cifs: return correct error in ->calc_signature()

If an error happens while getting the key or session in the
->calc_signature implementations, 0 (success) is returned. Fix it by
returning a proper error code.

Since it seems to be highly unlikely to happen wrap the rc check in
unlikely() too.

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Fixes: 32811d242ff6 ("cifs: Start using per session key for smb2/3 for signature generation")
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index 1a5fc3314dbf5790dcf14de8e8039a9d95f92fcd..4640fc4a8b133d5b0f7a74a9c59a7520d87d8932 100644 (file)
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -225,9 +225,9 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
        struct smb_rqst drqst;
 
        ses = smb2_find_smb_ses(server, le64_to_cpu(shdr->SessionId));
-       if (!ses) {
+       if (unlikely(!ses)) {
                cifs_server_dbg(VFS, "%s: Could not find session\n", __func__);
-               return 0;
+               return -ENOENT;
        }
 
        memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
@@ -557,8 +557,10 @@ smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
        u8 key[SMB3_SIGN_KEY_SIZE];
 
        rc = smb2_get_sign_key(le64_to_cpu(shdr->SessionId), server, key);
-       if (rc)
-               return 0;
+       if (unlikely(rc)) {
+               cifs_server_dbg(VFS, "%s: Could not get signing key\n", __func__);
+               return rc;
+       }
 
        if (allocate_crypto) {
                rc = cifs_alloc_hash("cmac(aes)", &hash, &sdesc);