[SRU][J][PATCH 1/1] ksmbd: fix potencial out-of-bounds when buffer offset is invalid
Bethany Jamison
bethany.jamison at canonical.com
Wed Jun 26 21:14:27 UTC 2024
From: Namjae Jeon <linkinjeon at kernel.org>
I found potencial out-of-bounds when buffer offset fields of a few requests
is invalid. This patch set the minimum value of buffer offset field to
->Buffer offset to validate buffer length.
Cc: stable at vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon at kernel.org>
Signed-off-by: Steve French <stfrench at microsoft.com>
(backported from commit c6cd2e8d2d9aa7ee35b1fa6a668e32a22a9753da)
[bjamison: unrelated context conflicts in neighboring lines, I applied
fix changes as given]
CVE-2024-26952
Signed-off-by: Bethany Jamison <bethany.jamison at canonical.com>
---
fs/ksmbd/smb2misc.c | 22 +++++++++++++++------
fs/ksmbd/smb2pdu.c | 48 ++++++++++++++++++++++++---------------------
2 files changed, 42 insertions(+), 28 deletions(-)
diff --git a/fs/ksmbd/smb2misc.c b/fs/ksmbd/smb2misc.c
index 4d1211bde1900..9e54ecc9d4ada 100644
--- a/fs/ksmbd/smb2misc.c
+++ b/fs/ksmbd/smb2misc.c
@@ -102,7 +102,9 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
*len = le16_to_cpu(((struct smb2_sess_setup_req *)hdr)->SecurityBufferLength);
break;
case SMB2_TREE_CONNECT:
- *off = le16_to_cpu(((struct smb2_tree_connect_req *)hdr)->PathOffset);
+ *off = max_t(unsigned short int,
+ le16_to_cpu(((struct smb2_tree_connect_req *)hdr)->PathOffset),
+ offsetof(struct smb2_tree_connect_req, Buffer));
*len = le16_to_cpu(((struct smb2_tree_connect_req *)hdr)->PathLength);
break;
case SMB2_CREATE:
@@ -129,11 +131,15 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
break;
}
case SMB2_QUERY_INFO:
- *off = le16_to_cpu(((struct smb2_query_info_req *)hdr)->InputBufferOffset);
+ *off = max_t(unsigned int,
+ le16_to_cpu(((struct smb2_query_info_req *)hdr)->InputBufferOffset),
+ offsetof(struct smb2_query_info_req, Buffer));
*len = le32_to_cpu(((struct smb2_query_info_req *)hdr)->InputBufferLength);
break;
case SMB2_SET_INFO:
- *off = le16_to_cpu(((struct smb2_set_info_req *)hdr)->BufferOffset);
+ *off = max_t(unsigned int,
+ le16_to_cpu(((struct smb2_set_info_req *)hdr)->BufferOffset),
+ offsetof(struct smb2_set_info_req, Buffer));
*len = le32_to_cpu(((struct smb2_set_info_req *)hdr)->BufferLength);
break;
case SMB2_READ:
@@ -143,7 +149,7 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
case SMB2_WRITE:
if (((struct smb2_write_req *)hdr)->DataOffset ||
((struct smb2_write_req *)hdr)->Length) {
- *off = max_t(unsigned int,
+ *off = max_t(unsigned short int,
le16_to_cpu(((struct smb2_write_req *)hdr)->DataOffset),
offsetof(struct smb2_write_req, Buffer) - 4);
*len = le32_to_cpu(((struct smb2_write_req *)hdr)->Length);
@@ -154,7 +160,9 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
*len = le16_to_cpu(((struct smb2_write_req *)hdr)->WriteChannelInfoLength);
break;
case SMB2_QUERY_DIRECTORY:
- *off = le16_to_cpu(((struct smb2_query_directory_req *)hdr)->FileNameOffset);
+ *off = max_t(unsigned short int,
+ le16_to_cpu(((struct smb2_query_directory_req *)hdr)->FileNameOffset),
+ offsetof(struct smb2_query_directory_req, Buffer));
*len = le16_to_cpu(((struct smb2_query_directory_req *)hdr)->FileNameLength);
break;
case SMB2_LOCK:
@@ -169,7 +177,9 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
break;
}
case SMB2_IOCTL:
- *off = le32_to_cpu(((struct smb2_ioctl_req *)hdr)->InputOffset);
+ *off = max_t(unsigned int,
+ le32_to_cpu(((struct smb2_ioctl_req *)hdr)->InputOffset),
+ offsetof(struct smb2_ioctl_req, Buffer));
