diff options
| author | Ronnie Sahlberg <lsahlber@redhat.com> | 2019-07-09 18:41:11 +1000 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2019-07-10 16:15:45 -0500 |
| commit | df070afd9b8c952eacf49db54cae7138eb9deaeb (patch) | |
| tree | 537e6118629e984ee62764f450abe0bf66738f3b | |
| parent | f5f111c231f56e56e186c9a61a9d22fb8bf05faa (diff) | |
cifs: fix parsing of symbolic link error response
RHBZ: 1672539
In smb2_query_symlink(), if we are parsing the error buffer but it is not something
we recognize as a symlink we should return -EINVAL and not -ENOENT.
I.e. the entry does exist, it is just not something we recognize.
Additionally, add check to verify that that the errortag and the reparsetag all make sense.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
| -rw-r--r-- | fs/cifs/smb2ops.c | 14 | ||||
| -rw-r--r-- | fs/cifs/smb2pdu.h | 2 |
2 files changed, 12 insertions, 4 deletions
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 4b0b14946343..e704e04891fb 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -2605,26 +2605,32 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon, err_buf = err_iov.iov_base; if (le32_to_cpu(err_buf->ByteCount) < sizeof(struct smb2_symlink_err_rsp) || err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE) { - rc = -ENOENT; + rc = -EINVAL; + goto querty_exit; + } + + symlink = (struct smb2_symlink_err_rsp *)err_buf->ErrorData; + if (le32_to_cpu(symlink->SymLinkErrorTag) != SYMLINK_ERROR_TAG || + le32_to_cpu(symlink->ReparseTag) != IO_REPARSE_TAG_SYMLINK) { + rc = -EINVAL; goto querty_exit; } /* open must fail on symlink - reset rc */ rc = 0; - symlink = (struct smb2_symlink_err_rsp *)err_buf->ErrorData; sub_len = le16_to_cpu(symlink->SubstituteNameLength); sub_offset = le16_to_cpu(symlink->SubstituteNameOffset); print_len = le16_to_cpu(symlink->PrintNameLength); print_offset = le16_to_cpu(symlink->PrintNameOffset); if (err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE + sub_offset + sub_len) { - rc = -ENOENT; + rc = -EINVAL; goto querty_exit; } if (err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE + print_offset + print_len) { - rc = -ENOENT; + rc = -EINVAL; goto querty_exit; } diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 458bad01ca74..7e2e782f8edd 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -166,6 +166,8 @@ struct smb2_err_rsp { __u8 ErrorData[1]; /* variable length */ } __packed; +#define SYMLINK_ERROR_TAG 0x4c4d5953 + struct smb2_symlink_err_rsp { __le32 SymLinkLength; __le32 SymLinkErrorTag; |