char **p, struct ksmbd_kstat *ksmbd_kstat);
--
2.25.1