*len = le32_to_cpu(((struct smb2_ioctl_req *)hdr)->InputCount);
break;
default:
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 495d76fa26b47..446926fae4109 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -1955,7 +1955,7 @@ int smb2_tree_connect(struct ksmbd_work *work)
WORK_BUFFERS(work, req, rsp);
- treename = smb_strndup_from_utf16(req->Buffer,
+ treename = smb_strndup_from_utf16((char *)req + le16_to_cpu(req->PathOffset),
le16_to_cpu(req->PathLength), true,
conn->local_nls);
if (IS_ERR(treename)) {
@@ -2705,7 +2705,7 @@ int smb2_open(struct ksmbd_work *work)
goto err_out2;
}
- name = smb2_get_name(req->Buffer,
+ name = smb2_get_name((char *)req + le16_to_cpu(req->NameOffset),
le16_to_cpu(req->NameLength),
work->conn->local_nls);
if (IS_ERR(name)) {
@@ -4077,7 +4077,7 @@ int smb2_query_dir(struct ksmbd_work *work)
}
srch_flag = req->Flags;
- srch_ptr = smb_strndup_from_utf16(req->Buffer,
+ srch_ptr = smb_strndup_from_utf16((char *)req + le16_to_cpu(req->FileNameOffset),
le16_to_cpu(req->FileNameLength), 1,
conn->local_nls);
if (IS_ERR(srch_ptr)) {
@@ -4337,7 +4337,8 @@ static int smb2_get_ea(struct ksmbd_work *work, struct ksmbd_file *fp,
sizeof(struct smb2_ea_info_req))
return -EINVAL;
- ea_req = (struct smb2_ea_info_req *)req->Buffer;
+ ea_req = (struct smb2_ea_info_req *)((char *)req +
+ le16_to_cpu(req->InputBufferOffset));
} else {
/* need to send all EAs, if no specific EA is requested*/
if (le32_to_cpu(req->Flags) & SL_RETURN_SINGLE_ENTRY)
@@ -5943,6 +5944,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
struct ksmbd_share_config *share)
{
unsigned int buf_len = le32_to_cpu(req->BufferLength);
+ char *buffer = (char *)req + le16_to_cpu(req->BufferOffset);
switch (req->FileInfoClass) {
case FILE_BASIC_INFORMATION:
@@ -5950,7 +5952,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
if (buf_len < sizeof(struct smb2_file_basic_info))
return -EINVAL;
- return set_file_basic_info(fp, (struct smb2_file_basic_info *)req->Buffer, share);
+ return set_file_basic_info(fp, (struct smb2_file_basic_info *)buffer, share);
}
case FILE_ALLOCATION_INFORMATION:
{
@@ -5958,7 +5960,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
return -EINVAL;
return set_file_allocation_info(work, fp,
- (struct smb2_file_alloc_info *)req->Buffer);
+ (struct smb2_file_alloc_info *)buffer);
}
case FILE_END_OF_FILE_INFORMATION:
{
@@ -5966,7 +5968,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
return -EINVAL;
return set_end_of_file_info(work, fp,
- (struct smb2_file_eof_info *)req->Buffer);
+ (struct smb2_file_eof_info *)buffer);
}
case FILE_RENAME_INFORMATION:
{
@@ -5974,7 +5976,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
return -EINVAL;
return set_rename_info(work, fp,
- (struct smb2_file_rename_info *)req->Buffer,
+ (struct smb2_file_rename_info *)buffer,
buf_len);
}
case FILE_LINK_INFORMATION:
@@ -5983,7 +5985,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
return -EINVAL;
return smb2_create_link(work, work->tcon->share_conf,
- (struct smb2_file_link_info *)req->Buffer,
+ (struct smb2_file_link_info *)buffer,
buf_len, fp->filp,
work->conn->local_nls);
}
@@ -5993,7 +5995,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
return -EINVAL;
return set_file_disposition_info(fp,
- (struct smb2_file_disposition_info *)req->Buffer);
+ (struct smb2_file_disposition_info *)buffer);
}
case FILE_FULL_EA_INFORMATION:
{
@@ -6006,7 +6008,7 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
if (buf_len < sizeof(struct smb2_ea_info))
return -EINVAL;
- return smb2_set_ea((struct smb2_ea_info *)req->Buffer,
+ return smb2_set_ea((struct smb2_ea_info *)buffer,
buf_len, &fp->filp->f_path, true);
}
case FILE_POSITION_INFORMATION:
@@ -6014,14 +6016,14 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp,
if (buf_len < sizeof(struct smb2_file_pos_info))
return -EINVAL;
- return set_file_position_info(fp, (struct smb2_file_pos_info *)req->Buffer);
+ return set_file_position_info(fp, (struct smb2_file_pos_info *)buffer);
}
case FILE_MODE_INFORMATION:
{
if (buf_len < sizeof(struct smb2_file_mode_info))
return -EINVAL;
- return set_file_mode_info(fp, (struct smb2_file_mode_info *)req->Buffer);
+ return set_file_mode_info(fp, (struct smb2_file_mode_info *)buffer);
}
}
@@ -6102,7 +6104,7 @@ int smb2_set_info(struct ksmbd_work *work)
}
rc = smb2_set_info_sec(fp,
le32_to_cpu(req->AdditionalInformation),
- req->Buffer,
+ (char *)req + le16_to_cpu(req->BufferOffset),
le32_to_cpu(req->BufferLength));
ksmbd_revert_fsids(work);
break;
@@ -7548,7 +7550,7 @@ static int fsctl_pipe_transceive(struct ksmbd_work *work, u64 id,
struct smb2_ioctl_rsp *rsp)
{
struct ksmbd_rpc_command *rpc_resp;
- char *data_buf = (char *)&req->Buffer[0];
+ char *data_buf = (char *)req + le32_to_cpu(req->InputOffset);
int nbytes = 0;
rpc_resp = ksmbd_rpc_ioctl(work->sess, id, data_buf,
@@ -7661,6 +7663,7 @@ int smb2_ioctl(struct ksmbd_work *work)
u64 id = KSMBD_NO_FID;
struct ksmbd_conn *conn = work->conn;
int ret = 0;
+ char *buffer;
if (work->next_smb2_rcv_hdr_off) {
req = ksmbd_req_buf_next(work);
@@ -7683,6 +7686,8 @@ int smb2_ioctl(struct ksmbd_work *work)
goto out;
}
+ buffer = (char *)req + le32_to_cpu(req->InputOffset);
+
cnt_code = le32_to_cpu(req->CntCode);
ret = smb2_calc_max_out_buf_len(work, 48,
le32_to_cpu(req->MaxOutputResponse));
@@ -7740,7 +7745,7 @@ int smb2_ioctl(struct ksmbd_work *work)
}
ret = fsctl_validate_negotiate_info(conn,
- (struct validate_negotiate_info_req *)&req->Buffer[0],
+ (struct validate_negotiate_info_req *)buffer,
(struct validate_negotiate_info_rsp *)&rsp->Buffer[0],
in_buf_len);
if (ret < 0)
@@ -7793,7 +7798,7 @@ int smb2_ioctl(struct ksmbd_work *work)
rsp->VolatileFileId = req->VolatileFileId;
rsp->PersistentFileId = req->PersistentFileId;
fsctl_copychunk(work,
- (struct copychunk_ioctl_req *)&req->Buffer[0],
+ (struct copychunk_ioctl_req *)buffer,
le32_to_cpu(req->CntCode),
le32_to_cpu(req->InputCount),
req->VolatileFileId,
@@ -7806,8 +7811,7 @@ int smb2_ioctl(struct ksmbd_work *work)
goto out;
}
- ret = fsctl_set_sparse(work, id,
- (struct file_sparse *)&req->Buffer[0]);
+ ret = fsctl_set_sparse(work, id, (struct file_sparse *)buffer);
if (ret < 0)
goto out;
break;
@@ -7830,7 +7834,7 @@ int smb2_ioctl(struct ksmbd_work *work)
}
zero_data =
- (struct file_zero_data_information *)&req->Buffer[0];
+ (struct file_zero_data_information *)buffer;
off = le64_to_cpu(zero_data->FileOffset);
bfz = le64_to_cpu(zero_data->BeyondFinalZero);
@@ -7861,7 +7865,7 @@ int smb2_ioctl(struct ksmbd_work *work)
}
ret = fsctl_query_allocated_ranges(work, id,
- (struct file_allocated_range_buffer *)&req->Buffer[0],
+ (struct file_allocated_range_buffer *)buffer,
(struct file_allocated_range_buffer *)&rsp->Buffer[0],
out_buf_len /
sizeof(struct file_allocated_range_buffer), &nbytes);
@@ -7905,7 +7909,7 @@ int smb2_ioctl(struct ksmbd_work *work)
goto out;
}
- dup_ext = (struct duplicate_extents_to_file *)&req->Buffer[0];
+ dup_ext = (struct duplicate_extents_to_file *)buffer;
fp_in = ksmbd_lookup_fd_slow(work, dup_ext->VolatileFileHandle,
dup_ext->PersistentFileHandle);
--
2.34.1
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